Abstract P028: The Prognostic Utility of Vitamin D Across Continents in Patients with Suspected Acute Coronary Syndrome

Background: Several studies have demonstrated a correlation between low vitamin D levels and cardiovascular risk. Vitamin D is a fat soluble vitamin that can either be ingested (mainly from fatty fish), or created in the skin on exposure to sun. Objectives: To assess the collected prognostic utility of vitamin D measured as 25-hydroxyvitamin D [25(OH)D] in 1852 patients hospitalized with chest pain and suspected acute coronary syndrome (ACS) recruited from two continents located at opposite sides of the Equator; coastal-Norway and inland Northern-Argentina, where the vitamin D source is either a combination of diet and sun exposure or mainly sun exposure, respectively. Data from both areas were collected in a similar registry and pooled in the present analysis. Methods: 2-year follow-up data including all-cause mortality, cardiac death and sudden cardiac death (SCD) in the total- as well as in the troponin T (TnT) positive (TnT > 0.01 ng/mL) patient population were analyzed in quartiles of 25(OH)D, applying univariate and multivariable analysis. Variables included in the Cox regression model were country, TnT, hs-CRP, BNP, creatinine, age, gender, BMI, recruitment seasons and 14 other conventional risk factors for coronary heart disease. Results: At follow-up, 292 patients had died. 859 patients were TnT positive and of these 186 died. In multivariable Cox regression models for all-cause mortality, cardiac death and SCD in the total patient population, the adjusted hazard ratios (HR) for 25(OH)D in the highest quartile (Q4) as compared to the lowest quartile (Q1) were 0.52 (95% confidence interval (CI), 0.34-0.80), p=0.003, 0.54 (95% CI, 0.31-0.96), p=0.037 and 0.42 (95% CI, 0.18-0.98), p=0.045, respectively. In the TnT positive patient population the respective HRs were 0.43 (95% CI, 0.26-0.72), p=0.001, 0.47 (95% CI, 0.25-0.90), p=0.023 and 0.32 (95% CI, 0.12-0.87), p=0.025. Conclusion: Vitamin D status may serve as a prognostic indicator in chest pain patients with suspected ACS.