Abstract Body: Background:
The American Heart Association’s (AHA) Life’s Essential 8 (LE8) identifies essential metrics for cardiovascular disease prevention and includes blood glucose, blood lipids, blood pressure, nicotine exposure, physical activity, diet, sleep duration, and body mass index (BMI). While the LE8 has been linked to cardiovascular outcomes, associations with type 2 diabetes (T2D) remain less established, particularly in diverse populations.

Objective:
To examine the association between LE8 and incident T2D among postmenopausal women and to evaluate subgroups by race, ethnicity, and age.

Methods:
We included 19,403 postmenopausal women in the Women’s Health Initiative without T2D at baseline. The overall LE8 score (0–100) was calculated using AHA definitions and categorized as high (80–100), moderate (60–79), and low (0–59), with higher scores indicating a healthier lifestyle. Cox proportional hazards models estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between LE8 and incident T2D, adjusted for potential confounders.

Results:
During a mean of 16.3 years of follow-up, 3921 cases of T2D were identified. Women in the highest LE8 category had a 57% lower risk of T2D compared with those in the lowest category (HR, 0.43, 95% CI [0.38, 0.49]). A 20-point higher LE8 score was associated with a 43% lower risk (0.57 [0.54, 0.60]). Among the individual LE8 metrics, per 20-point increase in blood glucose (0.61 [0.59, 0.63]) and BMI (0.88 [0.87, 0.90]) were most strongly associated with T2D, followed by smoking (0.96 [0.94–0.98]), blood lipids (0.95 [0.93–0.97]), and blood pressure (0.95 [0.93–0.96]). Diet, physical activity, and sleep were not significantly associated with T2D in this population. Subgroup analyses showed stronger associations among Hispanic/Latina women (0.58 [0.55, 0.62]) compared with non-Hispanic women (0.46 [0.41, 0.53]), per 20-point increase. Associations were also stronger among younger women, but did not vary by race.

Conclusions:
Higher LE8 scores were associated with reduced risk of T2D in postmenopausal women, with blood glucose and BMI having the strongest associations with T2D. LE8 may serve as a practical framework for risk assessment to reduce T2D incidence in aging women.