Long-Term Weight Trajectory and Risk of Hip Fracture, Falls, Impaired Physical Function, and Death

Abstract

Objectives: To determine the association between weight trajectory, health status, and mortality in older women.

Design: Cohort study.

Setting: Study of Osteoporotic Fractures.

Participants: Older community-dwelling women (age: baseline (1986-88), mean 68, range 65-81; Year 20 (2006-08), mean 88, range 83-102 (N = 1,323)).

Measurements: Body weight measured repeatedly over 20 years (mean 8 times). Logistic and Cox proportional hazard models were used to evaluate whether 20-year weight trajectory measures were associated with hip fracture, falls, physical performance, and mortality.

Results: In models adjusted for age, clinic, calcium use, Year 20 weight, walking speed, comorbidity score, smoking, self-reported health, and walking for exercise, women with moderate weight loss (>9.0 kg) over 20 years had a 74% greater risk of death (hazard ratio (HR) = 1.74, 95% confidence interval (CI) = 1.37-2.20) in the 5 years after the Year 20 visit than those with no weight loss and more than twice the risk of hip fracture (HR = 2.56, 95% CI = 1.39-4.70). They were 3.6 times (odds ratio (OR) = 3.60, 95% CI = 1.86-6.95) as likely to have poor physical function at the Year 20 visit as women with no weight loss but no greater risk of 2 or more falls in the 1.5 years after the Year 20 visit. Weight variability and abrupt weight decline were not associated with adverse health oucomes (falls, fractures, mortality), but those in the highest quartile of variability were 2.3 times (OR = 2.26, 95% CI = 1.34-3.80) as likely to have poor physical function scores.

Conclusion: In women surviving past 80 years of age, moderate weight loss over 20 years was associated with greater risk of hip fracture, poor physical function, and mortality but not of falls. Future work should separate voluntary from involuntary weight loss.

Keywords: fracture; mortality; physical function; weight loss.