Zolpidem prescribing and adverse drug reactions in hospitalized general medicine patients at a Veterans Affairs hospital.
BACKGROUND
Zolpidem is prescribed for sleep disruption in hospitalized patients, but data on the incidence of adverse drug reactions (ADRs) are based largely on outpatient studies. Thus, the incidence of ADRs in hospitalized patients may be much higher.


OBJECTIVE
The goal of this study was to describe prescribing patterns of zolpidem for hospitalized medical patients aged 50 years, the incidence of ADRs possibly and probably associated with its use, and the factors associated with central nervous system (CNS) ADRs.


METHODS
This case series was conducted in 4 general medicine wards at a Veterans Affairs hospital and was a consecutive sample of patients aged 50 years who were hospitalized between 1993 and 1997 and received zolpidem as a hypnotic during hospitalization, but had not received it in the previous 3 months. Chart review was conducted by 2 evaluators. Data extracted from the medical records included admission demographic characteristics, medications, comorbidities, and levels of function in performing basic and instrumental activities of daily living. The main outcome measure was ADRs possibly or probably related to zolpidem use. The association between zolpidem and the occurrence of CNS ADRs (eg, confusion, dizziness, daytime somnolence) was analyzed separately.


RESULTS
The review included 119 medical patients aged > or =50 years who had newly received zolpidem for sleep disruption during hospitalization. The median age of the population was 70 years; 86 (72.3%) patients were aged 65 years. The initial zolpidem dose was 5 mg in 42 patients (35.3%) and 10 mg in 77 patients (64.7%). Twenty-three patients had a respective 16 and 10 ADRs possibly and probably related to zolpidem use (19.3% incidence). Of a total of 26 ADRs, 21 (80.8%) were CNS ADRs, occurring with both zolpidem 5 mg (10.8% of users) and 10 mg (18.3% of users). On univariate analyses, the only factor significantly associated with a CNS ADR was functional impairment at baseline (P = 0.003). Zolpidem was discontinued in 38.8% of patients experiencing a CNS ADR CONCLUSIONS: In this case series in medical inpatients, there was a high frequency of ADRs, particularly CNS ADRs, associated with zolpidem use. Zolpidem should be used cautiously in the hospital setting.
Mahoney
Jane E
JE
Section of Geriatrics, Department of Medicine, University of Wisconsin School of Medicine, Madison, Wisconsin, USA. jemahone@facstaff.wisc.edu
Webb
Melissa J
MJ
Gray
Shelly L
SL
D000368:Aged; D002493:Central Nervous System Diseases / Q000139:chemically induced / Q000453:epidemiology; D017723:Drug Utilization Review; D006787:Hospitals, Veterans; D006801:Humans; D006993:Hypnotics and Sedatives / Q000009:adverse effects* / Q000627:therapeutic use; D008499:Medical Records; D008875:Middle Aged; D010818:Practice Patterns, Physicians'; D011725:Pyridines / Q000009:adverse effects* / Q000627:therapeutic use; D000077334:Zolpidem
D006993:Hypnotics and Sedatives; D011725:Pyridines; D000077334:Zolpidem