Methods
Psychiatric, tremor, agitation, insomnia, DSM-5, obsessive-compulsive disorder
ADVERSE EFFECTS, SECONDARY, DISORDERS, BRAIN
This 12-week randomized, double-blinded, placebo-controlled, parallel-group clinical trial was conducted in the out-patient clinics of (1) Iran Psychiatric Hospital, (2) Rasool-Akram Hospital, and (3) Tehran Institute of Psychiatry, and (4) the Brain and Cognition Clinic (affiliated with Iran University of Medical Sciences, Tehran, Iran) from April to November 2022.Participants enrolled in the study were randomized using the block method (allocation ratio 1:1, blocks of four). Treatment allocation concealment was ensured by using sequentially numbered, opaque sealed envelopes. Participants, outcome assessors, and the statistical analyst were separate individuals blinded to allocation. Additionally, placebos had identically matched size, shape, color, odor, and pharmaceutical packaging with the agomelatine tablets.Participants were men and women, aged between 18 and 60 years, diagnosed with obsessive-compulsive disorder based on the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) criteria [The parallel groups were randomly assigned with sertraline 200 mg/day and either agomelatine 25 mg/day or placebo for 12 weeks. Sertraline was started at 25 mg/day and if tolerable, up-titrated to 100 mg/day for the first four weeks, and 200 mg/day for the next eight weeks.We used the Persian version of Y-BOCS [The primary outcome measure was the mean difference between the Y-BOCS total scores between the two groups from baseline to the twelfth week. The secondary outcome measures were (1 and 2) mean differences between the Y-BOCS obsession and compulsion subscales scores between the two groups from baseline to the twelfth week, and (3) frequency and severity of adverse effects in the two groups.We monitored the treatment-related adverse effects during every patient visit. This comprehensive evaluation involved both patient self-reports and careful observations by the attending psychiatrist. If a medication became intolerable or posed a life-threatening risk to the patient, resulting in the discontinuation of treatment, it was categorized as severe. All other adverse effects were categorized as non-severe. It was agreed that in case of insomnia, oxazepam 10 mg, and in case of tremor or agitation [By using a between-groups difference of 5 in the Y-BOCS score, a 95% confidence interval, a power of 80%, and an attrition rate of 20%, a sample size of 44 (22 in each group) was calculated with G-power 3.1.9.2 [Continuous variables are presented as mean ± standard deviation. Categorical variables were analyzed by Pearson’s Chi-squared test and Fisher’s exact test. The mean differences of the Y-BOCS scores among each group were calculated using the paired sample t-test. The mean differences of the Y-BOCS scores between the groups were calculated using the Independent T-test. Cohen’s d effect sizes were calculated. Group-by-time interaction effect was evaluated using the repeated measures ANOVA, through a general linear model algorithm. Cohen’s d effect sizes were calculated. A p-value of 0.05 or less was considered statistically significant. All statistical analyses were performed with the Statistical Package for the Social Sciences (SPSS) software for Windows (version 24, SPSS Inc., Chicago, IL, USA).