Low Vitamin D and Cardiovascular Risk Factors in Males and Females from a Sunny, Rich Country

BACKGROUND: Low serum vitamin (vit) D levels are common even in sunny countries. We assessed the prevalence and relationship of low vit D with cardiovascular risk factors in Qatar. METHODS: Data were collected retrospectively from January 2008 and November 2009. In patients who had low vi t D (< 30 ng/ml ) , demographic and clinical profiles were analyzed and compared in males and females. RESULTS: The overall mean level of vit D among 547 patients was 14.4±11 ng/mL. Among the low vitamin D group, 56% were females (mean age 48±12) and 44% males (mean age 49.6±13). Severely low vit D levels (<10 ng/mL) were found in 231 (46%) patients with mean age of 46±12 years. Compared with females, males with low vitamin D were more likely to have diabetes mellitus (38 vs 22%, p=0.001), dyslipidemia (41 vs 29%, p=0.007), myocardial infarction (5.5 vs 1.5%, p=0.001) and angiographically documented coronary artery disease (CAD) (53 vs 17%, p=0.001). Multivariate logistic regression analysis showed that in the presence of low vit D, age and hypertension were independent predictors of CAD (OR 1.07;95% CI: 1.02-1.11) and OR 8.0; 95% CI: 1.67-39.82), respectively. CONCLUSIONS: Our study supports the widespread prevalence of low vit D in sunny regions. Low vit D is associated with 3 times increase in the rate of MI among males. Hypertension increases the risk of CAD 8 times in the presence of low vit D regardless of gender.