Meta‐analysis: Prevalence of significant or advanced fibrosis in adults with alpha‐1‐antitrypsin deficiency

Summary Background The prevalence of liver fibrosis detected by non‐invasive imaging in alpha‐1‐antitrypsin (AAT) deficiency has not been systematically assessed. Aims We conducted a systematic review and meta‐analysis to determine the prevalence of significant fibrosis and advanced fibrosis in AAT deficiency based on non‐invasive imaging. Methods Medline and Embase electronic databases were searched for studies from inception to 13 November 2022 that provided data for the prevalence of fibrosis in adults with AAT deficiency. A generalised linear mixed model with Clopper–Pearson intervals was used to pool single‐arm outcomes. Results Of the 214 records identified, 8 studies were included. Five studies assessed fibrosis using vibration‐controlled transient elastography. The prevalence of significant fibrosis (defined as ≥7.1 kPA) in Z homozygosity, Z heterozygosity and non‐carrier status was 22.10% (five studies, 95% CI: 17.07–28.12), 9.24% (three studies, 95% CI: 4.68–17.45) and 5.38% (one study, 95% CI: 3.27–8.73), respectively, p