Factors associated with musculoskeletal disability and chronic renal failure in clinically diagnosed primary gout

. To assess the association between a set of sociodemographic, clinical, and biochemical variables and the presence of musculoskeletal (MSK) disability and chronic renal failure in patients with primary gout defined using Wallace criteria.

Subjects were 90 patients with primary gout (98% male, age 54 +/- 12 years, 11.3 +/- 9.8 years with gout). A cohort nested case-control design was used. Analysis was done of the association between MSK disability or renal failure and a series of variables: age; duration of gout; body mass index; education level; income; serum glucose, cholesterol, triglycerides, and uric acid; Health Assessment Questionnaire score; obesity; family history of gout; high blood pressure; alcoholism; smoking habit; presence of tophi; ischemic cardiopathy; and use of colchicine, glucocorticoids, nonsteroidal antiinflammatory drug, or allopurinol.

Forty-two patients (47%) had MSK disability, and 25/80 (31%) had renal failure. On logistic regression, presence of tophi (relative risk 4.3, 95% confidence interval 1.2-15.1), hypertriglyceridemia (RR 3.4, 95% CI 1.1-10), and history of ischemic heart disease (RR 8.3, 95% CI 1.6-41) were associated with MSK disability. Patient age was the only variable associated with renal failure.

Optimal medical control of gout and its comorbidities may improve prognosis of gout, as suggested by our findings, in which a marker for poorly controlled gout such as presence of tophi in addition to high blood triglyceride levels and ischemic heart disease were associated with MSK disability. Older age was the only factor associated with renal failure, although this may only reflect declining renal function in the elderly.