Long-term renoprotective effects of standard versus high doses of telmisartan in hypertensive nondiabetic nephropathies

Background: This report describes an open randomized study intended to evaluate the long-term renoprotective effects of standard (80 mg once daily) versus high (80 mg twice daily) doses of telmisartan in hypertensive patients without diabetes with biopsy-proven chronic proteinuric nephropathies. Methods: We included 78 patients (age, 43.5 +/- 13.2 years; 71.8% men). After a 4-week wash-out period, patients were randomly assigned to telmisartan, 80 mg once daily (n = 40) or 80 mg twice daily (n = 38), during a mean follow-up of 24.6 +/- 2.2 months. Results: Baseline characteristics were similar in both groups, including blood pressure, renal function, and proteinuria. Blood pressure control did not differ between groups during follow-up. In the group administered telmisartan, 80 mg once daily, serum creatinine level increased from 1.6 +/- 0.6 to 2.7 +/- 0.9 mg/dL (141 +/- 52 to 239 80 mu mol/L), and estimated creatinine clearance declined from 68 +/- 30 to 50 +/- 34 mL/min (1.13 +/- 0.50 to 0.83 +/- 0.57 mL/s), whereas in those administered 80 mg twice daily, serum creatinine (1.6 +/- 0.7 to 1.6 +/- 0.8 mg/dL [141 +/- 62 to 141 +/- 71 mu mol/L]) and estimated creatinine clearance values (67 +/- 38 to 74 +/- 38 mL/min [1.12 +/- 0.63 to 1.23 +/- 0.63 mL/s]) did not change during the study. The decrease in proteinuria was more pronounced (P < 0.01) in patients administered the high dose of telmisartan compared with those treated with the standard dose. Serum potassium levels and lipid profiles did not change significantly in either group. Conclusion: Long-term administration of high doses of telmisartan seems to improve the efficacy of the drug to decrease proteinuria and slow the progression to end-stage renal failure in nondiabetic hypertensive renal disease.