Population Aging, Obesity, and Regional Disparities in Osteoarthritis Prevalence Across World Health Organization Regions: A Panel Data Study

Abstract

Objective: Although previous studies have examined the relationship between osteoarthritis (OA), aging, and obesity in selected settings, evidence at the level of World Health Organization (WHO) regions remains limited. The aim was to assess regional disparities and temporal trends in OA prevalence across WHO regions and its association with population aging and obesity.

Methods: This longitudinal ecological panel study included 6 WHO regions from 2000 to 2016, with region-year as the unit of analysis (102 observations). Osteoarthritis prevalence data were obtained from the Global Health Data Exchange, population aging data from the World Bank Database, and obesity prevalence data from Our World in Data. Descriptive statistics and graphical-trend analysis were performed. Panel regression models were fitted, and fixed effects with Driscoll–Kraay robust standard errors were used after testing for unit and time effects, heteroskedasticity, autocorrelation, and cross-sectional dependence.

Results: Osteoarthritis prevalence showed substantial regional and temporal variation. The most evident declines were observed in the African, Eastern Mediterranean, and South-East Asian regions, whereas population aging and obesity increased across all regions, particularly in Europe and the Americas. In the adjusted panel model, population aging was positively associated with OA prevalence (β = 26.65, standard error (SE) = 5.65, P < .001), while obesity prevalence was negatively associated with OA prevalence (β = −5.38, SE = 1.74, P = .002).

Conclusion: Osteoarthritis prevalence across WHO regions is shaped by demographic aging and marked regional heterogeneity. The inverse association observed for obesity should be interpreted cautiously given the ecological design and potential residual confounding. These findings support region-sensitive approaches to OA surveillance, prevention, and health-system planning, particularly in the context of population aging and its likely economic implications.

Cite this article as: Afacan MY, .zer M, Celayir A, et al Population aging, obesity, and regional disparities in osteoarthritis prevalence across World Health Organization regions: A panel data study. Cerrahpaşa Med J 2026, 50, 0052, doi: 10.5152/cjm.2026.26052.