Association Between Self-Reported Sleep Duration and Serum Vitamin D Level in Elderly Korean Adults

• Published in: Journal of the American Geriatrics Society (JAGS) 2014-12, Vol.62 (12), p.2327-2332
• Main Authors: Kim, Jeong Hong, Chang, Jung Hyun, Kim, Dong Young, Kang, Ju Wan
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Biological and medical sciences; Confounding Factors (Epidemiology); Cross-Sectional Studies; elderly; Female; General aspects; Geriatrics; Humans; Interviews as Topic; Male; Medical sciences; Middle Aged; Miscellaneous; Older people; Public health. Hygiene; Public health. Hygiene-occupational medicine; Republic of Korea - epidemiology; Risk Factors; Sleep; sleep duration; Sleep Wake Disorders - blood; Sleep Wake Disorders - epidemiology; Surveys and Questionnaires; Vitamin D; Vitamin D Deficiency - blood; Vitamin D Deficiency - epidemiology
• ISSN: 0002-8614; 1532-5415
• DOI: 10.1111/jgs.13148

Objectives To investigate the association between self‐reported sleep duration and serum vitamin D level in elderly Korean adults. Design Cross‐sectional data analysis. Setting Korean National Health and Nutrition Examination Survey 2010. Participants Noninstitutionalized adults aged 60 to 80 (N = 1,614). Measurements The confounding variables were serum 25‐hydroxy vitamin D level, age, sex, body mass index, smoking history, alcohol consumption, and self‐reported daily sun exposure and sleep duration. Self‐reported daily sleep duration was divided into four groups: Q1 (≤4 hours), Q2 (5–6 hours), Q3 (7–8 hours), and Q4 (≥9 hours). Results Mean serum vitamin D levels of subjects in the Q1, Q2, Q3, and Q4 groups were 44.18, 48.08, 48.83, and 51.78 nmol/L, respectively. On multivariate linear regression analysis, subjects in the Q2 (B = 3.80, 95% confidence interval (CI) = 0.42–7.19), Q3 (B = 4.89, 95% CI = 1.54–8.24), and Q4 (B = 5.18, 95% CI = 0.78–9.58) groups had significantly higher serum vitamin D levels than subjects in the Q1 group. Conclusion Serum vitamin D level is positively associated with self‐reported daily sleep duration in elderly Korean individuals. These results suggest that inadequate sleep duration may be associated with lower vitamin D levels in elderly adults.