[Effect of metformin on the clinical course of gout and insulin resistance].

UNLABELLED: The aim of this prospective study was to evaluate results of metformin (MF) therapy during 1 year of uric acid (UA) metabolism and the clinical course of gout with insulin resistance (IR). The study included 30 patients (28 men and 2 women) of mean age 51 yr and duration of he disease 4-11 yr. IR was diagnosed based on the HOMA index. INCLUSION CRITERIA: the absence of anti-gout therapy, normal renal and hepatic function, abstinence. The patients were given 1500 mg MF/day. The measured parameters included anthropometric and clinical characteristics, 24 hour AP, plasma UA, glucose, insulin, urea, creatinine, ALT, AST, lipid spectrum at the first and subsequent visits. UA clearance and excreted UA fraction were calculated. UA level decreased from 569 +/- 109.5 to 442.8 +/-107.4 mcmol/l (p < 0.01) after 12 months of MF therapy. Normouricemia ( < 360 mcmol/l) was achieved in 11 patients. Fasting insulin level dropped by 35% (from 23.9 to 15.9 mcU/ml, p < 0.01), HOMA index from 6.5 to 3. 7(p < 0.01). Serum glucose, cholesterol, triglycerides, and LDL cholesterol decreased while HDL cholesterol increased. Parameters of renal UA regulation and anthropometry remained unaltered. MF therapy resulted in a decrease of serum UA, insulin, and the degree of IR. The hypouricemic effect of MF was unrelated to renal UA excretion, reduced AP and body weight. It is hypothesized that MF reduces production of UA in patients with gout due to inhibition of synthesis of free fatty acids.