Serious infections in people with systemic sclerosis: a national US study

OBJECTIVE: To study incidence, time trends, and outcomes of serious infections in systemic sclerosis (SSc). METHODS: We used the 1998–2016 US National Inpatient Sample data. We examined the epidemiology, time trends, and outcomes of five serious infections (opportunistic infections (OI), skin and soft tissue infections (SSTI), urinary tract infection (UTI), pneumonia, and sepsis/bacteremia) in hospitalized people with SSc. We performed multivariable-adjusted logistic regression analyses to analyze independent association of factors with healthcare utilization (hospital charges, length of hospital stay, discharge to non-home setting) and in-hospital mortality. RESULTS: There were 49,904,955 hospitalizations with serious infections in people without SSc and 61,615 in those with SSc. During 1998–2016, the most common serious infections in SSc were pneumonia (45%), sepsis (32%), SSTI (19%), UTI (3%), and OI (3%). In 2013–2014, sepsis surpassed pneumonia as the most common serious infection; by 2015–2016, sepsis was 1.8 times more common than pneumonia. Over the study period, hospital charges increased, while length of hospital stay and in-hospital mortality decreased, overall and for each serious infection. Multivariable-adjusted analyses showed that sepsis, age ≥ 80 years, and Deyo-Charlson score ≥ 2 were associated with significantly higher odds of healthcare utilization and in-hospital mortality, and Medicare or Medicaid insurance payer, Northeast location, urban teaching or non-teaching hospital, and medium or large hospital bed size with significantly higher odds of healthcare utilization. CONCLUSIONS: Outcomes in people with SSc hospitalized with serious infections have improved over time, except higher hospital charges. Identification of factors associated with higher healthcare utilization and in-hospital mortality allows for developing interventions to improve outcomes.