Clinical Outcomes and Inpatient Mortality Among Hospitalized Patients With Concomitant Autoimmune Hepatitis and Systemic Lupus Erythematosus

Background Autoimmune hepatitis (AIH) is an inflammatory disease of the liver that is characterized by a broad disease spectrum, circulating autoantibodies, and elevated serum globulin levels. Systemic lupus erythematosus (SLE) is a chronic disease that is characterized by a high inflammatory state and is associated with multiorgan system involvement. Despite a well-known association between AIH and other autoimmune diseases, the literature is deficient on the associations between AIH-related outcomes and complications in SLE patients. This study aims to evaluate the effects of SLE on clinical outcomes and inpatient mortality in patients with AIH. Method The National Inpatient Sample (NIS) database was used to identify AIH-related hospitalizations from 2012 to 2014 using International Classification of Diseases Ninth Edition Revision (ICD-9) codes. Patients were divided into two groups, those with and without SLE. Primary outcomes were mortality, hospital charges, and length of stay (LOS). Secondary outcomes were complications associated with AIH: cirrhosis, gastrointestinal (GI) bleed, acute liver failure (ALF), cholangitis, pancreatitis, and sepsis. Chi-squared tests for categorical data and independent t-test for continuous data were used to compare outcomes. Multivariate analysis was performed to assess the primary outcomes after adjusting for confounding variables. Results There were 17,050 AIH-related hospitalizations from 2012 to 2014 and 1,115 patients had SLE. In patients with SLE and AIH, 1,035 were female with average age of 48.6. The average LOS was 6.3 days, mortality rate was 1.35%, and total hospital charges were $48,146. SLE was associated with a statistically significant lower mortality rate compared to the control. LOS, hospital cost, and CCI (Charlson Comorbidity Index) were not found to be significantly different. For secondary outcomes, SLE was statistically significant for having higher pancreatitis rates. SLE patients had statistically significant lower cholangitis, and ALF. Differences in complications such as sepsis and GI bleed were non-significant. Conclusion SLE is known to have a high inflammatory state so it was hypothesized that there would be higher rates of complications and a higher mortality rate in those with concomitant AIH. This study showed that the mortality rate was lower in SLE patients with lower rates of complications including ALF and cholangitis. We postulate that SLE patient outcomes are likely affected by the treatment regimen involved with SLE, including corticosteroids. This would provide an immunosuppressive state, limiting the autoreactivity cascade in AIH, in effect leading to better outcomes and a mortality benefit. This study identifies a lower mortality rate and lower complication rates in patients with AIH and SLE overlap as compared to patients with AIH alone and future studies are needed to confirm these associations.