Potential Misuse and Inappropriate Prescription Practices Involving Opioid Analgesics | Page 3
Published Online: August 12, 2013
Ying Liu, PhD; Joseph E. Logan, PhD; Leonard J. Paulozzi, MD, MPH; Kun Zhang, MS; and Christopher M. Jones, PharmD
Roughly one-fifth of opioid prescriptions overlapped with other opioid prescriptions, and 15.1% overlapped with a benzodiazepine prescription (Table 5). Opioid prescriptions written for female versus male recipients were significantly more likely to overlap with 1 or more benzodiazepine prescriptions (17.1% vs 12.4%; P <.05). Among LA/ER opioid prescriptions, nearly a quarter overlapped with other LA/ER opioid prescriptions; more than 6% of LA/ER prescriptions were written for acute pain conditions; and 2.6% were obtained by opioid-naïve patients.
In 2009, more than 11 million opioid prescriptions were written for 3.4 million (or 19.1%) of the 17.8 million adults without cancer diagnoses, with continuous enrollment, and with at least 1 outpatient drug claim in the MarketScan Commercial Claims and Encounters databases. Most patients obtained single-opioid prescriptions without also getting prescriptions for benzodiazepines. Although more patients were treated for acute pain, more prescriptions were written for chronic pain. The majority of prescriptions were written for fewer than 30 days, and the average prescription provided roughly 60 MMEs per day. There were signs of potential opioid misuse by patients or providers among the study population: nearly a quarter of patients had at least 1 indicator of potential misuse of opioids and more than 5% had 2 or more indicators of potential misuse.
Patients with misuse indicators probably account for a disproportionate share of adverse outcomes associated with opioid use. Increased numbers of opioid prescriptions, overlapping or early refill prescriptions, dose escalation, and more days of supply of opioids have all been associated with increased risk of clinically recognized abuse.7,8 Higher daily dose has been associated with misuse and overdoses.6,7,21 Opioid dependence has been associated with concurrent opioid and psychotropic drug use.22 Simultaneous prescribing of opioids and benzodiazepines, although it might be appropriate in some cases, has been associated with multiple-provider episodes, also known as doctor shopping.23 Acute pain is not an indication for an LA/ER opioid, and such use is considered inappropriate by clinical guidelines.19,24 Many LA/ER opioids carry warnings against initiation among opioidnaïve patients.25
Other patterns in prescribing for specific types of pain have not been previously flagged as indicators of possible misuse but run counter to the recommendations of some advisory groups.For example, the New York City Department of Health has recommended no more than a 7-day supply for acute pain.24 However, in this study 22.8% of opioid prescriptions for acute pain were for 10 or more days, and 9.5% were for 30 or more days. The American College of Occupational and Environmental Medicine practice guidelines only recommend opioids on a limited basis for treatment of severe, acute low back pain, with treatment to last no more than 2 weeks.20 In this study, 42.3% of opioid prescriptions for back pain were for 30 days or more, clearly much more than recommended.
Comparisons of our findings with the published literature were difficult because of use of different indicators or different study populations. In 1 managed care population with chronic noncancer pain during 1999 through 2005, 3.5% of personyears of opioid use were at dosages of 100 MME or more,7 and in a population of veterans with chronic pain during 2008, 3.4% of those treated with opioids were at dosages of 180 MME or more.26 This compares with 14.0% of prescriptions for chronic pain over 100 MME and 4.5% over 200 MME in this study. In Massachusetts in 2006, 6.9% of patients treated with Schedule II drugs had early refills,27 compared with 7.8% for any opioid overlap in this study.
Our study is consistent with previous literature in finding that women constitute the majority of users of opioids both alone and in combination with benzodiazepines.15,28 However, the number of opioid prescriptions and days of supply received per person per year were comparable between female and male opioid recipients. Despite the fact that men are more likely to use prescription painkillers nonmedically and to abuse opioids,4,8 indicators of possible misuse were not more prevalent among male opioid recipients in our study population. This might indicate that men misusing opioid analgesics are less likely to be commercially insured, or it might reflect changes in the demographics of the problem. Alternatively, the measures used here might reflect prescribing practices more than underlying patterns of patient misuse.
Our study has several limitations. The potential misuse indicators were based on expert panels and validated by their association with misuse or abuse in other studies. In some cases, of course, such behaviors represent appropriate care for patients (eg, overlapping prescriptions resulting from changes in dosage or in drug type as a result of some adverse effect, legitimate early refills due to schedules, high daily dosagesin palliative care situations). Claims data were designed to support financial transactions rather than to capture clinical information. Pharmacy claims represent filled prescriptions reimbursed by health insurance rather than actual drug consumption. Due to large numbers of missing values for pharmacy ID and physician ID variables, we were not able to calculate doctor-shopping or pharmacy-shopping indicators, which are often considered strong indicators of opioid misuse.11,12 Lastly, reliance on ICD-9-CM codes to determine the reason for a prescription is subject to error. Many conditions are painful but are not usually counted among common causes of pain. Type of pain might also have been misclassified. Despite these limitations, our analysis represents a first comprehensive look at opioid use and potential misuse in the largest fully integrated commercial claims database in the United States.
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