Getting a hip replacement or abdominal surgery could put you at a higher risk of memory loss, a study has found.
More than 2 million Americans get these surgeries – including 760,000 hip replacements – every year to allow them to move without suffering from pain and boost their quality of life.
But now, Harvard researchers say that one in seven adults who get the procedures may be left suffering from accelerated memory loss.
In a study, scientists tracked 560 adults in their 70s who had no signs of dementia at the time of surgery and for the next six years after their operation. Tests were used to monitor their memory and thinking skills over time.
Overall, a quarter of patients had no noticeable difference in their mental ability after the surgery.
However, 60 percent experienced a minor drop in their mental ability, while 15 percent experienced a sharp drop in their mental ability a month after the surgery and continued to have a gradual deterioration in their mental ability over the following six years.
The researchers said that the minor drop could be explained by normal changes associated with aging.
For patients who had a major decline shortly after the surgery, however, the researchers said these individuals were much more likely to have experienced delirium, a mental state where a person has episodes of confusion and disordered thinking that can develop from hours to days after surgery.
Millions of older Americans get major surgeries every year. Now, a Harvard study suggests that they might accelerate mental decline
Previous studies have repeatedly linked delirium after surgery with a higher risk of cognitive decline and dementia, although it isn’t clear why this is the case.
Some scientists say this is because the stress of surgery and inflammation kick-starts processes that cause the brain to decline, while others say the surgery simply unmasks a decline that had already been going on behind the scenes.
In the study, published in the Journal of the American Geriatrics Society, the patients were 76 years old on average and just over half were women.
Four in five had gone in for an orthopedic surgery – such as a knee or hip replacement – while one in 10 had gone in for a gastrointestinal surgery – such as a hernia repair surgery or a procedure to remove the gallbladder.
Another six percent had a major vascular surgery, such as an artery repair procedure.
All the surgeries were elective, meaning patients chose to have them rather than being required by doctors, and patients stayed in the hospital for at least three days afterward to recover.
For those that had a sharp decline in their mental ability, this was recorded a month after surgery.
Results also revealed three warning signs that a person was likely to suffer from severe mental decline after a major surgery.
As well as delirium, they warned that being older and having a lower score on mental tests before surgery all raised the risk of suffering from major mental decline.
The study was observational and could not prove that major surgery was actually causing cognitive decline.
The researchers said the results could provide valuable information about how major surgery can shape long-term brain health in older adults.
Postoperative neurocognitive disorders (PND), such as delirium or cognitive dysfunction, are a concern for patients and clinicians alike, and something many older adults take into account before undergoing any major surgical procedures.
And now, with more than 20 percent of the US population set to turn 65 years old by 2030, researchers say that analyzing post-surgery brain health matters more than ever.
The physicians behind the study said that, to help families and patients make informed decisions about procedures, it was crucial for them to understand the potential risks of the surgery as well as the benefits.
In the paper, they wrote: ‘Older age, baseline cognitive impairment, and delirium were associated with severe decline, with delirium having the strongest association.
‘Our findings provide valuable information for older patients considering major surgery and may help clinicians target interventions.’
