Antiphospholipid antibodies can identify lupus patients at risk of pulmonary hypertension: A systematic review and meta-analysis.

Background: Pulmonary hypertension (PH) is a life-threatening condition that may affect outcomes in patients with systemic lupus erythematosus (SLE). The role of antiphospholipid antibodies (aPL) on the risk of PH is controversial. Therefore our objective was to estimate the risk of PH (WHO groups 1-5) including associated pulmonary arterial hypertension (APAH, WHO group 1 only) related to aPL in patients with SLE.

Methods: Systematic review and meta-analysis were performed: MEDLINE, EMBASE, Cochrane Library, congress abstracts, and reference lists of eligible studies were searched through 2015. Studies were selected if they included SLE patients with descriptions of the exposure to aPL and the outcomes (PH including APAH). Two reviewers extracted study characteristics and outcome data from published reports. Estimates were pooled using random effects models and sensitivity analyses. PROSPERO registration number: CRD42015016872.

Results: Of 984 identified abstracts, 31 primary studies (five cohorts, 13 case-control, 13 cross-sectional) met inclusion criteria, including 4480 SLE patients. Prevalence of PH in aPL-positive vs. aPL-negative SLE patients was 12.3% vs. 7.3%, respectively. The overall pooled odds ratio (OR) for PH was 2.28 (95% CI, 1.65 to 3.15) (I=39%). The risk of APAH was also significantly increased (OR=2.62 [95% CI, 1.11-6.15]). The risk of PH was the highest for lupus anticoagulant (OR=1.96 [95% CI, 1.31-2.92]) and IgG anticardiolipin antibodies (OR=2.64 [95% CI, 1.30-5.36]) while other antibodies were not significantly associated with PH.

Conclusions: Among SLE patients, aPL can identify patients at risk for PH and APAH. These findings warrant implementation of effective screening and early treatment strategies.