Effect of Mobile Device-Assisted N-of-1 Trial Participation on Analgesic Prescribing for Chronic Pain: Randomized Controlled Trial.

OBJECTIVES: Opioids and non-steroidal anti-inflammatory drugs (NSAIDs) are frequently prescribed for chronic musculoskeletal pain, despite limited evidence of effectiveness and well-documented adverse effects. We assessed the effects of participating in a structured, personalized self-experiment ("N-of-1 trial") on analgesic prescribing in patients with chronic musculoskeletal pain. METHODS: We randomized 215 patients with chronic pain to participate in an N-of-1 trial facilitated by a mobile health app or to receive usual care. Medical records of participating patients were reviewed at enrollment and 6 months later to assess analgesic prescribing. We established thresholds of ≥ 50, ≥ 20, and > 0 morphine milligram equivalents (MMEs) per day to capture patients taking relatively high doses only, patients taking low-moderate as well as relatively high doses, and patients taking any dose of opioids, respectively. RESULTS: There was no significant difference between the N-of-1 and control groups in the percentage of patients prescribed any opioids (relative odds ratio (ROR) = 1.05; 95% confidence interval [CI] = 0.61 to 1.80, p = 0.87). There was a clinically substantial but statistically not significant reduction of the percentage of patients receiving ≥ 20 MME (ROR = 0.58; 95% CI = 0.33 to 1.04, p = 0.07) and also in the percentage receiving ≥ 50 MME (ROR = 0.50; 95% CI = 0.19 to 1.34, p = 0.17). There was a significant reduction in the proportion of patients in the N-of-1 group prescribed NSAIDs compared with control (relative odds ratio = 0.53; 95% CI = 0.29 to 0.96, p = 0.04), with no concomitant increase in average pain intensity. There was no significant change in use of adjunctive medications (acetaminophen, gabapentenoids, or topicals). DISCUSSION: These exploratory results suggest that participation in N-of-1 trials may reduce long-term use of NSAIDs; there is also a weak signal for an effect on use of opioids. Additional research is needed to confirm these results and elucidate possible mechanisms. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02116621.

Effect of Mobile Device-Supported Single-Patient Multi-crossover Trials on Treatment of Chronic Musculoskeletal Pain: A Randomized Clinical Trial.

Importance: Individually designed single-patient multi-crossover (n-of-1) trials can facilitate tailoring of treatments directed at various conditions, including chronic musculoskeletal pain (CMSP) but are potentially burdensome, which may limit uptake in research and practice. Objectives: To determine whether patients randomized to participate in an n-of-1 trial supported by a mobile health (mHealth) app would experience less pain and improved global health, adherence, satisfaction, and shared decision making compared with patients assigned to usual care. Design, Setting, and Participants: This randomized clinical trial compared participation in an individualized, mHealth-supported n-of-1 trial vs usual care. The participating 215 patients had CMSP for at least 6 weeks, had a smartphone or tablet with a data plan, were enrolled in northern California from July 2014 through July 2016, and were followed for up to 1 year by 48 clinicians in academic, community, Veterans Affairs, and military settings. Interventions: Intervention patients met with their clinicians and used a desktop interface to select treatments and trial parameters for an n-of-1 trial comparing 2 pain-management regimens. The mHealth app provided reminders to take designated treatments on assigned days and to upload responses to daily questions on pain and treatment-associated adverse effects. Control patients received care as usual. Main Outcomes and Measures: The primary outcome was change in the PROMIS (Patient-Reported Outcomes Measurement Information System) pain-related interference 8-item short-form scale (full scale range, 41-78) from baseline to 6 months. Secondary outcomes included patient-reported pain intensity, overall health, analgesic adherence, trust in clinician, satisfaction with care, medication-related shared decision making, and, for the n-of-1 group only, participant engagement and experience. Results: Among 215 patients (108 randomized to the n-of-1 intervention and 107 to control), 102 (47%) were women, and the mean (SD) age was 55.5 (11.1) years. At the 6-month follow-up, pain interference was reduced in both groups, though there was no difference between the intervention and control groups (-1.36 points; 95% CI, -2.91 to 0.19 points; P = .09). There were no advantages in secondary outcomes for intervention patients vs control patients except for higher medication-related shared decision making at 6 months (between-group difference, 11.9 points; 95% CI, 2.6-21.2 points; P = .01). Among patients assigned to the n-of-1 group, 88% (n = 86) affirmed that the mHealth app could help people like them manage their pain. Conclusions and Relevance: In this population of patients with CMSP, mHealth-supported n-of-1 trials were feasible and associated with a satisfactory user experience, but n-of-1 trial participation did not significantly improve pain interference at 6 months vs usual care. Trial Registration: ClinicalTrials.gov identifier: NCT02116621.

