While seasonality of birth outcomes has been documented in a variety of settings, data from rural South Asia are lacking. We report a descriptive study of the seasonality of prematurity, low birth weight, small for gestational age, neonatal deaths, and stillbirths in the plains of Nepal.Using data collected prospectively during a randomized controlled trial of neonatal skin and umbilical cord cleansing with chlorhexidine, we analyzed a cohort of 23,662 babies born between September 2002 and January 2006. Project workers collected data on birth outcomes at the infant’s household. Supplemental data from other studies conducted at the same field site are presented to provide context. 95% confidence intervals were constructed around monthly estimates to examine statistical significance of findings.Month of birth was associated with higher risk for adverse outcomes , even when controlling for maternal characteristics. Infants had 87% (95% CI: 27 – 176%) increased risk of neonatal mortality when born in August, the high point, versus March, the low point.Seasonality of neonatal deaths, stillbirths, birth weight, gestational age, and small for gestational age were found in Nepal. Maternal factors, meteorological conditions, infectious diseases, and nutritional status may be associated with these adverse birth outcomes. Further research is needed to understand the causal mechanisms that explain the seasonality of adverse birth outcomes.The online version of this article (doi:10.1186/1471-2393-14-310) contains supplementary material, which is available to authorized users. There is a well-documented relationship between seasonality and poor birth outcomes, which varies across populations and geographic regions–3. VarioThe majority of these studies have been conducted in high-income countries with relatively few from low- and middle-income countries where the effects of these factors may be greater, 7–10. IThis study aims to provide a descriptive analysis of seasonality of birth outcomes over an approximately three-year period in the rural plains of Nepal. In spite of progress made by Nepal in meeting its Millennium Development Goal 4 for child mortality, adverse pregnancy outcomes and early child mortality are still high. ExaminaThe Nepal Nutrition Intervention Project study area is based in Sarlahi district, a rural community in the low-lying plains of Nepal. The data were collected as part of a previously published community-based, cluster-randomized, placebo-controlled trial of chlorhexidine skin and umbilical cord cleaning on neonatal morbidity and mortality conducted from September 2002 to January 2006, 13. BriData were prospectively collected on neonatal mortality, stillbirths, birth weight, and gestational age. Local female health care workers visited all households in the study area monthly in order to identify, consent and enroll incident pregnancies (at approximately ~6 months gestation). All enrolled women received 90 days of iron-folic acid supplements, weekly vitamin A supplementation, deworming, and a clean delivery kit, and women for whom tetanus vaccination was indicated were offered the vaccine. Project workers visited the households (~92% were home births) as soon as possible after delivery for a maternal and newborn health assessment. Project workers visited households a total of ≤11 times  to assess infant morbidity and mortality. Infants were weighed as soon as possible after birth using a digital scale  that measured weight to within 2 grams. Women were asked to report the month of pregnancy at the time of enrollment; soon after delivery they were asked again to estimate the length of the pregnancy in months. These two separate reports both yielded estimates of gestational age at delivery, which were then averaged to estimate the final gestational age for analysis.We obtained daily maximum and minimum temperature recordings (in Celsius) from Simra  and Janakpur  airports, which are approximately 52 km east and 60 km west, respectively, of the geographical center of the study area . Data onWe present descriptive analyses of birth outcomes by month. Neonatal and perinatal mortality was anchored on month of birth . Births were considered stillbirths if the mother reported that her infant neither cried, moved, nor breathed following delivery, and gestational age was 28 weeks or greater. The stillbirth rate was calculated as the number of stillbirths over the total number of live births plus stillbirths (multiplied by 1000). Infants were categorized into term (≥37 weeks), preterm (<37 weeks), and very preterm (<34 weeks) gestational age categories based on completed weeks of gestation. Birth weights were included only if collected within 72 hours of birth. Infants were categorized into three birth weight categories: (1) normal weight ≥2500 grams (g), (2) low birth weight <2500 g, and (3) very low birth weight <2000 g. Two sex-specific analytic methods were used to identify infants who were SGA: the 10th percentile cut-off described by Alexander and the 23,662 infants were enrolled from September 2002-January 2006  with a substantial monthly variation [range: 21.6 – 40.4] . The prevalence of low birth weight (<2500 g) and very low birth weight (<2000 g) was 30.5% (95% CI: 29.9 – 31.1) and 5.1% (95% CI: 4.8 – 5.4), respectively  of births were preterm (<37 weeks)  and 29.9% (95% CI: 29.2 – 30.5) using the <10% and <3% criteria, respectively  and 1.4% (95% CI: 1.3 – 1.6) using the <10% and <3% criteria, respectively. The percent SGA (<10%) and preterm ranged from a low of 3.2% (95% CI: 2.3- 4.3) in May to 6.0% (95% CI: 5.0 – 7.1) in October. Infants had the highest risk of being preterm and SGA (<10%) in September and October  while neonatal mortality was increased from the hot and dry season through to post-monsoon season (April – October). Low birthweight and SGA had a similar pattern with increased prevalence from monsoon to post-monsoon (August – November), while high preterm prevalence was primarily during post-monsoon (September to November).Pahadi (hills) and the Madeshi (plains)[Pahadi are in general better off economically and have better health and nutritional status than the Madeshi. The Madeshi are more likely to give birth in April to May and August to November (data not shown) than the Pahadi. Literacy has a similar pattern with illiterate women more likely to give birth in March to May and September-December. Women from the lowest socioeconomic quartile are also most likely to give birth in April and September to December. These categories overlap with each other and also correspond with the pattern of higher prevalence of preterm birth and low birth weights in April and August to November. Despite these differences in birth timing by maternal characteristics, our model shows that controlling for these factors does not statistically significantly change the monthly patterns observed in birth outcomes.One theory postulated for seasonality of birth outcomes is that mothers with different socioeconomic and other characteristics preferentially marry and give birth at different times of the year, 18–21. (plains). The PahFood insecurity has also been shown to be associated with poor birth outcomes. A studyFactors related to the environment including temperature, humidity, and sunlight have been associated with birth outcomes, 25–35. Other investigators have found a risk for preterm births when mothers were exposed to high ambient temperature or high heat-humidity index near the time of delivery, 31, 32.The literature regarding temperature and low birth weight is less consistent. Etler and Murray found low temperatures in the 2nd trimester were associated with low birth weight, 29. A sTustin found that exposure to high levels of sunshine during the 1st trimester was associated with increased birth weight, postulating that light exposure increases levels of insulin-like growth factor, important for fetal growth. Torche One recent US study used a within-mother analysis to control for maternal factors and found a persistent seasonal pattern of birth outcomes with the highest risk for preterm birth in January and February. The autPlasmodium vivax only) with no clinical malaria so this is unlikely to play an important role in adverse birth outcomes as it might in Sub-Saharan Africa[Neisseria gonorrhoeae (1.0%) and Chlamydia trachomatis (2.3%)[One study from the Gambia suggests that a peak in preterm births in October is associated with peak time for malaria infections although the evidence is not conclusive. A previn Africa. Anothern Africa, which mn Africa. Maternan Africa. Data frs (2.3%). The impAs with all ecological associations, this study cannot identify a causal link between season of birth and poor birth outcomes. While we used regression to model seasonality of outcomes, controlling for maternal characteristics, this was not an exhaustive model and was missing potential factors, which were unmeasured in our study such as maternal infections and nutritional deficiencies. A second limitation is that we cannot isolate the true period or periods of exposure that are causally linked to various adverse birth outcomes. For example, the relative importance of exposure(s) immediately preceding the birth or accumulated exposure over different gestational periods is unknown. AnotherOur ascertainment of gestational age is based on women’s recall of last menstrual period, which may lead to misclassification of preterm. Our population estimates of preterm and SGA, however, are similar to those found in a previous study at our field site that used more sensitive gestational age measures. We expeAs our study was nested within a randomized controlled trial, there was some impact on neonatal outcomes from iron supplementation . Given the reverse J-shape of the mortality curve, these infants who died soon after birth would likely be lower birthweight (if preterm) or higher birthweight (thus at increased risk for birth asphyxia due to obstructed labor) compared to infants who did not die soon after birth. In our  results. The preterai region, where the majority of the Nepalese population lives and is comparable to infant health outcomes in Nepal as a whole. For example, the neonatal mortality rate is our study (32 deaths per 1000 live births) was quite similar to the neonatal mortality for Nepal as a whole during a similar period (33 deaths per 1000 live births)[Strengths of this work are that it is a large, prospective, population-based study that is representative of South Asian populations for which we have birth weight, gestational age and survival outcomes. With a refusal rate of less than 1% and the sampling of all pregnant women in the study area the data are highly representative of Sarlahi District. Sarlahi District, is located in the  births). The liv births).Ecological association studies such as this provide a guide to more definitive studies in the search for causal factors in adverse birth outcomes. One way to evaluate these potential seasonal risk factors in Nepal would be to intervene and to assess whether a specific intervention reduces the seasonality of the adverse birth outcomes. For example, the government of Nepal is now encouraging antenatal visits and facility deliveries with a conditional cash transfer program. The expSTROBE Statement checklist.(DOC 85 KB)Additional file 1:Additional file 2: Table S1: Stillbirths, Early Neonatal, Perinatal, and Neonatal Mortality Rates and Numbers by Month. (DOCX 304 KB)Additional file 3: Table S2: Low Birth weight Category by Month. (DOCX 95 KB)Additional file 4: Figure S1: Mean Birthweight by Sex and Month. (DOCX 53 KB)Additional file 5: Table S3: Preterm Category by Month. (DOCX 90 KB)Additional file 6: Figure S2: Average Gestational Age by Month. (DOCX 50 KB)Additional file 7: Table S4: Small for Gestational Age by Month. (DOCX 93 KB)Additional file 8: Table S5: Small for Gestational Age & Preterm by Month. (DOCX 89 KB)Additional file 9: Figure S3: Percent Small for Gestational Age and Preterm by Month. (DOCX 61 KB)Additional file 10: Figure S4: Food Insecurity by Month (From NNIPS cohort September 2006 – March 2008). (DOCX 49 KB)Additional file 11: Figure S5: Average Max and Min Temperatures. (DOCX 54 KB)Additional file 12: Table S6: Summary of Monthly Prevalence of Neonatal Outcomes Peaks and Troughs and Risk Factor Peaks. (DOCX 185 KB)Additional file 13: Table S7: Logistic Regression for Main Outcomes. (DOCX 467 KB)Additional file 14: Table S8: Comparison of Characteristics between those with birthweights and those with birthweights missing/collected >72 hours. (DOCX 62 KB)


