the development of strategies to preserve 
 functional capacity of the geriatric population is therefore of paramount importance in 
 improving elderly quality of life and reducing health care costs2 . there is growing evidence that the prevalence of 
 malnutrition in elderly people is increasing3 . malnutrition in the elderly was often associated with negative 
 outcomes , for example , an increased risk of falling , anemia , immune dysregulation , impaired 
 cognitive status , reduced muscle function , and increased morbidity and mortality3,4,5,6 . it 
 is also known that hospitalized elderly patients are at high risk for malnutrition;7 the prevalence of malnourished elderly is 
 high in rehabilitative settings8 and 
 malnutrition is associated with poor rehabilitative outcomes9 , 10 and worse functional 
 performance11 . therefore , it is 
 important to assess nutritional status in elderly patients in these settings in order to 
 deliver them appropriate care . the mini nutritional 
 assessment ( mna ) is a validated and commonly- used tool . it has high sensitivity and 
 specificity and is effective for evaluating the nutritional status of elderly persons living 
 in different settings12 , 13 . the mna consists of 18 items covering four dimensions : anthropometry , dietary assessment , 
 global assessment , and self - evaluation . the first 6 items of the full mna constitute the mna 
 short - form ( mna - sf ) . mna - sf is a screening test used for identifying those who are 
 potentially at risk for malnutrition . those who are identified as  at risk for malnutrition  
 are further assessed with the full mna14 . usually the mna - sf correctly predicts the result of the full mna12 , 15 . several 
 studies have shown that the mna score is associated with functional status and is able to 
 predict the functional decline16 of older 
 adults living in a community17 as well as 
 in institutions18 and acute inpatient 
 wards19 . there is little data on the relationship between nutritional status and functional 
 performance in elderly inpatients in rehabilitative hospitals . the present study aims to 
 examine the relationship between nutritional status evaluated with mna - sf , and functional 
 status measured by the barthel index ( bi ) in a cohort of elderly inpatients in a 
 rehabilitative hospital . our overarching goals were the following : 1 ) providing support for 
 the hypothesis that in elderly rehabilitative inpatients , nutritional status and functional 
 performance are positively related , and 2 ) showing that functional and nutritional status 
 decline with aging . in the present cross - sectional study , we observed the relationship between barthel index 
 ( bi ) and mini nutritional assessment short form ( mna - sf ) in a cohort of elderly inpatients 
 in a rehabilitative center . informed consent was obtained from all participants and 
 procedures were conducted according to the declaration of helsinki . the local ethical 
 committee of the rehabilitation center approved the protocol used in the study . the initial sample consisted of 344 patients who were admitted at the general 
 rehabilitation center . the inclusion criteria were as follows : 1 ) patients between 65 and 
 100  years of age admitted at the general rehabilitation center were included ; and 2 ) the 
 ability to perform functional tests was required . the exclusion criterion consisted of the 
 presence of any illness that could represent a risk to the subject s health during the 
 functional assessment . thus , two groups of patients were excluded from the items of the bi 
 related to mobility ( ambulation or transfers ) : those medically prohibited from walking or 
 standing , and those reporting dizziness or altered vestibular function during the initial 
 physical examination or immediately prior to the functional assessment . bedridden patients were also excluded . nutritional status : nutritional status was measured using the mini nutritional assessment 
 short form ( mna - sf ) , a valuable tool for providing rapid and reliable nutritional screening 
 in elderly patients , derived from the mna . mna is a tool that evaluates the individual s 
 nutritional status with 18 questions in four areas ( basic anthropometrics , dietary intake , 
 global indicators , and self - assessed health status ) . the mna is a practical , noninvasive , 
 and cost - effective instrument to assess nutritional status in older people14 . the mna is considered a screening and 
 assessment tool with a reliable scale and clearly - defined thresholds , usable by health care 
 professionals12 . the mna short form , a 
 subset of the full mna , may come to replace the full mna7 as it is sensitive , specific , and accurate in identifying patients 
 at risk for malnutrition14 . it is adequate in assessing nutrition status in hospitalized elderly patients8 and it is also able to predict hospital 
 readmission and mortality10 . functional status : the bi is one of the most widely used measures of self - care performance . 
