Background Systemic lupus erythematosus (SLE) is associated with an increased cardiovascular (CV) burden. Different techniques have proven to be useful in determining the presence of subclinical CV disease, including endothelial dysfunction and atherosclerosis, and therefore to predict future vascular events.
Objectives To determine if subclinical atherosclerosis is increased in patients with SLE compared to healthy individuals, then to compare the relevance of each technique between studies.
Methods We performed a systematic search of studies published in PubMed up to June 2014, and reviewed recently-published abstracts from EULAR and ACR. Two reviewers independently screened articles, with a prespecified search strategy, to identify studies comparing rates of atherosclerosis in SLE patients versus healthy controls, using one of the following techniques: carotid intima-media thickness (CIMT), carotid plaque presence (CP) and flow-mediated dilatation (FMD). The results were pooled in a meta-analysis. Patient demographics, cardiovascular risk factors and treatments were collected.
Results Out of 136 articles initially identified, 49 were selected for the systematic review. Meta-analysis included 31 CIMT, 26 CP and 15 FMD studies. Compared to healthy controls, SLE patients had a significantly increased CIMT (mean difference (MD) 0.07mm CI95% [0.05 - 0.09]), p<0.05), more CP (OR 1.88 [1.52 - 2.32], p<0.05) and a decreased FMD (MD -4.01% CI95% [-5.81 - -2.22], p<0.05). We conducted a subgroup analysis regarding history of cardiovascular disease, which showed that in SLE patients without cardiovascular history, CIMT was still significantly increased (MD 0.06mm CI95% [0.03 - 0.09], p<0.05) and FMD still decreased (MD -3.22% CI95% [-5.06 - -1.38], p<0.05). There was marked heterogeneity between the studies, mainly explained by variable disease duration or organ damage in SLE, and differences in CV risk measure techniques. However, meta-analysis including only CIMT following new international recommendations showed still an increased CIMT in SLE patients but with low heterogeneity (MD 0.03mm CI95% [0.00-0.05], p<0.05, I2=0%).
Conclusions Patients with SLE are characterized by an increased subclinical atherosclerosis compared to healthy controls. CIMT seems to be a promising measure for CV risk evaluation, being non invasive, non radiant, and reproducible, and may be proposed as an alternative to the reliable carotid plaque evaluation and to FMD which is influenced by independent factors such as smoking. Future studies should focus on reducing the heterogeneity of these measures by using standardized procedures.
Disclosure of Interest None declared