S Wang1, M H Pillinger2, S Krasnokutsky3, K E Barbour4. 1. Division of Rheumatology, Department of Medicine, Montefiore Medical Center/Albert Einstein College of Medicine, Bronx, NY, USA; Crystal Diseases Study Group, Division of Rheumatology, New York University School of Medicine, New York, NY, USA; VA New York Harbor Health Care System, New York Campus, New York, NY, USA. Electronic address: shudanwang87@gmail.com. 2. Crystal Diseases Study Group, Division of Rheumatology, New York University School of Medicine, New York, NY, USA; VA New York Harbor Health Care System, New York Campus, New York, NY, USA. Electronic address: michael.pillinger@nyulangone.org. 3. Crystal Diseases Study Group, Division of Rheumatology, New York University School of Medicine, New York, NY, USA. Electronic address: svetlana.krasnokutsky@nyulangone.org. 4. Centers for Disease Control and Prevention, Atlanta, GA, USA. Electronic address: iyk1@cdc.gov.
Abstract
OBJECTIVE: In vitro and clinical studies suggest that urate may contribute to osteoarthritis (OA) risk. We tested the associations between hyperuricemia and knee OA, and examined the role of obesity, using a cross-sectional, nationally representative dataset. METHOD: National Health and Nutrition Examination Survey (NHANES) III used a multistage, stratified probability cluster design to select USA civilians from 1988 to 1994. Using NHANES III we studied adults >60 years, with or without hyperuricemia (serum urate > 6.8 mg/dL), excluding individuals with gout (i.e., limiting to asymptomatic hyperuricemia (AH)). Radiographic knee OA (RKOA) was defined as Kellgren-Lawrence grade ≥ 2 in any knee, and symptomatic radiographic knee osteoarthritis (RKOA) (sRKOA) was defined as RKOA plus knee pain (most days for 6 weeks) in the same knee. RESULTS: AH prevalence was 17.9% (confidence interval (CI) 15.3-20.5). RKOA prevalence was 37.7% overall (CI 35.0-40.3), and was 44.0% for AH vs 36.3% for normouricemic adults (p = 0.056). symptomatic radiographic knee osteoarthritis (sRKOA) was more prevalent in AH vs normouricemic adults (17.4% vs 10.9%, p = 0.046). In multivariate models adjusting for obesity, model-based associations between AH and knee OA were attenuated (for RKOA, prevalence ratio (PR) = 1.14, 95% CI 0.95, 1.36; for sRKOA, PR = 1.40, 95% CI 0.98, 2.01). In stratified multivariate analyses, AH was associated with sRKOA in adults without obesity (PR = 1.66, 95% CI 1.02, 2.71) but not adults with obesity (PR = 1.21, 95% CI 0.66, 2.23). CONCLUSIONS: Among adults aged 60 or older, AH is associated with knee OA risk that is more apparent in adults without obesity. Published by Elsevier Ltd.
OBJECTIVE: In vitro and clinical studies suggest that urate may contribute to osteoarthritis (OA) risk. We tested the associations between hyperuricemia and knee OA, and examined the role of obesity, using a cross-sectional, nationally representative dataset. METHOD: National Health and Nutrition Examination Survey (NHANES) III used a multistage, stratified probability cluster design to select USA civilians from 1988 to 1994. Using NHANES III we studied adults >60 years, with or without hyperuricemia (serum urate > 6.8 mg/dL), excluding individuals with gout (i.e., limiting to asymptomatic hyperuricemia (AH)). Radiographic knee OA (RKOA) was defined as Kellgren-Lawrence grade ≥ 2 in any knee, and symptomatic radiographic knee osteoarthritis (RKOA) (sRKOA) was defined as RKOA plus knee pain (most days for 6 weeks) in the same knee. RESULTS:AH prevalence was 17.9% (confidence interval (CI) 15.3-20.5). RKOA prevalence was 37.7% overall (CI 35.0-40.3), and was 44.0% for AH vs 36.3% for normouricemic adults (p = 0.056). symptomatic radiographic knee osteoarthritis (sRKOA) was more prevalent in AH vs normouricemic adults (17.4% vs 10.9%, p = 0.046). In multivariate models adjusting for obesity, model-based associations between AH and knee OA were attenuated (for RKOA, prevalence ratio (PR) = 1.14, 95% CI 0.95, 1.36; for sRKOA, PR = 1.40, 95% CI 0.98, 2.01). In stratified multivariate analyses, AH was associated with sRKOA in adults without obesity (PR = 1.66, 95% CI 1.02, 2.71) but not adults with obesity (PR = 1.21, 95% CI 0.66, 2.23). CONCLUSIONS: Among adults aged 60 or older, AH is associated with knee OA risk that is more apparent in adults without obesity. Published by Elsevier Ltd.