Characteristics associated with benzodiazepine usage in elderly outpatients in Taiwan.

OBJECTIVE: To investigate benzodiazepine usage and the characteristics associated with usage among elderly outpatients in Taiwan.
METHODS: This was an observational study of subjects who were enrolled in the National Health Insurance program and aged at least 65 in 2002. They were grouped according to treatment period and mean dosage. An ordered logit regression model was used to evaluate associations of characteristics with benzodiazepine usage.
RESULTS: Of the 4,267 elderly people included, 1,826 had received at least one prescription for benzodiazepines. The 1-year prevalence of benzodiazepine usage by elderly outpatients was approximately 43%. Characteristics associated with receiving benzodiazepine therapy included female gender, displaying comorbid insomnia, anxiety, depression, other mental diseases, cardiovascular disease, cancer, chronic obstructive pulmonary disease, arthritis, and previous use of benzodiazepines. Individuals older than 75 years, with comorbid insomnia, anxiety, depression, other mental diseases, cardiovascular disease, cancer, being in previous receipt of benzodiazepines, or high prescription-overlap ratio were more likely to receive longer treatment. Individuals with insomnia, anxiety, depression, and previous use of higher cumulative dosage of benzodiazepine were more likely to receive higher-dosage therapy.
CONCLUSIONS: Mental disorders and previous exposure to higher cumulative dosages of benzodiazepines are associated with an increased likelihood of receiving benzodiazepine therapy, longer treatment, and a higher mean dosage. Older individuals, less likely to receive higher dosage benzodiazepine therapy, are more likely to receive more prolonged therapy. Women are more likely to receive benzodiazepine therapy, but both men and women have comparable benzodiazepine usage patterns.