NCT03068429

Fear Conditioned Response in Healthy Subjects and in OCD Patients Pre and Post Treatment With Sertraline.

Fear Conditioning, Extinction and Recall in Healthy Subjects and in Obsessive-compulsive Disorder Patients Pre and Post Treatment With Sertraline.

• Status: Completed
• Phase: Phase 4
• Study type: Interventional
• Enrollment: 69 (actual)
• Sponsor: University of Sao Paulo · Academic / Other
• Sex: All
• Age: 18 Years – 65 Years
• Healthy volunteers: Accepted

Summary

24 OCD patients and 24 healthy subjects will be submitted to a two-day fear conditioning paradigm during acquisition of functional magnetic resonance imaging (fMRI). OCD patients will be submitted to the paradigm at two timepoints: baseline and 4 weeks after treatment initiation with sertraline up to 200mg/day or maximum tolerated dosage. OCD patients are expected to demonstrate worsened extinction retention compared to healthy subjects at baseline. Sertraline treatment is expected to improve extinction retention compared to baseline and to normalize the brain regions being recruited with the conditioned stimuli presented during the recall phase.

Detailed description

Fear conditioning paradigms are used to investigate the learning process of the fear response in patients with psychiatric disorders and healthy subjects. Patients with post traumatic stress disorder have been shown to fail to retrieve the memory of fear extinction during the recall phase of the fear conditioning paradigm when compared to healthy subjects. In one previous trial, obsessive-compulsive disorder (OCD) patients have demonstrated the same failure to recall extinction and the results from functional magnetic resonance imaging (fMRI) activation maps have shown different regions being recruited during recall when compared with healthy subjects. However, in that previous trial, some of the OCD patients included were already taking medication for OCD. In the current trial, we will evaluate 24 unmedicated OCD patients with a two-day fear conditioning paradigm before and after 4-weeks of treatment initiation with sertraline up to 200mg/day or maximum tolerated dosage. Sertraline is a first-line treatment option for OCD. At baseline, OCD patients will be compared to 24 healthy subjects. At post treatment, fear conditioning and fMRI results wil be compared to baseline. OCD patients are expected to demonstrate worsened extinction retention compared to healthy subjects at baseline. Sertraline treatment is expected to improve extinction retention compared to baseline and to normalize the brain regions being recruited with the conditioned stimuli presented during the recall phase. By "normalize" we mean that after treatment the regions being recruited will be the same as the ones recruited by healthy subjects during baseline, in other words, differences found at baseline regarding brain activation by the conditioned stimuli are expected to disappear after treatment. Abbreviations: CS= conditioned stimuli, CS+= conditioned stimuli to shock, CS-=neutral conditioned stimuli, CS+E= extinguished conditioned stimuli to shock, CS+U=unextinguished conditioned stimuli to shock

Conditions

• Obsessive-Compulsive Disorder

Interventions

Type	Name	Description
DRUG	Sertraline Hydrochloride	first week: sertraline hydrochloride 50mg/day, second week: sertraline hydrochloride 100mg/day, third week: sertraline hydrochloride 150mg/day, fourth week: sertraline hydrochloride 200mg/day OBS.: Other SSRIs (fluoxetine, paroxetine, escitalopram) with equivalent dosage schedules can be used if patients report prior intolerance to sertraline

Timeline

• Start date: 2016-12-01
• Primary completion: 2019-12-20
• Completion: 2020-07-31
• First posted: 2017-03-01
• Last updated: 2021-04-27

Locations

1 site across 1 country: Brazil