Can repeated anesthesia lead to faster cognitive decline? Research shows mixed results, with some evidence pointing to general anesthesia as a possible risk factor for cognitive issues after surgery, especially in older adults, but no clear proof that multiple exposures speed up long-term decline like dementia.
General anesthesia helps people sleep through surgery, but doctors worry it might affect the brain, particularly in seniors. One study found that surgery under general anesthesia is seen as a risk for long-term cognitive decline. Experts think the drugs used, called volatile anesthetics, along with the surgery stress, might harm the blood-brain barrier. This barrier protects the brain, and inflammation could break it down, leading to problems like postoperative cognitive dysfunction, or POCD. POCD shows up as trouble with attention, learning, and memory right after surgery.
Not all anesthetics are the same. Research comparing desflurane and isoflurane in elderly patients showed desflurane caused less impact on thinking skills after surgery and fewer cases of POCD. Isoflurane seemed to spark more brain inflammation, which hurt recovery. Another trial looked at desflurane versus sevoflurane in people over 60 having non-heart surgery. It checked how fast patients woke up and regained basic cognitive skills, like orientation and memory, using simple tests. Desflurane might allow quicker recovery from anesthesia effects.
POCD often happens soon after surgery, but some call for watching patients up to 30 days or more, renaming it as part of perioperative neurocognitive disorders. Tools like monitoring brain waves with EEG during anesthesia could help protect against longer-term brain issues. A review of studies on light versus deep anesthesia in older surgery patients found some support for lighter levels reducing cognitive problems, though results vary.
Other factors play a role too. For example, obstructive sleep apnea did not clearly link to cognitive decline within 90 days post-surgery in one study. Age, health conditions, and surgery type matter more than anesthesia alone for repeated exposures. While single surgeries raise concerns, evidence on multiple anesthetics speeding overall cognitive decline remains unclear and needs more research.
Sources
https://pmc.ncbi.nlm.nih.gov/articles/PMC12690915/
https://clinicaltrials.gov/study/NCT07289945
https://onlinelibrary.wiley.com/doi/10.1002/brb3.71154
https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2025.1714117/full
https://www.cureus.com/articles/427230-shedding-light-on-depth-a-meta-analysis-of-light-versus-deep-anaesthesia-and-postoperative-neurocognitive-outcomes-in-elderly-surgical-patients
