Dyslipoproteinaemia in patients with active, chronic polyarthritis. a study on serum lipoproteins and triglyceride clearance (intravenous fat tolerance test)

Abstract

<h2>Abstract</h2> Serum lipoproteins and the intravenous fat tolerance test were determined in 28 patients with active chronic polyarthritis, in most cases classical rheumatoid arthritis (RA). Two groups of RA patients were studied. One group was treated with only salicylates or other antiphlogistic drugs, the other also with steroids, cytostatics etc. The low concentration of total serum cholesterol, well known in RA, was found to result from low concentrations in all three lipoprotein fractions VLDL, LDL and HDL compared to randomly selected healthy male and female controls. A slight reduction of the total serum triglyceride (TG) concentration was observed, which corresponded to minor TG reductions in each lipoprotein class. As a consequence the LDL composition was altered containing more TG for each cholesterol value than controls. The cholesterol/TG ratio in VLDL in RA patients was higher than in controls. One possible explanation of these findings could be that in RA an accumulation of the intermediate density lipoprotein (IDL) occurred. The HDL cholesterol concentration in RA patients was very low compared to controls. When compared to the negative regression line which exists between VLDL-TG and HDL-cholesterol determined in controls, RA patients were found to have lower HDL-cholesterol than expected for any VLDL-TG concentration. The clinical implication of this finding may be of interest since it has been demonstrated that a low HDL-cholesterol concentration is associated with an increased risk for atherosclerotic manifestations. The lipoprotein data were similar in both RA groups independently of treatment. The fractional removal rate of intravenously injected exogenous TG (Intralipid) from the circulation was very high in RA patients compared to controls. This could be due to an increased flow past removal sites.