Prediction of cardiovascular events in patients with ankylosing spondylitis and psoriatic arthritis: role of lipoproteins in a high-risk population.

Objective: To evaluate lipids and apolipoproteins as predictors of cardiovascular mortality and morbidity (CVD) in patients with spondyloarthritis (SpA).
Methods: In the pooled cohort of participants in the IDEAL, TNT, and CARDS trials, 50 had ankylosing spondylitis (AS), 36 had psoriatic arthritis (PsA), and 21,641 did not have AS or PsA (non-SpA). We compared lipid levels at baseline between AS or PsA and non-SpA, and hazard ratios (HR) for CVD were calculated in a Cox proportional hazard model.
Results: Atherogenic lipids were lower in samples from AS, but not in PsA, compared to non-SpA. The HR for 1 SD increase in baseline lipids for future CVD was for total cholesterol 1.39 (95% CI 0.82, 2.36) in AS, 1.01 (95% CI 0.44, 2.31) in PsA, and 1.10 (95% CI 1.07, 1.14) in non-SpA. Both high-density lipoprotein (HDL) and apolipoprotein (ApoA-1) were significantly associated with CVD in AS (HR 3.67, 95% CI 1.47, 9.06, and HR 1.89, 95% CI 1.02, 3.54, respectively), in contrast to PsA (HDL: HR 1.03, 95% CI 0.49, 2.15; ApoA-1: HR 0.79, 95% CI 0.34, 1.89) and non-SpA (HDL: HR 0.86, 95% CI 0.84, 0.89; ApoA-1: HR 0.88, 95% CI 0.85, 0.91).
Conclusion: HDL and ApoA-1 were surprisingly associated with increased risk of future CVD in patients with AS, whereas these lipids were protective in non-SpA.