Low serum vitamin D among community-dwelling healthy women in Sri Lanka

Background: Although hypovitaminosis D is prevalent among healthy adults in Asia and other regions, available data among Sri Lankans are not consistent with this finding. We studied vitamin D level among healthy community-dwelling women and examined its effects on parathyroid hormone (PTH) level and bone mineral status. Methods: Females of 20 40 years (n = 434) who were employed in southern Sri Lanka were recruited to the study. Bone mineral density and content (pBMD and pBMC) of the middle phalanx of the middle finger of the non-dominant hand were measured in all subjects and 5.0 ml of venous blood was collected from each subject after an overnight fast for biochemical assessment of serum vitamin D, parathyroid hormone and total alkaline phosphatase. Results: Mean (SD) pBMD of the women studied was 0.493 (0.060) g/cm and pBMC was 1.49 (0.28) g. Severe vitamin D deficiency (<12.5 nmol/L) was seen in 21.4% of subjects, whereas 19.1% subjects had moderate (12.5 25.0 nmol/L) and 15.7% had mild (25.1 35.0 nmol/L) vitamin D deficiency. Serum vitamin D showed significant positive correlations with pBMD (r = 0.13, p = 0.008) and pBMC (r = 0.12, p = 0.01). In regression analysis, vitamin D showed a positive association with pBMD (regression coefficient 0.0003, SEM 0.0001, p = 0.007). Conclusions: Vitamin D insufficiency/deficiency is prevalent among healthy young and middle-aged women in this study group selected from southern Sri Lanka. The accompanying rise of PTH indicates the biological significance of low vitamin D level. The negative effects observed on bone mineral status suggest the clinical importance of this finding.