RESUMEN
BACKGROUND: We investigated whether variation in the dopamine D2 receptor gene (DRD2) and tri-dimensional personality questionnaire (TPQ) scores could be used to aid adjustment of daily methadone requirements of heroin addicts. DRD2 TaqI B polymorphisms and TPQ scores were determined in 138 male Taiwanese heroin addicts who were receiving methadone treatment. Borderline index (harm avoidance + novelty seeking-reward dependence) was calculated for each subject, and three groups were defined: high (mean from all subjects plus 1 standard deviation, or greater), low (half of the calculated high score, or lower) and medium (all values between the high and low scores). RESULTS: No significant differences in age (p = 0.60), mean methadone dose (p = 0.75) or borderline index group (p = 0.25) were observed between subjects bearing the B1/B1, B1/B2 and B2/B2 DRD2 TaqI genotypes. Among the individuals with low (≤10), medium (11-20) and high (≥21) borderline index scores, there was a significant difference in mean methadone dose (p = 0.04), but not age (p = 0.90). Further analysis showed that mean methadone dose was significantly higher in subjects with low borderline index scores than in those with high scores (62.5 vs. 47.0 mg/day, p = 0.03). The odds ratio for a daily methadone requirement ≥60 mg (median dose across the 138 subjects) was 2.64-fold greater in the low borderline index group than in the high group (p = 0.04). CONCLUSIONS: Although the DRD2 TaqI B genotype was not associated with methadone use requirements, borderline index was revealed as a potential predictive marker for the adjustment of methadone dosage requirements in heroin addicts.
Asunto(s)
Metadona/metabolismo , Receptores de Dopamina D2/genética , Adulto , Relación Dosis-Respuesta a Droga , Frecuencia de los Genes , Genotipo , Heroína , Dependencia de Heroína/genética , Humanos , Masculino , Metadona/farmacología , Persona de Mediana Edad , Personalidad , Determinación de la Personalidad , Polimorfismo Genético/genética , Receptores de Dopamina D2/efectos de los fármacos , Trastornos Relacionados con Sustancias , Encuestas y Cuestionarios , TaiwánRESUMEN
In an effort to inquiry the "self-medication hypothesis" in heroin-dependent patients suffering from chronic psychosis and bipolar disorder, a naturalistic comparative cohort study was designed with the aim of comparing, according to the presence of dual diagnosis, the clinical characteristics of heroin-dependent patients presenting for their first agonist opioid treatment. The main finding was that addictive (heroin) illness was more severe in bipolar 1 patients and less severe in chronic psychotic patients when compared with heroin-dependent patients without dual diagnoses. In the case of chronic psychotic patients, these differences do not allow us to exclude a therapeutic heroin use, at least at the beginning of their toxicomanic career, with limited progression of their addictive disease. This occurrence seems to be excluded for bipolar 1 heroin-dependent patients, who come to their first agonist opioid treatment with a more severe addictive disease.