Dementia patients have twice the risk of COVID-19

Dementia patients had a significantly increased risk for COVID-19 and that risk was even greater for African Americans with dementia, a retrospective analysis of data from the US electronic health record (EHR) showed.

After adjusting for age, sex, race and COVID-19 risk factors, including comorbidities and staying in a nursing home, people with dementia had twice the risk of developing COVID-19 than other adults (adjusted OR 2.00, 95% CI 1.94-2.06, FOR<0.001), according to Rong Xu, PhD, of the Case Western Reserve University School of Medicine in Cleveland, and coauthors.

Among people with dementia, African American patients were almost three times more likely to be infected with SARS-CoV-2 than white patients (adjusted OR 2.86, 95% CI 2.67-3.06, FOR<0.001), they reported in Alzheimer’s & Dementia.

The 6-month mortality risk for patients with dementia and COVID-19 was 20.99%. The risk of hospitalization was 59.26%.

“We identified patients with dementia as a group that is especially vulnerable to becoming infected with SARS-CoV2,” said co-author Pamela Davis, MD, PhD, also from Case Western Reserve University. “Once infected, these patients are especially vulnerable to serious illness and death from COVID.”

“Both vulnerabilities occur in addition to known concomitant risk factors for COVID, such as nursing home life, old age, hypertension and diabetes,” said Davis MedPage Today. “Physicians should be aware of this increased risk and take all additional measures they can to protect this vulnerable population, such as vaccination, masking and careful attention to the masking and social distance from caregivers.”

The findings illustrate known health disparities that must be addressed, said Carl Hill, PhD, MPH, director of diversity, equity and inclusion at the Alzheimer’s Association in Chicago, which was not involved in the study.

“We know that African Americans are disproportionately affected by Alzheimer’s disease and COVID-19, and this article suggests that African Americans with dementia are three times more likely to get COVID-19 than whites,” said Hill MedPage Today. “This can be explained by the African American’s increased risk of comorbidities associated with dementia, such as diabetes and hypertension, which can make them more vulnerable to severe and symptomatic cases of COVID-19.”

In their analysis, Xu and the co-authors used EHR data from 360 hospitals and 317,000 providers across the U.S., incorporating records from 61.9 million patients from the beginning of the pandemic in February until August 21, 2020. In total, 1,064,960 people had dementia, including 351,590 people with Alzheimer’s disease, 172,630 with senile dementia, 126,450 with post-traumatic dementia, 117,860 with vascular dementia and 31,960 with pre-senile dementia.

Of 15,770 people diagnosed with COVID-19, 810 had dementia. The highest risk was for patients with vascular dementia (adjusted OR 3.17) followed by pre-senile dementia (adjusted OR 2.62), senile dementia (adjusted OR 1.99), Alzheimer’s disease (adjusted OR 1.86) and post-traumatic dementia (adjusted OR 1.67; all FOR<0.001).

Among people with COVID-19 and dementia, the risk of hospitalization during the 6-month study period was 73.08% among African American patients and 53.85% among white patients (FOR<0.01). The mortality risk for people with COVID-19 and dementia was 23.08% for African Americans and 19.23% for white patients.

Overall, the 6-month mortality risk for people with dementia and COVID-19 (20.99%) was higher than for people with COVID-19, but not with dementia (4.81%, FOR<0.001), or for people with dementia, but not COVID-19 (7.64%, FOR<0.001).

More work is needed to understand what leads to the increased risk of COVID-19 in patients with dementia, Davis said. The results have several limitations, the researchers noted: EHR data may be subject to underdiagnosis, overdiagnosis or incorrect diagnosis. The study had limited information on socioeconomic and lifestyle determinants, and looked at only people who had contact with health systems, added Xu and colleagues. The findings are not causal and unknown confounding factors may have influenced the results.