David Curtis Alexander, age 89, visits his wife Sheila, who has dementia. It's the first time he's been able to enter her room since October.
CNN  — 

As covid-19 resurges across the country, driven by the highly infectious delta variant, experts are extending our understanding of the pandemic’s toll on older adults — the age group hit hardest by the pandemic.

New research offers unexpected insights. Older adults living in their own homes and apartments had a significantly heightened risk of dying from covid last year — more than previously understood, it shows. Though deaths in nursing homes received enormous attention, far more older adults who perished from covid lived outside of institutions.

The research addresses essential questions: Which conditions appear to put seniors at the highest risk of dying from covid? How many seniors in the community and in long-term care institutions might have died without the pandemic? And how many “excess deaths” in the older population can be attributed to covid?

Of course, it’s already known that older adults suffered disproportionately. As of Aug. 4, more than 480,000 people age 65 and older perished from Covid-19 — 79% of more than 606,000 deaths in the U.S. overall, according to the latest data from the US Centers for Disease Control and Prevention. (This is likely an undercount because it relies on death certificate data that may not be up-to-date or accurately reflect the true toll of the virus.)

Still, new information about older adults’ vulnerabilities is useful as covid cases climb again and unvaccinated people remain at risk. Some key results from studies published over the past few months:

Death rates varied among groups of seniors. In a study published in Health Affairs in June, experts from the Department of Health and Human Services analyzed data for more than 28 million people with traditional Medicare coverage from February 2020 (the approximate start of the pandemic) to September 2020. (Excluded were about 24 million people in Medicare Advantage plans because data crucial to the study wasn’t available.) The researchers compared data for this period with previous years, dating to 2015.

The study examines deaths among individuals with covid and reaffirms headlines that have trumpeted the toll among older Americans. Medicare members diagnosed with covid had a death rate of 17.5% — more than six times the death rate of 2.9% for Medicare members who evaded the virus.

A notable finding in the study: Medicare members with dementia were especially vulnerable. If diagnosed with covid, their death rate was 32%, compared with nearly 14% for those with dementia who weren’t infected. Also at substantially increased risk of death from covid were older adults with serious and chronic kidney disease, immune deficiencies, severe neurological conditions and multiple medical conditions.

Most of the seniors who died of covid lived outside of nursing homes. The HHS experts’ study reported 110,990 “excess deaths” due to covid during the eight-month period it examined — most likely an undercount because many older adults who died may not have been tested or treated for the virus. The term “excess deaths” refers to a death count higher than the number expected based on historical data. It is a core measure of the pandemic’s impact.

Of the excess deaths HHS experts documented, 40% occurred in nursing homes but a larger portion, nearly 60%, were seniors living in other settings.

Other studies suggest far more excess deaths. Estimates of excess deaths in the older population vary widely depending on the period studied, the data sources used and the type of analysis conducted. Another study, published in May in the BMJ (formerly known as the British Medical Journal), calculated 458,000 “excess deaths” in 2020 in the United States. About 72% were people 65 and older, according to the British and American authors.