Comparison of Lp(a) Concentrations and Some Potential Effects in Hemodialysis, CAPD, Transplantation, and Control Groups, and Review of the Literature

Abstract

Apolipoprotein (a) – Lp(a) – is reported to be an independent risk factor for coronary artery disease and for hemodialysis (HD) access occlusion. Homology with plasminogen may predispose to thrombosis. High concentrations usually have been reported in patients on HD and on continuous ambulatory peritoneal dialysis (CAPD), but near-normal values in many kidney transplants (TP). We used Pharmacia immunoradiometric assay in 52 patients on HD, 58 on CAPD, 94 after TP, and 56 controls. The Lp(a) mean levels for CAPD, HD, TP, and control groups were 738, 647, 348, and 368 U/l and the medians were 542, 537, 96 and 143 U/l, respectively. The means and medians for CAPD and HD were significantly greater than those for TP and controls (p < 0.003 for means and < 0.005 for medians). We found no significant difference between: (1) Lp(a) means or medians comparing HD and CAPD or TP and controls; (2) Lp(a) means for the 33 patients with insulin-dependent diabetes mellitus and the 171 without; (3) number of occlusions of HD fïstulae or grafts in patients with high Lp(a) values and without; (4) mean Lp(a) for CAPD patients on gemfibrozil and also for TP patients on 3-hydroxy-methylglutaryl coenzyme 1 reductase inhibitors, or diet alone, before and after treatment, and (5) mean Lp(a) values for HD and CAPD patients with and without myocardial infarction. Lp(a) did not correlate significantly with fractional shortening or left ventricular end systolic or diastolic diameter by echocardiogram or with ejection fraction. For TP patients, Lp(a) and serum creatinine correlated (p = 0.004), and mean Lp(a) for 71 TP on ciclosporin A exceeded that for the other 23 patients (p < 0.03). Lp(a) fell in 13 of 14 patients after TP (mean fall 77%). The dominant Apo(a) isoform in 10 of 13 patients on CAPD or HD with high Lp(a) values was the equivalent of S2 (Utermann). Lp(a) in HD or CAPD is often elevated and regulated by both genetic and renal failure factors, but falls after TP with return of renal function and mainly genetic regulation. Lp(a) was not a risk factor for coronary artery disease in HD or CAPD patients and did not fall significantly with two drugs or diet.

Fluvastin therapy affects TAFI concentration in kidney transplant recipients

“…In our study, Lp(a) concentrations were not influenced by short-term fluvastatin therapy. It has been observed that both sinivastatin and lovastatin also did not alter Lp(a) levels in kidney allograft recipients [28].…”

Lipoprotein (a): impact by ethnicity and environmental and medical conditions

“…In contrast, mixed results regarding Lp(a) have been reported from cross sectional studies (163,169,174,185,(194)(195)(196)(197)(198)(199)(200)(201)(202)(203)(204). Notably, the decrease of Lp(a) in renal transplant patients was in dependent of the modality of immunosuppressive therapy (169,(184)(185)(186)(187)(188)(189)(190)(191), arguing against a contribution by an in flammatory component.…”

“…The influence of renal transplantation on Lp(a) con centrations has also been investigated and prospective studies generally demonstrate a decrease of Lp(a) levels following kidney transplantation (169,(184)(185)(186)(187)(188)(189)(190)(191)(192)(193), although the followup period has been limited. In contrast, mixed results regarding Lp(a) have been reported from cross sectional studies (163,169,174,185,(194)(195)(196)(197)(198)(199)(200)(201)(202)(203)(204).…”

“…A large number of studies have investigated Lp(a) in ESRD patients (145,(161)(162)(163)(164)(165)(166)(167)(168)(169)(170)(171), and elevated Lp(a) levels are seen both in patients undergoing hemodialysis (HD) or continuous ambulatory peritoneal dialysis (145,(161)(162)(163)(164)(165)(166)(167)(168)(169). Further, a mild glomerular filtration rate impair ment was associated with a higher Lp(a) level in a recent study of diabetic patients (172).…”

Serum Lp(a) Levels in Patients with Moderate Renal Failure

“…Even though predialysis patients exhibit high serum Lp(a) levels [5, 6], there are sparse data with regard to serum Lp(a) concentrations in patients with mild/moderate renal failure [7, 8]. …”