Osteoarthritis (OA) among older men with gout was prevalent and tended to be more severe when compared with a group of older men without gout, according to recently published data.
Researchers studied 75 men between the ages of 55 and 85 years from a Veteran’s Affairs clinic, 25 of whom had gout, 25 had asymptomatic hyperuricemia (AH) and 25 had neither. Age and race were similar in each group, but patients in the gout group were more likely to have higher BMI and less likely to report smoking. Patients were excluded in the presence of chondrocalcinosis, hemochromatosis, hemodialysis, inflammatory arthritis, inflammatory bowel disease, psoriasis, total knee replacement or history of severe knee trauma.
Diagnosis was made based on American College of Rheumatology (ACR) Clinical/Radiographic and radiographic knee osteoarthritis (OA) severity measured by Kellgren-Lawrence (KL) grading. Knee OA was further evaluated by ACR Clinical Criteria, the frequency of bilateral knee OA, RAPID3 and WOMAC scores. Serum uric acid (sUA) levels and the estimated glomerular filtration rate (eGFR) were measured at the first visit. At the second follow-up visit, patients completed the RAPID3 and WOMAC assessments and were evaluated by a rheumatologist for OA based on ACR criteria. Assessment of tophi was also performed at this time.
The eGFR was significantly lower in the group with gout compared with the control or AH groups. Cardiovascular disease and hypertension were also lower in the control group, but the differences did not reach statistical significance, according to the researchers.
The Knee Activity Score was similar among all three groups, but sUA levels were higher in the AH and gout groups. No patients with gout reported disease flare at the time of study.
The group of patients with gout had the highest proportion of patients with OA (68%) compared with the AH group (52%) and the non-gout group (28%). Further, patients with gout were at a fivefold higher risk for OA in an unadjusted model.
Patients with OA in the group with gout had higher mean KL grades compared with the control group. Although patients with AH had KL grades between those of patients with and without gout, the difference was not statistically significant, according to the researchers. The highest WOMAC scores were seen in the patients with gout.
After adjusting for BMI using multivariate regression, education level and eGFR were not associated with the prevalence of knee OA. Increased BMI was associated with higher odds of ACR clinical or radiologic OA and ACR criteria for knee OA regardless of the presence of gout or AH, but the odds for OA remained higher in the group with gout, according to the researchers. - by Shirley Pulawski
Disclosure: The researchers report no relevant financial disclosures.