Predictors of vitamin D deficiency and insufficiency in adult Bahrainis: a cross-sectional study

OBJECTIVE: High prevalence of hypovitaminosis D has been reported to be common in different regions of the Middle East. The objective of the present study was to examine the predictors of vitamin D deficiency and insufficiency in Bahrainis. DESIGN: A cross-sectional study. SETTING: Blood transfusion volunteers at a blood bank. SUBJECTS: Serum levels of total 25-hydroxyvitamin D, bone markers and other parameters such age, sex, season and clothing style in the 500 healthy Bahrainis were investigated. RESULTS: In the entire cohort the prevalence of vitamin D deficiency was 49.4% and the relative risk of vitamin D deficiency increased significantly by 1.1, 1.2, 1.5, 1.7 and 1.2 fold with younger age group (P = 0.03), hyperparathyroidism (P = 0.01), low serum Ca (P < 0.001), warm and hot months of the year (P < 0.0001) and female sex (P = 0.002), respectively. In females the prevalence of vitamin D deficiency was 67.6% and the relative risk of vitamin D deficiency increased significantly by 1.1, 1.2, 1.2, 1.2 and 1.4 fold with younger age group (P = 0.04), hyperparathyroidism (P = 0.03), low serum Ca (P = 0.001), warm and hot months of the year (P = 0.001) and conservative clothing style (P = 0.04), respectively. In contrast, in males the prevalence of vitamin D deficiency was 31.2% and the relative risk of vitamin D deficiency was increased by 1.6 fold in warm and hot months of the year (P < 0.0001). CONCLUSIONS: High prevalence of low circulating levels of vitamin D and the relative risk factors associated with vitamin D deficiency and insufficiency observed in the present study suggest an urgent need for public health interventions including vitamin D food fortification in Bahrain.