SAN DIEGO – A new study of medical records offers insights into the persistence of opioid use: Most patients who were prescribed opioid painkillers did not go back for a refill right away, but nearly half of patients who stopped taking the drugs for at least 6 months ended up using them again over a 3-year period.
“This key finding indicates that programs that address opioid use need to focus on long-term support and education to ensure that individuals do not become long-term users,” psychiatrist and lead author Shareh Ghani, MD, vice president and medical director of Magellan Health Services, San Francisco, said in an interview.
Researchers also found that opioid use appeared linked to three unexpected conditions – lipid disorders, hypertension, and sleep-wake disorders – and found that more than half of those who had at least two prescriptions for high-dose opioids kept taking the drugs over 18 months after an initial 90-day period.
Dr. Ghani and his colleague, Gowri Shetty, MPH, analyzed medical and pharmacy data from 2009-2012 for 2.5 million people. The participants, aged 20-64 years, came from across the United States and were part of a commercial health plan.
The researchers found that 21% had received one prescription for an opioid. Users considered at risk for persistent use – more than one prescription over 3 years – were more likely than were nonusers to have these characteristics: spondylosis and other back problems (odds ratio, 5.3), substance-related and addictive disorders (OR, 4.6), sleep-wake disorders (OR, 2.2), depressive disorders (OR, 1.7), headaches (OR, 2.1), and anxiety disorders (OR, 1.5.) The P values for all of those characteristics were less than .001.
They also found that patients who received certain kinds of treatment were at higher risk, compared with nonusers: those who were treated for substance abuse treatment (OR, 4.5), in emergency departments (OR, 3.2), with anesthesia (OR, 4.2), for mental health issues (OR, 2.3), and with surgery (OR, 2.0). The P values for all of those characteristics also were less than .001.
“The unexpected findings were the presence of lipid disorders, hypertension, and sleep-wake disorders. These diagnoses were not found in other literature,” Dr. Ghani said in an interview. “These conditions, however, are related to others that are known. For instance, a person with knee joint pain who is overweight – a known risk factor – may also have hypertension and lipid disorders.”
The researchers also discovered that 80% of patients who received an opioid prescription did not get a refill. Of those who had at least two prescriptions and a stable dose over an initial 90 days, 14% went on to have more prescriptions and a boost in dosage over 18 months, while 12% stayed the same and almost 74% took less.
But the situation was different for those with at least two prescriptions and a high dose (more than 120 mg) over an initial 90 days: 56% of them stayed at that level over 18 months.
The researchers also found that 48% of those who had stopped using opioids for at least 6 months went on to use them again. This high rate “suggests that physicians and patients need to be aware of the high risk of dependence and addiction for some individuals,” Dr. Ghani said. “Studying prescription fill behaviors and the persistence of prescription opioid users helps identify individuals at high risk for persistent use and may provide a better understanding of how to target interventions for inappropriate opioid use.”
The study has limitations. It does not indicate whether patients became substance abusers, nor does it provide details about opioids obtained illegally. Still, “we do know from literature and clinical experience that staying on prescription opioids may lead to dependence, escalation of dose, and increased risk of developing addictions that can lead to using street drugs like heroin,” Dr. Ghani said.
Magellan funded the study. Dr. Ghani reported no additional disclosures.