Objective: The association of low birth weight (LBW) with adult onset diseases like hypertension is suggested to be partially mediated by a low number of nephrons at birth. Studies have established a relation between LBW and renal volume as the latter is a surrogate marker of total nephron number. Most such studies have considered birth weight or gestational age as separate independent predictors, without taking into consideration the baby’s weight with respect to its gestational age. This study aims to investigate the influence of weight for gestational age on kidney volume in newborns.Methods: Consecutive newborns delivered in the department of neonatology in a tertiary care medical college and hospital, were included in a cross-sectional study. The subjects were classified as appropriate for gestational age (AGA) and small for gestational age (SGA) as per Lubchenco’s charts of weight for gestational age (WGA). Bilateral kidney dimensions were measured by a single observer and combined kidney volumes were calculated and compared between the groups.Findings: Four hundred and seventeen newborns  were included. The mean combined kidney volume (CKV) was significantly lower among SGA newborns (13.85±4.02 cm3) compared to that of AGA (16.88±4.53 cm3) (P<.001). Univariable and multivariable analyses were done for assessing the effect of demographic, anthropometric and maternal parameters on CKV. WGA, crown heel length, gestational age and postnatal age (hours of life) were independent predictors of mean CKV. An SGA newborn was expected to have a mean CKV 1.57 cm less (95% CI -2.49 cm to -0.65 cm) than that of its AGA counterpart.Conclusion: Considering the future implications of being SGA and having low kidney volumes at birth, it is essential to have an objective depiction of the relationship between these two vital parameters. This study from the Indian subcontinent brings forth such an association. Several animal models, epidemiological and retrospective human studies have demonstrated that the association of LBW with subsequent hypertension is mediated, at least in part, by a congenital deficit in nephron number[5-9]. The number of glomeruli correlates with renal mass, but both these parameters cannot be measured in vivo. So, renal volume, which is proportional to renal mass, has been used as a surrogate marker of low nephron number .Low birth weight (LBW) has been identified as a risk factor for development of adult-onset diseases, including hypertension, type 2 diabetes and poor renal course. Barker et al and Brenner et al hypothesized a deficit in nephron number to be the explanation for this fetal programming of adult disease. Antenatal ultrasonography of human fetuses have shown that intrauterine growth retardation is associated with reduced kidney volume[13-15]. However, most such studies assessing renal volume have considered birth weight or gestational age as separate independent predictors, without taking into consideration the baby’s weight with respect to its gestational age. This study aims to investigate the influence of weight for gestational age on kidney volume in newborns. It has been seen in studies that renal volume is lower in children and adults who had low birth weight compared to those who had normal birth weightA cross-sectional study was conducted in the department of neonatology in a tertiary care medical college and hospital. Ethical approval was obtained from the institutional ethical committee. After taking informed consent, consecutive newborns delivered in the same hospital were screened for inclusion into the study. The exclusion criteria were major congenital anomalies, severe birth asphyxia (defined as Apgar score at 5 minutes ≤3 and/or cord pH ≤7.0), any major illness with hemodynamic instability, known acute kidney injury (defined as an abrupt (<48 hrs) reduction of kidney function manifesting as urine output <0.5ml/kg/hr for >6 hours and/or increase in serum creatinine of ≥0.3mg/dl or ≥50%), use of nephrotoxic drugs in the immediate postnatal period and refusal of consent.[16] The subjects were then classified as appropriate for gestational age (AGA), small for gestational age (SGA) or large for gestational age (LGA) based on Lubchenco’s reference charts for assessment of weight for gestational age[17]. SGA was defined as weight below the 10th percentile for gestational age, AGA as weight between10th and 90th percentile and LGA as weight above the 90th percentile for gestational age as per Lubchenco’s reference charts[18]. Ponderal index (PI) defined as weight in grams/length[3] was calculated for those infants identified as SGA[19]. The SGA infants were then further classified into two groups: low PI  and appropriate PI (PI between 10th and 90th percentile) as per Lubchenco’s Ponderal index-gestational age distribution[20]. Some maternal parameters like parity, antenatal hemoglobin, and known medical or surgical illness were also obtained from maternal records. The details of the included subjects like gestational age, birth weight, gender, hours of postnatal life, Apgar score, head circumference, crown-heel length and crown-rump length were recorded. Birth weight, obtained from birth records, was taken by a digital weighing scale to the nearest 0.005 kg. Body length was measured supine with an infantometer to the nearest 0.1 cm. The gestational age was determined by the date of last menstrual period, antenatal ultrasound and confirmed by Modified Ballard’s scoring system[21].  All the included subjects underwent ultrasonological evaluation for kidney size. Ultrasound was done by a single observer who was blinded to the anthropometric parameters of the subject. Kidney size was determined by USG using 3.5- 5 MHZ sector probe. For examination of right kidney child was placed in left lateral position and vice versa for left kidney. The kidney was identified in the sagittal plane along its longitudinal axis. In this position, longitudinal measurements of the largest length were performed. The probe was then rotated 90 degrees and cross-sectional anteroposterior measurements of the width and depth at the hilar level were performed. All dimensions were measured to the nearest 0.1 cm in both kidneys. Kidney volume was then calculated in cubic centimeters using the equation of an ellipsoid: volume = mean length ×mean width × mean depth × 0.523 Descriptive statistics like mean and standard deviations for continuous variables and frequencies for categorical variables were calculated. The mean combined (right and left) kidney volume (CKV) was compared among AGA, SGA and LGA groups of infants by ANOVA test of significance with post-hoc Tukey test for individual comparisons. 2. The correlation between mean combined kidney volume and significant continuous variables was also determined. Significance was taken at a P value of 0.05. All statistical analysss was done by SPSS version 16.Univariable and multivariable linear regression analyses were done to assess the effect of confounders. The multivariable linear regression model was made taking those parameters which were found to be significant in univariable analysis, excluding the ones showing co linearity. Model performance was judged by adjusted R3) compared to that of AGA (16.88±4.53 cm3) and LGA (20.99±5.87 cm3) subjects (P<.001). Further comparison of CKV between the subgroups of SGA (low versus appropriate PI) failed to show any significant difference. As the number of LGA infants was minimal (19), further analyses were done taking LGA and AGA together as one composite group and named AGA for convenience. Some demographic, anthropometric and maternal parameters were assessed by univariable analysis for their effect on the mean CKV . . Researchers have recognized low birth weight, kidney size, prematurity and short stature as some of the clinical surrogates of nephron number.  As evidence is increasing regarding the role of the kidney and the number of nephrons at birth in determining diseases in later life, it is imperative to identify markers of nephron number for risk stratification and monitoring. Spencer et al estimated an increase in kidney volume of about 15 ml/1.73 m2 for every kilogram increase in birth weight. Their study had adjusted for the effect of age and gender, but not for gestational age10. Similarly, birth weight was found to be an independent predictor of the glomerular number, in an autopsy study of kidneys[27]. However, the kidneys of older children or adults were measured and compared between those who had low birth weight and those who had normal birth weight. The size of the kidneys in older ages may be influenced by environmental and extraneous factors and may not reflect solely the impact of birth weight[30]. Also, the size of the kidney in later ages may in no way be related to the number of nephrons at birth, as glomerulii may undergo adaptive changes like hypertrophy. The effect of intrauterine growth on the kidneys is best manifested at birth. Moreover, in the studies mentioned above, the gestational ages at birth were not available, so the contribution of prematurity on kidney size could not be ascertained in such studies.  Many studies in literature have shown that low birth weight is associated with reduced kidney size. Some authors have investigated the kidney size by antenatal ultrasound taking into account the weight for gestational age[13-15]. It was observed that renal volume in the intrauterine growth-restricted fetuses was less than that in the group of fetuses that were not intrauterine growth restricted after adjusting for gestational age[13]. Though WGA has been considered here, the fetal weight taken in these studies is either an estimated one, or, the classification into SGA and AGA has been done after birth.  Various observations have established a relation between kidney volume and gestational age, working out mathematical models to calculate the association. Such an association was also evident from our study, with an expected increase of 0.23 cm in CKV for every week increase in gestational age. Many of the studies showing this relationship have been done by antenatal ultrasonography of fetal kidneys, without considering the secondary effect of other factors like fetal weight, IUGR. Our study established an independent association between crown-heel length of the newborn and renal size. The length/height of a child is another parameter which has been found to be a surrogate marker of renal size, though, this has mostly been studied in older children and hence the effect of IUGR or SGA could not be assessed[25]. This has also been observed as a rapid catch-up growth in SGA newborns up to 3 months of age, by Giapros et al[35]. It has been shown in our study, that irrespective of the influence of other variables, the kidney volume increases by 0.05 cm for every increasing hour of postnatal life.  