Physical Activity in Chileans with and without Knee and Hip Osteoarthritis in the Post-Pandemic Context

Abstract

The COVID-19 pandemic reduced physical activity levels and increased sedentary lifestyles due to worldwide confinement measures. This situation affected both healthy people and people suffering from chronic non-communicable diseases. However, people suffering from diseases in which mobility is affected, such as Osteoarthritis (OA), could be even more adversely affected by this situation. This thesis investigated physical activity levels in the Chilean context, considering sociodemographic variables and health characteristics in people suffering from OA and comparing healthy subjects with those suffering from this pathology. Four studies were carried out. The first of these articles sought to analyze whether there was a relationship between sociodemographic variables (sex, age, marital status, educational level, socioeconomic level, and type of work) and levels of physical activity (vigorous, moderate, and walking) reported by Chilean adults after the COVID-19 pandemic. Of the four hundred and eighty-six participants, 84 older adults were recruited in the second article, of which 42 had OA of the knee, hip, or both, and the rest were not diagnosed with the disease to compare the level of physical activity and quality of life. Some were part of the third and fourth articles, leaving 80 participants in total to examine whether health antecedents, physical activity, and sedentary behavior explain variations in the intensity of knee and hip osteoarthritis symptoms. Questionnaires were used, and information described in medical records was requested to assess activity levels, degree of severity, diagnosis of OA of the knee, hip, or both and whether it was bilateral or not, as well as the symptomatology of people with OA in terms of physical function, stiffness, and pain. The results suggest that men, younger people, those not cohabiting with a partner, those of lower socioeconomic status, and those working face-to-face performed higher physical activity. No differences were found when comparing physical activity levels between older adults with OA and those without. However, people with OA reported a better quality of life than those with OA. In turn, those with OA reported that their quality of life was better when they walked more. When specifically analyzing the relationship between the health history of hip and knee OA sufferers and their symptoms with physical activity levels in the third and fourth studies, it was found that physical functionality was explained by bilateral involvement, pain level, and OA severity when they performed lower levels of physical activity. Specifically, higher levels of intense, moderate, and walking physical activity and lower levels of sedentary activity mediated the relationship between disease severity, bilaterality, and OA type with pain levels and physical function. On the other hand, stiffness was mainly explained by disease severity, mediated by physical activity and sedentary behavior. Further research is needed to explore the complex interactions between disease history, physical activity, and health outcomes in different populations, although the results of the research that composed this doctoral thesis contribute to the literature on the promotion of physical activity to reduce sedentary behavior in the Chilean population with or without OA in the post-pandemic period.