TAMPA, Fla. (WFLA) — The COVID-19 pandemic brought change with it, economically, politically, and at times divisively. Some parts of the United States still have varying levels of restrictions for COVID mitigation. Florida formally lifted its COVID-19 restrictions in July 2021, when a law took effect to codify an order ending the mitigation efforts.

New research data shows that seniors who survived COVID-19 infections could have a higher risk of developing Alzheimer’s disease, sometimes as much as an 80% higher risk, when compared to risk before a COVID infection. Even at the low end, there’s a 50% higher risk an older resident will develop Alzheimer’s if they had COVID-19, according to a new study in the Journal of Alzheimer’s Disease.

Florida has more than 22 million residents, and roughly 1 in 5 are seniors, or the age of 65 and older, according to the Florida Department of Elder Affairs. The state saw massive levels of migration during the pandemic as residents flocked to the state seeking new opportunities, different rules for COVID-19, and a place to reestablish themselves.

At one point, migration to Florida reached 850 people per day, according to the legislature. During the COVID-19 pandemic increased population across multiple demographic ages, slightly diluting the proportion of elderly residents. The daily migration has shrunk to 808, according to the state.

In 2020, data from the U.S. Census Bureau showed 21.3% of the residents in Florida were over the age of 65. The total number of deaths to COVID-19 in Florida reached 80,386 as of Sept. 8. More than 61,000 of those deaths were among patients aged 65 or older, according to the Florida Department of Health.

More than one million cases of COVID-19 in the state of Florida have been among seniors, those 65 or older, since March 1, 2020, according to FDOH. Florida’s seniors have had a 24.1% case positivity rate since the start of the pandemic.

Based on the research by Case Western University’s Reserve School of Medicine, risk of Alzheimer’s disease in seniors doubled over a one-year period following a COVID-19 infection.

“The factors that play into the development of Alzheimer’s disease have been poorly understood, but two pieces considered important are prior infections, especially viral infections, and inflammation,” Pamela Davis, Distinguished University Professor, a study coauthor. “Since infection with SARS-CoV2 has been associated with central nervous system abnormalities including inflammation, we wanted to test whether, even in the short term, COVID could lead to increased diagnoses.”

Davis’ study examined 6.2 million patients, aged 65 or more who were given medical treatment from February 2020 to May 2021, with no previous diagnosis of Alzheimer’s disease. The study divided the population into two groups, those who had been diagnosed with COVID-19 and those who had not.

Split up, 400,000 patients in the study had COVID, while 5.8 million were not infected. Rong Xu, professor of Biomedical Informatics at the university’s Reserve School of Medicine, said the effect of COVID-19 on Alzheimer’s disease and other neurodegenerative diseases needed further study.

From the research results, which “examined risks for new diagnosis of Alzheimer’s disease in COVID-19 and non-COVID-19 cohorts in all older adults,” the data showed an increased chance of Alzheimer’s diagnosis following COVID infection.

The “COVID-19 cohort had increased risk for new diagnosis of Alzheimer’s disease compared to matched non-COVID-19 cohort,” showing a shift from a 0.35% chance of Alzheimer’s to 0.68%. The highest risk group were female patients over 85-years-old.

“Older adults with COVID-19 were at significantly increased risk for new diagnosis of Alzheimer’s disease with highest risk in people age ≥85 and in women,” the study said. “Next steps include validation from other data resources, longer-term follow-up, mechanism understanding and examining other types of dementia.”

For Davis, the potential impact of COVID-19 on the population of older Americans is significant.

“If this increase in new diagnoses of Alzheimer’s disease is sustained, the wave of patients with a disease currently without a cure will be substantial, and could further strain our long-term care resources,” Davis said. “Alzheimer’s disease is a serious and challenging disease, and we thought we had turned some of the tide on it by reducing general risk factors such as hypertension, heart disease, obesity and a sedentary lifestyle. Now, so many people in the U.S. have had COVID and the long-term consequences of COVID are still emerging. It is important to continue to monitor the impact of this disease on future disability.”