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.

Electrocardiographic abnormalities in opiate addicts.

AIMS: To determine in a cross-sectional study the prevalence of electrocardiographic (ECG) abnormalities in opiate addicts who were therapy-seeking and its association with demographic, clinical and drug-specific parameters. METHODS: In consecutive therapy-seeking opiate addicts, a 12-lead ECG was registered within 24 hours after admission and evaluated according to a pre-set protocol between October 2004 and August 2006. Additionally, demographic, clinical and drug-specific parameters were recorded. RESULTS: Included were 511 opiate-addicts, 25% female, with a mean age of 29 years (range 17-59 years). One or more ECG abnormalities were found in 314 patients (61%). In the 511 patients we found most commonly ST abnormalities (19%), QTc prolongation (13%), tall R- and/or S-waves (11%) and missing R progression (10%). ECG abnormalities were more common in males than in females (64 versus 54%, P < 0.05), and in patients with positive than negative urine findings for cannabis (68 versus 57%, P < 0.05). Patients with ST abnormalities were more often males than females (21 versus 11%, P < 0.05), had a history of seizures less often (16 versus 27%, P < 0.05), had positive than negative urine findings for cannabis more often (26 versus 15%, P < 0.01) and had negative than positive urine findings for methadone more often (21 versus 11%, P < 0.05). QTc prolongation was more frequent in patients with high dosages of maintenance drugs than in patients with medium or low dosages (27 versus 12 versus 10%, P < 0.05) and in patients whose urine findings were positive than negative for methadone (23 versus 11%, P < 0.001) as well as for benzodiazepines (17 versus 9%, P < 0.05). Limitations of the data are that in most cases other risk factors for the cardiac abnormalities were not known. CONCLUSION: ECG abnormalities are frequent in opiate addicts. The most frequent ECG abnormalities are ST abnormalities, QTc prolongation and tall R- and/or S-waves. ST abnormalities are associated with cannabis, and QTc prolongation with methadone and benzodiazepines.