Given a choice, many people would prefer to have general anesthesia and sleep through surgery rather than have local anesthesia and be awake for the procedure. But this may change their minds—there’s worrisome new evidence that general anesthesia significantly increases a person’s risk of developing dementia. Scarier still, this risk may remain elevated even years after the surgery is over, a recent French study suggests.
The participants, all of whom were 65 or older, were interviewed and examined at the beginning of the study…and then again two, four, seven and 10 years later. Each exam included a cognitive evaluation to screen for dementia. From the two-year follow-up onward, 7,008 nondemented participants were asked at each follow-up whether they had had anesthesia since the last follow-up and, if so, what type they’d received.
Analysis: Over the next eight years, 9% of the study participants were diagnosed with some type of dementia, most often Alzheimer’s disease. After adjusting for other health problems that might have influenced the results, the researchers calculated that receiving general anesthesia at least once during the study increased the seniors’ risk of developing dementia by a startling 35%, compared with participants who did not receive anesthesia.
Caveats: It’s way too early to say whether or not general anesthesia actually causes dementia, but this study does show a worrisome association. What could be behind this link? Researchers suspect that certain anesthetizing drugs promote inflammation of parts of the nervous system and/or trigger formation of beta-amyloid plaques and other precursors to Alzheimer’s disease. As for whether the same long-term risk applies to younger people who receive general anesthesia, only additional research can answer that question.
Exploring safer options: Are you facing surgery or some other medical procedure for which general anesthesia may be used? If the procedure isn’t truly necessary, it’s worthwhile to consider all your nonsurgical options before you agree to go under the knife. If you do need the procedure, ask your doctor whether local anesthesia, a sedative or a relatively new technique called ultrasound-guided nerve block might be an appropriate alternative to general anesthesia. If general anesthesia is unavoidable—or if you received general anesthesia in the past, particularly if you had it repeatedly—it would be wise to talk with your doctor about how the two of you can be on the lookout for early warning signs of dementia in the coming years. For dementia patients, early detection offers the best chance for optimal management of the condition.