The impact of body mass index on severity, patterns and outcomes after traumatic brain injuries caused by low level falls.

Abstract

Low level falls are a common cause of traumatic brain injuries (TBI) and are associated with significant mortality and disability. The aim of this study was to analyse whether BMI, height and weight of patients were related to severity, patterns and outcomes of TBI caused by low level falls. Data on patients with TBI where cause of injury was a low level fall (fall < 3 m) with known body mass index (BMI) (N = 683) were analysed. Patients were categorized into underweight, normal, pre-obese and obese based on BMI and demographic characteristics, injury severity, patterns and outcomes were compared. In addition, physiological status, comorbidities and length of hospitalization were analysed in a subset of patients where this information was available. The median BMI was 25.6. About 1/10 of patients were obese. The mean age and proportion of male sex of patients was increasing with increasing BMI. The patients in all BMI groups were of similar injury severity and neurological status. There was also no difference in mortality and functional outcome based on patient's BMI. Obese and pre-obese patients required longer stay at ICU and in hospital. We found no associations between BMI and severity or outcome of TBI caused by low level falls. More detailed data and further studies are needed to fully elucidate these complex relationships.