 among all such instruments , the bi has been regarded as the best in terms of sensitivity , 
 simplicity , communicability , scalability , and ease of scoring20 , 21 . the bi was developed as a measure of disability in patients with neuromuscular and 
 musculoskeletal conditions receiving inpatient rehabilitation22 . the bi has been associated with other scales , for example , the 
 frenchay activities index ( fai ) , the nottingham extended activities of daily living 
 ( neadl)23 , and the functional 
 independence measure ( fim)24 . the items can be 
 divided into a group that is related to self - care ( feeding , grooming , bathing , dressing , 
 bowel and bladder care , and toilet use ) and a group related to mobility ( ambulation , 
 transfers , and stair climbing ) . the score ranges from zero , representing a totally dependent 
 bedridden state , to one hundred , which represents the complete independence23 . prior to 
 participation in the study , all patients signed an informed consent form ( icf ) . all 
 underwent a comprehensive assessment , which consisted of two visits . during the first visit , the patient s history was recorded , a physical examination was performed and the patient 
 signed the icf . during the second visit 24 hours later , a functional assessment was 
 performed using bi and mna - sf . the 
 kolmogorov - smirnov ( k - s ) one - sample tests were initially used to assess the normality of the 
 distributions . next , we categorized patients into three age groups : 6574 yrs , 7584 yrs , 
 and > 85 yr . we used kruskal - wallis h ( k - w ) tests and mann - whitney u ( m - w ) tests to assess 
 differences among the age groups on the mna - sf and bi . mna - sf scores ranged from 0 to 
 14 , and values below a threshold of 12 were used to identify at - risk patients . bi cutoff scores were defined as 45 out of 100 for 
 better functional status and < 45 out of 100 for worse25 . kendall tau - b ( t ) tests were used to evaluate the relationship 
 between bi and mna - sf , and chi - squared ( 2 ) tests were 
 used to compare proportions between age groups . finally , spearman s rho ( rs ) test was used 
 to analyze the association between bi and items within the mna - sf . three hundred forty - four participants ( mean  sd 77.7  6.8  years ; 59.3% female ) met all 
 the inclusion criteria and agreed to participate . no significant differences in the mean age 
 were observed between men ( mean  sd : 76.5 6.4  years ) and women ( mean  sd : 78.5 
 7.0  years ) ( p = 0.51 ) . analyses of kendall s correlation coefficients indicated significant associations between 
 age distribution and the scores obtained with the bi ( t = 0.326 , p < 0.001 ) and mna - sf 
 ( t = 0.303 , p < 0.001 ) . follow - up kruskal - wallis testing indicated significant lowest 
 scores with increased age for the bi ( k - w :  = 139.8 , gl = 92 , p < 0.001 ) and 
 mna - sf ( k - w :  = 52.6 , gl = 12 , p < 0.001 ) . in table 1table 1.age affects functional statusassessment age% of subjectstotalinstrumentsgroupper score rangebarthel index04445100657423 ( 19.7%)94 ( 80.3%)117 ( 34%)*758474 ( 44.8%)91 ( 55.2%)165 ( 48%)>8547 ( 75.8%)15 ( 24.2%)62 ( 18%)mna - sf0111214657459 ( 50.4%)58 ( 49.6%)117 ( 34%)*7584128 ( 77.6%)37 ( 22.4%)165 ( 48%)>8556 ( 90.3%)6 ( 9.7%)62 ( 18% ) * indicates significant difference at the level of p<0.001 . mna - sf : mini nutritional assessment short form , barthel index scores and mna - sf scores are reported according to age ; with 
 aging , the number of subjects with better functional status ( barthel index 45100 ) and 
 normal nutritional status ( mna - sf 1214 ) decreases . mna - sf : mini nutritional assessment short form the analysis of the correlation coefficients obtained for the various assessment items used 
 in the functional evaluation of the elderly indicated that the bi scores presented 
 significant correlations with some items of the mna - sf ( table 2table 2.spearmans rank correlation coefficients between the mna - sf score and the barthel 
 index scoresbasal metabolic dataspearman s r barthel - item - a 0.262*barthel - item - b0.247*barthel - item - c0.439*barthel - item - d0.001barthel - item - e0.403*barthel - item - f0.142*mna - sf : mini nutritional assessment short form . * finally , subjects with better functional status ( barthel index 45100 ) tend 
 to have normal nutritional status ( mna - sf 1214 ) , while subjects with worse functional 
 status ( barthel index 044 ) are more likely to be malnourished or at risk for malnutrition 
 ( mna - sf 011 ) , ( =357.956 , p<0.001 ) . the primary finding of the current study is that nutritional status is associated with 
 functional status in a cohort of elderly inpatients in a rehabilitative center . indeed , 
 mna - sf scores and bi scores are positively associated , and it is shown that both nutritional 
 and functional status worsen with age . mna - sf is also a 
 tool capable of predicting functional disability in the elderly . it has been demonstrated to 
