Studies link adverse drug interactions to elevated risk for hospitalization among the elderly
Research Activities, September 2012, No. 385
The elderly population consumes a disproportionate share of prescription and over-the-counter drugs relative to younger persons. These factors, combined with age-related changes in the ability of the body to process and respond to drugs, make the elderly population more susceptible to drug interactions. A review of 17 studies that assessed specific drug interactions in elderly patients found that 16 of the studies reported an elevated risk for hospitalization in older adults associated with drug interactions.
These interactions included angiotensin-converting enzyme (ACE) inhibitors and potassium-sparing diuretics; ACE inhibitors or angiotensin receptor blockers and sulfamethoxazole/trimethoprim (SMX/TMP); benzodiapines or zolpidem and other medications; calcium channel blockers and macrolide antibiotics; digoxin and macrolide antibiotics; lithium and loop diuretics or ACE inhibitors; phenytoin and SMX/TMP; sulfonylureas and antimicrobial agents; theophylline and ciprofloxacin; and warfarin and antimicrobial agents or non-steroidal anti-inflammatory drugs.
The researchers conclude that when the elderly receive drug therapy, it should be absolutely necessary for the achievement of well-defined goals. They also recommend that an evidence-based, high-priority list of drug interactions in the elderly be developed and maintained. This study was supported in part by the Agency for Healthcare Research and Quality (HS19220, HS17001).
See "Potentially harmful drug-drug interactions in the elderly: A review," by Lisa E. Hines, Pharm.D. and John E. Murphy, Pharm.D. in the American Journal of Geriatric Pharmacotherapy 9, pp. 364-377, 2011.