Prepulse Inhibition in Cocaine Addiction and Dual Pathologies.

Isis Gil-Miravet,Ana Benito,Isabel Almodóvar,Enrique Ochoa,Alejandro Fuertes-Saiz,Gonzalo Haro

doi:10.3390/brainsci11020269

Abstract

Cocaine addiction is frequently associated with different psychiatric disorders, especially schizophrenia and antisocial personality disorder. A small number of studies have used prepulse inhibition (PPI) as a discriminating factor between these disorders. This work evaluated PPI and the phenotype of patients with cocaine-related disorder (CRD) who presented a dual diagnosis of schizophrenia or antisocial personality disorder. A total of 74 men aged 18–60 years were recruited for this research. The sample was divided into four groups: CRD (n = 14), CRD and schizophrenia (n = 21), CRD and antisocial personality disorder (n = 16), and a control group (n = 23). We evaluated the PPI and other possible vulnerability factors in these patients by using different assessment scales. PPI was higher in the CRD group at 30 ms (F(3, 64) = 2.972, p = 0.038). Three discriminant functions were obtained which allowed us to use the overall Hare Psychopathy Checklist Revised score, reward sensitivity, and PPI at 30 ms to predict inclusion of these patients in the different groups with a success rate of 79.7% (42.9% for CRD, 76.2% for CRD and schizophrenia, 100% for CRD and antisocial personality disorder, and 91.3% in the control group). Despite the differences we observed in PPI, this factor is of little use for discriminating between the different diagnostic groups and it acts more as a non-specific endophenotype in certain mental disorders, such as in patients with a dual diagnosis.

Highlights

Behind cannabis, cocaine is the second most widely used illicit drug in the European Regional Development Fund (EU)
Our objectives were to determine the relationship between prepulse inhibition (PPI) and cocaine-related disorder (CRD), either alone or as a dual pathology (DP) with schizophrenia or antisocial personality disorder (APD), compared with healthy individuals and to examine if PPI can discriminate between controls and patients with CRD with or without schizophrenia or APD
The overall score was significantly lower in the controls compared to the other groups (p < 0.001) and in the CRD and CRD + SCZ groups compared to the CRD + APD group (p < 0.001). These results suggest the following ascending psychopathy pattern: control < CRD + SCZ ≈ CRD < CRD + APD, CRD + SCZ scores were significantly higher than CRD in the secondary Levenson Self-Report Psychopathy Scale (LSRP) factor and the Psychopathy Checklist Revised (PCL-R) interpersonal/affective factor

Summary

Introduction

Cocaine is the second most widely used illicit drug in the EU. Around four million Europeans aged 15–64 used cocaine last year [1]. Cocaine addiction is frequently associated with several psychiatric disorders, especially schizophrenia (SCZ) and antisocial personality disorder (APD) [2,3], and other public health problems—often with serious social and economic consequences [4]. Cocaine users tend not to respond to treatments and often relapse [5,6,7]. Not all cocaine users become addicted and not all patients with cocaine-related disorder (CRD) develop a psychiatric comorbidity, or dual pathology (DP) [3]. Identifying predisposing factors or endophenotypes for CRD and DPs would aid our understanding of vulnerabilities to CRD and DPs and help the development of risk factor-based prevention and treatment strategies [7,8,9,10,11]

Objectives

Methods

Results