Association of CYP2D6 ultrarapid metabolizer genotype with deficient patient satisfaction regarding methadone maintenance treatment.

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.