poor sleep quality and sleep disorders  particularly insomnia , osa , and rls  are common problems in people with type 2 diabetes ( 3,6,8,12,13 ) . sleep quality provides a global subjective assessment of sleep that includes features such as sleep duration , time needed to initiate sleep ( i.e. , sleep latency ) , percentage of time asleep while in bed ( i.e. , sleep efficacy ) , sleep disturbances , and general satisfaction with sleep ( 14 ) . studies utilizing the pittsburgh sleep quality index ( psqi ) ( 14 ) indicate that people with type 2 diabetes have poor sleep quality ( mean psqi global scores 6.38.3 ) , with 4971% identified as poor sleepers according to the suggested cutoff for the psqi global score ( psqi > 5 ) ( 8,1517 ) . data from self - reports and polysomnography suggest that people with type 2 diabetes have an average sleep duration of 6 hours ( 15,18 ) . insomnia can be defined as a symptom comprising sleep - specific complaints such as difficulty initiating and maintaining sleep , waking too early , and difficulty returning to sleep , or as nonrestorative sleep , or as a disorder denoting sleep and daytime symptoms , including fatigue , irritability , and decreased concentration . insomnia may be transient , but it can become a chronic problem if perpetuated by maladaptive sleep habits and dysfunctional beliefs and attitudes about sleep . the prevalence of insomnia is significantly higher among people with type 2 diabetes than among those without type 2 diabetes , even after accounting for age and sex ( 12,19 ) . with regard to specific insomnia symptoms , 817% of people with type 2 diabetes report difficulty falling asleep , 2340% have difficulty staying asleep , and 2643% report difficulty both in initiating and maintaining sleep ( 7,12 ) . rls is a condition that negatively affects sleep and is prevalent in people with type 2 diabetes ( 13 ) . rls has a higher prevalence in people with type 2 diabetes than in the general population . symptoms of rls include an uncomfortable urge to move the legs or unpleasant sensations that worsen with rest or inactivity and increase in intensity during the evening and at night ; movement brings partial or total relief of these negative sensations ( 20 ) . frequently , rls symptoms result in a secondary insomnia , with disturbance of the individual s ability to initiate and maintain sleep . osa is a common sleep disorder characterized by recurrent occurrences of upper airway collapse during sleep that produces apneas ( cessation of airflow for at least 10 seconds ) and hypopneas ( decreased airflow by 50% that is associated with an oxygen desaturation ) . there is a transient arousal from sleep that is associated with the termination of apneas and hypopneas . the most common signs of osa are loud snoring , gasping , or witnessed pauses in breathing , as well as excessive daytime sleepiness . an apnea - hypopnea index ( ahi ) , which is the mean number of apnea and hypopnea episodes per hour of sleep , is obtained during overnight polysomnography and used to diagnose osa . the following thresholds are used to classify the severity of osa : normal ( ahi < 5 ) , mild ( ahi 514.9 ) , moderate ( ahi 1530 ) , and severe ( ahi 30 ) . osa often goes undiagnosed among people with type 2 diabetes , such that only 18% of those being managed in primary care clinics received an osa diagnosis ( 5 ) . overweight and obesity are not only risk factors for type 2 diabetes , but also major risk factors for osa ( 4 ) . the prevalence of moderate to severe osa among people with type 2 diabetes is high , with rates ranging from 24 to 36% ( 6,8,9,21 ) , and is significantly greater than in those without type 2 diabetes ( 5,9,21 ) . older age , male sex , and obesity are the strongest risk factors for osa ( 3,6,10,22 ) . in an epidemiological study of obese people with type 2 diabetes , 87% were found to have osa , with 30.5% having moderate osa and 23% having severe osa ( 4 ) . quality of life , according to the world health organization ( 23 ) , encompasses physical and psychological health , functional status , and beliefs , values , and relationships . studies examining the association between sleep and quality of life have primarily examined aspects of health - related quality of life ( hrqol ) . a large study ( n = 19,711 ; 5,161 with insomnia and 14,550 without insomnia ) found that people with insomnia had significantly ( p < 0.01 ) lower physical hrqol , mental hrqol , and work productivity than people without insomnia ( 24 ) . sleep disorders such insomnia , rls , and osa and poor sleep quality have all been associated with decreased quality of life in people with diabetes ( 8,2527 ) . a study of individuals with type 2 diabetes ( n = 300 ) examined the relationship between sleep quality , hrqol , and diabetes - related quality of life ( 8) . people with poor sleep quality ( psqi > 5 ) had significantly lower scores on hrqol ( sf-36 mental component summary and subscores [ social functioning , emotional role , and mental health ] and sf-36 physical component summary and subscores [ physical functioning , physical role , bodily pain , general health , and vitality ] ) and on diabetes quality of life ( dqol ) questionnaire total score and subscores ( dqol satisfaction , dqol impact , and dqol diabetes - related worry ; all p < 0.002 ) . similar findings were found in another study of patients ( n = 124 ) with comorbid rls and type 2 diabetes ; rls was an independent risk factor for lower scores on the sf-36 mental component summary score and the vitality , mental health , and role limitations subscores related to emotional health problems ( 28 ) . although the association between decreased quality of life and sleep disturbances is well established , the effect of impaired sleep on aspects of diabetes self - care behaviors ( e.g. , physical activity , diet choices , and medication adherence ) is