P3D258: Effects of the COVID-19 Period on Pediatric Inpatient and Outpatient Service Utilization for Gastroenteritis and Urinary Tract Infection in US Military Health Facilities

Background: COVID-19 pandemic policies coincided with rapid, national declines in all-cause pediatric inpatient admissions in the United States. Examining service utilization for acute conditions in both the inpatient and outpatient settings could help to tease out whether declines were partially related to shifts in care seeking location by families. The nationally-representative Military Health System (MHS) provides care to more than 1.5 million of the Nation’s children, and affords this opportunity. Our objective was to determine whether service utilization for acute gastroenteritis (GE) and urinary tract infection (UTI) declined across inpatient (INPT) and outpatient (OPT) settings in the MHS over the pandemic.

Methods: This retrospective, repeated monthly cross-sectional study used MHS billing data to describe trends in pediatric INPT and OPT visits for GE and UTI for children 0-17 years and any pandemic period effects [pre-pandemic (PP: Jan ‘18 - Feb ’20), early pandemic (EP: Mar - Dec ’20) and late pandemic (LP: Jan ‘21 - Apr ’22)]. Outcomes were primary diagnosis of GE or primary diagnosis of dehydration with a secondary diagnosis of GE, and primary diagnosis of UTI, calculated as visits per 1,000 population in INPT and OPT settings. Sociodemographic factors of interest were sex, age, sponsor rank, and geographic region. We calculated unadjusted and adjusted rate ratios for GE and UTI using Poisson regression.

Results: Rates of GE visits in INPT and OPT settings declined suddenly in the EP and have subsequently returned to PP levels (Fig 1a-b). Adjusted GE rate declines were similar for INPT and OPT (Table 1). The rate of GE visits declined in INPT and OPT settings with higher sponsor rank. Throughout the pandemic, rates of UTI INPT visits were generally lower than PP, although not substantially so (Fig 1c). In the OPT setting, a marked difference in the rate of UTI visits occurred and persisted throughout the pandemic (Fig 1d). The rate of INPT visits was most reduced in the LP, whereas there was little difference between EP or LP in the OPT setting (Table 1).

Conclusion: Gastroenteritis INPT and OPT rates in the EP and LP periods may reflect policies around in-person school closures with relaxed policies later in the pandemic, as well as improved OPT service utilization and better care quality generally. Persistent reductions over time in UTI service utilization rates may reflect reduced need for services due to age-specific behavioral changes indirectly related to pandemic policies. These might include reduced withholding in daycare- and school-aged children at home, and less frequent sexual intercourse in teens.