Association of Rural Residence with Short-Term Mortality in Critically Ill Patients with Covid-19

ABSTRACT

INTRODUCTION: Rural residence has been associated with increased risk of COVID-19-related mortality. However, the population-level prognostic implications of rural residence among critically ill patients with COVID-19 are lacking, and the impact of inter-hospital transfer and hospitals' location on the outcomes of these patients is unknown. METHOD(S) We used a statewide dataset to identify ICU admissions aged >=18 years with a diagnosis of COVID-19 in Texas during April 1-December 31, 2020. COVID-19 was defined by ICD-10 code U07.1. We used dichotomized (rural vs urban) ZIP Code-level Rural-Urban Commuting Area categories, linked to hospitalization data, to identify rural residence. Hierarchical, mixed-effects models were fit to estimate the association of rural residence with shortterm mortality (defined as in-hospital death or discharge to hospice) for the whole cohort and among hospitalizations with and without transfer from another hospital. Similar modeling was used to examine the association of care in rural hospitals among rural residents without transfer to another facility with short-term mortality. RESULT(S) Among 58,485 ICU admissions with COVID-19, 9,495 (16.2%) were rural residents. Among rural residents, 8,607 (90.6%) were managed in non-rural hospitals, and 1,827 (19.2%) were transferred from another hospital. The unadjusted short-term mortality among rural and urban residents was 25.9% vs 23.9%, respectively. Following adjustment for confounders, rural residence was associated with higher short-term mortality for the whole cohort (adjusted odds ratio [aOR] 1.093 [95% CI 1.003-1.191]) and among those transferred from another hospital (aOR 1.349 [95% CI 1.106-1.646]), but not among those without inter-hospital transfer (aOR 1.052 [95% CI 0.955-1.159]). Management of critically ill rural residents with COVID-19 in rural hospitals, without inter-hospital transfers was not associated with shortterm mortality on adjusted analyses (aOR 0.672 [95% CI 0.393-1.149]). CONCLUSION(S) The observed increased short-term mortality among critically ill patients with COVID-19 residing in rural areas is confounded by inter-hospital transfers and the geographic location of hospitals, with no adverse prognostic impact of rural residence in non-transferred patients and those managed in rural facilities.