A drug commonly used to manage symptoms of Alzheimer disease and other dementias — donepezil — is associated with a two-fold higher risk of hospital admission for rhabdomyolysis, a painful condition of muscle breakdown, compared with several other cholinesterase inhibitors, found a study in CMAJ (Canadian Medical Association Journal).

Dementia is a growing problem, with almost 10 million newly diagnosed cases every year around the world.

The study, led by researchers at Western University’s Schulich School of Medicine & Dentistry and Lawson Health Research Institute, looked at ICES data from 2002 to 2017 on 220 353 patients aged 66 years or older in Ontario, Canada, with a new prescription for donepezil, rivastigmine or galantamine, three cholinesterase inhibitors used to manage dementia and Alzheimer disease. Researchers found that donepezil was associated with a two-fold higher risk of hospitalization for rhabdomyolysis, a serious condition that can result in kidney disease. The relative risk was small but statistically significant.

“The findings of this population-based cohort study support regulatory agency warnings about the risk of donepezil-induced rhabdomyolysis,” writes Dr. Jamie Fleet, a postgraduate year 4 resident in physical medicine and rehabilitation now at McMaster University, Hamilton, Ontario, with coauthors. “Reassuringly, the 30-day incidence of a hospital admission with rhabdomyolysis after initiating donepezil remains low.

“Risk of rhabdomyolysis with donepezil compared with rivastigmine or galantamine: a population-based cohort study” is published September 16, 2019.