Treatment of Opiate Dependence

Illicit and prescription opiate abuse: Improving treatment outcomes. (In progress)

Dependence on opiates is a major health issue in Canada. Among intravenous users, concomitant risks include the transmission of the human immunodeficiency (HIV), hepatitis B and C viruses, and tuberculosis, as well as a high incidence of death due to overdose. The incidence of non-medical use of prescription opioids is rising throughout North America, reaching near-epidemic proportions. Given the high social, health and economic costs associated with opiate dependence, research into effective treatment is a critical clinical and research issue.

The current program of research will provide a novel approach to improving outcomes for opiate dependent patients. There is accumulating evidence that chronic opiate use is associated with the development of hyperalgesia, a state of nociceptive sensitization characterized by increased sensitivity and enhanced pain responses to noxious stimulation. Paradoxically, opioid use aimed at relieving pain may make individuals more pain sensitive over the course of chronic abuse. Hyperalgesic, highly sensitive opiate-dependent patients may experience a great deal of difficulty tolerating opiate withdrawal including the somatic symptoms (fever, chills, pain, muscle cramps), as well as the emotional distress (agitation, anxiety, sleep disturbance) and mood symptoms (dysphoria, irritability) inherent in the detoxification process. The research program will explore the relationships between psychiatric comorbidity, pre-existing pain syndromes and the development of hyperalgesic responses during detoxification, and the role of these factors in treatment outcome. Both short-term outcomes (e.g. drop-out, completion of detoxification) and longer term treatment outcomes (slips, relapses and abstinence) are being examined.

Prior to treatment patients that consent to the study are being assessed in terms of type of opiate abused (illicit street vs. prescription opioids), patterns and amount of substance use, addiction severity, psychiatric problems, impulsivity, psychological distress, general sensory and pain sensitivity via clinical interviews, self-report questionnaires, and objective measures. Subsequently, all patients will be prospectively monitored throughout the detoxification process in terms of craving, mood, objective and subjective withdrawal symptoms, vital signs, subjective experiences of pain, and objective measures of hyperalgesia and allodynia. The study will compare both opiate (illicit vs. prescription opioids) and sedative-hypnotic dependent patients at treatment entry, during detoxification, at the end of detoxification, as well as at 3- and 6-months of follow-up. The study is in progress.