Prevalence of Major Pulmonary Complications Among Patients with Systemic Lupus Erythematosus (SLE): A Systematic Review and Meta-Analysis.

OBJECTIVE: The prevalence of major pulmonary complications of systemic lupus erythematosus (SLE) such as interstitial lung disease (ILD), pulmonary arterial hypertension (PAH), diffuse alveolar hemorrhage (DAH), shrinking lung syndrome (SLS) and acute lupus pneumonitis (LP) has been less studied. METHODS: We searched PubMed and EMBASE for observational studies evaluating major pulmonary complications in individuals with SLE. We calculated the pooled prevalence of interstitial lung abnormalities (ILA/radiographic ILD) and clinical ILD, as well as PAH, DAH, SLS, LP among individuals with SLE with data available from eligible prospective and retrospective studies. We used 95% confidence intervals. Our study was registered on PROSPERO (CRD420251118717). RESULTS: From 1,347 abstracts, we identified 40 studies with relevant data. We estimated that the pooled prevalence of ILA was 12.39% (95% CI: 9.68-15.36%) while for PAH, LP, DAH and SLS they were 2.30% (95% CI: 1.84-2.81%), 3.05% (95% CI: 1.53-4.85%), 1.37% (95% CI: 0.70-2.22%), 1.25% (95% CI: 0.05-2.19%), respectively. Regarding clinical ILD, the pooled prevalence was 2.92% (95% CI: 1.50 - 4.46%). As for ILD radiographic patterns, the prevalence of non-specific interstitial pneumonia (NSIP) and usual interstitial pneumonia (UIP) was 52.47% (95% CI: 37.36 - 67.37%) and 12.09% (95% CI: 5.01 - 21.24%), respectively among SLE patients with ILD. DISCUSSION: Major pulmonary complications in SLE are more prevalent than previously recognized, especially radiographic findings of interstitial lung abnormalities. ILD with an NSIP pattern is the most common one while it is reassuring that DAH, SLS, LP remain relatively rare. Targeted screening with HRCT or right heart catheterization for ILD and PAH respectively along with timely intervention in high-risk or symptomatic patients could improve outcomes.