Alzheimer's indicator spikes after surgery

For years, people have talked about the potential of anesthesia being linked to Alzheimer's disease progression without any hard evidence to prove it. With advances in biomarker testing, a small study showed some evidence to support what clinicians have been observing in patients--that surgeries and anesthesia could contribute to the memory-stealing disease.

To test their hypothesis, researchers at the University of Pennsylvania's Perelman School of Medicine tracked the Alzheimer's markers beta amyloid and tau protein in the cerebral spinal fluid of 11 patients who underwent a nasal procedure. The tests found that levels of tau protein, whose rise is associated with disease progression, jump once the surgery ended and continued to rise two days after the procedure. Beta amyloid levels, which actually fall as the disease progresses, did make statistically significant moves one way or the other in the patients.

The researchers also found spikes in the levels of injury biomarker S100B and inflammatory signatures Interleukin-10, IL-6, and tumor necrosis factor in the study patients after surgery, leading them to suspect that neurological inflammation could be a driver.

"We have long sought a clearer picture of the true impact of anesthesia and surgery on the central nervous system," said Dr. Roderic Eckenhoff, Austin Lamont Professor of Anesthesia at Penn and lead study author, in a statement. "Although not definitive, this human biomarker study gives some credibility to the notion that anesthesia and surgery produce an inflammatory insult on the brain and accelerate chronic neurodegenerative diseases like Alzheimer's."

Eckenhoff said that further study of this link between Alzheimer's and surgery in larger numbers of patients is needed to validate the findings of the study, which is published in the journal Anesthesiology this month.

- here's the release