RESUMEN
BACKGROUND: Conflicting associations with heroin dependence have been found involving the A1 allele of dopamine D2 receptor gene (DRD2) TaqI A polymorphism. METHODS: We compared two samples of unrelated Spanish individuals, all of European origin: 281 methadone-maintained heroin-dependent patients (207 males and 74 females) who frequently used non-opioid substances, and 145 control subjects (98 males and 47 females). RESULTS: The A1-A1 genotype was detected in 7.1% of patients and 1.4% of controls (P = 0.011, odds ratio = 5.48, 95% CI 1.26-23.78). Although the A1 allele was not associated with heroin dependence in the entire sample, the frequency of A1 allele was higher in male patients than in male controls (24.4% vs. 16.3%, P = 0.024, odds ratio = 1.65, 95% CI 1.07-2.57). A logistic regression analysis showed an interaction between DRD2 alleles and gender (odds ratio = 1.77, 95% CI 1.15-2.70). CONCLUSION: Our results indicate that, in Spanish individuals, genotypes of the DRD2 TaqI A polymorphism contribute to variations in the risk of heroin dependence, while single alleles contribute only in males.
RESUMEN
OBJECTIVE: The activity of cytochrome P-450 enzyme 2D6 (CYP2D6) could be related to heroin-dependent patient satisfaction with methadone maintenance treatment. We sought to compare satisfaction with the usual methadone treatment in patients who are ultrarapid, extensive or poor metabolizers, according to CYP2D6 genotyping. METHODS: Two hundred and five heroin-dependent patients filled out the Verona Service Satisfaction Scale for methadone maintenance treatment (VSSS-MT), before CYP2D6 genotyping. RESULTS: VSSS-MT overall scores were comparable in the poor metabolizer (N=9) and extensive metabolizer (N=185) groups, although they were higher in poor metabolizers and extensive metabolizers taken together than in the ultrarapid metabolizers (N=11) (p<0.003). Likewise, ultrarapid metabolizers scored higher than the rest of the sample on the VSSS-MT Basic Interventions subscale (p<001). Regarding this subscale, no poor metabolizers felt dissatisfied, and ultrarapid metabolizer males (N=7) reported lower satisfaction than ultrarapid metabolizer females (N=4) (p<0.022). Ultrarapid metabolizer genotype accounted for 4.2% of the variance on the VSSS-MT total scores, and 5.0% on the Basic Intervention scores. CONCLUSION: Heroin-dependent patients who are CYP2D6 ultrarapid metabolizers according to genotyping present deficient satisfaction with methadone maintenance treatment.
Asunto(s)
Citocromo P-450 CYP2D6/genética , Genotipo , Dependencia de Heroína/genética , Metadona/farmacocinética , Narcóticos/farmacocinética , Satisfacción del Paciente , Adulto , Femenino , Frecuencia de los Genes/genética , Dependencia de Heroína/sangre , Dependencia de Heroína/psicología , Dependencia de Heroína/rehabilitación , Humanos , Drogas Ilícitas , Masculino , Tasa de Depuración Metabólica/genética , Tasa de Depuración Metabólica/fisiología , Metadona/uso terapéutico , Persona de Mediana Edad , Narcóticos/uso terapéutico , Factores Sexuales , Detección de Abuso de Sustancias , Trastornos Relacionados con Sustancias/diagnóstico , Trastornos Relacionados con Sustancias/genética , Trastornos Relacionados con Sustancias/psicología , Negativa del Paciente al Tratamiento/psicologíaRESUMEN
BACKGROUND: Impaired inhibition of conditioned response plays a significant role in relapse in addictive behaviors. Although patients and their relatives frequently discuss this behavioral deficit when seeking treatment, no instrument is yet available to measure its severity. The aim of this study was to develop the Impaired Response Inhibition Scale for Alcoholism (IRISA) to assess this impairment in alcohol-dependent patients. METHODS: A preliminary version of the IRISA was administered to a group of 151 patients under treatment at our center. Exploratory factor analysis was conducted using principal component analysis. The validity and reliability of the IRISA were examined. RESULTS: Factor analysis and item refinement led to a definitive 16-item IRISA that accounted for 61.6% of the total variance and revealed Impaired Response Inhibition as a single factor. Psychometric properties of this version of the IRISA scale showed excellent internal consistency (Cronbach's alpha: 0.96), good test-retest reliability (intraclass correlation coefficient: 0.81), and satisfactory convergent, discriminant, and predictive validity. The IRISA has a good correlation with alcohol craving, the severity of alcoholism, and alcohol consumption during the recovery process. CONCLUSIONS: Our initial results with the IRISA suggest that it is a reliable and valid tool to measure impairment in response inhibition to drinking behavior. The IRISA assesses a potentially important aspect of treatment process and outcome.