Real-World Weight Loss Outcomes by Obesity Management Approaches in Japan: Descriptive Findings from the J-ORBIT Database Linked to Electronic Medical Records (J-ORBIT2)

The current clinical reality and burden of obesity disease in Japan are poorly understood. To address this knowledge gap, in this real-world study we describe the characteristics of Japanese individuals with obesity disease (IwOD) and their obesity disease treatments using data from the Japan Obesity Research Based on electronIc healTh record (J-ORBIT) database. This retrospective observational study (January 2019 to January 2024) assessed data of ≥ 18-year-old IwOD registered in J-ORBIT and diagnosed with primary obesity per the criteria of the Japan Society for the Study of Obesity (JASSO). IwOD were grouped according to the most advanced treatment received during the study period, including the index date: lifestyle intervention, pharmacotherapy, or bariatric surgery. Demographic and clinical characteristics, degree of weight reduction, and percent change in metabolic parameters from baseline to the latest follow-up timepoint were described. Among the 782 IwOD included in this study, 274, 487, and 21 had received advanced treatment in the form of lifestyle intervention, pharmacotherapy, and bariatric surgery, respectively. At baseline, across treatment groups the mean age ranged from 45 to 57 years, female proportion ranged from 45% to 76%, and body mass index (BMI) ranged from 31 to 39 kg/m 2 , respectively. Across treatment groups, 62–69% had ≥ 3 obesity-related health disorders (ORHDs) at baseline. Mean follow-up periods in these groups ranged from 846 to 1211 days. Mean weight and BMI numerically decreased from baseline to follow-up across groups. In the lifestyle intervention , pharmacotherapy, and bariatric surgery groups, 38%, 45%, and 65% of IwOD achieved ≥ 3% weight reduction at the latest follow-up timepoint. IwOD with baseline BMI ≥ 30 kg/ m 2 tended to achieve greater weight reduction. Triglyceride, high-density lipoprotein-cholesterol, blood glucose, hemoglobin A1c, and uric acid levels tended to improve in IwOD with ≥ 3% weight reduction and greater categories. Obesity-associated burden in terms of ORHDs was common among Japanese IwOD. Although IwOD tended to have the highest weight reduction after bariatric surgery, this treatment is indicated for a highly restrictive population and requires specific criteria to be met, leaving many IwOD with unmet needs. These IwOD may need pharmacotherapy for better weight management than that provided by current options.