Rhys Blakely, Science Correspondent
The Times
Gerry Gajadharsingh writes:
“Polypharmacy (the taking of prescribed multiple medicines) is a known factor for contributing to some of the symptoms that patients present with. The older we get the more medications that seem to be prescribed. Until that is the patient visits a geriatric specialist, often then they are encouraged to reduce the amount of medication both in dosage and number of medicines that they have been taking.
Drugs are powerful chemicals, manipulating our internal biochemistry and can be very useful to manage an array of medical complaints. However, there is always a balance of risks vs benefits, especially when numerous drugs are used together. The permutations of interactions when multiple drugs are used is often incalculable, but some of the side effects and negative drug interactions of the more common drugs are known.
As you can read from the research below, taking certain drugs for depression and bladder problems may well increase the risk of developing dementia.
The conclusion is that If the medicines do cause dementia then the higher risk associated with them suggests that about 10 per cent of new dementia diagnoses could be attributable to exposure to such drugs, the researchers said. This would equate to about 20,000 of the 209,600 new cases of dementia a year in the UK. The researchers said: “This is comparable with other modifiable risk factors for dementia, including 5 per cent for midlife hypertension, 3 per cent for diabetes, 14 per cent for later-life smoking and 6.5 per cent for physical inactivity.”
Doctors should think twice about prescribing drugs commonly used to treat depression and bladder problems after they were linked to an increased risk of dementia, scientists said.
A study found that there was nearly a 50 per cent greater risk of dementia among patients aged 55 and over who had been prescribed strong anticholinergic drugs for three years or more.
This class of drug helps to contract and relax muscles. They work by blocking acetylcholine, a chemical that transmits messages in the nervous system. Guidelines recommend that they should be avoided for frail older people because they can harm memory and thinking. It is still not clear whether these changes are permanent, but scientists said the new research bolstered the case for prescriptions for middle-aged patients to be reviewed regularly.
As many as one in ten adults aged 50 or over regularly uses a drug with anticholinergic properties, the Alzheimer’s Society says. Professor Tom Dening, head of the dementia centre at Nottingham University, where the study was carried out, said: “We found a greater risk for people diagnosed with dementia before the age of 80, which indicates that anticholinergic drugs should be prescribed with caution in middle-aged people as well as in older people.”
The study, published yesterday in the journal JAMA Internal Medicine, looked at the medical records of 58,769 patients with a diagnosis of dementia and 225,574 patients without one.
The results suggest that the drugs were linked to a higher risk of Alzheimer’s and vascular dementia. The team could not say whether the drugs caused the conditions. A link to an elevated risk of dementia was found with anticholinergic antidepressants, antipsychotic drugs, anti-Parkinson’s drugs, bladder drugs and epilepsy drugs.
Professor Tara Spires-Jones, of the University of Edinburgh, who was not involved in the study, said: “Parkinson’s and depression are both risk factors for dementia so it is possible that the increased risk of dementia was due to these diseases and not the anticholinergic drugs being used to treat them.”
No higher risks were found for other types of anticholinergic drug studied, such as antihistamines.
If the medicines do cause dementia then the higher risk associated with them suggests that about 10 per cent of new dementia diagnoses could be attributable to exposure to such drugs, the researchers said. This would equate to about 20,000 of the 209,600 new cases of dementia a year in the UK. The researchers said: “This is comparable with other modifiable risk factors for dementia, including 5 per cent for midlife hypertension, 3 per cent for diabetes, 14 per cent for later-life smoking and 6.5 per cent for physical inactivity.