Objective: To examine whether weight history and weight transitions over adult lifespan contribute to physical impairment among postmenopausal women.
Design: BMI categories were calculated among postmenopausal women who reported their weight and height at age 18 years. Multiple-variable logistic regression was used to determine the association between BMI at age 18 years and BMI transitions over adulthood on severe physical impairment (SPI), defined as scoring <60 on the Physical Functioning subscale of the Rand thirty-six-item Short-Form Health Survey.
Setting: Participants were part of the Women's Health Initiative Observational Study (WHI OS), where participants' health was followed over time via questionnaires and clinical assessments.
Subjects: Postmenopausal women (n 76 016; mean age 63·5 (sd 7·3) years).
Results: Women with overweight (BMI=25·0-29·9 kg/m2) or obesity (BMI≥30·0 kg/m2) at 18 years had greater odds (OR (95 % CI)) of SPI (1·51 (1·35, 1·69) and 2·14 (1·72, 2·65), respectively) than normal-weight (BMI=18·5-24·9 kg/m2) counterparts. Transitions from normal weight to overweight/obese or to underweight (BMI<18·5 kg/m2) were associated with greater odds of SPI (1·97 (1·84, 2·11) and 1·35 (1·06, 1·71), respectively) compared with weight stability. Shifting from underweight to overweight/obese also had increased odds of SPI (1·52 (1·11, 2·09)). Overweight/obese to normal BMI transitions resulted in a reduced SPI odds (0·52 (0·39, 0·71)).
Conclusions: Higher weight history and transitions into higher weight classes were associated with higher likelihood of SPI, while transitioning into lower weight classes for those with overweight/obesity was protective among postmenopausal women.
Keywords: BMI; Body weight; Disability; Physical function; Physical impairment; Weight change.