A recent study showed that undergoing hip replacement surgery or abdominal surgery may increase the risk of cognitive decline, including memory loss, in some patients.
In the study, researchers followed 560 people in their seventies who had no signs of dementia when they underwent surgery, and the follow-up continued for six years, with periodic tests to measure memory and mental abilities.
The results showed that about a quarter of the participants had no significant change in their mental abilities after surgery, while 60% suffered a slight decline in mental performance, and 15% experienced a severe deterioration within one month of the operation, which continued to increase gradually during the follow-up years.
Researchers suggest that the slight decline may be part of the natural changes associated with aging, and not necessarily a direct result of surgery.
Those who experienced rapid and severe deterioration were more likely to develop postoperative delirium, a state of confusion and disordered thinking that may appear within days of surgery and may later be associated with an increased risk of cognitive decline.
Some researchers believe that the stress of surgery and the accompanying inflammation may affect the brain, while others believe that surgery may reveal cognitive decline that was already present but went unnoticed.
The operations were distributed between orthopedic surgeries such as knee and hip replacement (about 80%), gastrointestinal surgeries such as hernia repair and gallbladder removal (about 10%), in addition to major vascular surgeries (6%).
All operations were elective, i.e., not emergency, and patients spent an average of three days or more in the hospital after surgery.
The researchers also identified three warning signs that may be associated with severe cognitive decline after surgery: advancing age, poor performance on pre-operative cognitive tests, and post-operative delirium, which was the strongest factor associated with this decline.
The researchers emphasized that the study is observational, meaning it does not prove a direct causal relationship between surgery and cognitive decline, but it does provide important indicators that warrant attention.
The researchers hope these findings will help doctors and patients make more informed decisions by weighing the benefits of surgery against its potential risks to mental abilities.
The study was published in the Journal of the American Geriatrics Society.
