The combination of OLmesartan and a CAlcium channel blocker (azelnidipine) or candesartan and a calcium channel blocker (amlodipine) in type 2 diabetic hypertensive patients: The OLCA study

Angiotensin II receptor blockers (ARB) are often co-administered with a calcium channel blocker (CCB) for treating hypertension. In this open-label randomised study, untreated diabetic hypertensive patients were randomised to receive either olmesartan 20 mg/day or candesartan 8 mg/day for 12 weeks. Patients with blood pressure exceeding 130/80 mm Hg received add-on 16 mg/day azelnidipine to ongoing olmesartan (OL group) or 5 mg/day amlodipine to ongoing candesartan (CA group) for 24 weeks. Home-measured and clinic-measured blood pressure decreased in both groups. Fasting blood glucose, haemoglobin A1c (HbA1c) and urinary albumin levels decreased significantly in the OL group but not in the CA group. In conclusion, this study revealed clinically relevant differences between two combinations of an ARB+CCB in diabetic hypertensive patients. Olmesartan and azelnidipine had a more persistent early morning antihypertensive effect and produced greater decreases in heart rate, fasting blood glucose and HbA1c (National Glycohemoglobin Standardization Program values) levels, and microalbuminuria than did candesartan and amlodipine.