U-shaped association of body mass index in early adulthood with unintentional mortality from injuries: a cohort study of Swedish XXXX with 35 years of follow-up.

@entity1 @entity204 @entity28 @entity18469
OBJECTIVES: To investigate the dose-response association between body mass index (BMI) in young adulthood and the risk of mortality caused by unintentional injuries. METHODS: We performed a cohort study including 7   43   398 @entity1 identified by linkage of the Multigeneration Register and the Military Service Conscription Register. Cox regression models were used to examine crude and adjusted hazard ratios (HRs) and 95% confidence intervals (95% CIs) of the relationships between BMI at age 18-20 years and the risk of @entity204 from all unintentional injuries as well as from specific unintentional injuries. We then estimated the population attributable fractions (PAFs)-the proportion of unintentional @entity204 that was attributable to underweight, overweight and @entity28 in this population-based cohort. RESULTS: During 35.9 years of follow-up, 6461 @entity204 occurred from unintentional injuries, including 3064 @entity204 from road injury, 978 from poisoning, 503 from falls, 243 from fire and 348 from drowning. Underweight subjects had a higher risk of mortality in all unintentional injuries (HR, 1.05; 95% CI, 1.03-1.10) and mortality in burns (HR, 1.65; 95% CI, 1.13-2.40) compared with BMI between 18.5 and 22.5   kg   m(-2) (reference group). BMI >25   kg   m(-2) was associated with increased risk of @entity204 from all unintentional injuries (HR, 1.36; 95% CI, 1.12-1.65) and road accidents (HR, 1.50; 95% CI, 1.14-1.97). Estimates of @entity18469 suggested that 4.4% of the mortality in Swedish @entity1 caused by unintentional injuries could have been avoided if BMI values were kept between 18.5 and 22.5   kg   m(-2). CONCLUSIONS: A U-shaped association was observed between BMI and risk of unintentional @entity204 . Both underweight and overweight were associated with increased mortality risk for all unintentional injuries and for subtype causes. Our study suggests that BMI might be a significant target for preventive interventions on @entity204 caused by unintentional injuries.
