Plasma apolipoproteins and risk for age related maculopathy

To determine if elevated plasma levels of atherogenic and/or anti-atherogenic lipoproteins are risk factors for developing age related maculopathy (ARM).

In a cross sectional study in a university clinic setting, 129 patients (72 women and 57 men) underwent colour fundus photography, acuity and contrast sensitivity assessment, and electroimmunoassays of plasma apolipoproteins B (apoB) and A-I (apoA-I), the principal proteins of low density and high density lipoproteins, respectively. Maculopathy stage was assigned using the AREDS grading system.

Levels of apoB in no ARM, mild, intermediate, and advanced ARM groups were 93.3, 91.8, 95.2, and 98.2 mg/dl, respectively. Levels of apoA-I were 147.4, 148.6, 141.0, and 144.9 mg/dl in the same groups. There was no significant association between these measures, typical for age, and maculopathy stage.

Although drusen associated with ARM and ageing contain cholesterol and apoB, like the lipid rich core of an atherosclerotic plaque, the results of this study and our previous work in toto make the prospects of a plasma origin for these lesion constituents increasingly untenable. This conclusion is consistent with an emerging hypothesis that a large lipoprotein of intraocular origin is an important pathway for constituent retinal lipid processing and the biogenesis of drusen.