Obesity and use of acute hospital services in participants of the Renfrew/Paisley study

Background Because overweight and obesity are associated with comorbidities, increasing levels of overweight and obesity may impact on hospital use. Methods Body mass index (BMI) in middle age was related to acute hospital use in 7036 men and 8327 women from the Renfrew/Paisley prospective cohort study in Scotland. Participants in this general population study were examined between 1972 and 1976 when aged 45-64 years. Acute hospital admissions and bed days per 1000 person-years were calculated by the World Health Organization BMI categories in the follow-up period to 31 March 2004. Results Underweight and normal weight men had lower-than-expected admission rates, and overweight and obese men had higher-than-expected admission rates. Obese men had higher-than-expected bed day rates. For women, there was a U-shaped relationship with admission rate, with normal weight women having the lowest admission rate and underweight and obese women having similar high rates. Underweight and obese women had higher-than-expected bed day rates. Conclusions Participants who were obese in midlife had more-than-expected acute hospital admissions and in particular more bed days. With levels of obesity increasing since this study was started in the 1970s, if these patterns persist, there may be increasing demand on health service resources.