Latest COVID-19 research looks at obesity, AKI, nursing home prescribing, symptom checkers

Recent studies looked at conditions that worsen COVID-19 and vice versa. Higher body mass index (BMI) was common among COVID-19 patients and associated with worse outcomes, according to a study published by MMWR on March 8. Of 148,494 U.S. patients admitted or treated in EDs, 28.3% were overweight and 50.8% were obese. Both conditions were associated with risk of mechanical ventilation, and obesity was a risk factor for hospitalization and death. “The findings in this report highlight a dose-response relationship between higher BMI and severe COVID-19–associated illness and underscore the need for progressively intensive illness management as obesity severity increases,” the authors said.

Acute kidney injury (AKI) may be worse when associated with COVID-19, according to a study published by JAMA Network Open on March 10. It compared 182 patients with AKI after COVID-19 to 1,430 patients with AKI not from COVID-19 and found that the former had greater decreases in estimated glomerular filtration rate after discharge, which “may reinforce the importance of monitoring kidney function after AKI and studying interventions to limit kidney disease after COVID-19–associated AKI,” the authors said.

Two studies highlighted worrisome prescribing practices in nursing homes during the pandemic. An analysis of pharmacy data from 1,944 U.S. nursing homes, published by Clinical Infectious Diseases on March 10, found high use of hydroxychloroquine and azithromycin in April 2020 (increases of 563% and 150% compared to 2019, respectively). The rates decreased in May after FDA warnings but remained elevated relative to 2019 rates through October. Psychotropic drug prescribing also increased, according to a study of nursing homes in Ontario, Canada, published as a research letter March 15 by JAMA Internal Medicine. The percentage of residents who received prescriptions for antipsychotic medications, antidepressant medications, and trazodone was higher from March through September 2020 compared with January to February 2020. The authors speculated that prescribers may have been treating “consequences of prolonged social isolation produced by infection prevention and control measures” and “less likely to prioritize favorable nonpharmacological management for common issues, such as responsive behaviors, because of diminished resources, including lack of staffing.”

Another study, published by BMJ Health & Care Informatics on March 8, tested online symptom checkers from Singapore, Japan, the U.S., and the U.K. using 52 simulated cases of COVID-19 or mimics (e.g., sepsis, bacterial pneumonia). The U.S. tool (the CDC Coronavirus Symptom Checker) triaged 38% of cases to health care contact and consistently failed to identify severe COVID-19 or bacterial pneumonia and sepsis, triaging patients with symptoms of these conditions to stay home. The authors concluded that “there is the potential for such patient-led assessment tools to worsen outcomes by delaying appropriate clinical assessment.”

Good news came from recent vaccine research. Vaccinated patients were less likely to test positive for SARS-CoV-2 before a procedure, according to a study published by Clinical Infectious Diseases on March 10. Positive results were found in 42 (1.4%) of 3,006 tests performed on asymptomatic patients who had received at least one COVID-19 vaccine dose compared to 1,436 (3.2%) of 45,327 tests performed on unvaccinated patients (relative risk, 0.44; 95% CI, 0.33 to 0.60; P<0.0001). The effect was even greater (an 80% reduction) among the subgroup of patients who had received two doses. “These results are consistent with previously published data showing a reduction in asymptomatic infection following vaccination with an mRNA vaccine, even after one dose,” the authors said.

Two studies found high antibody responses after a single shot of an mRNA vaccine among people who had already had COVID-19. A letter published by the New England Journal of Medicine on March 10 compared 67 vaccine recipients with negative serology tests for SARS-CoV-2 to 43 with positive serology. The majority of the former group had relatively low IgG responses nine to 12 days after vaccination, while those in the latter “rapidly developed uniform, high antibody titers within days after vaccination,” the authors said. The study also looked at side effects from vaccination and found that seropositive patients more commonly reported them after the first dose (89% vs. 46%). A similar study, published by JAMA on March 1, included 59 vaccinated health care workers (17 with negative serology, 16 positive but asymptomatic, and 26 who had been symptomatic) and found higher antibody titer responses to a single dose of mRNA vaccine in those who were previously infected, starting to peak at seven days.