Factors Associated with Opioid Dose Increases: A Chart Review of Patients' First Year on Long-Term Opioids.

Objective: To examine encounter-level factors associated with opioid dose increases during patients' first year on opioid therapy for chronic pain. Design: Case-control study analyzing all opioid prescriptions for patients with chronic pain during their first year after opioid initiation. Cases were patients who experienced an overall dose escalation of ≥ 30 mg morphine equivalents over the 1-year period; controls did not experience overall dose escalation. Main measures were encounter type, opioid dose change, documented prescribing rationale, documentation of guideline-concordant opioid-prescribing practices. Two coders reviewed all encounters associated with opioid prescriptions. Analysis of factors associated with dose increases and provider documentation of prescribing rationale was conducted using multiple logistic regression. Results: There were 674 encounters coded for 66 patients (22 cases, 44 controls). Fifty-three percent of opioid prescriptions were associated with telephone encounters; 13% were associated with e-mail encounters. No prescribing rationale was documented for 43% of all opioid prescriptions and 25% of dose increases. Likelihood of dose increase and documentation of prescribing rationale did not significantly differ for cases versus controls. Compared with face-to-face encounters, dose increases were significantly less likely for telephone (OR 0.18, 95% CI 0.11-0.28) and e-mail (OR 0.23, 95% CI 0.12-0.47) encounters; documentation of prescribing rationale was significantly more likely for e-mail (OR 5.06, 95% CI 1.87-13.72) and less likely for telephone (OR 0.30, 95% CI 0.18-0.51) encounters. Conclusion: Most opioid prescriptions were written without face-to-face encounters. One quarter of dose increases contained no documented prescribing rationale. Documented encounter-level factors were not significantly associated with overall opioid dose escalation.

A preliminary evaluation of the relationship of cannabinoid blood concentrations with the analgesic response to vaporized cannabis.

A randomized, placebo-controlled crossover trial utilizing vaporized cannabis containing placebo and 6.7% and 2.9% delta-9-tetrahydrocannabinol (THC) was performed in 42 subjects with central neuropathic pain related to spinal cord injury and disease. Subjects received two administrations of the study medication in a 4-hour interval. Blood samples for pharmacokinetic evaluation were collected, and pain assessment tests were performed immediately after the second administration and 3 hours later. Pharmacokinetic data, although limited, were consistent with literature reports, namely dose-dependent increase in systemic exposure followed by rapid disappearance of THC. Dose-dependent improvement in pain score was evident across all pain scale elements. Using mixed model regression, an evaluation of the relationship between plasma concentrations of selected cannabinoids and percent change in items from the Neuropathic Pain Scale was conducted. Changes in the concentration of THC and its nonpsychotropic metabolite, 11-nor-9-carboxy-THC, were related to percent change from baseline of several descriptors (eg, itching, burning, and deep pain). However, given the large number of multiple comparisons, false-discovery-rate-adjusted P-values were not significant. Plans for future work are outlined to explore the relationship of plasma concentrations with the analgesic response to different cannabinoids. Such an appraisal of descriptors might contribute to the identification of distinct pathophysiologic mechanisms and, ultimately, the development of mechanism-based treatment approaches for neuropathic pain, a condition that remains difficult to treat.

