Osteoarthritis affects health-related quality of life in Korean adults with chronic diseases: The Korea National Health and Nutritional Examination Surveys 2009-2013

Background: Osteoarthritis (OA) is a chronic disease that commonly afflicts the elderly. This disease reduces the health-related quality of life (HRQoL) and causes a significant social burden. Whether the effect of coexisting chronic conditions on HRQoL varies according to the presence of OA remains unclear. Therefore, this study aimed to investigate this notion. Methods: A total of 13,395 participants were identified from the 2009-2013 Korean National Health and Nutrition Examination Survey for analysis. HRQoL was assessed using the European quality of life-5 dimensions (EQ-5D) index. Patients with OA were defined as those diagnosed by a physician or those who displayed both, symptoms and radiological findings consistent with OA at the time of the survey. Associations between OA and 8 chronic conditions were tested using regression analysis. Results: The EQ-5D index was lower in patients with OA than in those without (mean difference, -0.145; 95% confidence interval [CI], -0.138 to -0.151; P < 0.001). Most patients with OA and chronic conditions showed a lower score than those without. EQ-5D was particularly lower in OA patients with hypertension, dyslipidemia, stroke, and renal failure. The estimated β coefficient for the interaction term was significant in renal failure (-0.034; 95% CI, -0.055 to -0.012), after adjusting for demographic and socio-economic variables. Conclusion: OA significantly affects HRQoL of Korean elderly individuals alone or when combined with other conditions. OA combined with renal failure is particularly detrimental. These results indicate the importance of managing OA, which is an underestimated disease in public health surveys.