Adverse drug reaction (ADR) occurrence and evaluation in elderly inpatients.

OBJECTIVE: Determine elderly inpatient's risk ADRs and characterize the events. DESIGN: This is a post-hoc analysis of a comprehensive inpatient ADR survey. Charts were reviewed every four days on all internal medicine service inpatients (1024 patients over four months). Chart review were enhanced by potential indicators such as nurses' and pharmacists' reports; targeted drug orders; 'now', 'stat', and 'hold' orders; off-service physician consults; incident reports; transfers-to-ICU; and abnormal serum drug concentrations. Potential ADRs were classified according to organ system affected, pharmacological type, severity, and Naranjo causality scale. SETTING: Internal medicine wards of a 350-bed county general hospital. RESULTS: Of 1024 inpatients, 301 were elderly. Overall, 237 patients had an ADR (23%). Elderly patients accounted for 89 (37.5%) of the 237 patients experiencing an ADR. The ADRs experienced by the elderly tended to be more severe (p <0.05) and less idiosyncratic (p <0.05). However, no preferences for organ system (p >0.1) or differences in causality rating (p = 0.25) were detected. When statistically controlled for female gender, renal function and number of drugs, age was no longer a risk factor for ADR occurrence. CONCLUSIONS: The elderly experience more ADRs. However, female gender, decline in renal function and polymedicine are the independent factors that account for the elderly's risk. Furthermore, the elderly's ADRs tend to be more severe and an extension of the drug's pharmacology. Therefore, ADR prevention is both important and possible.

Incidence of adverse drug reactions in adult medical inpatients.

This study was a prospective observational study of ADR occurrence and evaluation in adult internal medicine inpatients conducted over a 120-day period. Clinical pharmacists screened for ADRs at a county hospital in Indianapolis, IN. Patient information was reviewed on admission, every four days during hospitalization, and at discharge. ADRs occurring after hospital admission were assessed for causality, severity, pharmacological type (i.e., augmented pharmacology versus idiosyncratic reaction) and affected organ system. Nurse and pharmacist reports, incident reports, physician consults, patient transfers to critical care units, and serum drug concentration reports were additional means of ADR identification. Overall, 23.1% of patients experienced an ADR while 2.6% of the 11,702 drug exposures resulted in an ADR. Patients aged greater than 65 years (29.6% vs. 20.5% for younger patients) and females (26.2% vs. 20% for males) were at higher risk for ADR development (p < 0.05). Length of hospital stay was longer (13.3 days vs. 6.7 days; p < 0.05) and drug exposures more frequent for patients experiencing ADRs (p < 0.001). Furosemide elicited the most ADRs with 36 in 244 patient exposures (14.7%). Diltiazem, enalapril, heparin, trimterene/hydrochlorothiazide combination and captopril were also frequently implicated. ADRs were classified as mild (35.9%), moderate (52.6%), and severe (10.2%). Organ systems most commonly affected were the metabolic/hematologic (32.9%), gastrointestinal (17.8%), genitourinary (11.8%), and cardiovascular (10.5%). Over 30% of events were idiosyncratic reactions. ADR incidence was consistent with previous literature. Many frequently implicated medications were newer agents and the severity of events was less than previously reported.

Aminoglycoside dosing in pediatric patients.

We assessed the performance of a predictive algorithm for dosing aminoglycoside antibiotics in 75 pediatric patients and Bayesian feedback in 36. The absolute errors for peak and trough concentrations were 1.83 and 0.80 micrograms/ml, respectively, which seem clinically acceptable for most patients. However, the algorithm had significant negative bias for both peaks and troughs. Implementation of Bayesian feedback eliminated bias in a second set of concentrations and significantly decreased its magnitude for both peaks (p = 0.028) and troughs (p = 0.005). This method may allow more accurate dosing of aminoglycoside antibiotics in pediatric patients, though it would most likely be improved by better definition of population parameters and their variability.