Study: Patients with Dementia at Higher Risk for COVID-19 Infection, but Not Death

Sydney Jennings

Associate Editor of Patient Care Online

International Stroke Conference 2021

International Stroke Conference: Adults with dementia are more likely to be infected with COVID-19, but no more likely to die from it vs those without cognitive impairment.

Patients with dementia are at an increased risk of SARS-CoV-2 infection, but no more likely to die from COVID-19 that those without cognitive impairment, according to new research being presented at the virtual American Stroke Association (ASA) International Stroke Conference 2021, March 17-19, 2021.

"We found no additional mortality risk other than what you might find due to other underlying health conditions," said lead author Alan Pan, MS, data scientist, Center for Outcomes Research, Houston Methodist Hospital, Texas, in a ASA press release. "Although mortality rates were high for these patients, they were older and had other issues."

Pan and colleagues examined COVID-19 test results, dementia diagnosis, hospitalizations, and mortalities for approximately 180 000 adults at Houston Methodist Hospital between March and December 2020.

Researchers found 6364 adults who had been tested for COVID-19 had some type of dementia, including mild cognitive impairment, Alzheimer disease, and vascular dementia.

Compared to adults without dementia, those who had some type of dementia were approximately 30 years older (mean age, 79 years) and had more underlying conditions, including high blood pressure, heart failure, diabetes, and cancer, according to the study.

Results showed that participants with any type of cognitive impairment were 51% more likely to become infected with SARS-CoV-2 vs those without dementia.

Also, 22.3% of participants with dementia who were hospitalized for COVID-19 died vs 8.6% of those without dementia. However, when matched one-on-one with adults of the same age and who had similar underlying conditions, the gap in death rates, “disappeared,” according to the press release.

These results differ from previous research that found people with dementia have a higher death risk from COVID-19 vs those without dementia, but this might be because of the range of different treatment practices across health systems, said Pan in the press release.

"The strength of our study was in performing those matched analyses," explained Pan. "We wanted to extricate the true effect that cognitive impairment would have."

The study (abstract MP18) results are considered preliminary until published in a peer-reviewed journal.