Risk factors for adverse drug events among older adults in the ambulatory setting.

UMMS Affiliation

Meyers Primary Care Institute; Department of Medicine, Division of Rheumatology; Department of Medicine, Division of Geriatric Medicine

Publication Date


Document Type



Age Factors; Aged; Aged, 80 and over; Analgesics, Non-Narcotic; Anticoagulants; Anticonvulsants; Case-Control Studies; Diuretics; Drug Therapy, Combination; Female; Humans; Male; Pharmaceutical Preparations; Risk Factors; Sex Factors


Health Services Research | Medicine and Health Sciences


OBJECTIVES: To gather information on patient-level factors associated with risk of adverse drug events (ADEs) that may allow focus of prevention efforts on patients at high risk.

DESIGN: Nested case-control study.

SETTING: Large multispecialty group practice in New England.

PARTICIPANTS: All Medicare enrollees cared for by a multispecialty group practice during 1 year (N=30,397 person-years from July 1, 1999, through June 30, 2000). For each patient with an ADE, a control was randomly selected.

MEASUREMENTS: Data were abstracted from medical records on age, sex, comorbidities, and medication use at the time of the event.

RESULTS: ADEs were identified in 1,299 older adults. Independent risk factors included being female and aged 80 and older. There were dose-response associations with the Charlson Comorbidity Index and number of scheduled medications. Patients taking anticoagulants, antidepressants, antibiotics, cardiovascular drugs, diuretics, hormones, and corticosteroids were at increased risk. In the analysis of preventable ADEs, the dose-response relationship with comorbidity and number of medications remained. Patients taking nonopioid analgesics (predominantly nonsteroidal antiinflammatory drugs and acetaminophen), anticoagulants, diuretics, and anti-seizure medications were at increased risk.

CONCLUSION: Prevention efforts to reduce ADEs should be targeted toward older adults with multiple medical conditions or taking multiple medications, nonopioid analgesics, anticoagulants, diuretics, and antiseizure medications.


J Am Geriatr Soc. 2004 Aug;52(8):1349-54.

Journal/Book/Conference Title

Journal of the American Geriatrics Society

Related Resources

Link to article in PubMed

PubMed ID