To determine the risk factors for aminoglycoside toxicity in the elderly.DESIGN
Prospective observational study.SETTING
Acute care teaching hospital serving predominantly veterans.PARTICIPANTS
Consecutive patients aged 70 years and over receiving aminoglycosides.INTERVENTIONS
None.MEASUREMENTS AND MAIN RESULTS
Thirteen (15%) of 88 patients developed aminoglycoside-related nephrotoxicity and 3 (3.4%) developed otovestibular toxicity. Multivariate analysis showed that increasing duration of aminoglycoside therapy was the only factor significantly associated with development of toxicity. Elevated baseline serum creatinine level (p=.02) and use of allopurinol (p=.03) were risk factors specifically for nephrotoxicity. Only 2 (3.9%) of 51 patients receiving aminoglycosides 7 or fewer days developed nephrotoxicity, as compared with 11 (30%) of 37 receiving the drugs for 8 to 14 days and 4 (50%) of 8 treated for more than 14 days.CONCLUSIONS
Although toxicity is common in elderly patients treated with aminoglycosides, limiting the duration of aminoglycoside therapy to less than a week can substantially reduce risk of toxicity.