Even several years after exposure, general anesthesia increased the risk of dementia in the elderly, a French study reported.
In a prospective population-based cohort study older adults with at with at least one exposure to general anesthesia over 8 years had an increased risk of developing dementia compared with age-matched adults who were not exposed to anesthesia over the same period (relative risk 1.35, 95% CI, 1.11-1.63), Francois Sztark, MD, PhD, Institut National de la Santé et de la Recherche Médicale and University of Bordeaux, France, and colleagues, reported.
"Several experimental studies suggest that some anaesthetics could promote inflammation of neural tissues leading to [postoperative cognitive dysfunction] and/or Alzheimer's disease precursors including beta-amyloid plaques and neurofibrillary tangles," they wrote. "But it remains uncertain whether [postoperative cognitive dysfunction] can be a precursor of dementia."
The findings were reported in Barcelona at Euroanaesthesia, the annual congress of the European Society of Anaesthesiology.
The team analyzed data from the Three-City study, which assessed dementia risks for more than 9,200 persons age 65 or older who were living in Bordeaux, Dijon, and Montpellier from 1999 through 2001. The cohort was followed for 10 years with interviews at baseline, and years two, four, seven, and 10.
Beginning with the 2-year follow-up 7,008 nondemented participants were asked about exposure to general or local anesthesia since the previous follow-up.
Data were adjusted for confounders such as socioeconomic status and comorbidities.
Patients who developed dementia were significantly more likely to have received anesthesia (37%) than nondemented patients (32%) (P=0.022), they found.
"These results are in favor of an increased risk for dementia several years after general anaesthesia. Recognition of [postoperative cognitive dysfunction] is essential in the perioperative management of elderly patients" the authors wrote.
A long-term follow-up of these patients should be planned, they stated.
The study was supported by Institut National de la Santé et de la Recherche Médicale (INSERM).
- Reviewed by Zalman S. Agus, MD Emeritus Professor, Perelman School of Medicine at the University of Pennsylvania
Euroanaesthesia, European Society of AnaesthesiologySource Reference: Sztark F et al "Exposure to general anaesthesia could increase the risk of dementia in elderly" Euroanaesthesia 2013; Abstract 18AP1-4.