Vitamin D levels in primary care patients: correlations with clinical, seasonal, and quality-of-life parameters

The prevalence of vitamin D deficiency varies across countries and few data exist in the adult population in Greece. To assess vitamin D levels in unselected patients from primary care and to investigate possible correlations with clinical, seasonal, and quality-of-life parameters. In this cross-sectional study, 389 consecutive patients were included. They were grouped according to vitamin D status as vitamin D deficient (10; OR = 3.769, 95% CI = 0.984-14.443, P = 0.04), and fatigue (FSS >36; OR = 7.157, 95% CI = 0.855-59.877, P = 0.04) showed significant independent associations with vitamin D deficiency in specific subgroups of patients. A large proportion of patients in primary care had vitamin D deficiency, independently associated with hypertension, sleepiness, depressive symptoms, and fatigue. Further research is needed in order to determine the role of vitamin D in these patients.