“Cholinesterase inhibitors are today’s primary therapy for slowing Alzheimer's disease,” said Doctor Denise Boudreau of Group Health Research Institute. “Anticholinergic properties are often found in drugs commonly used to treat gastrointestinal disorders, allergies, urinary incontinence, depression, and Parkinson’s disease, and they can have negative effects on cognition and function in the elderly. There’s concern that if someone is taking both types of drugs - cholinesterase inhibitors and anticholinergic medications - they will antagonize each other, and neither will work.”
Boudreau and colleagues conducted a retrospective cohort study of 5,625 people aged 50 or older who received a new prescription for cholinesterase inhibitors between 2000 and 2007. The researchers used electronic pharmacy records of Group Health Cooperative and Kaiser Permanente Colorado, nonprofit health care systems that together provide care to more than a million people. The research team found patients who also had a prescription for anticholinergics from the year before their cholinesterase prescription until the analysis ended on December 31, 2008, or the patient left the health care system or died. The study was the first to use state death records and insurance claims for nursing home care to look for effects of taking both drug types.
The researchers found:
Of the cholinesterase inhibitor users, 37 per cent were also taking at least one anticholinergic drug, and more than 11 per cent took two or more. This was similar to other studies of Medicare beneficiaries.
For those using both medication types, dual use generally lasted three to four months, but 25 percent used both classes of drugs for more than a year.
Anticholinergics were already being used in 23 per cent of people receiving a new cholinesterase inhibitor prescription, and 77 per cent continued, even after starting the cholinesterase inhibitor.
Subjects using both medication types were not more likely to enter a nursing home or to die than those taking only cholinesterase inhibitors.
“It’s reassuring that we did not observe an association between simultaneous use of the two types of drugs and increased risk of death or nursing home placement,” said Dr. Boudreau. “But concomitant use of these drugs is, at the very least, not optimal clinical practice.”
MEDICA.de; Source: Group Health Research Institute