1. 2006;9;215-226Controlled Substance Abuse and Illicit Drug Use in Chronic Pain Patients: An Evaluation of Multiple Variables
   A Prospective Evaluation
   Laxmaiah Manchikanti, MD, Kimberly A Cash, RT, Kim S Damron, RN, Rajeev Manchukonda, BDS, Vidyasagar Pampati, MSc, and Carla D McManus, RN, BSN.

Background: Opioids are used extensively for chronic pain management in the United States. The frequency of opioid use prior to presenting to interventional pain management settings and in interventional pain management settings has been shown to be above 90%. Opioid abuse has been demonstrated in 9% to 41% of patients receiving chronic pain management. Illicit drug use has been reported in 14% to 34% of patients in chronic pain management settings.

Objectives: To evaluate and correlate multiple variables with opioid abuse and illicit drug use.

Design: A prospective, consecutive study.

Setting: Interventional pain management practice setting in the United States.

Methods: A total of 500 consecutive patients prescribed opioids, considered to be receiving stable doses of opioids supplemental to their interventional techniques were evaluated for opioid abuse and for illicit drug use.

Abuse was defined as a patient receiving  controlled substances from any source other than the prescribing physician at our center with the exception of controlled substances for acute injuries unrelated to the problem being treated, or for emergencies.

Urine drug testing for illicit drugs was performed by urine rapid drug screen (Instant Technologies, iCup® Norfolk, VA). Results were considered positive if one or more of the monitored illicit drugs including cocaine, marijuana (THC), phencycledane methamphetamine or amphetamines were detected.

Results: Opioid abuse was seen in 9% of patients, with illicit drug use in 16% of patients. Significant differences were noted in the prevalence of opioid abuse in patients who developed chronic pain following motor vehicle accident(s) and in patients presenting with pain in three regions of the body. Illicit drug use (marijuana) was more common in females. Illicit drug use was also more common in patients younger than 45, after motor vehicle injury, and in patients with involvement of three regions of the body.

Conclusion: Opioid abuse and illicit drug use were common in chronic pain patients with a prevalence of 9% and 16%, respectively. Age, pain after motor vehicle accident, involvement of multiple regions and past history of illicit drug use were identified as risk factors.