Objectives The COVID-19 pandemic presents an urgent need to investigate whether existing drugs can enhance or even worsen prognosis; metformin, a known mammalian target of rapamycin (m-TOR) inhibitor, has been identified as a potential agent. We sought to evaluate mortality benefit among older persons infected with SARS-CoV-2 who were taking metformin as compared to those who were not. Design Retrospective cohort study Setting and Participants: 775 nursing home residents infected with SARS-CoV-2 who resided in one of the 134 Community Living Centers (CLC) of the Veterans Health Administration (VHA) during March 1, 2020 to May 13, 2020 were included. Methods Using a window of 14 days prior to SARS-CoV-2 testing, bar coded medication administration records were examined for dispensing of medications for diabetes. The COVID-19 infected residents were divided into groups: 1) residents administered metformin alone or in combination with other medications, 2) residents who used long acting or daily insulin, 3) residents administered other diabetes medications, and 4) residents not administered diabetes medication, including non-diabetics and untreated diabetics. Proportional hazard models adjusted for demographics, hemoglobin A1c, body mass index, and renal function. Results Relative to those not receiving diabetes medications, residents taking metformin were at significantly reduced hazard of death (adjusted HR 0.48, 95%CI 0.28, 0.84) over the subsequent 30 days from COVID-19 diagnosis. There was no association with insulin (adjusted HR 0.99, 95% 0.60, 1.64) or other diabetes medications (adjusted HR 0.71, 95% CI 0.38, 1.32). Conclusions and Implications Our data suggests a reduction in 30-day mortality following SARS-CoV-2 infection in residents who were on metformin-containing diabetes regimens. These findings suggest a relative survival benefit in nursing home residents on metformin, potentially through its mTOR inhibition effects. A prospective study should investigate the therapeutic benefits of metformin among persons with COVID-19.

Introduction. Acinetobacter baumannii is a top-priority pathogen of the World Health Organization (WHO) and the Centers for Disease Control (CDC) due to antibiotic resistance. Gap Statement. Trends in A. baumannii resistance rates that include community isolates are unknown. Aim. Identify trends in A. baumannii resistance rates across the Veterans Affairs (VA) Healthcare System, including isolates from patients treated in hospitals, long-term care facilities and outpatient clinics nationally. Methodology. We included A. baumannii clinical cultures collected from VA patients from 2010 to 2018. Cultures were categorized by location: VA medical centers (VAMCs), long-term care (LTC) units [community living centers (CLCs)], or outpatient. We assessed carbapenem resistance, multidrug resistance (MDR) and extensive drug resistance (XDR). Time trends were assessed with Joinpoint regression. Results. We identified 19 376 A . baumannii cultures (53% VAMCs, 4% CLCs, 43% outpatient). Respiratory cultures were the most common source of carbapenem-resistant (43 %), multidrug-resistant (49 %) and extensively drug-resistant (21 %) isolates. Over the study period, the number of A. baumannii cultures decreased significantly in VAMCs (11.9% per year). In 2018, carbapenem resistance was seen in 28% of VAMC isolates and 36% of CLC isolates, but only 6% of outpatient isolates, while MDR was found in 31% of VAMC isolates and 36% of CLC isolates, but only 8 % of outpatient isolates. Carbapenem-resistant, multidrug-resistant and extensively drug-resistant A. baumannii isolates decreased significantly in VAMCs and outpatient clinics over time (VAMCs: by 4.9, 7.2 and 6.9%; outpatient: by 11.3, 10.5 and 10.2% per year). Resistant phenotypes remained stable in CLCs. Conclusion. In the VA nationally, the prevalence of A. baumannii is decreasing, as is resistance. Carbapenem-resistant and multidrug-resistant A. baumannii remain common in VAMCs and CLCs. The focus of infection control and antimicrobial stewardship efforts to prevent transmission of resistant A. baumannii should be in hospital and LTC settings.