Cholinesterase inhibitors could result in potentially harmful weight loss among patients taking them for Alzheimer’s disease, according to US researchers.
As a result, clinicians need to account for the risk when prescribing the class of drugs to older adults, they said, highlighting that weight loss was already a significant problem in dementia patients.
“Our study provides evidence… that cholinesterase inhibitors may contribute to clinically significant weight loss in a substantial proportion of older adults with dementia”
The study authors noted that cholinesterase inhibitors – such as donepezil, galantamine, rivastigmine – were the main drug treatments available for Alzheimer’s but claimed they were only marginally beneficial for most patients.
In their study, researchers from the University of California, San Francisco, evaluated data on patients aged 65 or older diagnosed with dementia who received a new prescription for a cholinesterase inhibitor or other new chronic medication.
The primary outcome was timed to a 10-pound weight loss over a 12-month period, as this represented a degree of loss that would be noticed by a clinician and perhaps prompt further action in considering the causes and potential treatments.
A total of 1,188 patients started on cholinesterase inhibitors were matched to 2,189 patients started on other medications.
At 12 months, 78% were still on the inhibitors, compared to 66% for other medications. About 29.3% of patients on the inhibitors experienced significant weight loss, compared to 22.8% of non-users.
These results demonstrated that patients started on the medications had a higher risk of clinically significant weight loss over a 12-month period, compared to matched controls, the study authors said.
Specifically, they noted that one out of every 21 patients treated experienced at least a 10-pound weight loss.
They stated: “Clinicians should take into account the risk of weight loss when weighing the risks and benefits of prescribing cholinesterase inhibitors in patients with dementia.
“In addition, clinicians should monitor for weight loss if these medications are prescribed and consider discontinuing cholinesterase inhibitors if significant weight loss occurs,” they said in the Journal of the American Geriatrics Society.
Lead author Dr Meera Sheffrin added: “This is very relevant to patient care because unintentional weight loss in older adults is associated with many adverse outcomes, including increased rates of institutionalisation and mortality, a decline in functional status, and poorer quality of life.”
James Pickett, head of research at Alzheimer’s Society said: “Cholinesterase inhibitors are helpful to thousands of people with Alzheimer’s disease in managing their symptoms, such as anxiety and concentration, and can improve their ability to continue daily activities.
“Unexplained weight loss can be serious so it is important that this kind of research is done in order that clinicians can be vigilant regarding the potential causes,” he said.