Aims: The aim of this study was to investigate the relation between body mass index (BMI) in young women, using weight early in pregnancy as a proxy for pre-pregnancy weight, and risk for early cardiovascular disease (CVD) and mortality.
Methods and results: In this prospective, registry-based study, we used weight data in early pregnancy from women, registered in the Swedish Medical Birth Registry, and who gave birth between 1982 and 2014 (n = 1,495,499; median age 28.3 years). Of the women, 118,212 (7.9%) were obese (BMI ≥ 30 kg/m2) and 29,630 (2.0%) severely obese (BMI ≥ 35 kg/m2). After a follow-up of median 16.3 years, we identified 3295 and 4375 cases of acute myocardial infarction (AMI) and ischemic stroke (IS) corresponding to 13.4 and 17.8 per 100,000 observation years, respectively, occurring at mean ages of 49.8 and 47.3 years. Compared to women with a BMI 20-<22.5 kg/m2, the hazard ratio (HR) of AMI increased with higher BMI from 1.40 (95% confidence interval (CI) 1.27-1.54) among women with BMI 22.5-<25.0 kg/m2 to 4.71 (95% CI 3.88-5.72) among women with severe obesity, with similar findings for IS and CVD death, after adjustment for age, pregnancy year, parity and comorbidities at baseline. Women with BMI 30-<35.0 and ≥35 kg/m2 had increased all-cause mortality with adjusted HR 1.53 (95% CI 1.43-1.63) and 1.83 (95% CI 1.63-2.05), respectively.
Conclusion: A significant increase in the risk for early AMI, IS and CVD death was noticeable in overweight young women, with a marked increase in obese women.
Keywords: Overweight; cardiovascular disease; epidemiology; mortality; obesity.
© The Author(s) 2020. Published by Oxford University Press on behalf of the European Society of Cardiology.