It has been shown that the renal size increases with increasing postnatal age[35]. However, this study dealt with only one aspect of renal size , without taking the entire kidney volume into consideration. It was demonstrated in a study by Schmidt et al, that WGA had a stronger influence than crude birth weight or gestational age on CKV at birth[25]. They suggested that analyses of the impact of intrauterine growth retardation on kidney size or function should take into account WGA, instead of birth weight alone. Our study brings forth such an association. It shows that after adjusting for secondary effect of other variables  an SGA newborn was expected to have a mean CKV 1.57 cm less (95% CI -2.49 cm to -0.65 cm) than that of its AGA counterpart. It is essential to establish a quantitative relationship between neonatal renal volume and birth weight of the newborn with respect to his gestational age or, in other words, weight for gestational age. Such a difference in kidney size between SGA and AGA newborns has hardly been studied. Giapros et al were one of the few research groups who identified smaller kidneys in SGA infants compared with the AGA infants[35-39]. Our study has dealt with the composite combined (left and right) kidney volume, which should be a better indicator of renal mass or total nephron number, rather than any single dimension. Keeping in mind the future risk implication of total nephron number at birth, determinants of kidney volume would be more practically useful. Studies assessing newborn kidney size and its determinants have deduced correlations between somatic parameters and different dimensions of the kidney size like length, depth or width. Many researchers have shown interest particularly in kidney length In the present study there was no significant difference in kidney volumes between those with low PI or asymmetrical IUGR versus those with appropriate PI or symmetrical IUGR, indicating that all SGA newborns have low kidney volumes, irrespective of the time of intrauterine insult. . India is a country with one of the highest number of low birth weight deliveries in the world[42]. Also, the country is witnessing increasing incidence of hypertension, diabetes over the last decade[43]. Therefore, it is logical to study renal volumes of newborns in such a country. Though sonographic studies for renal dimensions have been carried out in India, most of them are in children of different ages and the focus was not on kidney growth in SGA infants[44-46]. Though the study by Gupta et al. assessing renal dimensions in neonates, is informative, it included only AGA newborns[47].  Since the proposal of the fact that intrauterine kidney growth is strongly associated with morbidity in later life, a lot of interest has been shown by researchers in investigating these parameters in communities where low birth weight is common The limitation of our study is that some of the other confounding factors like maternal age, pre-conceptional weight and nutritional status could not be adjusted for, in the multivariable model, as these parameters were not available.This study brings forth the difference in kidney volumes between AGA and SGA newborns. Considering the future implications of being SGA and having low kidney volumes at birth, it is essential to have objective depiction of the relationship between these two vital parameters. Such a study of SGA newborns from the Indian subcontinent is expected to contribute substantially to the entire gamut of medical research concerning the role of intrauterine kidney growth in programming adult diseases.


Low birth weight and unhealthy lifestyles in adulthood have been independently associated with an elevated risk of hypertension. However, no study has examined the joint effects of these factors on incidence of hypertension.We followed 52,114 women from the Nurses’ Health Study II without hypercholesterolemia, diabetes, cardiovascular disease, cancer, prehypertension, and hypertension at baseline (1991–2011). Women born preterm, of a multiple pregnancy, or who were missing birth weight data were excluded. Unhealthy adulthood lifestyle was defined by compiling status scores of body mass index, physical activity, alcohol consumption, the Dietary Approaches to Stop Hypertension diet, and the use of non-narcotic analgesics.Pinteraction <0.001). The proportions of the association attributable to lower term birth weight alone, unhealthy lifestyle alone, and their joint effect were 23.9 % , 63.7 % , and 12.5 % , respectively. The population-attributable-risk for the combined adulthood unhealthy lifestyle and low birth weight at term was 66.3 % .We documented 12,588 incident cases of hypertension during 20 years of follow-up. The risk of hypertension associated with a combination of low birth weight at term and unhealthy lifestyle factors  was more than the addition of the risk associated with each individual factor, indicating a significant interaction on an additive scale (The majority of cases of hypertension could be prevented by the adoption of a healthier lifestyle, though some cases may depend on simultaneous improvement of both prenatal and postnatal factors. Hypertension affects one third of American adults  and is tHowever, no previous study has examined the joint associations of birth weight and adulthood lifestyle with hypertension risk, or evaluated their potential interactions. In this study, we prospectively assessed the joint association of birth weight at term – a marker of fetal growth restriction – and established lifestyle risk factors in adulthood with incident hypertension in the Nurses’ Health Study (NHS) II .In 1989, 116,430 female registered nurses aged 25 to 42 years enrolled in NHS II by completing and returning an initial questionnaire that provided detailed information on medical history, lifestyle, and medications. The dietary survey was initiated using a food frequency questionnaire (FFQ) in 1991, which served as the baseline of the present analysis. Detailed information on lifestyle habits and medical history was updated biennially; FFQ was updated every 4 years. The follow-up for the cohort exceeded 90 % of eligible person-time.2) as those with relative information.In 1991, 100,090 participants returned the questionnaire including a FFQ. For the current analysis, we excluded participants (1) who reported diagnosis of hypertension, ever use of antihypertensive medication, or who reported median systolic blood pressure in the prehypertensive range, greater than 120 mmHg or diastolic blood pressure greater than 80 mm Hg, at or before baseline of the current analysis ; (2) who reported physician diagnosis of other chronic conditions, including hypercholesterolemia, diabetes, cardiovascular disease, and cancer at baseline ; (3) who had missing data on dietary, physical activity, alcohol consumption, use of non-narcotic analgesics, or body weight at baseline ; and (4) who were born preterm , did not provide birth weight data , or who were born of a multiple pregnancy (n = 687). After these exclusions, 52,114 women were included in the analysis. Participants who did not report birth weight or missed lifestyle factors had similar age (mean 36.3 ± 4.7 vs 36.0 ± 4.7 years) and body mass index  , unhealthy lifestyle alone as [(RRg0e1 – 1)/ (RRg1e1 – 1)], and to their interaction using the equations as [RERI/(RRg1e1 – 1)], the detail information on the equation has been previously published [We further proceeded with the decomposition of the joint effect, e.g. the proportions attributable to a lower term birth weight alone as [ using the standard equation  as,\docuThe estimated PAR% was the percentage of incident hypertension in the study population that theoretically would not have occurred if all people had been in the low-risk group, combining a healthy birth weight at term and a healthy lifestyle, assuming a causal relation between the risk factors and hypertension.P <0.05.Data were analyzed using a commercially available software program , and statistical significance was set at a two-tailed Table We documented 12,588 new cases of hypertension during the 20 years of follow-up. We observed a consistent, graded inverse association between birth weight at term and risk of hypertension . The graded decreasing risk of hypertension with increasing of birth weight at term appeared consistent across all levels of unhealthy lifestyle factors  per 1-kg lower birth weight at term and 1.61  per 1-point higher unhealthy lifestyle score. In addition, we observed that the risk of hypertension associated with a combination of low birth weight at term and unhealthy lifestyle factors  was more than addition of the risk associated with each individual factor, indicating a significant interaction on an additive scale  for risk of hypertension. The PAR% for not being in this group was 66.3 %, indicating 66 % of the new cases of hypertension in our cohort could have potentially been prevented if they had all five healthy lifestyle factors combined with a birth weight at term 2.5–4.49 kg (Table P for additive interaction <0.0001). When we applied the expanded low-risk lifestyle score, the RRs of hypertension were 1.28  per 1-kg lower birth weight at term, 1.46  per 1-point higher unhealthy lifestyle score (5- expanded low-risk lifestyle score), and 1.84  for their joint effect, with a RERI of 0.10 . We also performed analysis of the main research question based on the cross-sectional data at baseline including all participants without missing data of birth weight and lifestyle factors. The odds ratios of hypertension were 1.09  per 1-kg lower birth weight at term, 1.62  per 1-point higher unhealthy lifestyle score, and 1.78  for their joint effect, with a RERI of 0.07 .We performed several sensitivity analyses. In order to examine potential confounding of socioeconomic status (SES), we added self-ranking of their standing in US society, including their money, education, and jobs, as a surrogate of the SES to the multivariable-adjusted model. The SES adjusted RRs of hypertension were 1.22  per 1-kg lower birth weight at term, 1.59  per 1-point higher unhealthy lifestyle score, and 1.93  for their joint effect, with a RERI of 0.12 (95 % CI, 0.09–0.14; After 20 years of follow-up of a large population of initially hypertension-free young women, we observed that the risk of hypertension associated with a combination of low birth weight at term and unhealthy lifestyle factors was more than the addition of the risk associated with each of these factors, indicating a significant interaction on an additive scale. Our data indicate that combination of a healthy birth weight and a healthy adulthood lifestyle could prevent 66 % of the cases of hypertension in this population.It is hypothesized that restricted fetal growth reflects maternal vascular stress inherited by her children, and which may also interact with adulthood lifestyle , 29. EveIt is widely accepted that hypertension can be prevented by lifestyle modifications. The National High Blood Pressure Education Program Coordinating Committee published its first statement on the primary prevention of hypertension in 1993  and updaOur study also indicates that 12 % of hypertension cases may only occur if both unhealthy birth weight and unhealthy lifestyle were present, not if only one or the other is present . This fiA major strength of the present study is decomposition of the joint effect of birth weight and adulthood lifestyle factors. Our study, for the first time, quantitatively estimated the joint effects of prenatal and adulthood risk factors on risk of hypertension. Other strengths of the present study include the large number of incident hypertension cases, long-term follow-up, and repeated measurement of lifestyle factors during the 20 years of follow-up.Our study has several limitations. First, our cohorts included mostly Caucasian women and the PAR was population-specific, which limited the generalizability to men or other ethnic groups of women. However, the relative homogeneity of the study populations in educational attainment and SES enhances the internal validity. The prevalence of low-risk factors in the NHS II women is much higher than that among Black and Hispanic women , while tIn conclusion, our findings suggest that the effects of fetal growth restriction and unhealthy lifestyle on the risk of hypertension are greater than additive. Though some cases of hypertension may only be prevented by simultaneous improvement of both prenatal and postnatal factors, the majority of cases of hypertension could be prevented by the adoption of a healthier lifestyle.


