CRACK-TARGET 1: Descriptive Study of Observed Behavioral Sensitization and Expectations

Paris region and the French west indies face a specific epidemic of crack-cocaine use, mostly by socially deprived subjects, highly visible in open drug scenes, with little access to the care system. Patients who suffer from crack-cocaine dependence experiment a high rate of medical and a high mortality rate, because this type of cocaine is a short-acting form, used through rapid route of administration (usually smoked or injected).

Nevertheless, despite important uncovered medical needs, they are not often included in clinical trials and there is to date no pharmacological treatment for this severe condition. The investigators identified behavioral disturbances as a key problem in crack-cocaine dependence, as it is the second cause for emergency visits for those patients and a reason to be excluded from addiction care facilities.

Based on preliminary results already gathered by our group, the investigators suggest that behavioral sensitization (BS), an increase of motor response to cocaine after repetitive intermittent use, could be assessed in Humans.

Our goal is therefore to include 20 persons (10 males - 10 females) with a current cocaine use disorder,specifically crack users, with preferential use of rapid administration route (intravenous or smoke), in a care institution: the Fernand Widal Hospital (Assistance Publique - Hôpitaux de Paris). The investigators will assess the movements of crack-cocaine dependent users in relation to consumption. They will have to wear continuously for 3 weeks an actimeter, in the form of a small watch, which collects the level of motor activity throughout the day and night. They will be asked to indicate each moment of crack-cocaine use by pressing the button in the center of the watch. The investigators want to know if certain uses lead to more behavioral problems (especially after periods of cessation).

They will also have 3 blood tests: the investigators want to know if blood proteins, genetic markers passed on by paricipants parents or the expression of proteins in particular situations, could predict this increase in motor effects for small doses of crack-cocaine.

The investigators also want to better understand the needs of crack-cocaine dependent patients towards treatments and their expectations for recovery, by conducting a qualitative study where patients will participate in the definition of treatment aims to increase the efficiency of care

With the project CRACK-TARGET 1 : DETA, the investigators aim at demonstrating the existence of BS in patients with crack dependent subjects. Furthermore, the investigators aim at developing specific, repeatable, easy to access measure of BS using questionnaires and objective actigraphy biomarkers to be used as surrogate endpoints in clinical trials.

• Earlier onset of M10(the time of day when the 10 hours of peak motor activity begins, a reflection of the "motor wake-up time). [Time frame: 3 Weeks]
• Shorter relative amplitude of motor activity (the relative difference between M10) [Time frame: 3 Weeks]
• Self-defined patients' expectations toward treatment measured in qualitative interviews [Time frame: 3 Weeks]
• Higher scores assessed with questionnaires that approximate BS [Time frame: 3 weeks]
• WURS in patients presenting with at least 1 of the 3 previously defition of BS on actimetric measures compared to patients without BS [Time frame: 3 weeks]
• ASRS in patients presenting with at least 1 of the 3 previously defition of BS on actimetric measures compared to patients without BS [Time frame: 3 weeks]
• SAPS-CIP in patients presenting with at least 1 of the 3 previously defition of BS on actimetric measures compared to patients without BS [Time frame: 3 weeks]
• YMRS in patients presenting with at least 1 of the 3 previously defition of BS on actimetric measures compared to patients without BS [Time frame: 3 weeks]
• UPPS in patients presenting with at least 1 of the 3 previously defition of BS on actimetric measures compared to patients without BS [Time frame: 3 weeks]
• PDI in patients presenting with at least 1 of the 3 previously defition of BS on actimetric measures compared to patients without BS [Time frame: 3 weeks]
• PANSS in patients presenting with at least 1 of the 3 previously defition of BS on actimetric measures compared to patients without BS [Time frame: 3 weeks]