EARLY ELEVATION OF LIPOPROTEIN(A) LEVELS IN CHRONIC RENAL-INSUFFICIENCY

Serum lipoprotein(a) [Lp(a)] concentrations in chronic renal failure p atients were investigated in relation to the degree of renal insuffici ency, treatment by maintenance hemodialysis, and correction of uremia by renal transplantation with or without cyclosporin immunosuppression . Fast serum levels of Lp(a) (mg/100 mt) were determined in 34 chronic renal failure patients not in need of maintenance dialysis (16 with s erum creatinine 2.0-4.0 mg/100 mt; 18 with serum creatinine higher tha n 4.0 mg/100 mt), 40 patients treated by hemodialysis, 55 successful r enal transplant recipients (28 under cyclosporin treatment and 27 rece iving no cyclosporin), and 34 healthy controls. Age and sex distributi ons were similar among groups. Pregnant women; non-White individuals; subjects with obesity, diabetes, nephrotic syndrome, and hepatic and t hyroid diseases; and those treated with oral contraceptives or lipid-l owering drugs were excluded from the study. Compared to controls, medi an Lp(a) was increased in nondialyzed renal failure patients (II vs. 4 7.5 p < 0.001) and this was the only lipid abnormality observed in the group. There was no significant difference in Lp(a) levels between no ndialized renal failure patients with serum creatinine 2.0-4.0 and >4. 0 mg/100 mt (47 vs. 49, NS). Moreover, Pearson correlation coeficient (r = 0.01, NS) showed that Lp(a) values were not related to serum crea tinine in nondialyzed patients. In hemodialysis subjects Lp(a) concent rations (median = 29) were intermediate between those observed in nond ialyzed patients and controls but the differences were not significant Lp(a) levels in renal transplant patients treated with cyclosporin (m edian = 6) and not receiving cyclosporin (median = 13) were similar an d did not differ from controls. Serum Lp(a) increases and attains maxi mum levels with mild/moderate reduction in renal function, and does no t seem to change through late renal failure stages or in relation to t he introduction of maintenance hemodialysis treatment. Correction of u remia by successful renal transplant caused normalization of Lp(a) lev els regardless of the use of cyclosporin. Increased Lp(a) levels may b e the earliest and more consistent lipid alteration seen in predialysi s renal failure.