Longitudinal Medical Costs and Hospitalization Risk Associated With Sustained Obesity

PurposeTo assess the association of sustained obesity with medical expenditures and risk of hospitalization over time.DesignRetrospective cohort study.SettingThis study used linked data from ambulatory electronic medical records and medical claims.SampleAdults aged 17-64 years with (1) continuous enrollment in an insurance plan and (2) weight measured each year over ≥5 calendar years during 2013-2020.MeasuresOutcome variables were annual medical expenditures and annual risk of hospitalization. Covariates included sustained obesity or sustained severe obesity (reference: sustained healthy weight), year, age, sex, race, and US Census region.AnalysisGeneralized estimating equations were used to assess how excess costs and risk of hospitalization increased with sustained obesity or severe obesity over 8 years.ResultsObesity-associated excess expenditures grew from $1105 or 20% in year 1 to $5229 or 49% in year 8. The relative risk of hospitalization grew from 13% in year 1 to 159% in year 8 among persons with sustained obesity (versus those with sustained healthy weight). Differences were higher for those with severe obesity, and higher among females (compared to males) and those aged 40-64 years (compared to those aged 17-39 years).ConclusionsThis study's findings provide evidence of a compounding effect of sustained obesity on medical expenditures and hospitalization risk over time. These findings underscore the importance of efforts that promote and support healthy lifestyles, including community access to healthy foods and physical activity for all.