less certain . in a descriptive correlational study of 107 adults with type 2 diabetes ( 29 ) , increased subjective daytime sleepiness ( epworth sleepiness scale ) ( 30 ) was significantly associated with worse self - care and control problems . additionally , impaired sleep quality ( psqi ) ( 14 ) was significantly associated with lower scores on diabetes glycemic control , a worse attitude toward activities required for optimal management of diabetes , decreased positive attitude toward feeling able to manage diabetes , lower self - reported adherence to good self - care behaviors , and decreased adherence to good diet choices ( all p < 0.05 ) . maintaining a physically active lifestyle is important in the prevention of diabetes . preliminary evidence suggests that impaired sleep has a negative impact on physical activity in people with diabetes . data from the 20052006 national health and nutrition examination survey found that impaired sleep was common ( 26% with 6 hours of sleep per night ; 17% with daytime sleepiness ) among people with prediabetes ( n = 866 ) ( 31 ) . a regression analysis found higher levels of insomnia symptoms to be a significant predicator of objectively measured steps after controlling for age , bmi , self - reported health , and education ( p = 0.026 ) . results from several studies indicate that inadequate sleep , poor sleep quality , and sleep disorders such as osa are associated with decreased objective physical activity and subjective vigor in people with diabetes ( 3235 ) . furthermore , data from a small intervention study ( n = 23 ) suggest that treatment of osa without assistance in improving activity in people with type 2 diabetes who have a sedentary lifestyle may be insufficient to change established behaviors ( 35 ) . there is a lack of information on the effect of impaired sleep on medication adherence in people with diabetes . however , data from an observational study of older adults ( n = 897 , 37% [ n = 338 ] with diabetes ) found that self - reported medication nonadherence according to the 4-item morisky medication adherence scale ( 36 ) was increased by almost 50% in individuals with sleep disturbances ( odds ratio [ or ] 1.48 , 95% ci 1.121.96 ) ( 37 ) . these results agree with a prospective study on the effect of impaired sleep on medication nonadherence ; among heart failure patients ( n = 280 ) , those with impaired sleep quality were significantly more likely to be nonadherent to their medication regimen ( p = 0.035 ) ( 38 ) . in addition to impeding diabetes self - management , sleep disturbances have also been found to negatively affect psychological well - being and daily functioning . in a sample of 39 adults with type 2 diabetes with and without rls , decreased sleep quality was associated with more fatigue and depression symptoms , and these associations persisted when adjusting for rls status ( 13 ) . data from another study of people with type 2 diabetes found that those with rls had more than three times the depression risk ( or 3.21 , 95% ci 1.0711.23 ) of those without rls ( 28 ) . sleep quality has been found to have an indirect effect on the relationship between psychological distress ( depression and anxiety symptoms ) and diabetes - related quality of life ( 39 ) . data from a recent study ( 26 ) suggest that poor sleep quality in adults with type 2 diabetes is associated with decreased functional outcomes evaluated by the functional outcomes of sleep questionnaire ( fosq ) , including the capacity to realize a lifestyle that is active and productive , maintain social relationships with friends and family , sustain vigilance to required tasks , and continue healthy intimate sexual relationships , even after controlling for age , race , bmi , marital status , and hrqol . poor sleep quality , insomnia symptoms , osa , and sleep disturbances such as pain , rls symptoms , and nocturia are associated with increased odds of frequent daytime sleepiness among adults with type 2 diabetes . those with untreated osa may experience daytime sleepiness resulting from fragmented sleep due to arousals associated with termination of apneas and hypopneas . compared to age- and sex - matched controls without type 2 diabetes , excessive daytime sleepiness , defined as an epworth sleepiness scale score 12 , was significantly more frequent among those with type 2 diabetes ( 2.1 vs. 15.5% , p = 0.02 ) ( 12 ) . in a sample of 44 male veterans with type 2 diabetes , those with daytime sleepiness had significantly lower functional outcomes based on the fosq total score and all fosq subscale scores ( 40 ) . data from studies of normoglycemic patients with osa found that functional outcomes ( fosq scores ) ( 41 ) are improved with continuous positive air pressure ( cpap ) treatment if patients wear their cpap devices for 6 hours per night ( 42,43 ) . furthermore , daytime sleepiness was associated with significantly higher levels of stress and physical and mental exhaustion ( 40 ) . a secondary analysis of data from the 2003 sleep in america poll found that adults with type 2 diabetes and daytime sleepiness had lower self - rated health and greater physical functioning impairment and were more likely to take daytime naps and feel that they accomplish little during the day compared to those without daytime sleepiness ( 44 ) . preliminary data suggest that poor sleep is associated with increased fatigue and daytime sleepiness , decreased quality of life , impaired self - management , increased mood disturbances , and decrements in functional outcomes in areas sensitive to sleep disruption . there is a lack of evidence regarding the potential effects of treating sleep disorders on patient - centered outcomes , suggesting that further research is necessary to evaluate whether sleep disorder treatment could be an effective strategy for addressing this potential barrier to effective diabetes management .