Predictive Factors for Knee Osteoarthritis Severity among Older Adults in Pong District, Phayao Province, Rural Northern Thailand: A Cross-Sectional Study

Background: Knee osteoarthritis (KOA) causes joint pain and reduced mobility in older adults. This study examined factors predicting KOA severity among elderly individuals in rural Pong District, Phayao Province. Methods: A cross-sectional study using multistage random sampling was conducted on 384 individuals aged 60 and older residing in the Na Prang Subdistrict between July and September 2024. Clusters were formed based on social groups, followed by simple random sampling within clusters. Data were collected through questionnaires assessing demographics, health literacy, preventive behavior, and KOA severity using the Oxford Knee Score. Data analysis involved descriptive statistics, Pearson's correlation, and multiple linear regression. Results: The study indicated that most participants were female (59.4%), aged 60–69 years (66.1%, Mean = 68.18, SD = 6.45, Min = 60, Max = 91), with income of no more than 5,000 baht (90.4%), were married (73.4%), and had some level of education (91.5%). A majority (61.5%) suffered from severe knee osteoarthritis. Multiple regression analysis identified 4 key predictors of knee osteoarthritis severity: age (β=0.100, P< 0.05), osteoarthritis knowledge (β = 0.131, P< 0.05), preventive behaviors (β = -0.189, P< 0.001), and daily activity ability (β= -0.330, P< 0.001), explaining 17.4% of the variance (adjusted R² = 0.174, F = 60.839, p < 0.001). Conclusion: Enhancing health knowledge, preventive behaviors, and tailored rehabilitation can help older adults manage osteoarthritis and reduce severity through improved functionality, lifestyle, and older adult education.