At the beginning of this trial, it was unknown whether or not ARBs reduce the progression of diabetic nephropathy independently of its capacity to lower blood pressure. This trial randomized 1715 hypertensive patients with chronic kidney disease attributed to type 2 diabetes. Patients where are eligible if they were between the ages of 30 and 70 years old, had hypertension with a blood pressure of greater than 135/85mmHg, had type 2 DM, and had a urinary protein excretion of at least 900 mg in 24 hours. The serum creatinine had to be 1.0-3.0 mg/dL in women and 1.2-3.0 mg/dL in men. Patients were randomized to irbesartan 300 mg daily or amlodipine 10mg daily or placebo. The target blood pressure was 135/85mmHg in all groups. The primary outcome was a composite of doubling of baseline serum creatinine, the onset of ESKD ( defined as the initiation dialysis, renal transplant, a serum creatinine concentration of at least 6.0mg/dL, or death from any cause). The median duration of follow-up was 2.6 years. Treatment with irbesartan was associated with a reduction of 20% of the primary composite endpoint as compared to placebo and wasv23% lower as compared to amlodipine. Overall, this trial gave us great information about the benefit of ARB use in diabetic nephropathy and dovetailed nicely with the results of the RENAAL Trial (2001) which showed that lostartan reduced the progression to ESKD of patients with diabetic nephropathy.
The IDNT Trial: Lewis, E. J., Hunsicker, L. G., Clarke, W. R., Berl, T., Pohl, M. A., Lewis, J. B., ... & Raz, I. (2001). Renoprotective effect of the angiotensin-receptor antagonist irbesartan in patients with nephropathy due to type 2 diabetes. New England Journal of Medicine, 345(12), 851-860.
The IDNT Trial PMID: 11565517
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