It is well known that hepatic hemodynamics is an important physiologic mechanism in the regulation of cardiac output (CO). It has been reported that maternal cardiac output relates to neonatal weight at birth.In this study, we assessed the correlation between maternal hepatic vein Doppler flow parameters, cardiac output and neonatal birth weight.2 goodness of fit in SPSS 22.0.Healthy women with uncomplicated second or third trimester pregnancy attending the outpatient antenatal clinic of Ziekenhuis Oost-Limburg in Genk (Belgium), had a standardized combined electrocardiogram-Doppler ultrasound with Impedance Cardiography, for measurement of Hepatic Vein Impedance Index (HVI  =  [maximum velocity – minimum velocity]/maximum velocity), venous pulse transit time  and cardiac output (heart rate x stroke volume). After delivery, a population-specific birth weight chart, established from a cohort of 27000 neonates born in the index hospital, was used to define customized birth weight percentiles (BW%). Correlations between HVI, VPTT, CO and BW% were calculated using Spearman's ρ, linear regression analysis and RA total of 73 women were included. There was a negative correlation between HVI and VPTT . Both HVI and VPTT correlated with CO  and with BW% Our data illustrate that the known contribution of hepatic hemodynamics in the regulation of cardiac output is also true for women with uncomplicated pregnancies. Our study is the first to illustrate a potential link between maternal hepatic hemodynamics and neonatal birth weight. Whether this link is purely associative or whether hepatic vascular physiology has a direct impact on fetal growth is to be evaluated in more extensive clinical and experimental research. One of the main functions of the venous system is the regulation of cardiac output. The cardiovascular circuit is a closed circulatory loop, implicating that in steady state conditions the venous flow back to the heart (i.e. preload) is equal to the arterial flow towards the organs (i.e. cardiac output). Due to the Frank-Starling mechanism, an increase in venous return will automatically lead to an increase in cardiac output and vice versa. Next to this, the venous compartment is also a capacitance reservoir: storage of non-circulating reserve blood occurs in the splanchnic bed and liver, from where this can be mobilised into the circulation whenever necessary. This mobilization occurs via the portal vein and the liver. As such, the hepatic circulation is actively involved in the regulation of cardiac output, both in a direct and indirect way Changes of maternal cardiac output start already in early gestation An integrated assessment of the cardiovascular loop can be done non-invasively by the use of impedance cardiography (ICG) and combined electrocardiogram – Doppler (ECG-D) sonography The aim of the study was to investigate whether a relation exists between maternal ICG and/or ECG-D parameters and neonatal birth weight percentiles. As hepatic hemodynamics has a physiological role in the regulation of CO and CO is known to correlate with BW%, we hypothesize that HVI correlates with BW%.The study protocol was approved by the local Ethics Committee of Hasselt University and Hospital Oost-Limburg (CME ZOL reference 08/049 and 09/050). Written informed consent was obtained.Pregnant women in their second or third pregnancy trimester with or without gestational complications, attending the outpatient antenatal clinic, were invited to participate in this observational study. After written informed consent, a non-invasive cardiovascular assessment was performed according to a standardised protocol as reported elsewhere Customized birth weight charts were established from a cohort of 27000 neonates, born as singletons without congenital anomalies in Ziekenhuis Oost-Limburg between 2001 and 2013. Charts were categorized into 4 groups: primiparous & baby girl, primiparous & baby boy, multiparous & baby girl, multiparous & baby boy. Birth weights were classified per week of gestation, and birth weight percentiles (BW%) were calculated with an interval of 2.5% between P2.5 and P97.5. According to these population-specific data, the weight at birth of each neonate in the study was expressed as a customized birth weight percentile.ICG examinations were performed in standing position using the Non-Invasive Continuous Cardiac Output Monitor , according to a standard protocol as described max, Vmin) were measured, and a hepatic venous impedance index (HVI) was calculated as [Vmax-Vmin/Vmax]. Venous pulse transit times (VPTT) were measured as the time interval between the P-wave of the ECG and the corresponding A-wave of the venous Doppler wave, corrected for heart rate [PA/RR] The ECG-Doppler assessment was performed by four ultra-sonographers  with known intra- and interobserver correlation 2 goodness of fit and p-value, which was considered significant at nominal level α <0.05.Statistical analyses were done using SPSS 22.0. Shapiro Wilk was performed to assess normal distribution of VI, VPTT, CO and BW%. Data were recorded as median + interquartile range. Rank-based Spearman's ρ correlation coefficient was calculated to assess the relation between HVI, CO, VPTT and BW%. For each relation, linear regression analysis was performed with calculation of RFrom a total of 309 women, 236 pregnant women were excluded due to maternal, gestational or fetal problems 2 and p values are presented in Correlations between HVI, VPTT, CO and BW% are shown in This study aimed to investigate the relation between maternal cardiac output, maternal hepatic venous function and birth weight percentiles during healthy pregnancy. We observed that HVI and VPTT (hepatic venous parameters), both measured by ECG-Doppler, correlate with maternal CO as measured by ICG, which in turn correlates with birth weight percentiles. Moreover, the hepatic venous parameters also show a significant correlation with the birth weight percentiles.This study's strengths are the use of rigid protocols for ICG and ECG-D assessment with reliable measurements and known inter- and intra-observer correlations, as well as customized population-specific birth weight charts. As all included women had antenatal care and delivery in the same hospital, all data on gestational, maternal and neonatal outcome are complete and directly available from the hospital records. The use of ICG for measuring maternal cardiac output during pregnancy may be subject of criticism An influence of the maternal CO on birth weight is already observed in other studies, supporting a physiological role of maternal cardiac output on fetal growth The venous compartment cooperates with the heart as one functional unit to regulate venous return and cardiac output A new and interesting observation from our study is the correlation between hepatic venous Doppler indices and neonatal birth weight percentile . From thFrom the data presented in this paper, we conclude that in healthy women with uncomplicated pregnancies a correlation exists between hepatic vein Doppler parameters, maternal cardiac output and fetal birth weight percentiles. The role of hepatic hemodynamics in the regulation of cardiac output of non-pregnant individuals, and the relevance of maternal cardiac output towards fetal growth are well known. However our data show for the first time a potential link between maternal hepatic hemodynamics and neonatal weight at birth. Whether this link is purely associative or whether hepatic vascular physiology has a direct impact on fetal growth is to be evaluated in more extensive clinical and experimental research.


