SAN FRANCISCO — Medications that are not classically thought of as anticholinergic but that have anticholinergic properties contribute to functional declines in older patients who are on multiple drug therapy.
Investigators tabulated cumulative anticholinergic burden scores for 3,070 adults aged 70 years or older, with each drug scored 0–3 based on serum anticholinergic activity. Every 1-point increase in the anticholinergic burden score was equivalent to adding a year of age as far as patients' ability to complete activities of daily living (ADL) and instrumental activities of daily living (IADL), Dr. Kaycee M. Sink of Wake Forest University, Winston-Salem, N.C., and her associates reported in a poster.
“While one drug in and of itself may not be enough to cause someone disability or functional impairment, if you're on multiple drugs with anticholinergic activities, that might add up,” Dr. Sink said at the annual meeting of the Gerontological Society of America. The cross-sectional analysis used two previously existing lists of dozens of drugs with anticholinergic burden scores, including medications like digoxin and diltiazem that usually aren't thought of as anticholinergic.
The analysis was part of the Ginkgo Evaluation of Memory Study, a randomized, controlled trial of ginkgo to prevent dementia. Previous studies have shown an association between anticholinergic drug use and decreased muscle strength or poorer cognition in older adults, possibly related to the drugs' central effects on psychomotor slowing or their effects at the neuromuscular junction.
In the current study, 39% of participants were taking one or more drugs with anticholinergic activity. In this anticholinergic subgroup, 89% reported their health as good or better with the medications, compared with 96% of participants on no drugs with anticholinergic activity. Hypertension was present in 60% of those in the anticholinergic group and 51% of those in the nonanticholinergic group.
Performance-based assessments of ADL and IADL found that the likelihood of being dependent on help for ADL or IADL increased 10%–15% for every 1-point increase in the cumulative anticholinergic burden score, Dr. Sink said.
The results were adjusted for potentially confounding factors including age, sex, alcohol use, body mass index, hypertension, self-reported health, and clinic site. Effects on gait speed were adjusted for the person's height. Every 1-point increase in the anticholinergic burden score decreased gait speed by 0.009 m/sec.
The study was limited by an inability to completely control for the potentially confounding effects of the indications for the drug use. In addition, the anticholinergic burden scoring system did not consider dose effects.
The investigators will conduct a longitudinal study of whether anticholinergic burden predicts functional decline over time. Results should be available in a year or so, she said. If the anticholinergic burden score can predict who will decline faster, “then I think it would be useful to create a tool that clinicians can use in the office to calculate up each person's anticholinergic score,” Dr. Sink added. “I don't think it would be that hard” to create a computerized tool to assess anticholinergic burden.
Dr. Sink has no association with companies that make the drugs studied.
'If you'reon multipledrugs with anticholinergic activities, that might add up.' DR. SINK