Longitudinal data showed that hospitalization for infection increased the risk of subsequent dementia diagnosis.
In a 30-year follow-up of approximately 16,000 people, those hospitalized with an infection had a 70% increased risk of subsequent dementia (adjusted HR 1.70, 95% CI 1.55-1.86, P.<0.001), Ryan Demmer (MPH, PhD), University of Minnesota, Minneapolis, and JAMA network open.
The incidence of dementia per 1,000 person-years was 23.6 events (95% CI 22.3-25.0) among those hospitalized with an infection earlier in life compared with those who never experienced a nosocomial infection. was 5.7 (95% CI 5.4-6.0).
“Infection is common and often preventable,” said DeMar MedPage Today“Our results suggest that measures to reduce the risk of infection may also reduce the long-term risk of dementia. It can also help us prioritize patients for the benefit of our patients.”
The findings support recent studies showing that early and middle-aged infections treated in hospital may increase the risk of neurodegenerative diseases such as Alzheimer’s and Parkinson’s.
“Among the many theorized mechanisms contributing to the cause of dementia, neuroinflammation has been recognized as a possible factor,” write DeMar and co-authors.
“For Alzheimer’s disease, the most studied form of dementia, neuroinflammation has been hypothesized to influence disease initiation and progression,” they noted. Several pathogenic mechanisms in the nervous system have been hypothesized to underlie the cause and progression of Alzheimer’s disease.”
Moreover, long-term data from the UK Biobank suggest that SARS-CoV-2 infection may be associated with brain abnormalities and cognitive decline, said Demmer and colleagues. says.
Researchers evaluated 15,688 participants without dementia at baseline in the ongoing prospective study of atherosclerosis risk in the community (ARIC). ARIC participants were followed for up to 32 years from 1987 to 2019. His 19.0% of participants were diagnosed with dementia after his 25.1 years from baseline.
Admission was determined by interview and hospital surveillance. The main exposure was the first occurrence of hospitalization due to infection, according to the ICD code. Participants were considered unexposed until first hospitalized with an infection, after which they became exposed. Dementia cases were identified through ICD codes, telephone interviews, screeners, and face-to-face cognitive tests on a subset of participants.
The mean baseline age of the cohort was 54.7 years. Overall, 55.2% of her participants were female. 26.8% were black and 73.2% were white. The cumulative incidence of hospitalization due to infection before dementia diagnosis was 38.2%.
The incidence of dementia was significantly higher in those hospitalized with respiratory, urinary, skin, blood and circulatory, or nosocomial infections.After adjusting for multiple variables, the top three infections associated with dementia were , blood and circulatory system (HR 2.13, 95% CI 1.45-3.12), urinary tract (HR 1.98, 95% CI 1.76-2.24), nosocomial infection (HR 1.96, 95% CI 1.52-2.51; all P.<0.001).
Overall findings were “consistent and even higher in sensitivity analyzes that excluded those who developed dementia less than 3 years or more than 20 years after baseline or infection-related hospitalization,” Demmer and colleagues said. I observed.
“This analysis reduced the possibility of reverse causation (i.e. undiagnosed dementia leading to infection) by excluding dementia cases identified within 3 years of admission.” “Additionally, cases of dementia occurring 20 years after the hospitalization event may be less relevant.”
The study had some limitations, such as potential residual or unmeasured confounding, the researchers said. Data were not available for several known dementia risk factors, including mild cognitive decline. Infections that did not result in hospitalization were not evaluated.
This work was funded in part by the Intramural Research Program of the National Institute on Aging.
Demmer reported receiving an NIH grant. The co-author reported an NIH grant and his from Medtronic.
JAMA network open
Source reference: Bohn B, et al. Incidence of post-admission dementia due to infection in adults in the community-based atherosclerosis risk (ARIC) study cohort. JAMA Netw Open 2023; DOI: 10.1001/jamanetworkopen.2022.50126.