Numerous studies have established how COVID-19 has neurological ramifications post-infection.
Researchers who looked at health records of 6.2 million adults aged 65 years and above in the US found that the risk of developing Alzheimer’s Disease increased by half compared to those who did not have the infection.
The statistical analysis study by scientists from Case Western Reserve University, Cleveland, USA, did not throw new light on whether COVID-19 triggers a new onset of Alzheimer’s Disease or hastens its advent.
Alzheimer’s Disease is a common cause of dementia and leads to a gradual decline in thinking, behavioural and social skills. This condition affects a person’s ability to function independently.
The same team had previously established that people with Alzheimer’s Disease (who were fully vaccinated) were more susceptible to SARS-CoV-2 infections. “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,” says Dr Pamela Davis, the study’s co-author, in a statement.
Considering these factors, the researchers wanted to explore if COVID-19 infection and Alzheimer’s influence each other.
They analyzed the health records of 6.2 million adults who were 65 years or older in the United States and those who received medical treatment between February 2020 and May 2021. These people had no prior diagnosis of Alzheimer’s Disease.
Researchers divided the population into two groups: those who contracted COVID-19 infections (around 400,000) and those who did not (about five million). Then, they determined the status of Alzheimer’s Disease in the group based on the International Classification of Diseases-10 (ICD-10) diagnosis codes and laboratory tests.
Their analysis revealed that the overall risk of Alzheimer’s Disease in the COVID-19 group was 0.68% compared to 0.35% in the non-COVID-19 group.
The researchers also found that women and people aged 85 and above had the highest predisposition to Alzheimer’s Disease.
From this, the team concluded that older people who got COVID-19 might have a 50% higher risk of developing Alzheimer’s Disease than those who did not get COVID-19.
“So many people in the US have had COVID-19, and the long-term consequences of COVID-19 are still emerging. It is important to continue to monitor the impact of this disease on future disability,” says Dr Davis in the statement.
The research team wants to continue studying the effects of COVID-19 on Alzheimer’s Disease and other neurodegenerative disorders—especially which subpopulations may be more vulnerable—and the potential to repurpose FDA-approved drugs to treat COVID-19’s long-term effects.
