Can we predict addiction to opioid analgesics? A possible tool to estimate the risk of opioid addiction in patients with pain.

BACKGROUND: The use of opioid analgesics in the treatment of chronic pain conditions has long been controversial. They have been reported to be relatively safe when prescribed with caution, but a brief and valid instrument to estimate a person's risk of addiction is still missing.

OBJECTIVE: The aim of this study was to investigate a self-rating questionnaire allowing an estimation of a person's risk of addiction to opioid analgesics.

STUDY DESIGN: Retrospective review.

SETTING: Four Austrian hospitals.

METHODS: Seven hundred forty-one patients were interviewed. Of these, 634 patients were affected with chronic pain while 107 patients had a history of opioid addiction. Patients were interviewed about alcohol and nicotine consumption and family history of psychiatric disorders. Attitudes towards medication and the origin of pain were examined. We asked patients with an opioid addiction and patients suffering from chronic pain to complete a short questionnaire intended to help screen for addiction potential.

RESULTS: Compared to the patients suffering from chronic pain, patients with an opioid addiction significantly more often had alcohol- and nicotine-related pathologies and psychiatric comorbidity. A family history of mental illness and developmental problems were significantly more frequent in this group. Compared to those not addicted, those with an opioid addiction had significantly higher expectations concerning the potential of medication to change one's mental state; they thought that psychological  factors might contribute to the pain they feel.

LIMITATIONS: The main limitation of this study is the use of a self-rating instrument which reduces objectivity and introduces the possibility of misreporting. Also, the 2 groups differ in number and are not homogenous.

CONCLUSION: We found differences in questionnaire responses between patients with an opioid addiction and patients suffering from chronic pain to be dependent upon the prevalence of current or former addiction, psychiatric history, attitudes towards medication, and ideas about the origin of pain. We believe these factors have predictive value in estimating a patient with pain's risk of addiction.