Risk of a new benzodiazepine prescription in relation to recent hospitalization

To determine if recent hospital admission was associated with new outpatient prescribing of benzodiazepines among community-dwelling older people.

Nested case-control study using administrative data sets of the provincial health insurance board.

Province of Quebec.

Cases were 4127 community-dwelling older people who were newly dispensed a benzodiazepine during an 8-month period in 1990. Controls were 16,486 community-dwelling older people who were dispensed any drug (except a benzodiazepine) on the same day as the case-defining index prescription. EXPOSURE AND OUTCOME MEASURES: Admission to an acute care hospital within a 30-day period before a new dispensing of a benzodiazepine. Other variables measured were patient age, gender, number of ambulatory physician visits, healthcare region, Chronic Disease Score (CDS), and use of drugs for depression and psychosis.

Cases were more than three times as likely as controls to have been hospitalized in the 30-day period before the index date (adjusted odds ratio (OR) 3.09; 95% CI, 2.78-3.45). The use of prescription drugs for physical health problems modified this association in that cases who used more medication were also more likely to receive a new benzodiazepine prescription following a recent hospital admission (adjusted OR 4.09; 95% CI, 3.59-4.65 when the CDS was equal to 5 vs adjusted OR 1.96; 95% CI, 1.66-2.31 when the CDS was equal to 0).

Recent hospitalization confers an increased risk of a new outpatient benzodiazepine prescription among community-dwelling older people in Quebec. Those who use more medication, and who may be more vulnerable to drug-related adverse events, are more likely to be newly dispensed a benzodiazepine following a recent, acute-care hospital admission.