Vitamin D status, physical activity and long-term mortality risk after myocardial infarction: a prospective analysis in the Alpha Omega Cohort.

Aim: In post-myocardial infarction (MI) patients, we examined independent and combined associations of vitamin D status and physical activity (PA) with long-term mortality, including effect modification by health determinants.

Methods: We conducted a prospective analysis of 4,837 MI patients from the Alpha Omega Cohort. Baseline blood samples (2002-2006) were assessed for plasma 25-hydroxyvitamin D (25[OH]D) levels using LC-MS/MS. PA was assessed using a validated questionnaire. Patients were followed for mortality through December 2022. HRs for CVD and all-cause mortality were obtained across sex-specific tertiles of 25(OH)D and four categories of PA using Cox models, adjusted for sociodemographic and lifestyle factors. Potential effect modification by health determinants was examined through stratification.

Results: Patients were 69±5.6 years old, 78% was male, 21% had diabetes, and 10% used vitamin D-containing supplements. Over 14.4 years, 3,206 deaths occurred, including 1,244 from CVD. Median 25(OH)D was 21.1 ng/mL and 44% was vitamin D deficient (<20 ng/mL). Higher 25(OH)D levels were associated with lower CVD (HR:0.63, 95%CI:0.54,0.74) and all-cause mortality (HR:0.68, 95%CI:0.62,0.75). For PA levels (high vs. light), HRs were 0.72 (95%CI:0.61,0.85) for CVD mortality and 0.83 (95%CI:0.75,0.92) for all-cause mortality. Patients with low 25(OH)D and no PA had a threefold higher mortality risk than those with high 25(OH)D levels and high PA. The associations were not significantly modified by sex, comorbidities and other health determinants.

Conclusions: Vitamin D status and PA were inversely and independently associated with long-term risk of CVD and all-cause mortality after MI, regardless of other health determinants.