The effects of angiotensin converting enzyme ingibitors on proteinuria and lipoprotein(a) in non-insulin dependent diabetic patients

Cho, Dong Hyeok; Chung, Min Young; Lee, Dae Ho; Shin, Hyun Ho; Lee, Yeon Sang; Kim, Jung Min; Kim, Yong Joo; Lee, Dae Bae; Chung, Dong Jin; Lee, Tai Hee

Abstract

BACKGROUND: We determined the serum Lipoprotein(a) [Lp(a)] level in patients with NIDDM and evaluated the relationship between serum Lp(a) level and proteinuria, and the efficacy of angiotensin converting enzyme inhibitor(ACEI) in reducing serum Lp(a) level in NlDDM patients. METHOD:A total of 86 patients with NlDDM(age: 61.2 +/- 1.2 years) was divided into ACEI treatment group (n=45) and control group(n=41). The changes of the amount of proteinuria and serum Lp(a) were analyzed in both groups. Mean duration of follow-up in control group or ACEI administration in ACEI group was 8.4 months.
RESULTS
1) Befare ACEI treatment, the positive correlation between serum Lp(a) level and amount of proteinuria was present in ACEI group, but not in total subjects and control group. ACEI treatment was associated with decrease in serum Lp(a) level, but not with change in the amounts of proteinuria. 2) Serum Lp(a) levels decreased significantly by ACEI treatment, not only in patients whose diastolic blood pressure(DBP) decreased by more than 10mmHg, but also in patients whose DBP did not response to ACEI administration. 3) Patients with overt proteinuria(> 500rng/day) had higher serum Lp(a) level than patients without overt proteinuria before ACEI treatment. After ACEI treatment, serum Lp(a) levels and amount of proteinuria decreased significantly in patients with overt proteinuria, but not in patients without overt proteinuria. 4) In both subgroups of patients with serum Lp(a) level 30mg/dl and patients with serum Lp(a) level <30mg/dl, serum Lp(a) levels decreased significantly after ACEI treatment, but the amount of proteinuria did not change in both subgroups. 5) In the analyses of subgroups of patients whose amounts of proteinuria definitively decreased (responder group) or increased (non-responder group) after ACEI, serum Lp(a) levels decreased even in the non-responder group.
CONCLUSION
NIDDM patients with overt proteinuria have higher level of serum Lp(a) than patients without overt proteinuria, and ACEI treatment could reduce serum Lp(a) level as well as proteinuria. Although decrease in Lp(a) is thought to be associated with decreased proteinuria, there may be another effect of ACEI that should be clarified further.