Reasons for hospitalization and in-hospital mortality for anti-neutrophil cytoplasmic antibody vasculitides: analysis of the National Inpatient Sample.

OBJECTIVE

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a heterogeneous group of conditions resulting in frequent hospitalizations and high in-hospital mortality (IHM). Our study aimed to use the National Inpatient Sample (NIS) to determine and categorize the main reasons for hospital admission and IHM in patients with AAV.

METHODS

We performed a retrospective study of adult AAV hospitalizations in 2016, 2017, and 2018 in acute care hospitals across the USA conducted using the NIS database. We classified the main reasons for hospital admission and IHM into 19 different categories using the principal International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10) diagnosis.

RESULTS

A total of 41,155 hospitalizations had either a principal or secondary ICD-10 code for AAV (GPA or MPA). Rheumatologic and respiratory diagnoses were the most common reasons for hospitalization, while infectious and respiratory diagnoses were the most common reasons for IHM. Sepsis, unspecified organism A41.9, was the most common specific principal diagnosis for hospitalized and deceased AAV patients.

CONCLUSIONS

Our results show that the leading reasons for hospitalization and mortality for AAV patients were rheumatologic, respiratory, and infectious diagnoses. This data suggests that careful monitoring and management of infectious and pulmonary complications in AAV may improve hospital outcomes. Key points • AAV is a heterogeneous group of conditions resulting in frequent hospitalizations and high IHM. In our study, AAV hospitalizations ended in IHM 4.5% of the time, substantially greater than non-ANCA patients. • The leading reasons for hospital admission for AAV patients were rheumatologic and respiratory diagnoses, but the main reason for IHM were infectious and respiratory diagnoses. • Sepsis was the most common principal diagnosis for hospitalized and deceased AAV patients. • Our results highlight the importance of close monitoring and timely management of infectious and respiratory complications to improve hospitalization outcomes.