Rannasangpei (RSNP) is used as a therapeutic agent in the treatment of cardiovascular diseases, neurological disorders, and neurodegeneration in China; however, its potential use in the treatment of vascular dementia (VD) was unclear. In this study, our aim was to examine the neuroprotective effect of RSNP in a VD rat model, which was induced by permanent bilateral common carotid artery occlusion (2VO). Four-week administration with two doses of RSNP was investigated in our study. Severe cognitive deficit in the VD model, which was confirmed in Morris water maze (MWM) test, was significantly restored by the administration of RSNP. ELISA revealed that the treatments with both doses of RSNP could reinstate the cholinergic activity in the VD animals by elevating the production of choline acetyltransferase (ChAT) and reducing the acetylcholinesterase (AChE); the treatment of RSNP could also reboot the level of superoxide dismutase (SOD) and decrease malondialdehyde (MDA). Moreover, Western blot and quantitative PCR (Q-PCR) results indicated that the RSNP could suppress the apoptosis in the hippocampus of the VD animals by increasing the expression ratio of B-cell lymphoma-2 (Bcl-2) to Bcl-2-associated X protein (Bax). These results suggested that RSNP might be a therapeutic agent in the treatment of vascular dementia in the future. Vascular dementia (VD), which is caused by chronic cerebral hypoperfusion (CCH), hampers the intelligence of an individual, leading to the development of cognitive dysfunction syndrome , 2. Epid Ratna Samphel or 70 Flavors Pearl Pill), a traditional Tibetan medicine  number 134. These regulations are in accordance with the internationally recognized guidelines of National Institute of Health (NIH), New York City, NY, USA.We obtained healthy male Sprague-Dawley rats  from Si Beifu Laboratory Animal Science and Technology Co., Ltd. . The rats were placed in cages; each cage contained a group of five rats. The cages were maintained at room temperature (23 ± 2°C); a relative humidity of 55 ± 5% was maintained in these cages; these rats were subjected to a light-dark cycle of 12 h (light from 7 a.m.–7 p.m.). These rats were providedIn this study, 50 rats were randomly divided into five groups: (1) sham-operated group; (2) 2VO-induced VD model group; (3) RSNP-L (low dose) + 2VO group; (4) RSNP-M (medium dose) + 2VO group; (5) EGB + 2VO group. The rats were kept in cages for a week before the 2VO or sham surgeries. Five days after the surgery, the animals were orally given a definite volume of indicated drugs (5 mL/kg) or distilled water (5 mL/kg) once every day for four weeks; the sham-operated group and the VD model group were given same volume of distilled water (5 mL/kg). The administered doses of RSNP were 70.44 mg/kg (low dose) and 281.76 mg/kg (medium dose); EGB was administered at a dosage of 17.03 mg/kg.The VD model of rats was produced by the bilateral common carotid arteries occlusion (2VO) method . In brieFor determining the spatial learning and memory capability, we carried out Morris water maze (MWM) test on the animals, after completing the four-week drug administration . The expDuring the first five consecutive days, each animal was trained four times per day to find the hidden platform. Every time, they were placed in the maze at the different starting points of different quadrants. All the animals followed the same sequence of starting positions. During each trial, each animal was given 90 s to find and mount on the hidden platform; they were allowed to rest on the platform for 30 s. If the animal did not find the platform within 90 s, it was gently guided onto the platform by the observer. Then, the animal was allowed to rest on the platform for 30 s. In each trial, the escape latency, which was defined as the amount of time spent by the animal in locating and mounting on the platform, was recorded and analyzed using the video analysis system, EthoVision . These trials were called navigation tests. On the sixth day, a probe test was performed. In this test, the platform was removed to assess the spatial learning and memory capability of these animals. The percentage of the swimming time and the distance covered in the target quadrant, where the platform was originally placed, were recorded and analyzed.The cholinergic neurotransmission was determined by detecting the activities of choline acetyltransferase (ChAT) and acetylcholinesterase (AChE); the oxidative stress in the brain was assessed by measuring the activity of superoxide dismutase (SOD) and the level of malondialdehyde (MDA). After the MWM experiment, the animals were sacrificed by overdosed choral hydrate (0.35 g/kg). The brain was immediately removed and placed on an ice-cold sterilized surface. Then, the hippocampi from both sides of the brain were dissected and weighed. The hippocampus of one side was stored at –80°C, and it was later used for performing quantitative polymerase chain reaction (Q-PCR). The tissues of the hippocampus from the other side were homogenized at 4°C with nine times its volume of 0.1 M phosphate buffer (pH = 7.4). About half of the homogenate was centrifuged at 4000 ×g for 15 min; the supernatant was collected for determining the amount of ChAT, AChE, SOD, and MDA, which was using ELISA kits according to the manufacturer's instructions . The remaining homogenate of hippocampus was stored at –80°C for performing Western blot analysis subsequently.μg of protein were denaturalized and separated on 10% sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) gels by electrophoresis. Then, the separated proteins were transferred onto nitrocellulose filter membranes. In Western blotting, the membranes were blocked for one hour with tris-buffered saline (TBS) containing 10% skimmed milk powder and 0.05% of Tween-20. Then, they were incubated for 2 h at 4°C with a primary antibody, which was diluted to 1 : 1000 in the blocking solution. In this experiment, the following primary antibodies were used: Bcl-2 antibody , Bax antibody , or β-actin antibody . The membranes were washed thrice with TBS containing 0.05% Tween-20 before they were incubated for 1.5 h at room temperature with a secondary antibody diluted to 1 : 5000 in the blocking solution. In this experiment, we used goat anti-rabbit IgG  as the secondary antibody. The relative intensity of the detected protein was quantified by gel image analysis system .The expression of apoptotic regulatory protein, B-cell lymphoma-2 (Bcl-2), as well as a decrease in the level of Bcl-2-associated X protein (Bax), was assessed by both Western blotting and Q-PCR. The remaining homogenate was centrifuged at 1600 ×g for 10 min at 4°C; the supernatant was collected and the total supernatant protein was determined by Bradford assay. Samples containing 40 β-actin n the hippocampus, real-time Q-PCR was performed. Total RNA was extracted from the hippocampus tissue using TRIzol reagent . The purity as well as quantity of total RNA was detected by performing UV spectrophotometry using Biophotometer . The integrity of the RNA was examined by performing agarose gels electrophoresis and visualized by an imaging system . The qualified total RNA samples were treated with DNase I, and they were reverse transcribed into cDNA using Oligo(dT)15 primer  and M-MLV Reverse Transcriptase  according to the manufacturer's instruction. Quantitative Q-PCR was performed using synthesized cDNA, specific primers of interested genes  was applied to analyze the escape latencies of different groups in MWM test over a period of five days. Other data were analyzed using one-way ANOVA followed by the least significant difference (LSD) test. All the statistical analyses were performed using SPSS version 20.0 . The results were assumed to be statistically significant when The MWM test was used to observe the effect of RSNP on the spatial learning and memory capability of VD rat model, which was induced by 2VO.F = 924.053, P < 0.05). This indicates that the animals were indeed learning to memorize the position of the platform. There was statistically significant difference among the groups ; the statistically significant difference among the groups depended on the day on which the trial was carried out during the five days of navigation test . Post hoc analysis showed that there was no significant difference in the escape latency of different groups in the first two days (P > 0.05); however, significant difference was detected from day 3 till day 5 of the navigation test (P < 0.05). Compared with the sham-operated group, the model group demonstrated significantly higher escape latency in the last 3 days (P < 0.05). This indicates that a clear learning disability was developed in the VD model group. Compared with the VD model group, both the RSNP-M treatment group, which received RSNP at a medium dose (281.76 mg/kg), and the EGB treatment group had a significantly lower escape latency of VD animals on day 3 to day 5 (P < 0.05), while the group that received RSNP at a low dose (70.44 mg/kg) (RSNP-L) also showed lower escape latency of VD animals on day 3 and day 5 (P < 0.05). Owing to the difference between the two doses of RSNP, the RSNP-M group spent significantly less time in finding the platform than the RSNP-L group on day 3 to day 5 (P < 0.05); there was no significant difference between RSNP-M and EGB groups (P > 0.05). These results indicated that both doses of RSNP improved the learning disability of VD animals, which was induced by 2VO; the medium dose of RSNP probably showed a better effect than the low dosage, and there was no significant difference in the recovery of learning ability of VD animals in RSNP-M group and EGB group.As shown in P < 0.05). This indicates that a memory deficit was induced by 2VO. In the RSNP-M and EGB groups, the VD animals' focus on the target quadrant was significantly better than those of the model group (P < 0.05); however, the memory capacity of RSNP-L group was not better than that of model group. Compared with the RSNP-L group, RSNP-M and EGB groups covered a significantly greater distance in the target quadrant (P < 0.05). Moreover, there was no significant difference between RSNP-M and EGB groups (P > 0.05). The results indicate that only a medium dose of RSNP alleviated the spatial memory deficit, which was previously induced in the experimental animals by 2VO.The probe test was performed one day after the navigation test. The platform was removed before conducting the probe test. The percentage of swimming time and the distance of the target quadrant were used as indicators of memory capacity Figures . CompareIn summary, RSNP treatment significantly improved the impaired learning and memory in the VD animal model. Furthermore, medium doses of RSNP definitely brought about a better improvement.P < 0.05). After being treated with either RSNP (70.44 or 281.76 mg/kg) or EGB, the level of ChAT in the treatment groups was significantly higher than that in the nontreated model group (P < 0.05). However, the level of ChAT was not completely restored to normal levels in the control group (P < 0.05).Since cholinergic neurotransmission was closely associated with the ability of learning and memory, we wanted to determine whether RSNP improved the learning and memory deficits in the VD animals by altering the cholinergic activities in the hippocampus. Therefore, we measured the levels of ChAT and AChE in the hippocampus of VD animals. The results  indicateP < 0.05); however, the AChE activity clearly decreased to normal levels in VD animals when they were treated with either RSNP or EGB (P < 0.05). Compared with the RSNP-L group, the RSNP-M treatment group showed a better recovery (P < 0.05). Furthermore, there was no significant difference between RSNP-M and EGB groups (P > 0.05).Inversely, the content of AChE in the VD model group was significantly higher than that in the control group . After being treated with either RSNP (70.44 or 281.76 mg/kg) or EGB, the activity of total SOD in VD animals increased sharply to become significantly higher than that in the model group (P < 0.05). Furthermore, in RSNP-M treatment group, the activity of SOD was even higher than that in EGB group (P < 0.05).We also wanted to determine the effect of RSNP on oxidative stress, which plays a crucial role in damaging the brain of VD animals. For this purpose, we measured the levels of total SOD and MDA in the hippocampus . The resP < 0.05). Both doses of RSNP could effectively reduce the abnormally higher levels of MDA. Moreover, the abnormally higher MDA levels were also restored to normal levels in EGB group (P < 0.05). No significant difference was observed between RSNP and EGB groups (P > 0.05).The content of MDA in the hippocampus of VD model group was significantly higher than that in the sham-operated control group . Both RSNP and EGB could effectively prevent the 2VO-induced upregulation of Bax and the downregulation of Bcl-2. Therefore, the Bcl-2/Bax ratio was significantly increased (P < 0.05) in VD animals when they were treated with either RSNP or EGB. Compared with RSNP-L group, the RSNP-M and EGB groups had a higher Bcl-2/Bax ratio (P < 0.05). There was no significant difference between RSNP-M and EGB groups (P > 0.05).To determine the effect of RSNP on the apoptosis regulatory factors, Bcl-2 and Bax, in this VD animal model, we used Western blotting analysis to detect the protein expression of Bcl-2 and Bax . Then, aP < 0.05). Interestingly, the RSNP-M group demonstrated a more protective effect than the EGB group, as indicated by the transcript level of Bcl-2 in the VD animals after the treatments (P < 0.05).To verify the protein expression data obtained by Western blotting, we performed real-time Q-PCR to examine the transcript levels of Bcl-2 and Bax Figures . The Q-PIn this study, we used the 2VO method to induce VD in experimental animals. This method was also used to prepare the model of chronic cerebral ischemia , 29 in wAlthough China is a multiethnic country, most people are of the Han Chinese race. In China, there are two major alternative systems of medicine: traditional Chinese medicine and ethnic medicine. Ethnic medicine has been quite effective in treating certain diseases. Traditional Tibetan medicine is one of the representative branches of ethnic medicine, and it has been practiced for many centuries . RSNP, oCentral cholinergic system plays an important role in the spatial learning and memory. Acetylcholine (ACh), the actual neurotransmitter, is synthesized from a reaction between choline and acetyl coenzyme A; this reaction is catalyzed by ChAT in cholinergic synapses. After ACh is released into synaptic cleft, AChE rapidly degrades it to avoid excessive cholinergic neurotransmission. Therefore, ChAT and AChE actively control the homeostasis of cholinergic system . In patiFree radicals are found extensively in organisms. They cause damage to proteins and DNAs, triggering serious diseases –37. TherHippocampus, a crucial structure that governs learning ability and memory, is found to be closely associated with spatial cognitive function. Therefore, it is very vulnerable to apoptosis in patients inflicted with brain ischemia and hypoperfusion. Previous studies have reported that the Bcl-2 protein family plays a vital role in the regulation of apoptosis . Bcl-2 aFor many centuries, RSNP has been widely used in the treatment of chronic cerebrovascular diseases and neural system diseases, but the therapeutic mechanisms of RSNP have not yet been deciphered. Ours was the first study to elucidate the neuroprotective effects of RSNP in the animal model of VD. The protective mechanisms of RSNP probably involve the reduction of oxidative stress, which ultimately leads to a decrease in proapoptotic Bax/Bcl-2 ratio and the restoration of cholinergic neurotransmission. A medium dose of RSNP (281.76 mg/kg) provided neuroprotective effects, which were the same as those offered by EGB. This study proves that RSNP can be considered as a potential therapeutic agent in the treatment of VD.


