Some common prescription and over-the-counter medicines produce side effects with symptoms that might be mistaken for dementia and other diseases of old-age, says Dr Alistair Burns (University hospital of South Manchester). This is particularly the case for anticholinergic side effects, which are among the most common drug-related effects experienced by elderly people living in nursing and residential homes, he says.
In a review article in the current Journal of the Royal Society of Medicine (2000;93:457), Dr Burns calls for "better understanding, assessment and management" of anticholinergic side effects in elderly people. He lists dementia-like symptoms of confusion, memory loss and disorientation, as well as glaucoma-like blurred vision and other side effects which mimic "old age" conditions. The risk of anticholinergic side effects from certain drugs may be small but elderly patients often take several kinds of medications at once, increasing the likelihood of "anticholinergic load" says Dr Burns. Many illnesses like angina, diabetes, glaucoma and dementia are worsened by medicines with anticholinergic side effects, he adds. Dr Burns points out that physicians often attribute anticholinergic symptoms in elderly people to ageing or age-related illness rather than the effects of drugs.
For most drugs with anticholinergic potential an alternative is available, says Dr Burns. Combinations of drugs with strong anticholinergic activity should be avoided and the use of drugs with minimal anticholinergic side effects from the outset of treatment should avoid the need to switch medication, he advises.