Concomitant use of prescription drugs and dietary supplements in ambulatory elderly people.
OBJECTIVE
To analyze baseline data on concomitant use of prescription drugs and dietary supplements in elderly people from the Ginkgo Evaluation of Memory (GEM) Study, in which information was collected on all drugs and supplements used by participant.


METHODS
Cross-sectional correlation analysis.


METHODS
GEM Study sites in California, Maryland, North Carolina, and Pennsylvania.


METHODS
Three thousand seventy ambulatory individuals aged 75 and older enrolled between September 2000 and June 2002.


METHODS
Use of prescription drugs and dietary supplements identified through bottles brought to the clinic.


RESULTS
Almost three-quarters (74.2%) of the cohort combined use of at least one prescription drug and one dietary supplement, with 32.5% using three or more prescription drugs and three or more supplements. The 15 most-prevalent prescription drugs exhibited substantial concomitant use with dietary supplements, ranging from 77.6% for diuretics to 93.6% for estrogen preparations. Although supplements were taken concomitantly with all classes of prescription drugs, the use of supplements was more likely in individuals using nonsteroidal anti-inflammatory drugs, thyroid drugs, and estrogens. The use of drugs for diabetes mellitus was negatively associated with the use of supplements, with most of this attributed to low use in those taking multivitamins, glucosamine and chondroitin, and echinacea.


CONCLUSIONS
There is substantial concomitant use of prescription drugs and dietary supplements in elderly people. Further investigations are needed to define the clinical importance of this concomitant use, especially in elderly patients who consume multiple prescription drugs or have experienced an adverse event secondary to their prescription medications.
Nahin
Richard L
RL
National Center for Complementary and Alternative Medicine, National Institutes of Health, Bethesda, Maryland 20892, USA. nahinr@mail.nih.gov
Pecha
Monica
M
Welmerink
Diana B
DB
Sink
Kaycee
K
DeKosky
Steven T
ST
Fitzpatrick
Annette L
AL
D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D003704:Dementia / Q000517:prevention & control; D019587:Dietary Supplements / Q000706:statistics & numerical data*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D019338:Polypharmacy; D055553:Prescription Drugs / Q000008:administration & dosage*; D014481:United States
D055553:Prescription Drugs