Liver disease epidemiology and burden in patients with alterations in plasma protein metabolism: German retrospective insurance claims analysis

BACKGROUND: Alpha-1 antitrypsin deficiency is a rare genetic disease and a leading cause of inherited alterations in plasma protein metabolism (APPM). AIM: To understand the prevalence, burden and progression of liver disease in patients with APPM including alpha-1 antitrypsin deficiency. METHODS: We conducted a retrospective analysis of anonymized patient-level claims data from a German health insurance provider (AOK PLUS). The APPM cohort comprised patients with APPM (identified using the German Modification of the International Classification of Diseases-10(th) Revision [ICD-10-GM] code E88.0 between 01/01/2010-30/09/2020) and incident liver disease (ICD-10-GM codes K74, K70.2-3 and K71.7 between 01/01/2012-30/09/2020). The control cohort comprised patients without APPM but with incident liver disease. Outcomes were incidence/prevalence of liver disease in patients with APPM, demographics/baseline characteristics, diagnostic procedures, progression-free survival (PFS), disease progression and mortality. RESULTS: Overall, 2680 and 26299 patients were included in the APPM (fibrosis, 96; cirrhosis, 2584) and control (fibrosis, 1444; cirrhosis, 24855) cohorts, respectively. Per 100000 individuals, annual incidence and prevalence of APPM and liver disease was 10-15 and 36-51, respectively. In the APPM cohort, median survival was 4.7 years [95% confidence interval (CI): 3.5-7.0] and 2.5 years (95%CI: 2.3-2.8) in patients with fibrosis and cirrhosis, respectively. A higher proportion of patients in the APPM cohort experienced disease progression (92.0%) compared with the control cohort (67.2%). Median PFS was shorter in the APPM cohort (0.9 years, 95%CI: 0.7-1.1) compared with the control cohort (3.7 years, 95%CI: 3.6-3.8; P < 0.001). Patients with cirrhosis in the control cohort had longer event-free survival for ascites, hepatic encephalopathy, hepatic failure and esophageal/gastric varices than patients with cirrhosis in the APPM cohort (P < 0.001). Patients with fibrosis in the control cohort had longer event-free survival for ascites, cirrhosis, hepatic failure and esophageal/gastric varices than patients with fibrosis in the APPM cohort (P < 0.001). In the APPM cohort, the most common diagnostic procedures within 12 mo after the first diagnosis of liver disease were imaging procedures (66.3%) and laboratory tests (51.0%). CONCLUSION: Among patients with liver disease, those with APPM experience substantial burden and earlier liver disease progression than patients without APPM.