Hidden Obesity and Treatment Gaps in Japan: A Real-World Data Analysis
Author(s)
Shujiro Takeno, MBA1, Rinka Murakami, MPH2, Seok-Won Kim, PhD3, Satoshi Murayama, RPh1, Minami Yamaguchi, MSN1, Tsubasa Shimizu, MMSc1, Kaneko Shinnosuke, MSc1.
1IQVIA, Tokyo, Japan, 2IQVIA Japan, Tokyo, Japan, 3IQVIA, Minato, Japan.
1IQVIA, Tokyo, Japan, 2IQVIA Japan, Tokyo, Japan, 3IQVIA, Minato, Japan.
OBJECTIVES: To describe the prevalence, comorbidity burden, and treatment patterns of diagnosed and undiagnosed obesity in Japan, and to assess the use of GLP-1 receptor agonists (GLP-1 RAs) using real-world claims data.
METHODS: A retrospective observational study was conducted using the IQVIA Claims database in Japan, including patients with available BMI data. Obesity was defined using: (1) the Japan Society for the Study of Obesity definition (BMI ≥25 with ≥1 obesity-related comorbidity), and (2) GLP-1 RA prescription eligibility (BMI ≥35, or BMI ≥27 with ≥2 comorbidities). Patients with confirmed diagnoses but missing BMI were excluded. Demographics, comorbidity prevalence across 11 major disease categories, and GLP-1 RA prescription patterns were analyzed by age, sex, and BMI classification.
RESULTS: The prevalence of diagnosed obesity remained stable over the five-year study period. However, approximately 8% of the population met obesity Definition (2) without a formal diagnosis. Compared to non-obese individuals, this group exhibited a greater than 2% higher prevalence of depression. Among patients meeting GLP-1 RA prescription criteria, prescription rates increased over time, particularly among individuals with BMI ≥40. Despite this trend, overall treatment uptake remained low. The proportion of individuals classified as obese under Definition 2 increased with age and was consistently higher among men. In contrast, the prevalence of underweight status increased among women. Across both obesity definitions, metabolic disorders were the most frequently observed comorbidities.
CONCLUSIONS: These findings underscore the dual burden of underdiagnosed obesity and undertreatment in Japan. A substantial proportion of individuals meet clinical criteria without receiving appropriate diagnosis or intervention. Further analyses will be conducted using OMOP-standardized data to validate these findings and to reassess treatment patterns, specifically excluding newer agents such as semaglutide and tirzepatide.
METHODS: A retrospective observational study was conducted using the IQVIA Claims database in Japan, including patients with available BMI data. Obesity was defined using: (1) the Japan Society for the Study of Obesity definition (BMI ≥25 with ≥1 obesity-related comorbidity), and (2) GLP-1 RA prescription eligibility (BMI ≥35, or BMI ≥27 with ≥2 comorbidities). Patients with confirmed diagnoses but missing BMI were excluded. Demographics, comorbidity prevalence across 11 major disease categories, and GLP-1 RA prescription patterns were analyzed by age, sex, and BMI classification.
RESULTS: The prevalence of diagnosed obesity remained stable over the five-year study period. However, approximately 8% of the population met obesity Definition (2) without a formal diagnosis. Compared to non-obese individuals, this group exhibited a greater than 2% higher prevalence of depression. Among patients meeting GLP-1 RA prescription criteria, prescription rates increased over time, particularly among individuals with BMI ≥40. Despite this trend, overall treatment uptake remained low. The proportion of individuals classified as obese under Definition 2 increased with age and was consistently higher among men. In contrast, the prevalence of underweight status increased among women. Across both obesity definitions, metabolic disorders were the most frequently observed comorbidities.
CONCLUSIONS: These findings underscore the dual burden of underdiagnosed obesity and undertreatment in Japan. A substantial proportion of individuals meet clinical criteria without receiving appropriate diagnosis or intervention. Further analyses will be conducted using OMOP-standardized data to validate these findings and to reassess treatment patterns, specifically excluding newer agents such as semaglutide and tirzepatide.
Conference/Value in Health Info
2025-11, ISPOR Europe 2025, Glasgow, Scotland
Value in Health, Volume 28, Issue S2
Code
RWD97
Topic
Epidemiology & Public Health, Patient-Centered Research, Real World Data & Information Systems
Topic Subcategory
Health & Insurance Records Systems, Reproducibility & Replicability
Disease
Cardiovascular Disorders (including MI, Stroke, Circulatory), Diabetes/Endocrine/Metabolic Disorders (including obesity), Mental Health (including addition)