Wednesday, May 07, 2008


AGS: A Little Anticholinergic Burden Can Be Disabling

By Peggy Peck
WASHINGTON, 06 may 2008 -- Drugs not usually thought of as anticholinergics -- such as furosemide (Lasix) and diltiazem (Cardizem) -- could lead to functional impairment when taken in combination, researchers reported here.
Each drug has anticholinergic properties and taken together they have an additive effect such that "it would add about four years to functional ability; a 70-year-old would function as a 74-year-old," Kaycee Sink, M.D., of Wake Forrest University in Winston-Salem, N.C., told attendees at the American Geriatrics Society meeting.
Patients who were taking one moderately anticholinergic drug, such as cimetidine (Tagamet), or two mildly anticholinergic drugs -- such as furosemide and diltiazem -- were about 30% more likely to have problems with activities such as dressing or bathing versus same-age people who took no anticholinergic drugs (OR 1.31, 95% CI 1.00 to 1.72), Dr. Sink said.
And they were about 35% more likely to have difficulty with more complex tasks like meal preparation or medication management (OR 1.35, 95% CI 1.07 to 1.72).
Likewise, as anticholinergic burden increased gait speed decreased from 0.89 meters/sec to 0.86 meters/sec, which was statistically significant (P =0.02), Dr. Sink said.
Those findings emerged from the Ginkgo Evaluation of Memory Study (GEMS) study, which recruited 3,070 individuals 75 or older at participating centers in California, Maryland, North Carolina, and Pennsylvania.
Anticholinergic drugs have been associated with poorer cognition and diminished strength in older adults, but, Dr. Sink said, "many drugs have anticholinergic effects, but are not considered anticholinergic drugs and there has been little investigation of the potential anticholinergic burden of these drugs."
This analysis sought to determine what effect -- if any -- the anticholinergic burden of these drugs would have on function.
At baseline, participants were asked about exposure to drugs "on a short list of 52 drugs in which anticholinergic burden had been assessed." A drug with no anticholinergic burden was rated "0", mildly anticholinergic drugs were scored as 1, moderately anticholinergics were rated 2, and highly anticholinergic drugs were classified as 3.
Using this scoring system, fuorsemide received a 1, as did diltiazem. Cimetidine was rated 2 and oxybutynin (Ditropan) received a 3.
To gauge functional level, participants were asked a series of questions about activities of daily living, which were also assessed by a series of observational measures including gait speed.
The researchers determined that 40% of participants were taking one or more drugs with anticholinergic burden, and a small number were taking nine drugs with some anticholinergic properties.
"When the anticholinergic burden score was 2 or higher, which often meant just taking two seemingly innocuous drugs, there was a clear increase in risk of functional impairment," Dr. Sink said.
She noted that the study was limited by its cross-sectional design, which cannot completely rule out confounding by indication for use of anticholinergic medications and by the lack of consideration for dose of anticholinergic drugs.
Nevertheless, Dr. Sink said, clinicians need to be aware of anticholinergic burden even in drugs that are not usually considered anticholinergic medications.
She said that the list of 52 anticholinergic drugs used for the study was based on an expert consensus (Schubert CC, et al JAGS 2006; 54: 104-109) and she suggested that it would be useful "to use this list when assessing medications used by elderly patients."
GEMS, which is assessing the effect of ginko use on memory function, is ongoing and results are expected later this year.
The study was supported by the National Institute on Aging and the National Center for Complementary and Alternative Medicine. Dr. Sinks received support from the Hartford Geriatrics Health Outcomes Research Scholars, the WFU Pepper Center, and the Kulynych Center for Research in Cognition.
Primary source: American Geriatrics Society MeetingSource reference:Sink K, et al "Antihcolinergic burden is associated with worse physical function: Results from the GEM study" AGS Meeting 2008.Complete AGS Coverage

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