Now a new birth cohort, the UK’s Life Study, has ambitious plans to enroll tens of thousands of participants and a hope that it will succeed where its counterpart in the USA, the National Children’s Study (NCS) has failed.,Authorized by the Children’s Health Act of 2000, the NCS was a prospective birth cohort study developed to evaluate the effects of environmental exposures on child health and human development.The longitudinal birth cohort design was one of the strengths of the NCS when a panel of experts was convened to evaluate the study and recommend its future.,,,Collectively, European birth cohorts offer an excellent opportunity to investigate the types of questions that the NCS was intended to address. These cohorts bring together several key elements, in terms of sample size, sampling strategy, exposure measures and phenotypic richness, to fill the scientific gap left by the closure of the NCS. Some of the larger cohorts have been hailed as exemplars of efficiency in study development and implementation,http://birthcohorts.net/]—are varied in focus, each offering unique features and strengths. Many have taken the approach of enrolling women in pregnancy or the children shortly after birth. One of the exceptions is the Southampton Women’s Survey (SWS) in the UK,,,,The many European cohorts in existence—descriptions and links to individual study websites at  brings together a number of the major UK birth cohorts as well as the UK Household Longitudinal Study (Understanding Society), to encourage interdisciplinary research, facilitate the use of longitudinal data and share resources and expertise.Many European birth cohorts coordinate efforts with other longitudinal studies, at either the infrastructural or the scientific level, through joint governance, harmonized data collection or metadata or research consortia. For example, several EU-funded projects . Additionally, the cohorts keep the record of their publications and highlight their impact on public health and policy on their websites. Nevertheless, birth cohorts hold considerable untapped potential. Through innovative approaches, such as cross-cohort comparisons, replication studies or large consortia,


Although mortality and health inequalities at birth have increased both geographically and in socioeconomic terms, little is known about inequalities at age 85, the fastest growing sector of the population in Great Britain (GB).To determine whether trends and drivers of inequalities in life expectancy (LE) and disability-free life expectancy (DFLE) at age 85 between 1991 and 2001 are the same as those at birth.DFLE at birth and age 85 for 1991 and 2001 by gender were calculated for each local authority in GB using the Sullivan method. Regression modelling was used to identify area characteristics  that could explain inequalities in LE and DFLE.Similar to values at birth, LE and DFLE at age 85 both increased between 1991 and 2001 (though DFLE increased less than LE) and gaps across local areas widened (and more for DFLE than LE). The significantly greater increases in LE and DFLE at birth for less-deprived compared with more-deprived areas were still partly present at age 85. Considering all factors, inequalities in DFLE at birth were largely driven by social class composition and unemployment rate, but these associations appear to be less influential at age 85.Inequalities between areas in LE and DFLE at birth and age 85 have increased over time though factors explaining inequalities at birth  appear less important for inequalities at age 85. Life expectancy (LE) in Great Britain (GB), as in many other countries, has risen rapidly over the last two decades, from 73.9 in 1981 to about 80.9 in 2011.9With population ageing and the growth in numbers of the very old, we can no longer assume that LE increases will necessarily mean better population health overall. Health expectancies such as disability-free life expectancy (DFLE) are gaining importance for monitoring trends and inequalities in population health, as they combine information on both mortality and morbidity.disability) from a cross-sectional study and alongside a period life table for the same time interval.LE by age, gender and LAs in GB in 1991 and 2001 were calculated using standard abridged period life table methodology, with mid-year population estimates and vital statistics deaths data for 1991 and 2001.Age-specific and sex-specific prevalence rates for disability were computed from the National Census limiting long-term illness (LLTI) question in 1991 and 2001. However, the questions varied somewhat between 1991 and 2001 , resulting in under-reporting in 1991.17supplementary material table S1). We added two further factors measuring rurality and deprivation. For urban–rural gradient , we adapted the sixfold DEFRA classification for Englandsupplementary material table S1). We used the Townsend index of deprivationsupplementary material table S1) and when comparing LAs over time fixed their deprivation quintile membership to 2001 groupings.To explain inequalities, we followed a previous analysissupplementary material figures S1 and S2). To assess changes over time in inequalities in DFLE by deprivation , we fitted models with time and deprivation  and their interactions; if interaction was significant, we inspected time differences within deprivation  groups.To describe inequalities, we present summary statistics  of male and female LE and DFLE at birth and age 85 across LAs. We then ranked LAs on LE and DFLE by year, gender and age (birth and age 85), classified them into area quintiles and visually present these quintiles in a population cartogramTo investigate the relationship between LE and DFLE at birth and age 85, in both 1991 and 2001 as well as area-specific socioeconomic, sociodemographic and environmental factors, we used linear regression models (for LE) and meta-regression models (for DFLE) to allow inclusion of uncertainty around the DFLE estimates,Much has already been published on changes over time in LE and DFLE at birth, but we repeat results briefly for comparison with age 85. Between 1991 and 2001, mean LE at birth increased  with the gender gap decreasing by 0.8 years but increases in DFLE were much smaller , with the gender gap again decreasing, by 0.5 years . Over thSimilar to LE at birth, LE at age 85 also increased between 1991 and 2001  but the percentage changes  were greater than those at birth  . In contsupplementary material figures S1 and S2). For both men and women, there was no significant change over time across the urban–rural gradient  for any of the health outcomes, LE and DFLE at birth and age 85 . Nevertheless, the main effect of urban–rural gradient was significantly associated with health outcomes at birth, with, on average, an increase of one point on the urban–rural scale LE at birth increased by 0.18 years for women and 0.34 years for men while DFLE at birth increased by about half a year for both women and men .In 1991 and 2001, LE and DFLE for women and men at birth showed a distinct northwest to southeast gradient, commonly known as the North-South divide,supplementary material figure S4), with the gradient being steeper for DFLE compared with LE. Moreover, the significant interaction between deprivation and time for both LE at birth and DFLE at birth indicated a strengthening of the associations with deprivation over time. That is, an increase of one deprivation quintile infers a decrease in LE of 0.55 (women) and 0.82 (men) years in 1991, which decreased further in 2001 to 0.69 years (women) and 0.97 years (men). For DFLE, we found a decline of 1.34 (women) and 1.60 (men) years in 1991, which increased further to 1.65 (women) and 1.88 (men) years in 2001. When changes over time within deprivation quintiles were examined, the increase in LE was somewhat larger for more affluent areas  than for the most-deprived areas  and with no significant increase in DFLE at birth in the most-deprived area quintiles (4 and 5) for men and women .With regards to deprivation, for both 1991 and 2001, there was a strong decline in LE and DFLE at birth from the least-deprived towards the most-deprived quintiles for women  and men In contrast, there was little evidence of a relationship between deprivation and LE at age 85, although the relationship with DFLE at age 85 remained as well as the significant interaction between deprivation and time, again suggesting a strengthening of the association between deprivation and DFLE over time on average for both men and women.et alWe first explored the same drivers of inequalities in LE and DFLE that had been considered by Bone When all factors were included, social class, unemployment and retirement migration remained significantly associated with LE and DFLE at birth for men and women in 1991 and 2001 . The multivariable model explained more of the variation in DFLE at birth , than in LE at birth  in both years, more of the variation in 2001 than in 1991, and more of the variation in men than for women .supplementary material tables S3 and S4).In contrast, for LE and DFLE at age 85, patterns of associations across gender and time were much less clear-cut . When coOur comparison of changes over time (between 1991 and 2001) in LE and DFLE values at birth and at age 85 contributes to our understanding of the widening differentials in health within GB identified by the Marmot Review.We found that between 1991 and 2001 and across GB local areas, LE and DFLE at birth and age 85 increased, but LE to a larger extent than DFLE. While the gap across LAs generally increased for both indicators (though the gap in LE at age 85 decreased), the gap in DFLE increased more than that in LE. Patterns of LE and DFLE at birth—northwest southeast divide, urban to rural as well as for the deprivation divide—persisted over time between 1991 and 2001. We observe clear declines in these measures as deprivation increases across LAs and the decline is steeper with DFLE where morbidity is added to mortality. For the very old, the northwest southeast divide is much less apparent and the relationship with deprivation disappears for LE though is still present for DFLE as is the greater gains in less-deprived areas. That gains in LE and DFLE at birth are greater in less-deprived quintiles might result from public health interventions being more successful for the affluent and healthier population or less effective for people in lower socioeconomic status,27All these findings show that LE as a population health indicator produces a more positive picture of population health (at age 85 as well as at birth) than DFLE, confirming other studies.Health inequalities are manifested by various socioeconomic, demographic and environmental variables. We found that social class composition, unemployment rate, retirement potential, population density and ethnic composition explain more variation in DFLE across areas than variation in LE, slightly more of the variation in men than in women, and more of the variation in 2001 than in 1991. However, the relationship of LE and DFLE at birth with unemployment rates changed over time. Unemployment rates were higher and discriminated sharply between areas in 1991, while in 2001 they were lower and less discriminatory. Overall, there is a stronger relationship between social class and deprivation and LE and DFLE in 2001 compared with 1991. Indeed, social class composition is more important in 2001 than in 1991 when unemployment rate was the most important factor.et al 1995Bone Limitations of our study include the need to harmonise the limiting longstanding illness question in 1991 and 2001 and other potential explanatory factors we have not considered. On a national level, harmonised data reproduced Health Survey for England DFLE 1991, which used the 2001 census question. Harmonised data were, as anticipated, lower but differences decreased with age, which is plausible as older people may be less likely to under-report illness in 1991. Education has often been identified as an important factor influencing positively DFLE.Our study suggests inequalities in LE and DFLE at age 85, as those at birth, persist and have increased for DFLE as a result of larger gains in more affluent areas. We also suggest that factors explaining variation in LE at birth between areas may not be the same as those that explain underlying differences in DFLE at birth and in both cases these may not explain inequalities at very old ages. Given the greater disability and illness burden in very late life as well as the continued growth in this age group, monitoring inequalities in health expectancies across local areas at very old ages, as well as at birth, and understanding their drivers will be key to achieve the desired target of health for all.Area variation in health and mortality across Great Britain (GB) local areas is well established as are relationships between deprivation and less good health, and an urban rural gradient.To date, no comparison in disability-free life expectancy (DFLE) over time on a local area level has been done.Published studies have usually focused on at birth and age 65 populations, and not on the very old, a very fast growing segment of the GB population.Drivers for DFLE variation at birth do not explain DFLE variation in the very old.With regards to health improvement, not only are less affluent areas being left behind but worryingly DFLE may even be decreasing at older ages in more-deprived areas.Life expectancy (LE) does not reflect the full extent of health inequality in GB, by using LE as a health indicator, conditions look better than they are and areas in need might not get the support they need.


