Effects of Lipoprotein apheresis on the Lipoprotein(a) levels in the long run.

BACKGROUND: Lipoprotein(a) (Lp(a)) is a low density lipoprotein-like particle to which apolipoprotein(a) is bound. It is recognized as an atherosclerosis-inducing risk factor. Up to now a detailed description of the effect of Lipoprotein apheresis (LA) on Lp(a) levels in the long run is lacking.

METHODS: We studied 59 patients with elevated Lp(a) levels who were treated with LA at the Lipoprotein Apheresis Center at the University Hospital Dresden. We analyzed Lp(a) concentrations before the start of the LA treatment and during this extracorporeal therapy.

RESULTS: Comparing the Lp(a) levels before the start of LA therapy and pre-apheresis (measured before the LA sessions) Lp(a) levels, we observed a reduction of the Lp(a) levels of about 22.8% in all patients. Lp(a) levels were acutely (comparing post-apheresis with pre-apheresis concentrations) reduced by all 6 available LA methods (by about 70%). A linear regression analysis was performed to differentiate the long term course of pre-apheresis Lp(a) levels. In 30 patients we saw an increase of the pre-apheresis Lp(a) levels over the time, in 15 patients a constancy and in 14 patients a decrease. Patients with a decrease of pre-apheresis Lp(a) levels over the time had significantly higher initial (before the start of the extracorporeal treatment) and pre-apheresis values and they were significantly older. These patients had significantly more severe peripheral arterial disease as well as cardiac valve and carotid stenosis. The patients with the lowest initial Lp(a) levels and an increase of the pre-apheresis Lp(a) levels over the time had the highest percentage of intake of Tredaptive(®)/Niaspan(®) though after stopping the intake of these nicotinic acid preparations no clear increase of Lp(a) concentrations was observed. The applied LA systems did not seem to have a significant influence on the course of pre-apheresis Lp(a) levels. In all patients there was a high variability of Lp(a) concentrations between LA sessions which may in part be due to the inaccuracy of the method used to measure Lp(a) concentrations.

CONCLUSION: Pre-apheresis Lp(a) levels (before the LA sessions) are lower than those before the start of a LA treatment but they behave differently among patients during LA treatment.