NEW YORK (Reuters Health) – Among chronic pain patients prescribed opioid pain medications by primary care physicians, nearly 4% of patients abuse the drugs, according to a large epidemiologic study conducted in Wisconsin. The findings also suggest that a common characteristic of these patients is "aberrant drug behavior," such as requesting early refills or purposely oversedating themselves.
Dr. Michael F. Fleming, at the University of Wisconsin in Madison, and his associates point out in the July issue of The Journal of Pain that a large number of patients have severe, incapacitating pain that cannot be controlled without daily opioid therapy. The researchers investigated substance abuse disorders in this population.
For their study, sponsored by the National Institute on Drug Abuse, they recruited and interviewed 801 subjects from 235 primary care practices. Inclusion criteria were chronic non-cancer pain and daily opioid use for at least 3 months.
The mean age was 48.6 years, and average duration of chronic pain was 16 years. Nearly half had degenerative arthritis and chronic low back pain. Other common conditions were migraine headache, neuropathy, and fibromyalgia.
Opioids most frequently prescribed were oxycodone preparations, making up nearly 60% of the prescriptions, followed by hydrocodone and morphine.
According to scores on the Substance Dependence Severity Scale, 30 patients (3.8%) met criteria for opioid use disorder. That compares with a rate of 0.9% reported in the general population.
The most significant predictor of abuse was aberrant drug behaviors (adjusted odds ratio 48.27, p < 0.001). These included deliberate oversedation, feeling intoxicated by the medication, using opioids for non-pain reasons, and raising the dose without authorization.
Dr. Fleming’s group cautions that these behaviors could also represent inadequate pain treatment, untreated psychiatric illness, chemical coping, and situational stressors.
Although the frequency of opioid use disorders is "of concern," Dr. Fleming and his colleagues conclude that their data "support the use of opioids for the treatment of chronic pain by primary care providers." They maintain that "considering the potential benefit to improving the lives of patients with chronic pain, a 3.8% rate of opioid addiction is a small risk compared with the alternative of continuous pain and suffering."
J Pain 2007;8:573-582.
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