Adverse Drug Reactions and Elderly

Susan Chen, RPh, PharmD, MS, CGP

10/29/13

ADRs and Hospitalization/ ER Visit

• 5-28% of acute hospital admissions of Geriatric patients are due to ADRs. (Ger. Rv Syllabus, 5^th ed, 2002)
• A meta-analysis study estimated that in 1994 more than 1 million Americans were hospitalized because of adverse drug events (JAMA 1998;279:1200-1205)
• Three most common medications that cause ER visit are: warfarin, Insulin, and digoxin (Ann Intern Med. 2007;147(11):755-765.)

ADRs in Elderly Ambulatory Settings�JAMA,March 5, 2003, Vol 289, No. 9

• What stages: prescribing, monitoring, and patient adherence.
• What medications cause most ADRs :

Cardiovascular medications (24.5%)

diuretics (22.1%),

nonopioid analgesics (15.4%),

hypoglycemics (10.9%),

anticoagulants (10.2%).

ADRs in Elderly ambulatory Settings�JAMA,March 5, 2003, Vol 289, No. 9

What symptoms are most preventable ADRs

Electrolyte/renal (26.6%),

gastrointestinal tract (21.1%),

hemorrhagic (15.9%),

metabolic/endocrine (13.8%),

neuropsychiatric (8.6%)

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ADRs in Elderly Ambulatory Settings�JAMA,March 5, 2003, Vol 289, No. 9

Why Elderly More likely to Experience ADRs?

Elderly change how the drugs work in the bodies (absorption, delivery, metabolism, and elimination), and how the body responses to drugs ( due to organs, liver, GI tract, and renal functions changes)

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Why Elderly More likely to Experience ADRs?

• Renal function deteriorate as aging: 80 yo has 60-80% of renal function of 40 yo.( clinics in ger. Med. 1 1985 207-222.)
• GI malabsorption of medication as aging: increase PH value, decreased GI mobilities, exp: Vitamin B and D.
• Decreased lean body mass as aging: lipid soluble med. stay in the body longer, and water soluble med. shorter.

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Why Elderly More likely to Experience ADRs?

• More drugs taken by elderly: taking two medications has 15% chance of ADRs, and taking five medications has 50 % chance of ADRs. More drug-drug/drug-disease interactions.
• Higher chances of poly-pharmacies, poly-providers.
• Cognitive changes, vision changes, etc.

Beers Criteria-Medications that should be avoided for Elderly

• Based on study of Dr. Beers in 1991.
• Version of 2012 Beers Criteria is an enhanced, evidence based list.
• Try to avoid use the medications if there is an safer alternatives.
• Suggest for providers to monitor the sign/symptoms closely, if the listed medication is used.
• http://www.americangeriatrics.org/files/documents/beers/PrintableBeersPocketCard.pdf

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• Questions?