Reduction of proteinuria by pioglitazone in patients with non-diabetic renal disease

BACKGROUND: Increased proteinuria would lead to a larger risk for renal failure in the long term. Therefore, proteinuria requires immediate and thorough evaluation. This study was designed to evaluate the effects of pioglitazone on proteinuria in patients with non-diabetic renal disease. METHODS: In this self-controlled clinical trial study, forty four non-diabetic patients aged 18 and more, who had renal disease and a stable proteinuria of over 0.5 g in 24 hour, were studied. All patients received 15 mg of daily pioglitazone for 4 months. Urine protein excretion was measured as a main end point prior to the study, at the end of the 2nd and 4th months of treatment, and 2 and 4 months after the cessation of the active drug. Other evaluated variables included systolic blood pressure, serum creatinine, urea, alanine aminotransferase (ALT), aspartate aminotransferase (AST), fasting blood sugar (FBS), blood urea nitrogen (BUN) and glomerular filtration rate (GFR) levels. RESULTS: Proteinuria (mean ± SEM) prior to the study, at the 2nd and 4th months of the treatment, and 2 and 4 months after the cessation of pioglitazone were 1088.6 ± 131.1, 699.9 ± 118.3, 433.9 ± 68.7, 416.1 ± 54.9 and 646.9 ± 89.1, respectively (p < 0.001). In addition, the reduction of 24-hour urine protein was statistically significant for both male and female patients (p < 0.001 for both). CONCLUSIONS: A reduction of proteinuria in patients with non-diabetic renal disease was observed during the 4-month treatment with pioglitazone which continued for 2 months after the cessation of the treatment. However, 4 months after the cessation of the treatment, a little increase was detected in the level of proteinuria.