Dyadic Associations Between Body Mass Index and the Development of Type 2 Diabetes in Romantic Couples: Results From the Health and Retirement Study

Abstract

Abstract Background Body mass index (BMI) is linked to Type 2 diabetes (T2D). Although romantic partners influence each other's health outcomes, it is unclear if partner's BMI is related to the development of T2D. Purpose To test prospective, dyadic associations between BMI and the development of T2D in middle-aged and older adult couples over 8 years. Methods Data came from 950 couples in the Health and Retirement Study. Neither partner had diabetes at baseline (2006). The actor–partner interdependence model was used to examine dyadic associations between BMI at baseline and the development of T2D during the next 8 years. Results After adjusting for covariates, a significant actor effect was observed such that one's BMI at baseline was positively associated with one's own odds of developing T2D during follow-up (odds ratio [OR] = 1.08, p < .001). A significant partner effect was also observed such that the BMI of one's partner at baseline was positively associated with one's own odds of developing T2D during follow-up above and beyond one's own baseline BMI (OR = 1.04, p = .003). These associations were not moderated by sex. This pattern of results held when BMI was coded categorically (not overweight/obese; overweight; obese). Conclusions Partner's BMI was prospectively associated with the likelihood of developing T2D. Future research should consider interpersonal risk factors for chronic health conditions, such as T2D. There is an opportunity to develop theoretical models that specify how and when partner characteristics are linked to physical morbidity.