Abstract
BACKGROUND: Nowadays, the issue of substance abuse is one of the major problems facing most countries in the world. The present study aimed to evaluate the effectiveness of cognitive-behavioral therapy (CBT) on mental health, life expectancy, and happiness in patients receiving methadone maintenance treatment (MMT). MATERIALS AND METHODS: The present study was performed from February 2021 to January 2022. The study was a clinical trial in which 60 people under MMT in psychology clinics in Kashan (Iran) were randomly assigned to the intervention and control groups (30 in each group) using purposeful sampling. Data were collected using the General Health Questionnaire, Schneider Hope Questionnaire, and Oxford Happiness Questionnaire in three stages: baseline, post-treatment, and follow-up. The data were analyzed using a mixed repeated-measures analysis of variance. RESULTS: The results showed that CBT is effective in improving mental health (P < 0.001), increasing life expectancy (P < 0.001), and increasing happiness (P < 0.001) in patients receiving MMT. CONCLUSION: Mental health, life expectancy, and happiness are important and influential issues in the lives of patients under MMT, which are promoted with CBT plus MMT. Therefore, in general, it can be concluded that CBT plus MMT has a significant effect on mental health, life expectancy, and happiness.