Association between socioeconomic status and comorbidities among patients with rheumatoid arthritis: results of a nationwide cross-sectional survey

• Published in: Rheumatology (Oxford, England) Vol. 58; no. 9; pp. 1617 - 1622
• Main Authors: Shin, Anna, Shin, Seunghwan, Kim, Ji Hyoun, Ha, You-Jung, Lee, Yun Jong, Song, Yeong Wook, Kang, Eun Ha
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 01-09-2019; Oxford Publishing Limited (England)
• Subjects: Adult; Age; Age Factors; Aged; Arthritis; Arthritis, Rheumatoid - epidemiology; Comorbidity; Cross-Sectional Studies; Delivery of Health Care - statistics & numerical data; Diabetes mellitus; Diabetes Mellitus - epidemiology; Female; Health Behavior; Humans; Hypertriglyceridemia; Low income groups; Male; Mental Disorders - epidemiology; Middle Aged; Mood; Nutrition Surveys; Obesity - epidemiology; Osteoarthritis; Osteoarthritis - epidemiology; Republic of Korea - epidemiology; Rheumatoid arthritis; Risk Factors; Social Class; Socioeconomic Factors; Socioeconomic status; Suicide; Young Adult; Republic of Korea; rheumatoid arthritis; socioeconomic status; comorbidity
• ISSN: 1462-0324; 1462-0332
• DOI: 10.1093/rheumatology/kez081

Abstract
Objectives
We examined the association between socioeconomic status (SES) and comorbidity distribution among patients with RA.
Methods
Information on comprehensive health status of 1088 RA patients (weighted n = 612 303) was obtained from the 2007–2015 Korea National Health and Nutrition Examination Survey database. SES components were household equivalence income, education and area of residence. To minimize confounding by age, patients were stratified by median age (63 years). Age-adjusted odds ratio (OR) with 95% confidence interval (95% CI) was estimated, comparing weighted prevalence of individual comorbidities between low and high SES groups in each age stratum.
Results
Among RA patients aged <63 years (mean 49 years, 70% female), we observed age-adjusted associations of depression (OR 2.13, 95% CI 1.01, 4.53), depressive mood (OR 2.68, 95% CI 1.54, 4.65), suicide ideation (OR 3.01, 95% CI 1.79, 5.07), diabetes (OR 3.09, 95%CI 1.31, 7.29), obesity (OR 2.04, 95% CI 1.30, 3.20), hypertriglyceridemia (OR 2.36, 95% CI 1.28, 4.34) and osteoarthritis (OR 2.12, 95% CI 1.13, 3.99) with low income, of suicide ideation with low education (OR 2.25, 95% CI 1.14, 4.44), but no association of any comorbidities with area of residence. Unhealthy behavior patterns were comparable between low- and high-income groups but patients with low income reported a numerically higher rate of failed access to necessary healthcare services. We did not find any association between SES and comorbidities among those aged ⩾63 years (mean 72 years, 83% female).
Conclusion
Among Korean RA patients aged <63 years, socioeconomic inequalities of multiple comorbidities in mental, cardiometabolic and musculoskeletal systems were found.