Clinical Correlates of Rapid Eyeball Movement Sleep Behaviour Disorder with Clomipramine: A Case Control Study

Introduction: Antidepressants have been implicated in causing Rapid eyeball movement sleep Behaviour Disorder (RBD). While Selective Serotonin Reuptake Inhibitor (SSRI) and Serotonin Norepinephrine Reuptake Inhibitors (SNRI) are more frequently implicated, Tricyclic Antidepressants (TCA) have been less studied. Aim: To characterise the clinical correlates of RBD on Clomipramine and to compare these parameters with those who didn’t develop RBD on treatment with clomipramine. Materials and Methods: It was a case control study in which participants who were on clomipramine and had developed RBD were studied, and a comparison was made with those participants who were on clomipramine but didn’t develop RBD. All the assessments were done in a single sitting. Patients who were on clomipramine, for any reason, were screened for presence of sleep disorder. Detailed interview was done for diagnosis and Statistical Manual of Mental Disorders (DSM-5) diagnosis of RBD to form the case group. From the group of participants, who didn’t meet the criteria for RBD, every 7th case was included to form the control group (NRBD group). Both the groups were interviewed for socio-demographic and clinical profile and Mini International Neuropsychiatric Interview (MINI Version 5) was applied for International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10) of diagnosis of psychiatric disorders. Chi-square and Independent t-test were used to make the group comparisons. Pearson’s coefficient was used for correlation analysis. Results: A total of 164 participants, on clomipramine, were evaluated for presence of RBD, which was found in 20 and were included in the RBD group and 20 participants, were included in the NRBD group. Mean age of the participants in RBD group was 36.650±7.882 years. Mean duration of RBD development was 16.4 days (Range: 3-40 days). In comparison to the NRBD group, in the RBD group mean dosages (p=0.016), and mean duration of treatment (p=0.026) with clomipramine was significantly higher. Correlational analysis showed that duration of development of RBD correlated negatively with age (r=-0.479, p=0.034) and dosage of clomipramine (r=-0.095, p=0.690). Conclusion: RBD has higher prevalence and younger age of onset with clomipramine usage than earlier reported. Higher dosage increases the chance of developing RBD. Clinicians should be alert for identifying and managing RBD in all patients on antidepressants.