Dose-dependent effect of rosuvastatin treatment on urinary protein excretion.

Concerns have been raised because of observations of proteinuria associated with rosuvastatin treatment. In this open-label study, a potential dose-dependent effect was investigated of rosuvastatin on urinary protein excretion and renal function parameters in 90 hyperlipidemic patients randomly assigned to rosuvastatin 10 mg/day (n = 45) or 20 mg/day (n = 45). Urinary samples were collected from patients and 40 age- and gender-matched controls to determine electrolyte, uric acid, creatinine, and protein (total, albumin, IgG, and alpha1-microglobulin) levels at baseline and after 12 weeks. A dose-dependent increase in the excretion of alpha1-microglobulin (17.6% in rosuvastatin 10 vs 34.9% in rosuvastatin, 20 mg/day; P = .03 for the comparison between groups) was observed. A trend toward an increase in the estimated glomerular filtration rate was noted in only patients receiving 20 mg/day of rosuvastatin. These findings indicate that rosuvastatin treatment increases the urinary excretion of alpha1-microglobulin urinary excretion in a dose-dependent manner without adversely affecting renal function.