We 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.
A 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.
Serum 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