A prospective study of falls after benzodiazepine use: a comparison of new and repeat use.

Although research has consistently demonstrated an increased risk for falls and fall-related fractures among persons receiving benzodiazepine (BZD) medications, the association between new as compared with chronic use and fall-related morbidity among different age groups is less clear. The objectives of this prospective cohort study were to examine the associations between BZD sedative and tranquillizer use and fall-related hospitalizations within 28 days of the fill date, and to explore variations in risks among new (after the first prescription) and chronic (after the third prescription) BZD users of different ages. Data were derived from the Saskatchewan Health linked databases for the years 1979-1986. Fall rates increased with age (especially beyond 70 years) and were highest among those receiving BZD sedatives and tranquillizers compared with controls for both new and chronic users. After adjusting for age, sex and selected health and social factors, a significantly increased risk of fall-related hospitalization was found among new BZD sedative (OR=2.8) and tranquillizer (OR=2.0) users compared with controls, and this risk was only slightly reduced among chronic BZD sedative (OR=2.4) and tranquillizer (OR=1.6) users. These risk estimates were consistent across age, with the exception that chronic BZD tranquillizer use remained significant only among those aged 70 years and older.