Aim: To determine the relationship of steroid use with tophus formation and other comorbid conditions among male gout patients.
Methods: Review of medical records of Filipino gout patients under the care of rheumatologists was conducted. Univariate analysis (chi-square, Student's t-test) and multiple logistic regression analysis were performed to establish the risk for tophus formation among glucocorticoid users. Bivariate analysis was separately done to determine the confounding effect of steroid use in the association of comorbidities and tophi formation.
Results: There were 295 Filipino men with a mean age of 56 years and a mean duration of 12 years of gouty arthritis who were included in the study. Multivariate analysis showed a five times higher likelihood (OR 4.81 95% CI 1.92-12.04, P < 0.001) for tophus formation among prolonged steroid users. Confounders identified were disease duration of gout (> or = 10 years), presence of chronic kidney disease (CKD) and elevated serum creatinine level (SCr). Bivariate analysis of comorbidities showed that steroid use introduced a considerable bias in the relationship of hypertension, elevated SCr, CKD and dyslipidemia.
Conclusion: Patients with equivalent prednisone intake of at least 15 mg/week for > or = 3 months is associated with tophi formation. In the presence of hypertension, renal impairment, and elevated serum creatinine level, use of steroids confounds the individual risk that each factor carries.