Long-term impact of weight loss in people with class II obesity on the overall burden of disease: evidence from the national health screening cohort in Korea.

BACKGROUND:Obesity is known to increase overall disease burden but does obesity management actually help reduce disease burden? OBJECTIVES:To investigate the effects of weight loss on disease burden in people with obesity using the National Health Insurance Service-Health Screening Cohort (NHIS-HEALS) in Korea. SETTING:Pure longitudinal observational study using Nationwide cohort database. METHODS:Out of 514,866 NHIS-HEALS cohort, participants with class II obesity in Asia-Pacific region (30 ≤ body mass index [BMI] < 35) who underwent health check-up provided by NHIS during 2003-2004 (index date) were included. All final participants continued to receive a total of 5 biennial health check-ups over the next 10 years without missing. A group-based trajectory model (GBTM) was used to categorize subjects based on 10-year BMI change patterns. The changes of co-morbidities, healthcare resource utilization, and medical cost were analyzed. RESULTS:The final study subjects (9857) were categorized into 3 trajectory clusters based on the pattern of BMI (kg/m2) change: maintenance (57.35%) with an average change of -.02 ± .06, loss (38.65%) with -.04 ± .08, and substantial loss (4.0%) with -.10 ± .18. The annual increases in the number of co-morbidities per subject in each cluster were .18, .18, and .16 (all P < .001), respectively. The increase of healthcare resource utilization over time was lowest for the substantial loss compared to maintenance and loss. With each passing year, the average annual total healthcare cost increased by ₩21,200 ($16.48, P = .034) and ₩10,500 ($8.16, P = .498) in the maintenance and loss, respectively, but decreased by ₩62,500 ($48.59, P = .032) in the substantial loss. CONCLUSIONS:Weight loss in people with obesity was associated with a reduced burden of disease, as evidenced by lower co-morbidity, healthcare resource utilization rate, and decreased medical costs. This study highlights the potential positive long-term impact on Korean society when actively managing weight in individuals with obesity.