Does ACE inhibition slow progression of glomerulopathy in patients with Type 2 diabetes mellitus?

Aims To examine the effect of ACE inhibition on glomerular structure in Type 2 diabetic patients with nephropathy. Methods Twenty-two patients were randomized to receive either perindopril (PE) or placebo (PO) and biopsied at baseline and after 2 years. Nineteen patients completed the study and data on interstitial changes, examined by light microscopy, have already been published. Only 11 patients (five PE, six PO) had sufficient tissue at baseline and follow-up to provide material for detailed electron microscopic examination. Results At baseline, mean SD age (PE vs. PO) was 48 +/- 12 vs. 45 +/- 7 years; creatinine clearance 116 +/- 24 vs. 128 +/- 68 ml/min; median (range) proteinuria 0.7 (0.1-1.0) vs. 0.5 (0.07-3.9) g/24 h (P = NS for all). This cohort of 11 patients showed the same interstitial changes as the whole group. Between-group analysis showed that the change in interstitial volume fraction was significantly greater in the PO compared with PE group (0.10 +/- 0.07 vs. -0.001 +/- 0.04, P = 0.020). There were no significant changes in proteinuria or glomerular structural parameters (mesangial volume fraction PO 0.40 +/- 0.17 to 0.42 +/- 0.21; PE 0.29 +/- 0.08 to 0.28 +/- 0.14) in either treatment group. Conclusions Interstitial changes appear to be more sensitive to ACE inhibition than glomerulopathy. Larger patient groups and longer treatment periods are necessary in order to detect any possible impact of ACE inhibition on the glomerular changes in Type 2 diabetes mellitus.