Effect of telmisartan on the proteinuria and circadian blood pressure profile in chronic renal patients.

Telmisartan is a type 1 angiotensin II (AT(1)) receptor blocker, effective and safe in the treatment of arterial hypertension. However, data with respect to circadian blood pressure (BP) monitoring and urinary protein (uP) excretion are lacking in normotensive or mild hypertensive patients with chronic renal diseases. This study has evaluated the effects of 80 mg telmisartan, given as monotherapy, on 24 h BP levels and uP loss in 16 non-diabetic patients affected by proteinuric renal disease. These patients did not meet the recommended values of mean BP, i.e. < 98 mmHg, when proteinuria was 0.5-1.0 g/d and mean BP < 92 mmHg, when proteinuria was 1-3 g/d. Patients with diastolic BP > 114 mmHg, nephrotic syndrome or severe renal failure (creatinine clearance < 20 ml/min) were excluded. After 4.2 +/- 2.7 month therapy, ambulatory BP monitoring showed a significant decrease (P < 0.001) of 24 h BP levels: systolic 135 +/- 11 vs. 122 +/- 13 mmHg, diastolic 84.4 +/- 8.1 vs. 75.9 +/- 8.5 mmHg, mean 101 +/- 8 vs. 91 +/- 9 mmHg. The effect was quite evident during either day-time or night-time. Clinic BP levels also significantly decreased (P < 0.001), and five patients reached the target values. uP excretion lowered by 37% (median) from 1.60 +/- 0.90 to 1.06 +/- 0.63 g/24 h (P < 0.01). No change in creatinine clearance (53.3 +/- 31.1 vs. 51.7 +/- 30.9 ml/min) or serum potassium level (4.3 +/- 0.3 vs. 4.4 +/- 0.4 mEq/l) was observed. Our results show that 80 mg of telmisartan, taken once daily, is effective in reducing uP excretion and BP throughout the 24 h, in normotensive or mild hypertensive renal patients. Since evidence exists that adequate control of BP, including during night-time, and reduction of proteinuria play a crucial role in the protection of renal function, telmisartan can be usefully considered in the conservative treatment of renal patients.