Early ACE-I intervention in microalbuminuric patients with type 1 diabetes: effects on albumin excretion, 24 h ambulatory blood pressure and renal function

Objectives: To study the effects of ACE-i in type 1 diabetic patients with early microalbuminuria with regard to: i) UAE, ii) 24 h AMBP, including the effect on diurnal BP variation, and iii) renal haemodynamics. Material and Methods: 58 patients with urinary albumin excretion (UAE) betw een 20-70 mug/min were treated for two years with either the ACE inhibitor (ACE-II lisinopril (20 mg od)or placebo in two randomised placebo controlle d double blind studies. In a subgroup of patients (n = 22) we performed 24 h ambulatory blood pressure measurements (AMBP) and renal function tests(co nstant infusion technique). Results: i) Changes in UAE over the two years were significantly different (p < 0.01) in the two groups with final UAE in the lisinopril group of 19.1 <mu>g/min x/divided by 2.5 (geometric mean xi; tolerance factor) and 44.1 mug/min x/divided by 2.8 in the placebo group. In the lisinopril group 20 p atients (60.6%) reversed to normoalbuminuria compared to 6 patients (24%) i n the placebo group (p<0.02), ii) Clinical BP measurements revealed no diff erences between groups, but by AMBP significant reductions were detectable in the lisinopril group, primarily in night AMBP (systolic/diastolic: - 6.9 +/- 8.6/- 6.0 +/- 5.3 mmHg, p < 0.01)as opposed to increases in the placeb o group (3.1 +/- 9.3/1.9 +/- 7.3 mmHg). iii) Chang es in UAE and changes in filtration fraction (FF) were positively correlated in the intervention gr oup (r = 0.9 p < 0.01), i.e, the patients who showed the greatest fall in U AE were the ones with the greatest fall in FF. Conclusions: ACE-i treatment in patients with low-grade microalbuminuria re duces 24 h AMBP without attenuating diurnal blood pressure variation, reduc es UAE significantly, with changes in UAE being strongly associated with ch anges in FF. Furthermore, compared to placebo, ACE-i reverses micro- to nor moalbuminuria in a significant fraction of patients.