Arthritis: its prevalence, risk factors, and association with cardiovascular diseases in the United States National Health and Nutrition Examination Survey 1999-2008

Abstract

INTRODUCTION: Arthritis is associated with cardiovascular diseases (CVDs). However, there are limited studies on arthritis in a national representative sample. We therefore investigated the prevalence of arthritis, and whether cardiovascular risk factors were associated with arthritis. The results show an interaction effect on the association of arthritis with CVDs. METHODS: Data from 15888 subjects aged 40 years in the United States National Health and Nutrition Examination Survey 1999-2008 were analyzed. RESULTS: The overall prevalence of self-reported arthritis increased from 33.5% in 1999-2000 to 37.0% in 2007-2008 (P for trend=0.016), especially in subjects aged 40-49 years, men, non-Hispanic whites, and obese subjects (P=0.045, 0.015, 0.016, and 0.017 respectively). Among subjects with arthritis in 1999-2008, 35.3% had osteoarthritis (OA), 17.9% had rheumatoid arthritis (RA), and 10.2% had other types of arthritis, but 36.6% were unaware of their type of arthritis. Risk factors such as age, gender, BMI, smoking, hypertension, education, alcohol drinking, total cholesterol, CRP, and biomarkers of liver injury were associated with OA, RA, or both. Being non-Hispanic black was associated with higher odds of RA, but lower odds of OA (both P<0.01). About 20.9% and 27.2% of subjects with OA and RA had self-reported CVDs (heart attack, congestive heart failure, coronary heart disease, angina, and/or stroke) respectively. OA was associated with CVDs (adjusted OR=1.57, P<0.001), especially angina (adjusted OR=2.26, P<0.001), and showed interaction with total cholesterol (P=0.032) with adjusted ORs for CVDs being 1.09, 1.37, 2.07, and 2.50 in subjects with total cholesterol in sex-specific quartiles 1, 2, 3, and 4 respectively. RA was associated CVDs (adjusted OR=2.39, P<0.001), especially congestive heart failure (adjusted OR=3.62, P<0.001) and showed interaction with HDL cholesterol (P=0.012) with adjusted ORs for CVDs being 2.06, 2.42, 2.28, and 3.12 in subjects with HDL cholesterol in sex-specific quartiles 1, 2, 3, and 4 respectively. CONCLUSION: The prevalence of arthritis has increased significantly in recent years. Patients with arthritis and their doctors should be aware of the increased risk of cardiovascular disease.