Serum 25-hydroxyvitamin D concentration, established and emerging cardiovascular risk factors and risk of myocardial infarction before the age of 60 years

Abstract

ObjectiveWe examined the relationships of serum 25-hydroxyvitamin D (25(OH)D) concentration to established and emerging cardiovascular risk factors and risk of myocardial infarction (MI) in a population-based case–control study of MI before the age of 60 years. MethodsA total of 387 survivors of a first MI and 387 sex- and age-matched controls were included. Fasting blood samples drawn three months after the MI in cases and at the same time in the matched controls were used for biochemical analyses. ResultsSerum concentrations of 25(OH)D, adjusted for seasonal variation, were lower in cases than controls (55.0 (40.0–71.0) nmol/L vs 60.5 (47.0–75.0) nmol/L; median (interquartile range); standardized odds ratio (OR) for MI with 95% confidence interval in univariable analysis: 0.80 (0.69–0.93); p = 0.003). The 25(OH)D association with MI disappeared after adjustment for established and emerging risk factors (OR: 1.01 (0.82–1.25)). Current smoking and plasma levels of proinsulin and PAI-1 activity were independently associated with 25(OH)D in controls, whereas waist circumference, plasma triglycerides, proinsulin, PAI-1 activity and cystatin C, and non-Nordic ethnicity were independently associated with 25(OH)D in patients. Serial measurements of 25(OH)D (samples drawn <4 h and 3 months after the onset of MI) in 57 patients showed no systematic differences between sampling times. ConclusionVitamin D insufficiency, which is associated with a multitude of metabolic, procoagulant and inflammatory perturbations, is not independently related to premature MI. This suggests that vitamin D insufficiency either constitutes an epiphenomenon or increases the risk of MI by promoting established risk factor mechanisms that predispose to atherothrombosis.