An Exploratory Human Laboratory Experiment Evaluating Vaporized Cannabis in the Treatment of Neuropathic Pain From Spinal Cord Injury and Disease.

UNLABELLED: Using 8-hour human laboratory experiments, we evaluated the analgesic efficacy of vaporized cannabis in patients with neuropathic pain related to injury or disease of the spinal cord, most of whom were experiencing pain despite traditional treatment. After obtaining baseline data, 42 participants underwent a standardized procedure for inhaling 4 puffs of vaporized cannabis containing either placebo, 2.9%, or 6.7% delta 9-THC on 3 separate occasions. A second dosing occurred 3 hours later; participants chose to inhale 4 to 8 puffs. This flexible dosing was used to attempt to reduce the placebo effect. Using an 11-point numerical pain intensity rating scale as the primary outcome, a mixed effects linear regression model showed a significant analgesic response for vaporized cannabis. When subjective and psychoactive side effects (eg, good drug effect, feeling high, etc) were added as covariates to the model, the reduction in pain intensity remained significant above and beyond any effect of these measures (all P < .0004). Psychoactive and subjective effects were dose-dependent. Measurement of neuropsychological performance proved challenging because of various disabilities in the population studied. Because the 2 active doses did not significantly differ from each other in terms of analgesic potency, the lower dose appears to offer the best risk-benefit ratio in patients with neuropathic pain associated with injury or disease of the spinal cord. PERSPECTIVE: A crossover, randomized, placebo-controlled human laboratory experiment involving administration of vaporized cannabis was performed in patients with neuropathic pain related to spinal cord injury and disease. This study supports consideration of future research that would include longer duration studies over weeks to months to evaluate the efficacy of medicinal cannabis in patients with central neuropathic pain.

Maintenance of Blinding in Clinical Trials and the Implications for Studying Analgesia Using Cannabinoids.

The design of analgesic clinical trials invariably involves a comparison between placebo and active study medication. An assumption is made that treatment effects can be approximated by subtracting the response to placebo from that attained with the use of active study medication. However, the psychoactivity of cannabinoids may unmask their presence and lead to an expectation and/or conditioning of pain relief. For example, study participants biased toward the belief that cannabis is beneficial for their condition might be more inclined to report positive effects if they were to accurately identify the active treatment because of its psychoactivity. This may lead to incorrect assumptions regarding the efficacy of a cannabinoid. Methodologies designed to counteract unmasking need to be implemented in the design phase of a study. During the clinical trial, it is also important to query participants as to which treatment they believe they have received. Blinding can be considered to be preserved when the accuracy of treatment guesses is not considerably different than random guessing, which is estimated to be correct 50% of the time. After a study has been completed, the use of statistical methodologies such as regression and mediation analysis are worthy of consideration to see whether psychoactive effects biased the results.

Inhaled Cannabis for Chronic Neuropathic Pain: A Meta-analysis of Individual Patient Data.

UNLABELLED: Chronic neuropathic pain, the most frequent condition affecting the peripheral nervous system, remains underdiagnosed and difficult to treat. Inhaled cannabis may alleviate chronic neuropathic pain. Our objective was to synthesize the evidence on the use of inhaled cannabis for chronic neuropathic pain. We performed a systematic review and a meta-analysis of individual patient data. We registered our protocol with PROSPERO CRD42011001182. We searched in Cochrane Central, PubMed, EMBASE, and AMED. We considered all randomized controlled trials investigating chronic painful neuropathy and comparing inhaled cannabis with placebo. We pooled treatment effects following a hierarchical random-effects Bayesian responder model for the population-averaged subject-specific effect. Our evidence synthesis of individual patient data from 178 participants with 405 observed responses in 5 randomized controlled trials following patients for days to weeks provides evidence that inhaled cannabis results in short-term reductions in chronic neuropathic pain for 1 in every 5 to 6 patients treated (number needed to treat = 5.6 with a Bayesian 95% credible interval ranging between 3.4 and 14). Our inferences were insensitive to model assumptions, priors, and parameter choices. We caution that the small number of studies and participants, the short follow-up, shortcomings in allocation concealment, and considerable attrition limit the conclusions that can be drawn from the review. The Bayes factor is 332, corresponding to a posterior probability of effect of 99.7%. PERSPECTIVE: This novel Bayesian meta-analysis of individual patient data from 5 randomized trials suggests that inhaled cannabis may provide short-term relief for 1 in 5 to 6 patients with neuropathic pain. Pragmatic trials are needed to evaluate the long-term benefits and risks of this treatment.

