Impact of SARS-CoV-2 Vaccine Rollout on Hispanic and Non-Hispanic Admission and Mortality Trends: An Interrupted Time Series Analysis

Abstract

Challenges with SARS-CoV-2 vaccine prioritization, access, hesitancy influenced vaccination uptake RESEARCH QUESTION: Was the impact of SARS-CoV-2 vaccine rollout on COVID-19 monthly admission and mortality trends different between Hispanic and non-Hispanic populations? We used Interrupted Time Series analysis to conduct an ancillary study of the VIRUS (Viral Infection and Respiratory illness Universal Study) registry supplemented by electronic health record data from 5 participating Mayo Clinic sites in Florida, Arizona, Minnesota Wisconsin states. We included hospitalized patients with COVID-19 admitted between April 2020 and December 2021. Our primary outcome was the impact of vaccine rollout on admission trends. Our secondary outcome was the impact of vaccine rollout on mortality trends. This interrupted time series analysis includes 6442 patients. Vaccine rollout was associated with improved monthly hospital admission trends among both Hispanic and non-Hispanic patients. Among Hispanic patients, pre-vaccine rollout, monthly admissions were increasing by 12.9%, [95% CI 8.1,17.9%]. Immediately following vaccine rollout, patient admissions declined by -66.3%, [95% CI -75.6, -53.9]. Post vaccine rollout, monthly admissions were increasing by 3.7%, [95% CI 0.2,7.3%]. Among non-Hispanic patients, pre-vaccine rollout, monthly admissions were increasing by 35.8% [95% CI 33.4,38.1%]. Immediately following vaccine rollout, patient admissions declined by -75.2% [95% CI -77.6, -72.7%]. Post-vaccine rollout, monthly admissions were increasing by 5.6%, [95% CI 4.5-6.7%]. These pre-vaccine rollout admission trends were significantly different (p<0.001) and post-vaccine rollout the change in admission trend was significantly different (p<0.001). The associated beneficial impact from vaccine rollout on monthly hospital admission trends among Hispanic patients was significantly lower. The trend in monthly mortality rate was four-fold greater (worse) 8.3% [95% CI 3.6,13.4%] among Hispanic patients versus 2.2% [95% CI 0.6,3.8%] among non-Hispanic patients but this was not related to vaccine rollout. SARS-CoV-2 vaccine rollout was associated with improved COVID-19 admission trends among non-Hispanic versus Hispanic patients. Vaccine rollout did not influence mortality trends in either group, which were four times higher among Hispanic patients. Improved vaccine rollout may have reduced disparities in admission trends for Hispanic patients, but other factors influenced their mortality trends.