Beneficial Effect of Combination Therapy by Losartan and Azelnidipine on Albuminuria and Renal Function in Type 2 Diabetic Patients With Chronic Kidney Disease

Elevated urinary albumin excretion rate（UAER) is a modifiable risk factor for renal and cardiovascular diseases in type 2 diabetes. Blockade of the renin-angiotensin system（RAS）lowers UAER. In the present study, 46 patients（male: 25, female: 21, mean age 62.8±5.9 years old）with CKD and hypertension accompanied with type 2 diabetes were
enrolled, among whom there were wide ranges of blood-pressure values. Patients had been used amlodipine or nifedipine to control blood pressure between 2007 and 2009 at Nagami Clinic, Shimane Japan. However, UAER did not decrease and estimated glomerular filtration rate（eGFR）did not increase during the first 24 month follow up period. To those 46 patients, losartan which is one of angiotensin receptor blockers（ARBs）and azelnidipine which is one of calcium channel blockers（CCBs）were administered in order to examine whether combined administration of losartan and azelnidipine（Los/Azl treatment）provides superior reduction in proteinuria compared to nifedipine or amlodipine in hypertensive type 2 diabetes patients with CKD. All 46 patients received
either 25 mg per day losartan, which was increased up to 50 mg per day, and 8 mg per day azelnidipine, which was increased up to 16mg per day, over 24 months. Mean systolic and diastolic pressure was controlled less than 120/80 mmHg. This present study
was a 2 years’prospective cohort study. During the first 24 month follow up period, there was not a significant difference of the mean eGFR and UAER between amlodipine group and nifedipine group. However, the present changes in eGFR and UAER by Los/Azl treatment at 6, 12, 18 and 24 month showed 5.4, 7.0, 9.0, and 13.2 % for eGFR and -15.2, -24.8, -37.3, and -48.7% for UAER, respectively. In conclusion, it was demonstrated that Los/Azl treatment should be considered for hypertensive diabetic
patients with CKD.