Nursing home operators and community health officials may have a powerful new weapon for protecting residents in the near term, and against public healthcare emergencies.
A massive new study reveals nuances of COVID-19 infection and death flows in nursing homes.
Researchers found that who contracted COVID-19 was driven largely by factors in the building and surrounding community. But when it came to hospitalizations and deaths, patient characteristics such as age and body mass index mattered more.
A team from Johns Hopkins Bloomberg School of Public Health examined Medicare data for more than 480,000 long-stay residents at 15,038 nursing homes between April and September 2020 to determine which factors dictated COVID infection and death rates. They reported the results Wednesday in JAMA Network Open.
Among 137,119 residents — 28.4% — diagnosed with COVID-19 during the study period, researchers found risk of infection was dependent mainly on which nursing home the resident lived in, and in which county, rather than on patient-specific factors.
“Our findings suggest that the dynamics of the pandemic work differently in a nursing home setting than they do in the wider community,” said lead author Hemalkumar Mehta, Ph.D., assistant professor of epidemiology at Johns Hopkins.”The findings should help community leaders and nursing home administrators in devising better protections for nursing home residents during the remainder of the COVID-19 pandemic and in future pandemics.”
Among personal characteristics examined, body mass index alone appeared to be important in determining infection risk: Having a BMI greater than 45, considered morbidly obese, was associated with 19% more infection risk than having a BMI in the 18.5 to 25 range.
Hospitalization risk, however, varied more with personal factors. A BMI of 40 to 45 was associated with 24% greater risk, and BMI over 45 increased risk by 40%.
But it wasn’t just overweight patients most vulnerable to the virus. Those with a below-normal BMI also had a 19% greater risk of dying of COVID-19.
Frailty appeared to be a factor too. Residents with severe functional impairment were 15% more likely to be hospitalized after a COVID-19 infection; and catheter use increased the odds of hospitalization by 21%.
Residents with severe cognitive impairment were also 79% more likely to die of COVID-19 than those with no cognitive impairment, a finding that bolsters previous studies highlighting extreme risk among dementia patients.
Who was hospitalized and why?
Hospitalization and mortality risks typically align among people living at home, but they were disconnected in the nursing home setting during the pandemic.
In the case of flu and other illnesses, the risks of hospitalization and the risks of death associated with increasing age tend to parallel each other. Decisions for hospitalization of nursing home patients are influenced by clinical judgment on risk of death, which may have played an outsized role during COVID-19. There could have been a “lack of appropriate clinical evaluation and prognostication in facilities overwhelmed by the pandemic,” the researchers hypothesized.
The divergence also might “represent resident or family preference to avoid hospitalization, triaging decisions when local hospitals were full, or other factors yet to be determined,” Mehta said.
Despite trends that put minority populations at higher risk of COVID-19 infection across the U.S., within long-term care, the study found only “nominal differences” in infection rates between whites and Blacks, whites and Asians, and whites and Latinos in nursing homes.
Asians in long-term care were, however, 19% more likely than whites to die when they got COVID-19.
Age was the largest apparent mortality risk factor. For example, being over 90 was associated with 155% greater risk of death, compared to being 65 to 70.