By: 12 August 2013

Exposure to general anaesthesia increases the risk of dementia in the elderly by 35 percent, says new research presented at Euroanaesthesia.

Postoperative cognitive dysfunction, or POCD, could be associated with dementia several years later. POCD is a common complication in elderly patients after major surgery. It has been proposed that there is an association between POCD and the development of dementia due to a common pathological mechanism through the amyloid ß peptide. Several experimental studies suggest that some anaesthetics could promote inflammation of neural tissues leading to POCD and Alzheimer’s disease (AD) precursors including ß-amyloid plaques and neurofibrillary tangles. But it remains uncertain whether POCD can be a precursor of dementia.

In this new study, Dr Francois Sztark, INSERM and University of Bordeaux, France, and colleagues analysed the risk of dementia associated with anaesthesia within a prospective population-based cohort of elderly patients (aged 65 years and over). The team used data from the Three-City study, which included 9,294 community-dwelling French people.

Participants were interviewed at baseline and subsequently at two, four, seven and 10 years after.

At the two-year follow-up, 33 percent of the participants reported an anaesthesia over the two previous years, with 19 percent reporting a GA and 14 percent a LRA. A total of 632 (nine percent) participants developed dementia over the eight subsequent years of follow-up. The researchers found that demented patients were more likely to have received anaesthesia, and participants receiving at least one GA over the follow-up had a 35 percent increased risk of developing some type of dementia.