The relationship of body mass index and functional outcomes in patients with acute burns.

Obesity may contribute to the functional decline in elderly adults. It can also increase the risk of mortality in burn patients. However, little data exist regarding the relationship between obesity and functional outcomes in patients with burns. Data were collected regarding admission body mass index (BMI), length of stay, TBSA burn, inhalation injury, age, sex, discharge disposition, and discharge functional independence measure (FIM) scores for 221 patients. We used the classification and regression trees (CART) method to determine the strongest predictors of discharge disposition and FIM scores. Patients older than 59, with 0 to 30.75% TBSA burn, and a BMI of less than 27 were more likely to return home when compared with matched patients with a greater BMI. Regardless of age and BMI, patients with greater than 30.75% TBSA burn were less likely to return home (27.6%) posthospitalization when compared with patients with less than 30.75% TBSA burn (82.8%). Patients aged 54 to 72 years with less than 22.50% TBSA burn and a higher BMI (>25.15) demonstrated lower FIM locomotion scores than corresponding patients with a lower BMI (<25.15). Older patients (>72.5 years) with burns less than 22.50% TBSA and a larger BMI (>31.25) had lower transfer FIM scores when compared with matched patients with a smaller BMI (< or =31.25). Among patients with greater than 22.50 TBSA burn, women demonstrated lower FIM transfer and locomotion scores when compared with men. BMI may contribute to lower functional scores and the likelihood of discharge to an inpatient setting in elderly patients with less severe burns.