The effects of obesity, smoking, and excessive alcohol intake on healthcare expenditure in a comprehensive medical scheme.

BACKGROUND Health risks such as tobacco use, excessive alcohol consumption and unhealthy body weight contribute to the development of chronic health problems. OBJECTIVE To estimate the associations of tobacco use, excessive alcohol consumption and obesity with healthcare expenditure and chronic diseases among South Africans on a comprehensive medical scheme. METHODS We performed a cross-sectional analysis of health survey and medical claims data for 70 000 South Africans during 2010. RESULTS Moderately obese individuals, with a body mass index (BMI) of 30 - 35 kg/m2 averaged R2 300 (11%) higher annual medical expenditure in the year 2010 than never-smokers with a BMI <30 kg/m2. This increase is comparable with being a current or past smoker (expenditure increase by R2 600; 13%). Severely obese individuals (BMI >35 kg/m2), however, had increased healthcare costs of R4 400 (23% increase). This exceeds the difference between a 40- and a 50-year-old (increase of R3 200). Being overweight or excessive consumption of alcohol was not significantly associated with medical expenditures. Absolute and relative excess expenditures associated with these health risks are higher among older individuals. In the 54 - 69-year age group, estimated additional expenses were R6 200 for smoking (20% increase over never-smokers with BMI <30 kg/m2), R6 600 for moderate obesity (21%) and R15 800 for severe obesity (51% increase). Overweight or heavy drinking was not statistically significantly associated with healthcare expenditure. CONCLUSION Obesity and tobacco use are associated with significantly increased healthcare expenditure. Severe obesity doubles these excess costs.