Sleep Modifications in Patients With Cocaine Use Disorders Treated With Transcranial Magnetic Stimulation (TMS)

Cocaine use disorder (CUD) is a chronic relapsing brain disorder characterized by a problematic pattern of cocaine consumption leading to a clinically significant impairment. A core element of this disease is the increased vulnerability to relapse during the first weeks of abstinence. Commonly withdrawal symptoms as sleep disturbances, negative affect or craving, may contributes critically to relapses. Especially, sleep disruptions are frequently referred by CUD individuals during either use or abstinence. Moreover, polysomnographic (PSG) data demonstrate a worsening sleep during the first weeks of abstinence in chronic cocaine users, with diminishing rapid eye movement sleep (REM) time, reduction of total sleep time, increasing sleep latency, and chronically decreased slow-wave sleep (SWS) time. Such sleep anomalies appear to be durable and relate to the severity of withdrawal symptoms and clinical outcomes in the treatment of CUD. However, causality between sleep disturbances and CUD has not been clearly established yet. Interestingly, sleep deprivation and addictive substances have comparable neurobiological effects on several neurotransmitter pathways, particularly in the dopaminergic system. Therefore, the implementation of strategies to rewire the altered brain circuits might induce clinically significant improvements of addictive symptoms and the regulation of sleep patterns in CUD patients.

Recently, transcranial magnetic stimulation (TMS), an innovative and safe brain stimulation procedure, which induce neural electrical activity through the application of magnetic pulses over the scalp and with enduring effects on mood, has been applied as a promising therapeutic approach in addictive disorders. In fact, clinical pilot studies on CUD are giving preliminary support to the potential role of rTMS in decreasing cocaine craving and use. PSG studies in healthy volunteers have shown rTMS-induced changes in sleep architecture that are opposites to those found in CUD subjects, as a prolongation of REM latency or a marked increase in slow-wave sleep. The promising therapeutic effect of TMS on insomnia, restless legs syndrome and on sleep disturbances associated to epilepsy, depression and post-traumatic stress disorder has also been suggested. Further, rTMS application over DLPFC have revealed positives outcomes in patients with chronic primary insomnia, by reducing sleep latency, increasing the total sleep time and REM latency.

These findings suggest that rTMS might impact brain circuitry, modulating relevant functions as sleep architecture and potentially affecting addictive related symptoms as craving or negative affect.

The hypothesis of the present study is that rTMS treatment intervention might have a beneficial effect on sleep disturbances reported by CUD patients during the abstinence/withdrawal period. The investigators hypothesized also the positive outcome on accompanied cocaine withdrawal symptoms (as craving or mood) of rTMS.

Hence, the aims of the present study are: