Major electrocardiographic abnormalities and 25-hydroxy vitamin D deficiency: insights from National Health and Nutrition Examination Survey-III.

ABSTRACT

BACKGROUND: We explored the relationship between major electrocardiogram (ECG) abnormalities (mECG) and 25-hydroxy (25-OH) vitamin D deficiency (VDD) and the effect of mECG abnormalities on all-cause and cardiovascular mortality in a healthy cohort with 25-OH vitamin D insufficiency and deficiency. HYPOTHESIS: Lower levels of serum 25-OH vitamin D are associated with increased prevalence of mECG on resting ECG. METHODS: We identified 5108 individuals from the National Health and Nutrition Examination Survey-III. mECG abnormalities included major Q-QS wave abnormalities, ST depression/elevation, negative T waves, Wolff-Parkinson-White pattern, and ventricular conduction defect. Our cohort was divided into 3 groups based on 25-OH vitamin D levels Group 1 (referent) > 40 ng/mL; group 2 (insufficient) ≥ 20.01 to ≤ 40 ng/mL; and group 3 (deficient) ≤ 20 ng/mL. Logistic regression and Cox proportional hazards regression models were built. RESULTS: The prevalence of major ECG abnormalities across 25-OH vitamin D sufficiency, insufficiency, and deficiency was .9%, 11%, and 13 %, respectively (P = 0.01). VDD was an independent predictor of mECG abnormalities after adjusting for traditional risk factors (continuous variable odds ratio [OR] 0.98, 95% confidence interval [CI] 0.97-0.99, P = 0.007; categorical variable group 3 vs group 1 OR 2.36, 95% CI 1.1-5.12, P = 0.03). Baseline major ECG abnormalities were predictive of long-term all-cause (hazard ratio [HR]1.52, 95% CI 1.23-1.89), composite cardiovascular (HR 1.7, 95% CI 1.34-2.15), cardiovascular (HR 1.64, 95% CI 1.27-2.12), and ischemic heart disease mortality (HR 1.98, 95% CI 1.46-2.69) in individuals with 25-OH vitamin D levels ≤ 40 ng/mL. CONCLUSIONS: VDD is associated with increased prevalence of major ECG abnormalities. Well-structured trials are needed to assess progression/resolution of mECG abnormalities with vitamin D supplementation in deficient individuals.