Relatives play an important role in human reproduction according to evolutionary theories of reproductive behavior, but previous empirical studies show large differences in the effects of kin on fertility outcomes. In our paper we examine the effect of co-resident kin and non-kin on the length of birth intervals over the reproductive life course of Dutch women born between 1842 and 1920. We estimate Cox proportional hazard models for parity progression based on the presence of kin and non-kin in the household while controlling for a large number of individual and community-level characteristics. We find that couples living with their brothers experienced shorter birth intervals whereas couples residing with a widowed father had relatively longer birth intervals. The effects of these types of kin on reproduction were most pronounced up to the birth of the fifth child, but not thereafter. We found no effect for mothers or other types of kin. Co-resident kin and non-kin may play an important role in human reproduction kin on the length of birth intervals over the reproductive life course. Focusing on sequential fertility outcomes over the life courses of the women in our sample allows for a more accurate investigation of kin effects than examining kin influences on total fertility or starting and stopping behavior. We use a rich data source, the Historical Sample of the Netherlands, which enables us to uncover the direction, magnitude, and significance of the effects of co-resident kin and non-kin on the reproductive careers of Dutch women born between 1842 and 1920. We develop our hypotheses on kin effects on fertility using insights from inclusive fitness theory.inclusive fitness, expressed as the number of kin weighted by the relative presence of one’s genes, or alleles  are expected to behave more cooperatively—leading to shorter birth intervals—than genetically more distant relatives . In addition, uncertainty about the degree or nonexistence of genetic relatedness lowers the likelihood of cooperative behavior. The “confidence of paternity hypothesis” predicts that investments in grandchildren are lower if they are related through sons than through daughters . The HSN is a representative, nationwide random sample of about 78,000 individuals  born in the Netherlands between 1812 and 1922  who entered a first marriage and for whom complete information is available about (1) the couple’s reproductive career until the woman is 50 years old and the husband is still alive and (2) the presence of kin and non-kin in the household. We focus only on the waiting time from the first until the second marital birth and on subsequent birth intervals but exclude the interval between marriage and first birth. The interval between marriage and first birth was often relatively short and in many cases not affected by kin presence, but instead by cultural norms which prescribed that the conception of the first child should follow not too long after marriage : (1) parents; 2) siblings; (3) other relatives, such as cousins, aunts, and uncles; and (4) non-kin . Since couples may live only part of their reproductive lives together with others, all kin and non-kin are coded as time-varying dummy variables with value 0 (not present) or 1 (at least one person of that particular kin type is present in the household of the couple). Table  siblingsnuclear family systems. The southeastern provinces are coded as stem family systems because of the occurrence of impartible inheritance, or Anerbenrecht, and the specific customs with regard to co-residence in which young couples “married in” and became part of the parental household. The remaining provinces are coded as intermediate family systems  denotes the hazard rate, or the chance of having a next birth, in period t for the specified vector of time-varying covariates, h0(t) is a non-negative and unspecified baseline hazard function that varies arbitrarily over time and is not dependent on the covariates Xj, and βx is a vector of unknown regression coefficients to be estimated from the data using maximum likelihood (Cleves et al. t, but the magnitude of the hazard is multiplied by the exponentiated regression coefficient of each group. Time is measured in months, and a coefficient larger than zero denotes a higher chance of giving birth in period t, or in other words, a shorter birth interval.We use an event history approach to examine whether the lengths of women’s closed birth intervals were associated with the presence of kin and non-kin in their households (Cleves et al. t, although the effect of religion is left unspecified. For parity six and up, we estimate one model for all births after the fifth birth and control for net parity, which is the total number of living children at time t. In order to ensure proportionality of hazards in this model, we included additional time-varying effects for marriage duration and the death of the previous infant if they survived until they were at least 8 months of age.The Cox model assumes that the estimated hazard ratios are proportional to each other. The assumption of proportionality was tested by examining the Schoenfeld residuals and the proportionality of the log-log plot of the survival rate against the log of time for each variable. These pre-analysis tests indicated that the baseline hazard should be allowed to vary between religions for all models, which ensures that we can still provide reliable estimates for the effects of kin on the hazard rate of childbirth in the period Another important assumption of the Cox model is that the risk of parity progression in the sample is randomly distributed across observations. However, since birth intervals are by their nature clustered on the level of the couple, it is likely that parity progression risks are not completely random and the hazard ratio may thus be conditional on the individual frailty of each couple (Cleves et al. Table Our results indicate that for later-order births, from parity six and up, co-residence with kin was not significantly associated with longer or shorter birth intervals. For lower parities, living with both parents of either the husband or the wife did not affect the time until next birth, although living with the husband’s parents had a small delaying effect on the birth of the fourth child. In contrast, living with a widowed father of either spouse significantly reduced parity transition rates. The birth intervals of women living with a widowed father were about twice as long as birth intervals of women who did not live with a widowed father.The length of time between births was at least 20% shorter for women who lived with at least one brother or brother-in-law, compared with women who did not live with a brother or brother-in-law in the same household. The positive effect of the presence of the husband’s brother was particularly high for women experiencing the transition from the third to the fourth child, for whom the parity transition rate was almost twice as large as for other parities. Strikingly, in contrast to living with brothers, living with sisters of either of the spouses did not significantly affect parity transition rates.Other types of co-resident kin, such as aunts or uncles, had no systematic effect on the duration of the transition to the next birth. The presence of non-kin did affect birth intervals, but their effect was not stable over the reproductive life course. The presence of servants affected only the waiting time until the birth of the third child and the birth intervals of fifth and later-order children. Co-resident boarders and lodgers had a significant delaying effect on the birth interval for the third parity, but shortened the birth interval for the fourth and fifth parity. Keeping in mind the low number of observations of non-kin in our sample, these findings should be interpreted with care.The time until next birth was longer for couples who were married for a longer period of time, as was expected. However, for women who had at least six children, we observe that parity transition rates increased after 18 years of marriage compared with women who were married for less than 18 years. Crude parity indicates the total number of children that have been born to a woman. As would be expected, women who had experienced a larger number of pregnancies had shorter intervals between births. Similar to findings by Van Bavel and Kok , 2010, pIn human behavior, as in the behavior of other animals, the provision of support to genetically related kin is expected to confer an indirect advantage in terms of inclusive fitness Hamilton . It follUsing continuous-time data on household composition as a proxy for cooperative behavior, we find that co-resident kin had different effects on fertility at different stages of the reproductive life span of women. The effects of kin were not significant for higher parities. This finding may provide a partial explanation for the variations in kin effects on fertility that have been observed in the literature in which only measures of complete fertility outcomes are taken into account (see Sear and Coall Our findings suggest that co-resident kin did not affect reproductive outcomes of Dutch women in a uniform way. In contrast to other empirical findings, we find that parity progression rates were not significantly affected by the presence of widowed mothers or both parents of either spouse (Hawkes et al. Our study contributes to the growing literature on empirical approaches to evolutionary theories of demographic behavior. The findings presented here raise further questions concerning the role and position of kin members within the household as well as the extent of their cooperative behavior, such as provisioning of care or contributions to household income, which is difficult to infer from kin presence alone (see, e.g., Schaffnit and Sear Inclusive fitness theory enables us to understand the motives underlying the behavior of household members toward genetically related others, but actual demographic outcomes are determined by the specific historical, social, economic, and spatial conditions of the household, as well as maternal health and the extent of cooperative behavior of kin that enables women to give birth. Future research on the interaction between wealth and kin influence, or differences in cultural norms concerning kinship and reproduction, which lie beyond the scope of this study, may further illuminate variations in the influence of kin on reproductive outcomes.


