Exploring the Burden of Knee Osteoarthritis in Rural South India: Community Prevalence, Risk Factors, and Functional Assessment Among Adults Aged 40 and Above.

Background The rising prevalence of osteoarthritis (OA) will create significant challenges for low-resource public health systems in countries like India, leading to increased disability and reduced quality of life. Limited access to imaging and specialized orthopedic care in rural areas often delays diagnosis and treatment until the disease has progressed to advanced stages, further burdening the economy. Objectives To estimate the community prevalence and assess the risk factors associated with OA among adults aged 40 and older in rural areas of South India and to determine their functional assessment among OA-diagnosed patients. Methods A community-based cross-sectional study was conducted in rural Tiruvallur district, Tamil Nadu, South India, from September 2017 to August 2018 among 427 people aged 40 and above. People with rheumatoid arthritis, reactive arthritis, old trauma of knee joint, and who have undergone total knee replacement were excluded from the study. A validated semi-structured questionnaire was used which consisted of the socio-demographic profile of the individuals, risk factors of knee OA, American College of Rheumatology (ACR) criteria for diagnosis of knee OA, Western Ontario and McMaster Universities Arthritis Index (WOMAC) scale and Visual Analog Scale (VAS) for functional assessment. A chi-square test and odds ratio were used to determine the significant risk factors and multivariate binomial logistic regression was performed to identify the predictors of knee OA. Results The mean age of the study population was 60 years ranging from 42 to 89 years with 48% males and 52% females. The community prevalence of knee OA was 34.6%. The significant predictors for the development of OA were diabetes, obesity, Indian toilet use, and hypertension in women. The level of pain among OA patients was higher for standing from a sitting position and while climbing upstairs. The mean WOMAC score of OA subjects was 57.38 (± 12.16) ranging from 25 to 78.  Conclusion The study reveals a high prevalence of knee OA among over one-third of individuals aged 40 and above in rural South India, with significant risk factors including obesity, diabetes, hypertension, menopause, sedentary lifestyles, and Indian-style toilets. Severe functional impairment, indicated by high WOMAC scores, underscores limited healthcare access, emphasizing the need for community interventions in lifestyle modification and chronic disease management.