Patients with rheumatoid arthritis (RA) have increased mortality and morbidity due to cardiovascular disease (CVD). A high apolipoprotein (apo)B/apoA1 ratio is known to predict cardiovascular events (CVEs) in the population. apoA1 has, besides anti-atherogenic effects, anti-inflammatory properties. The importance of apolipoproteins in the development of CVEs, in the context of lipids, haemostatic factors, and inflammation, was evaluated over 18 years in patients with RA.
Seventy-four patients with inflammatory active RA (61 females/13 males, mean age 63.6 years, disease duration 22.1 years) had been previously investigated in a study of haemostatic factors [tissue plasminogen activator (tPA), plasminogen activator inhibitor (PAI)-1, von Willebrand factor (vWF)], lipids (cholesterol and triglycerides), apolipoproteins (apoA1 and apoB), lipoprotein(a) [Lp(a)], and markers of inflammation [erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and haptoglobin]. After 18 years, the first CVE during follow-up and the presence of traditional CV risk factors, extra-articular disease, and pharmacological treatment were registered. Cox proportional hazards regression was used to identify predictors of a new CVE.
A new CVE (n = 34) was predicted by the apoB/apoA1 ratio (p < 0.01), the triglyceride level (p < 0.01), PAI-1 (p < 0.01) and tPA (p < 0.01) activities, vWF (p < 0.001), ESR (< 0.001), CRP (< 0.05), and haptoglobin (p < 0.05). apoA1 (p = 0.056) and apoB (p < 0.05) correlated weakly and inversely with haptoglobin and CRP, respectively. In a multiple Cox regression model, adjusted for gender and previous CVD, the apoB/apoA1 ratio significantly predicted a new CVE, as did vWF, PAI-1, and ESR.
The apoB/apoA1 ratio was a good predictor of CVE during 18 years of follow-up in patients with active RA. Apolipoproteins correlated negatively with inflammation.