Lack of relationship between long-term use of benzodiazepines and escalation to high dosages.

Abstract

The objective of this study was to determine whether long-term benzodiazepine use is associated with dose escalation. The authors examined changes in dose and the frequency of dose escalation among new and continuing (at least two years) recipients of benzodiazepines identified from a database containing drug-dispensing and health care use data for all New Jersey Medicaid patients for 39 months. Independent variables included age; Medicaid eligibility category; gender; race or ethnicity; neighborhood socioeconomic variables; chronic illnesses, such as schizophrenia, bipolar illness, panic disorder, and seizure disorder; and predominant benzodiazepine received. Logistic regression analyses were conducted to determine the association between the independent variables and escalation to a high dosage (at least 20 diazepam milligram equivalents [DMEs] per day for elderly patients and at least 40 DMEs per day for younger patients). A total of 2,440 patients were identified, comprising 460 new and 1,980 continuing recipients. Seventy-one percent of continuing recipients had a permanent disability. Among all groups of continuing recipients, the median daily dosage remained constant at 10 DMEs during two years of continuous use. No clinically or statistically significant changes in dosage were observed over time. The incidence of escalation to a high dosage was 1.6 percent. Subgroups with a higher risk of dose escalation included antidepressant recipients and patients who filled duplicate prescriptions for benzodiazepines at different pharmacies within seven days. Elderly and disabled persons had a lower risk of dose escalation than younger patients. The results of this study did not support the hypothesis that long-term use of benzodiazepines frequently results in notable dose escalation.