Analysis of Social Aspects Associated with Osteoarthritis in the Brazilian Population: A Cross-sectional Study Based on the National Health Survey in Brazil (PNS 2013)

Background: Osteoarthritis (OA) is considered the third most prevalent chronic non-communicable disease in the Brazilian population, being responsible for a high rate of physical disability and reduced quality of life. Little has been discussed about the social factors associated with this health condition. This study aimed to analyze the social factors associated with OA in the Brazilian population. Methods: This is a cross-sectional study based on data from the 2013 National Health Survey in Brazil with OA as its main outcome. Gender, age, body weight, usual activities, physical activity, self-perceived health and diagnosis of depression were analyzed as independent variables. Descriptive and inferential statistics were used. Poisson multiple regression was performed, and the prevalence ratio (PR) and confidence interval (CI) of 95% were calculated using a significance level of 5% (p≤0.05). Results: A total of 60,202 individuals of both genders took part in this study and the OA prevalence was 6.4%. The individual factors associated with a higher prevalence of OA were female gender (PR = 2.09; CI = 1.95-2.25), age over 35 years (PR = 2.88; CI = 2.57-3.24) and excess body weight (PR = 1.61; CI = 1.25-2.07). The presence of OA showed an association with lower performance of usual activities (PR = 1.61; CI = 1.50-1.73) and self-perceived health as very poor (PR = 3.96; CI = 3.31-4.72). In addition, it was associated with a higher prevalence of mental illnesses such as depression (PR = 1.77; CI = 1.64-1.90). Conclusion: Social and modifiable factors which are associated with a higher prevalence of osteoarthritis can be controlled through incentive measures such as social participation and physical activity.