Association between obesity and injury among Taiwanese adults

Background: The prevalence of obesity and injury has increased in Asian countries, but the relationship between obesity and injury is less well established. The aim of this study is to evaluate the relationship between body mass index (BMI), the occurrence of injury, and the injury-related expenditure among Taiwanese adults. Design: Retrospective cohort study. Methods: Our study sample consisted of 12 520 adults aged 18 years or older from the 2001 National Health Interview Survey, who had consented to the linking of their survey responses with their National Health Insurance claims records. Cox proportional hazards regression and a two-part model were used for analysis. Results: The results show that there was a positive association between BMI and injury. Relative to normal-weight adults, the hazard ratio (HR) of injury were 1.21 (95% confidence interval (CI): 1.08-1.36) for obese class II adults and 1.11 (95% CI: 1.05-1.18) for obese class I adults, after adjusting for confounding factors. The HR of sustained strain/sprain rose to statistical significance (P<0.001) among persons with a higher BMI. For obese class II and I adults, the adjusted injury-related expenditure levels were 33.4 and 15.6%, respectively, greater than those of normal-weight adults. Conclusions: There was a strong positive relationship between high BMI and increased risk of injury as well as higher injury-related expenditure. Specifically, a high BMI was associated with an increased risk of strain/sprain. Low-intensity flexibility, strength, and balance training programs should be considered in addition to weight reduction programs to prevent strain/sprain for obese adults.