Nikhil Prasad Fact checked by:Thailand Medical News Team Jun 22, 2026 1 hour, 8 minutes ago
Medical News: A major new study involving more than one million adults has found that people who contract COVID-19 may face a higher risk of being diagnosed with dementia, particularly if their infection is severe enough to require hospitalization. The findings add to growing concerns about the potential impact of COVID-19 on long-term brain health and cognitive function among older adults.
Large population study finds COVID-19 infection is linked to a higher risk of dementia, particularly among hospitalized patients
The study was conducted by researchers from the School of Public Health, Faculty of Social Welfare and Health Sciences at the University of Haifa; the Department of Obstetrics and Gynecology at Carmel Medical Center; the Statistical Unit at Lady Davis Carmel Medical Center; the Department of Community Medicine and Epidemiology at Lady Davis Carmel Medical Center; the Ruth and Bruce Rappaport Faculty of Medicine at the Technion-Israel Institute of Technology; and the Translational Epidemiology Unit and Research Authority at Lady Davis Carmel Medical Center, all located in Haifa, Israel.
More Than One Million Adults Studied
To investigate whether COVID-19 affects dementia risk, researchers analyzed health records from Israel's largest healthcare organization. The study included more than 1.14 million adults aged 50 years and older who had no history of dementia when the COVID-19 pandemic began.
During the follow-up period, 27,280 individuals developed dementia. These cases were compared with 272,800 matched individuals who did not develop dementia.
The results showed that a history of COVID-19 infection was associated with an 18 percent higher likelihood of receiving a dementia diagnosis compared to people who had never been infected.
Hospitalized Patients Had the Highest Risk
The increased risk was not observed equally across all COVID-19 cases. Researchers found that individuals who experienced mild COVID-19 and were not hospitalized did not have a significantly higher dementia risk. However, those who required hospitalization faced a dramatically different outcome.
Patients hospitalized with mild COVID-19 were found to have a 139 percent higher risk of developing dementia. Those hospitalized with moderate-to-severe disease had a 93 percent higher risk.
These findings suggest that severe illness and hospitalization may play a critical role in triggering cognitive decline or accelerating the recognition of underlying brain disorders.
Risk Was Strongest Shortly After Infection
One of the study's most important findings was the timing of dementia diagnoses following COVID-19 infection.
The researchers found that dementia risk was highest during the first three months after infection, when the likelihood of receiving a dementia diagnosis increased by 32 percent. Between three and six months after infection, the risk remained elevated by 15 percent.
However, after six months, the association was no longer statistically significant.
This pattern suggests that COVID-19 may eithe
r accelerate the appearance of cognitive symptoms in vulnerable individuals or bring previously undetected cognitive problems to medical attention during the recovery period.
Is COVID-19 Damaging the Brain?
Scientists believe several biological mechanisms may help explain the connection between COVID-19 and dementia.
Previous research has shown that SARS-CoV-2 can trigger widespread inflammation throughout the body, including the brain. The virus has also been linked to blood vessel damage, immune system activation, neuroinflammation, and disruptions in brain function. Some studies have suggested that COVID-19 may promote processes associated with neurodegenerative diseases, including the accumulation of toxic proteins linked to Alzheimer's disease.
Severe infections can also reduce oxygen levels in the body and place significant stress on the brain, potentially increasing the risk of cognitive impairment.
Similar Patterns Seen with Other Serious Infections
The researchers also examined pneumonia as a comparison. They found that pneumonia was associated with a substantial increase in dementia risk as well, especially among patients who required hospitalization. This suggests that severe respiratory infections may share common pathways that contribute to cognitive decline.
As a result, the researchers caution that the elevated dementia risk may not be unique to COVID-19 but could reflect broader effects of serious infections, hospitalization, inflammation, and acute illness.
Conclusions
The study provides compelling evidence that COVID-19 infection is associated with a significantly higher likelihood of dementia diagnosis, particularly among individuals who require hospitalization. The findings indicate that the greatest risk occurs within the first few months after infection, suggesting that acute illness and its consequences may play a major role. While the exact biological mechanisms remain under investigation, the results highlight the importance of monitoring cognitive health in older adults recovering from COVID-19. As millions of people worldwide continue to be exposed to SARS-CoV-2, understanding its potential effects on brain health remains a critical public health priority.
The study findings were published in the peer reviewed journal: Influenza and Other Respiratory Viruses.
https://onlinelibrary.wiley.com/doi/10.1111/irv.70277
For the latest COVID-19 news, keep on logging to Thailand
Medical News.
Read Also:
https://www.thailandmedical.news/articles/coronavirus
https://www.thailandmedical.news/articles/long-covid
Share
Tweet
Share