We show that HSV-1 dl1403 virions lack detectable levels of envelope protein gC, and that gC is not synthesized in infected cells. Sequencing of the gC gene from HSV-1 dl1403 revealed a single amino acid deletion that results in a frameshift mutation. The HSV-1 dl1403 gC gene is predicted to encode a polypeptide consisting of the original 62 N-terminal amino acids of the gC protein followed by 112 irrelevant, non-gC residues. The mutation was also present in a rescuant virus and in two dl1403-derived viruses, D8 and FXE, but absent from the parental 17+, suggesting that the mutation was introduced during the construction of the dl1403 virus, and not as a result of passage in culture.Herpes simplex virus 1 (HSV-1) ICP0 is a multi-functional phosphoprotein expressed with immediate early kinetics. An ICP0 deletion mutant, HSV-1  Alphaherpesvirinae subfamily that causes lifelong latent infections in humans. Upon infection of the host cell, HSV-1, like all herpesviruses, executes a cascade of temporally regulated gene expression. Infected cell protein (ICP0) is an HSV-1 immediate early (IE) phosphoprotein that acts as a promiscuous transactivator of viral and cellular genes, and is required for low multiplicity infection  of 1) was added. Cells were incubated in the constant presence of agent for 7 h. 0.5% Nonidet P-40 (Sigma) cell lysates were prepared, chlorophenol red-beta-D-galactopyranoside  was added, and the beta-galactosidase activity was read at 595 nm with an ELx808 microtiter plate reader . The MG132 treatments tested had no adverse effect on cell viability as measured by trypan blue exclusion [Confluent CHO-nectin-1 cell monolayers grown in 96-well dishes were treated with culture medium containing MG132 for 15 min at 37°C. HSV-1 KOS, 7134, gC∆2–3, 17+ or xclusion . Beta-gaxclusion . Mean redl1403, KOS, or gC∆2–3 (100 PFU per well) was mixed with indicated heparin concentrations in carbonate-free DMEM containing 5 mM HEPES and 0.2% BSA. Chilled inocula were added to cells and incubated at 4˚C on ice for 1 hr to allow virus binding to the cell surface. Cultures were washed thrice with PBS, and then incubated at 37˚C for 24 hr. Plaque formation was detected by immunoperoxidase staining with anti-HSV-1 polyclonal antibody HR50  [Confluent Vero cells were pre-chilled on ice. HSV-1 17+, ustries) . Plaque HEL cells were infected with the indicated viruses for 24 hr (MOI of 10). Cells and supernatant media were harvested, freeze-thawed three times, and then titered on U2OS cells in the presence of hexamethylene bisacetamide (HMBA) and 2% human serum. After three days, cells were fixed with methanol, stained with Giemsa (Sigma), and then plaques were counted.dl1403 virions in the absence of ICP0 [dl1403 virions were analyzed by SDS-PAGE and Western blotting with polyclonal antibody to gC. Interestingly, gC was not detectable in dl1403 virions  present in the dl1403-infected cells (dl1403 (data not shown). Thus, the results suggest that gC was undetectable in dl1403 virions . Therefore, the possibility that HSV-1 dl1403 contained a previously unrecognized mutation in its gC gene was investigated.We next determined whether ed cells . Lysatesed cells . gC was  virions  because dl1403 revealed a single nucleotide deletion of C186 relative to the wild type parent 17+, which results in a frameshift . Thus, in addition to not expressing ICP0, HSV-1 dl1403 fails to express a detectable gC protein likely due to these mutations.Sequencing the gC gene from HSV-1 ameshift . The newno acids . The seqno acids , which cno acids . The dl1dl1403R, a dl1403 virus that was rescued with the wild type ICP0 gene, and from FXE and D8, ICP0 mutants derived from dl1403. The gC gene from each of these dl1403-derived viruses contained the same substitution and frameshift mutations that were detected in all preparations of dl1403 tested . Together, the results suggest that dl1403 virions and infected cells lack detectable levels of gC, due to the identified mutations in the dl1403 gC gene.Despite the detected mutations in the gC gene, we addressed the formal possibility that HSV-1 dl1403 was refractory to inhibition [dl1403 lacks gC in addition to ICP0, we assessed directly whether gC contributes to the proteasome-dependence of HSV-1 entry. The effect of MG132 on the entry of a gC-null (ICP0+) virus, HSV-1 gC∆2–3, was determined. MG132 inhibited the entry of gC∆2–3 in a concentration-dependent manner as measured by beta-galactosidase reporter gene expression, similar to the wild type virus (KOS) from which it was derived (dl1403; ICP0 present in the virion tegument layer regulates the proteasome-dependent delivery of incoming viral capsids to the nuclear pore complex . The enthibition . Since d derived . The hig dl1403;  or lacke dl1403; , were redl1403. HSV-1 dl1403 was inhibited by heparin to a lesser extent than the gC-containing parental virus 17+ (dl1403 behaves similarly to a gC-null virus in an assay of biological function.Envelope gC is the principal mediator of HSV-1 attachment to cell surface glycosaminoglycans, such as heparan sulfate ,54,55. Iirus 17+ . Likewisirus 17+ , consistdl1403, marker rescue experiments showed that restoration of the ICP0 sequence returned viral replication to wild type levels in cultured cells [dl1403. Similarly, when grown on HEL fibroblasts and titered on U2OS cells, as previously described [dl1403, n212 and 7134 all reached similar titers (dl1403 is not more attenuated than other ICP0-null viruses with intact gC expression. Interestingly, all three of these viruses reach higher titers than what is observed for 7910, which may be a strain-specific difference.Upon the initial generation of escribed , we founr titers . This sudl1403 virions and strains derived from it, such as D8 and FXE, lack gC, and dl1403-infected cells fail to synthesize gC, likely due to detected mutations in the gC gene. Our results illustrate the potential for secondary mutations in the construction and evaluation of HSV-1 mutant strains. In general, it is desirable to construct and examine the same mutations in multiple wild type strains. Although our stocks of the parental 17+ strain lack the gC mutations, it is possible that the stock of 17+ from which dl1403 was originally derived was the original source of the mutations. Notably, laboratory strains of HSV-1 considered to be wild type also contain mutations in their genomes [In summary, HSV-1  genomes ,59,60,61dl1403 restores the virus to wild type phenotype in cell culture assays that test ICP0 functions [dl1403 to wild type in cell culture [dl1403 in mouse models have also effectively used an ICP0 rescuant as a control [in vivo. Indeed, in some animal models, gC-null viruses are highly attenuated [dl1403, and the marker rescue virus R4 in mice indicated that R4 replicated similarly to 17 syn, although it did show some evidence of mild attenuation compared to the wild type virus [dl1403 may have produced minor additional defects in replication in vivo, the effect of the loss of ICP0 is much greater. Along with the present study, this also highlights the importance of using rescuants as controls in experiments using mutant HSV-1 strains. Phenotypes of HSV-1 dl1403 attributable to the absence of gC, but unrelated to ICP0 function, such as enhanced resistance to heparin (dl1403-derived viruses including ICP0 rescuants.Several strains of HSV-1 that lack gC have been identified ,63,64,65unctions . For exa control ,70. Althtenuated ,71,72,73tenuated ,75,76,77 heparin , are alsdl1403, dl1403R, D8 and FXE are widely used viruses. Thus, our finding that these strains contain a secondary mutation in gC impacts a large number of studies. We are currently in the process of creating repaired versions of dl1403, D8 and FXE with intact gC expression. Our findings suggest that caution is necessary in using the current viruses and also suggest that previous studies should be interpreted with the absence of both the ICP0 and gC genes in mind.HSV-1