Benzodiazepine Use Among Patients Receiving Methadone Maintenance Treatment: A Descriptive Study

Purpose: This study aimed to investigate the patterns and characteristics of benzodiazepine (BZD) use among patients receiving methadone maintenance treatment (MMT). Methods: A total of 80 participants (40 with and 40 without BZD use) were recruited from the MMT clinic of the Affiliated Kangning Hospital of Ningbo University between April 2024 and March 2025. All participants were assessed using the BZD Use Questionnaire (BUQ), the Chinese version of Barratt impulsiveness scale (BIS-C), the Self-rating Anxiety Scale (SAS), the Self-rating Depression Scale (SDS), and the Quality of Life Scale for Drug Addicts (QOL-DA). Results: Among 80 initially selected participants, 71 (BZD group: n=39; non-BZD group: n=32) were included in the final analysis after exclusions for invalid data. In univariate comparisons, the BZD group had a significantly higher prevalence of comorbid mental, sleep, and chronic disorders, higher scores on impulsivity (total, motor, and non-planning), anxiety, and depression scales, and lower scores on the total score as well as the psychological and symptoms/side effects domains of the QOL-DA (all P < 0.05). However, after adjusting for potential confounders, multivariate regression analyses indicated that BZD use was independently associated with higher anxiety levels (β = 0.279, P < 0.05) and greater total impulsivity (β = 0.439, P < 0.001). Regarding impulsivity subscales, BZD use was independently associated with non-planning (β = 0.265, P < 0.05) and motor impulsivity (β = 0.345, P < 0.05), but not with attentional impulsivity. No significant independent associations were found between BZD use and depression or any domain of quality of life (all P > 0.05). Conclusion: BZD use was independently associated with higher levels of impulsivity and anxiety after controlling for key comorbidities, but not with depression or QOL. The causal direction between BZD use and increased impulsivity/anxiety in MMT patients remains unclear, potentially reflecting either pharmacological effects or pre-existing higher levels of impulsivity or anxiety.