Evaluating COVID-19 vaccine effectiveness during pre-Delta, Delta and Omicron dominant periods among pregnant people in the U.S.: Retrospective cohort analysis from a nationally sampled cohort in National COVID Collaborative Cohort (N3C).

Objectives: To evaluate the effectiveness of COVID-19 vaccinations (initial and booster) during pre-Delta, Delta, and Omicron dominant periods among pregnant people via (1) COVID-19 incident and severe infections among pregnant people who were vaccinated vs. unvaccinated and (2) post-COVID-19 vaccination breakthrough infections and severe infections among vaccinated females who were pregnant vs. non-pregnant. Design: Retrospective cohort study using nationally sampled electronic health records data from the National COVID Cohort Collaborative (N3C), December 10, 2020, to June 07, 2022. Participants: Cohort 1 included pregnant people (15-55 years), and Cohort 2 included vaccinated females of reproductive age (15-55 years). Exposures: (1) COVID-19 vaccination and (2) pregnancy. Main outcome measures: Adjusted hazard ratios (aHRs) for COVID-19 incident or breakthrough infections and severe infections (i.e., COVID-19 infections with related hospitalizations). Results: In Cohort 1, 301,107 pregnant people were included. Compared to unvaccinated pregnant people, the aHRs for pregnant people with initial vaccinations during pregnancy of incident COVID-19 were 0.77 (95% CI: 0.62, 0.96) and 0.88 (95%CI: 0.73, 1.07) and aHRs of severe COVID-19 infections were 0.65 (95% CI: 0.47, 0.90) and 0.79 (95% CI: 0.51, 1.21) during the Delta and Omicron periods, respectively. Compared to pregnant people with full initial vaccinations, the aHR of incident COVID-19 for pregnant people with booster vaccinations was 0.64 (95% CI: 0.58, 0.71) during the Omicron period. In Cohort 2, 934,337 vaccinated people were included. Compared to vaccinated non-pregnant females, the aHRs of severe COVID-19 infections for people with initial vaccinations during pregnancy was 2.71 (95% CI: 1.31, 5.60) during the Omicron periods. Conclusions: Pregnant people with initial and booster vaccinations during pregnancy had a lower risk of incident and severe COVID-19 infections compared to unvaccinated pregnant people across the pandemic stages. However, vaccinated pregnant people still had a higher risk of severe infections compared to non-pregnant females.

Risk factors for severe outcomes of coronavirus disease 2019 through the waves of the pandemic: Comparing patients with and without solid organ transplantation.

BACKGROUND: While coronavirus disease 2019 (COVID-19) is no longer a public health emergency, certain patients remain at risk of severe outcomes. To better understand changing risk profiles, we studied the risk factors for patients with and without solid organ transplantation (SOT) through the various waves of the pandemic. METHODS: Using the National COVID Cohort Collaborative we studied a cohort of adult patients testing positive for COVID-19 between January 1, 2020, and May 2, 2022. We separated the data into waves of COVID-19 as defined by the Centers for Disease Control. In our primary outcome, we used multivariable survival analysis to look at various risk factors for hospitalization in those with and without SOT. RESULTS: A total of 3,570,032 patients were captured. We found an overall risk attenuation of adverse COVID-19-associated outcomes over time. In both non-SOT and SOT populations, diabetes, chronic kidney disease, and congestive heart failure were risk factors for hospitalization. For SOT specifically, longer time periods between transplant and COVID-19 were protective and age was a risk factor. Notably, asthma was not a risk factor for major adverse renal cardiovascular events, hospitalization, or mortality in either group. CONCLUSIONS: Our study provides a longitudinal view of the risks associated with adverse COVID-related outcomes amongst SOT and non-SOT patients, and how these risk factors evolved over time. Our work will help inform providers and policymakers to better target high-risk patients.

In-Person and Telehealth Provider Access and Glycemic Control for People With Diabetes During the COVID-19 Pandemic.

BACKGROUND: Ambulatory care underwent rapid changes at the onset of the COVID-19 pandemic. Care for people with diabetes shifted from an almost exclusively in-person model to a hybrid model consisting of in-person visits, telehealth visits, phone calls, and asynchronous messaging. METHODS: We analyzed data for all patients with diabetes and established with a provider at a large academic medical center to identify in-person and telehealth ambulatory provider visits over two periods of time (a "pre-COVID" and "COVID" period). RESULTS: While the number of people with diabetes and any ambulatory provider visit decreased during the COVID period, telehealth saw massive growth. Per Hemoglobin A1c, glycemic control remained stable from the pre-COVID to COVID time periods. CONCLUSIONS: Findings support continued use of telehealth, and we anticipate hybrid models of care will be utilized for people with diabetes beyond the pandemic.