Relative incidence of ESRD versus cardiovascular mortality in proteinuric type 2 diabetes and nephropathy: results from the DIAMETRIC (Diabetes Mellitus Treatment for Renal Insufficiency Consortium) database

Background: Previous studies have shown that patients with chronic kidney disease, including those with diabetic nephropathy, are more likely to die of cardiovascular disease than reach end-stage renal disease (ESRD). This analysis was conducted to determine whether ESRD is a more common outcome than cardiovascular death in patients with type 2 diabetic nephropathy, significant proteinuria, and decreased kidney function who were selected for participation in a clinical trial.

Study design: Retrospective analysis of the DIAMETRIC (Diabetes Mellitus Treatment for Renal Insufficiency Consortium) database derived from 2 prospective randomized controlled clinical trials (IDNT [Irbesartan Diabetic Nephropathy Trial] and RENAAL [Reduction of Endpoints in Non-Insulin-dependent Diabetes With the Angiotensin II Antagonist Losartan]).

Setting & participants: 3,228 adult patients with type 2 diabetic nephropathy from IDNT and RENAAL were combined to establish the DIAMETRIC database. This is the largest global source of clinical information for patients with type 2 diabetic nephropathy who have decreased kidney function and significant proteinuria.

Intervention: Angiotensin receptor blocker versus non-angiotensin receptor blocker therapy to slow the progression of type 2 diabetic nephropathy (in the prospective trials).

Outcomes & measurements: Incidence rates of ESRD, cardiovascular death, and all-cause mortality.

Results: Mean follow-up was 2.8 years; 19.5% of patients developed ESRD, approximately 2.5 times the incidence of cardiovascular death and 1.5 times the incidence of all-cause mortality. ESRD was more common than cardiovascular death in all subgroups analyzed with the exception of participants with low levels of albuminuria (albumin excretion <1.0 g/g) and well-preserved levels of kidney function (estimated glomerular filtration rate >45 mL/min/1.73 m(2)) at baseline.

Limitations: All participants were included in a prospective clinical trial.

Conclusions: Patients with type 2 diabetic nephropathy, characterized by decreased kidney function and significant proteinuria, are more likely to reach ESRD than die during 3 years' mean follow-up. Given the rapidly increasing number of cases of type 2 diabetes worldwide, this has implications for predicting future renal replacement therapy requirements.