Blood pressure-lowering and antiproteinuric effect of switching from high-dose angiotensin receptor blockers to normal-dose telmisartan and low-dose hydrochlorothiazide in hypertensive patients with chronic kidney disease

Abstract

We evaluated the changes in the blood pressure and urinary protein excretion in poorly controlled hypertensive and proteinuric patients with mild to moderate chronic kidney disease (CKD) after switching from the high-dose angiotensin receptor blockers (ARBs) to a combination of normal-dose telmisartan (40 mg) and low-dose hydrochlorothiazide (HCTZ; 12.5 mg). 60 adults with Stages 2 - 3 CKD who had been receiving high-dose ARBs and had not achieved their target blood pressure of 130/80 mmHg were switched to a combination of telmisartan (40 mg) and HCTZ (12.5 mg) once daily for a 12-week study period. We measured the blood pressure, pulse rate, urinary protein excretion, and total monthly drug costs before and after the switch. The mean systolic blood pressure dropped from 153 to 133 mm Hg and the mean diastolic blood pressure, from 89 to 78 mmHg (p < 0.0001, for both). Further, the mean blood pressure decreased (p < 0.0001), without any significant change in the pulse rate. Urinary protein excretion adjusted for urinary creatinine was reduced from 3,749 to 2,474 mg/g creatinine (p < 0.0001). No significant change was detected in the estimated glomerular filtration rate and serum creatinine level. With the switching from high-dose ARBs to the combination of normal-dose telmisartan and low-dose HCTZ treatment, the blood pressure decreased in all the subjects, and 36% of all the subjects achieved optimal blood pressure levels. No adverse metabolic effects were noted even among the diabetic patients. The monthly drug costs were significantly reduced after the switch (13,614 +/- 6,108 vs. 9,936 +/- 5,571 yen/month, p < 0.0001). We concluded that the telmisartan and HCTZ combination may be more efficacious than monotherapy of the high-dose ARBs in reducing blood pressure and urinary protein excretion in hypertensive patients with CKD. Further investigation would be required to assess whether the combination of high-dose ARBs and low-dose HCTZ has a greater antiproteinuric effect than the combination of normal-dose telmisartan (40 mg) and low-dose HCTZ (12.5 mg).