Background Lipid profils in patients with rheumatoid arthritis.

Objectives To investigate lipid profiles in patients with active and inactive rheumatoid arthritis (RA) and to assess the relationship of the inflammatory condition of RA with lipid profiles.

Methods Seventy-two patients with RA and 25 age and sex matched healthy controls were studied. Patients with RA had not been treated with corticosteroid drugs prior to the study. Forty patients had active disease, and 32 had inactive disease. Plasma lipoproteins were fractionated by gradient ultracentrifugation into subfractions, and their chemical composition and mass were determined. Total cholesterol, triglyceride, LDL-cholesterol, HDL-cholesterol apolipoprotein AI (apo Al)/apolipoprotein B (apo B), lipoprotein (a) [Lp (a)], lipoprotein-associated platelet-activating factor acetylhydrolase (PAF-AH) activity and C-reactive protein (CRP) were measured in both groups.

Results Patients with active RA had significantly lower plasma total cholesterol and high-density lipoprotein (HDL) cholesterol (42.9 vs. 56.1 mg/dl) levels as compared with controls, due to the decrease in the mass of both the HDL2 and HDL3 subfractions. Patients with active RA also had higher plasma triglyceride levels, mainly due to the higher triglyceride content of the very low-density lipoprotein plus the intermediate-density lipoprotein subfraction. The plasma PAF-AH activity in patients with active RA was lower than that in controls, mainly due to the decrease in PAF-AH activity associated with the intermediate and dense low-density lipoprotein subclasses. The levels of apo Al and HDL-cholesterol were significantly lower in patients than in controls (121.4 vs. 147.4 mg/dl,). The level of Lp (a) was significantly higher in patients than in controls (29.2 vs. 19.2 mg/dl). The ratios of apo B/apo Al, total cholesterol/HDL-cholesterol, and LDL-cholesterol/HDL-cholesterol were significantly higher in patients than in controls (0.89 vs. 0.61, 4.6 vs. 3.2, 2.7 vs. 1.7, respectively). CRP showed a significant correlation with apo Al (r = -0.47, p < 0.05).

Conclusion This study suggests that patients with active RA have altered lipoprotein and apolipoprotein pattems that may possibly expose them to higher risk of atherosclerosis. The inflammatory condition of RA may affect the metabolism of HDL-cholesterol and apo A1. Our study to show that patients with active RA exhibit low levels of HDL2 and HDL3 and are deficient in plasma PAF-AH activity. These alterations suggest that active RA is associated with partial loss of the antiinflammatory activity of plasma Apo B- and Apo A-I-containing lipoproteins.