Vitamin D deficiency in postmenopausal, healthy women predicts increased cardiovascular events: a 16-year follow-up study

Objective: To investigate the relationship between vitamin D status in healthy women and cardiovascular outcome. Design and methods: Between 1990 and 1993, 2016 healthy, recently postmenopausal women were enrolled in the Danish Osteoporosis Prevention Study. Serum levels of 25-hydroxyvitamin D (25(OH) D, nmol/l) were measured at baseline. Participants were followed for 16 years. The primary end point was a combinationof death, heart failure, myocardial infarction (MI) and stroke. Vitamin D deficiency was defined as serum 25(OH)D < 50 nmol/l. The primary end point was adjusted for other risk factors of adverse cardiovascular events (age, smoking, blood pressure, hip-waist ratio, education and family history of MI). Results: At baseline, mean age was 50 years and BMI 25. Women with vitamin D deficiency (n = 788) had more cardiovascular risk factors than vitamin D-replete women (n = 1225). Compared with vitamin D-replete women, women with low 25(OH)D levels had significantly higher BMI and triglycerides, lower HDL andhip-waist ratioand less education. Morewere smokersamong the vitamin D deficient (47vs38%). A primary end point was experienced by 118 (15%) with vitamin D deficiency and by 125 (10%) of the vitamin D replete. Hazard ratio (HR) was 1.49 (95% confidence interval: 1.16-1.92; P = 0.002) in the vitamin D deficient. Adjusted HR was 1.32 (1.02-1.71; P = 0.03). In total, 135 women died; of these, 65 (8%) were of the vitamin D deficient and 70 (6%) in the vitamin D-replete group; unadjusted HRwas 1.44 (1.02-2.01; P = 0.04) for vitamin D deficiency. Conclusion: Healthy women with vitamin D deficiency have increased risk of adverse cardiovascular outcome.