Enormous evidence suggests that vitamin D deficiency could be linked to several chronic diseases, including cardiovascular disease, diabetes, obesity, depression and cancer. The purpose of this study was to examine the prevalence of vitamin D deficiency and its correlates to test the hypothesis that vitamin D deficiency was common among adult Turkish population, particularly in women. The Turkish Diabetes, Hypertension, Obesity and Endocrine Disease Survey (TURDEP-II) Jan to June 2010 data were analyzed for vitamin D levels in adult participants (n=9560, mean (S.D.) age: 45.3 (15.4) years, 64% women).
Serum 25(OH)D was inversely correlated with PTH (r=−0.122, P<0.001). Serum 25(OH)D levels (controlled for age, gender, region, living environment, BMI, waist, and season) correlated with fish, cheese, and sunflower oil consumption; serum levels of creatinine, LDL-cholesterol, HDL-cholesterol, FT4, vitamin B12, folates, IGF1, IGFBP3 and eGFR.
Vitamin D deficiency was defined as 25(OH)D concentrations ≤20 ng/ml (≤50 nmol/l). The overall prevalence rate of vitamin D deficiency was 93%, with the highest rate seen in younger (<40 years) age group (96.2%) in women, and elderly (≥65 years) age group (91.9%) in men.
Multiple logistic regression model with Z scores showed that male gender, increase in total cholesterol (39.3 mg/dl), HDL-cholesterol (12.3 mg/dl) and IGF1 levels (69.0 ng/ml) positively associated; but eGFR (18.6 ml/min) and PTH (22.7 pg/ml) levels inversely associated with vitamin D (≥20 ng/ml).
In conclusion, vitamin D deficiency was common among adult Turkish population, particularly in child-bearing age women. Given that vitamin D deficiency is linked to important risk factors of leading cause of morbidity and mortality in Turkey, it is important that health professionals should be aware of this connection and health authorities arrange intervention strategies, such as vitamin D fortification of foods to correct vitamin D deficiency at the population level.