Benzodiazepine use among patients in opioid substituttion treatment: a cross sectional study

Background. – Portugal has one of the highest rates of benzodiazepines (BZD) consumption in Europe. Although the combination of opioid treatment with BZD consumption is generally not recommended, the prevalence use of BZD in opioid-treated patients is still high (45-70%). This study aims to characterize the prevalence and patterning of BZD consumption in opioid substitution treatment.

Methods. – We conducted a cross-sectional study involving 236 patients treated with opioid substitution (methadone and buprenorphine) in the Agualva-Cacém Drug Addiction Treatment Unit. A descriptive analysis was made of the BZD use characteristics.

Results. - The prevalence of BZD consumption was 25.4% (n=60). However, 71.2% (n=168) had a history of lifelong BZD regular use, and the prevalence of BZD consumption at the programme admission was 47.9 % (n=113). Of these, 46.9 % stopped, 35.4 % diminished the BZD use, 13.3% maintained the BZD dose, and only 4.4% increased the dose. Among the BZD users, 83.3% had a regular use (>3days/week), and 85.0% took one BZD type. The most prescribed BZD was Diazepam (29.1%), followed by Alprazolam (15.2%). The BZD were mainly obtained with a prescription (49.8%) or on the black market (42.6%). The main reasons for BZD intake were the hypnotic (27.7%) and anxiolytic (26.9%) effects. Although half of the BZD users consider themselves as having a BZD dependency, 2/3 of those patients had a high level of motivation to stop the BZD intake.

Conclusions. – Our results suggest there was a substantial reduction in current BZD consumption, which highlights the importance of BZD use evaluation of BZD in opioid substitution treatment programmes.