The Irbesartan type II diabetic nephropathy trial: study design and baseline patient characteristics. For the Collaborative Study Group.
BACKGROUND
Diabetic nephropathy is the most common cause of end-stage renal disease in the developed world. Angiotensin-converting enzyme inhibitors have been demonstrated to be renoprotective in type I diabetes and are now the standard of care for both hypertensive and non-hypertensive type I diabetic patients with any level of proteinuria. The role of blockade of the renin-angiotensin system in type II diabetic patients is not defined. The Collaborative Study Group has initiated the Irbesartan Type II Diabetic Nephropathy Trial (IDNT), studying the effect of the angiotensin II receptor antagonist irbesartan on progression of renal disease and mortality in type II diabetic patients with overt nephropathy and hypertension. Here we report the study design and baseline patient characteristics.


METHODS
To qualify, hypertensive type II patients, age 30-70 years, must have a 24 h urinary protein excretion of >900 mg and a serum creatinine 90-265 micromol/l (1.0-3. 0 mg/dl) in women and 110-265 micromol/l (1.2-3.0 mg/dl) in men. Three treatment arms include irbesartan, placebo and amlodipine, with every attempt made to achieve similar blood pressure levels in all treatment arms. A total of 1650 patients will be enrolled utilizing approximately 225 clinics worldwide. The primary outcome measure is time to event to the composite end-point of doubling of serum creatinine, end-stage renal disease or death. The secondary outcome measure is time to composite end-point of fatal or non-fatal cardiovascular events. The average length of patient follow-up is expected to be approximately 36 months.


RESULTS
The baseline characteristics of the study subjects are: age 59+/-8 years, duration of diabetes 15+/-9 years, height 168+/-11 cm (5 ft 6 in), weight 87+/-19 kg (192 lb), body mass index 31+/-7 kg/m(2), blood pressure 156+/-18 mmHg/85+/-11 mmHg, serum creatinine 150+/-53 micromol/l (1.7+/-0.6 mg/dl), creatinine clearance 66+/-34 ml/min and 24 h urine protein 4.0+/-3.5 g/day.
Rodby
R A
RA
The Section of Nephrology, Department of Medicine, Rush Medical College, Chicago, IL, USA.
Rohde
R D
RD
Clarke
W R
WR
Hunsicker
L G
LG
Anzalone
D A
DA
Atkins
R C
RC
Ritz
E
E
Lewis
E J
EJ
D000328:Adult; D000368:Aged; D017311:Amlodipine / Q000627:therapeutic use*; D057911:Angiotensin Receptor Antagonists; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001713:Biphenyl Compounds / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000627:therapeutic use*; D003404:Creatinine / Q000097:blood / Q000652:urine; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy* / Q000378:metabolism / Q000401:mortality; D003928:Diabetic Nephropathies / Q000188:drug therapy* / Q000378:metabolism / Q000401:mortality; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D000077405:Irbesartan; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012107:Research Design; D015996:Survival Rate; D013777:Tetrazoles / Q000627:therapeutic use*; D016896:Treatment Outcome
D057911:Angiotensin Receptor Antagonists; D000959:Antihypertensive Agents; D001713:Biphenyl Compounds; D002121:Calcium Channel Blockers; D013777:Tetrazoles; D017311:Amlodipine; D003404:Creatinine; D000077405:Irbesartan