A recent study published in the British Medical Journal found a correlation between increased risk of dementia and long-term use of certain commonly prescribed drugs. Researchers from the University of East Anglia compared medical records of more than 300,000 pensioners and found that those who took a certain drug – known as anticholinergics – saw a 30% increase in developing dementia. A typical person between 65 and 70-years old has about a 10% chance of developing dementia. But those who took certain anticholinergics saw their individual risk rise to 13%. Researchers viewed this increased risk as statistically significant.
Increased Risk Depends on Treatment Type
Doctors frequently prescribe anticholinergics to treat diseases common among older people. They include procyclidine (Kemadrin) for Parkinson’s; tolterodine, oxybutynin, and solifenacin (Vesicare) for overactive bladder or incontinence; and amitriptyline, dosulepin, and paroxetine for depression. These drugs are so common, that nearly 2 million British citizens use them in one form or another. Not all anticholinergics, however, increased a user’s dementia risk. Some, like antihistamines and drugs used to treat gastrointestinal issues, showed no risk correlation at all.
Exactly why certain anticholinergic medications increased dementia risk isn’t clear. Alzheimer’s patients are known to have low levels of acetylcholine. And some researchers believe anticholinergic drugs might suppress normal acetylcholine in areas of the brain associated with memory and cognition. There’s also evidence that anticholinergics can cause neuroinflammation, which may lead to increased beta-amyloid and tau deposits – the hallmark signs of Alzheimer’s disease.
Researchers Urge Caution
Although these results may seem alarming, researchers stress that correlation doesn’t always equal causation. Just because these drugs are associated with an increased dementia risk, doesn’t mean they’re the cause. And while the increased risk is statistically significant, it’s still less than the risk associated with other modifiable behaviors like smoking, social isolation, and physical activity. So if you’re taking one of these drugs, don’t stop before you talk it over with your own doctor. Researchers do urge doctors to be conservative when prescribing this class of drugs, though, and to take the patient’s overall anticholinergics load into account before prescribing new drugs.
The Dementia Risk is Growing Worldwide
This new study comes as the world continues to grapple with the upcoming wave of expected new dementia cases as the world begins to rapidly age in the coming years. Currently there are 50 million people worldwide suffering from some form of dementia. Researches expect that number to more than triple over the next thirty years. So the stakes are high, and researchers are more motivated than ever to learn what causes dementia and to limit the spread of the disease as much as possible.