Abstract
BACKGROUND: Women with a history of gestational diabetes (GDM) have an increased risk of cardiovascular disease (CVD) throughout their lifetime. It is still unclear whether adhering to a healthy lifestyle can modify the association of GDM with the risk of CVD and mortality. METHODS: This study included 125,435 parous women from the UK Biobank prospective cohort. The history of GDM was determined by self-reported diagnosis or hospital admission records. A healthy lifestyle score was defined by incorporating self-reported information on five modifiable risk factors, including smoking, alcohol intake, physical activity, diet, and sleep duration. The primary outcome was a composite of major CVD and all-cause mortality. RESULTS: The mean age was 56.4 ± 7.9 yrs, and 668 participants had a history of GDM. After a median follow-up of 13.6 years, 9371 had major CVD events, and 6750 died. The association between GDM history with the composite of major CVD and all-cause mortality was stronger among women with the least healthy lifestyles (HR, 2.35 [95% CI, 1.72-3.22]) compared to those with moderately healthy (1.31 [0.84-2.06]) or the healthiest lifestyles (1.24 [0.75-2.06]; P = 0.001 for interaction). The relative excess risk due to interaction between GDM history and the least healthy lifestyles was 0.52 (0.27-0.77; P = 0.02). Compared to women with no GDM history and the healthiest lifestyle, those with GDM history and the least healthy lifestyle had a threefold increased risk of the composite outcome (3.00 [2.20-4.10]), while women with GDM history and the healthiest lifestyle did not experience a significantly higher risk (1.19 [0.71-1.97]). CONCLUSIONS: Women with a history of GDM did not experience a higher risk of all-cause mortality and major CVD when adhering to a healthy lifestyle in midlife.