 be a good predictor of functional status in institutionalized elderly at risk of 
 malnutrition27 . a low mna - sf score has 
 also been related to incident disability in older adults28 . moreover , malnutrition identified by the mna and mna - sf has been 
 associated with functional status in different settings , for example in elderly persons 
 living in communities , institutions27 , 
 acute care hospitals19 , 29 , and in those undergoing ambulatory rehabilitation26 , 30 . we verified the hypothesis that the association between malnutrition 
 and functional status also exists for patients hospitalized in a rehabilitative department . there are several reasons for this : reduced appetite 
 and energy expenditure , fluid and electrolyte imbalance , altered levels of cytokines and 
 hormones , delayed gastric emptying , and an impaired sense of smell and taste . moreover , 
 pathologic changes of aging such as chronic disease , depression , cognitive impairment , 
 multiple morbidities , and polypharmacy play an important role in the complex etiology of 
 malnutrition in the elderly3 . inadequate diet and malnutrition32 results from the lack of functional 
 autonomy , impairing the ability to look after oneself , to prepare food , and to eat properly . impaired functional status increases vulnerability and may affect food consumption as well 
 as the quality and the quantity of food consumed29 . furthermore , nutritional status becomes particularly critical in 
 patients with cognitive impairments , given that these individuals become progressively more 
 dependent on others to perform the basic activities of daily life , such as feeding 
 oneself31 . nutritional status assessment is crucial in rehabilitative setting , as there is an high 
 prevalence of malnutrition in rehabilitative department33 ; it has also been demonstrated that rehabilitative 
 outcomes are influenced by nutritional status26 . in their study , charlton et al.7 
 concluded that the majority of older patients in the rehabilitation setting are 
 nutritionally compromised and that this adversely influences health outcomes , for example 
 length of hospital stay . it has been shown that malnutrition correlates with 
 pressure sores , infections , and non - infectious complications34 . the elderly are often transferred to rehabilitation units from acute - care departments , 
 where they may have developed malnutrition as a result of their illness , of certain 
 treatments , or of hospital - associated deconditioning . therefore , upon admission , prompt and 
 careful evaluation of malnutrition risk is crucial in order to achieve positive 
 rehabilitative outcomes and to reduce the economic burden of malnutrition in this growing 
 segment of the population35 . the impact of malnutrition on rehabilitative outcomes carries with it a biological 
 assumption : malnutrition has a direct effects on both muscular action and the activity of 
 the nervous system36 . therefore , 
 malnutrition may affect both gait and balance as a result of muscle weakness and the 
 inability of the brain to deal with the associated sensorimotor and cognitive demands31 . routine functional evaluation and 
 nutritional screening is recommended for all older patients admitted to the hospital , 
 especially in a rehabilitation setting , in order to identify patients with functional 
 disability and at risk of malnutrition35 . this study reinforces the importance of the mna - sf as a tool to assess the nutritional 
 status of the elderly hospitalized in a rehabilitative department . the association between nutrition and functional level prompts us to deeply evaluate 
 nutritional status in elderly patients with functional disability . nutritional status can be 
 an important predictor of disability in hospitalized patients , and should be addressed by 
 interventional strategies . the prompt identification of hospitalized elderly patients at risk for malnutrition makes 
 it possible to set up specific nutritional treatments . more studies are needed to better understand the mechanism of 
 association between nutritional status and functional status in elderly . at this point , the 
 relationship between nutritional intervention and health status in the elderly is still not 
 clear . the main limitations of this study were the lack of data on indicators of physical 
 function , which limited the interpretation of the impact of nutritional status on physical 
 functional ability . in addition , dietary intake was not assessed , and therefore reasons for 
 malnutrition could not be identified with certainty . in conclusion , this study reinforces the concept that nutritional status is associated with 
 functional status in elderly patients hospitalized in a rehabilitative department , and that 
 both nutritional and functional status deteriorate with age . in order to understand whether 
 early identification of malnutrition might help to reduce disability in the elderly , further 
 research into the effect of nutritional intervention on disability