The PREEMPT study - evaluating smartphone-assisted n-of-1 trials in patients with chronic pain: study protocol for a randomized controlled trial.

BACKGROUND: Chronic pain is prevalent, costly, and clinically vexatious. Clinicians typically use a trial-and-error approach to treatment selection. Repeated crossover trials in a single patient (n-of-1 trials) may provide greater therapeutic precision. N-of-1 trials are the most direct way to estimate individual treatment effects and are useful in comparing the effectiveness and toxicity of different analgesic regimens. The goal of the PREEMPT study is to test the 'Trialist' mobile health smartphone app, which has been developed to make n-of-1 trials easier to accomplish, and to provide patients and clinicians with tools for individualizing treatments for chronic pain. METHODS/DESIGN: A randomized controlled trial is being conducted to test the feasibility and effectiveness of the Trialist app. A total of 244 participants will be randomized to either the Trialist app intervention group (122 patients) or a usual care control group (122 patients). Patients assigned to the Trialist app will work with their clinicians to set up an n-of-1 trial comparing two pain regimens, selected from a menu of flexible options. The Trialist app provides treatment reminders and collects data entered daily by the patient on pain levels and treatment side effects. Upon completion of the n-of-1 trial, patients review results with their clinicians and develop a long-term treatment plan. The primary study outcome (comparing Trialist to usual care patients) is pain-related interference with daily functioning at 26 weeks. DISCUSSION: Trialist will allow patients and clinicians to conduct personalized n-of-1 trials. In prior studies, n-of-1 trials have been shown to encourage greater patient involvement with care, which has in turn been associated with better health outcomes. mHealth technology implemented using smartphones may offer an efficient means of facilitating n-of-1 trials so that more patients can benefit from this approach. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02116621 , first registered 15 April 2014.

Defining risk of prescription opioid overdose: pharmacy shopping and overlapping prescriptions among long-term opioid users in medicaid.

UNLABELLED: Use of multiple pharmacies concurrently (pharmacy shopping) and overlapping prescriptions may be indicators of potential misuse or abuse of prescription opioid medications. To evaluate strategies for identifying patients at high risk, we first compared different definitions of pharmacy shopping and then added the indicator of overlapping opioid prescriptions. We identified a cohort of 90,010 Medicaid enrollees who used ≥ 3 opioid prescriptions for ≥ 90 days during 2008 to 2010 from a multistate Medicaid claims database. We compared the diagnostic odds ratios for opioid overdose events of 9 pharmacy shopping definitions. Within a 90-day interval, a threshold of 4 pharmacies had the highest diagnostic odds ratio and was used to define pharmacy shopping. The overdose rate was higher in the subgroup with overlapping prescriptions (18.5 per 1,000 person-years [PYs]) than in the subgroup with pharmacy shopping as the sole indicator (10.7 per 1,000 PYs). Among the subgroup with both conditions, the overdose rate was 26.3 per 1,000 PYs, compared with 4.3 per 1,000 PYs for those with neither condition. Overlapping opioid prescriptions and pharmacy shopping measures had adjusted hazard ratios of 3.0 and 1.8, respectively, for opioid overdose. Using these measures will improve accurate identification of patients at highest risk of opioid overdose, the first step in implementing targeted prevention policies. PERSPECTIVE: Long-term prescription opioid use may lead to adverse events, including overdose. Both pharmacy shopping and overlapping opioid prescriptions are associated with adverse outcomes. This study demonstrates that using both indicators will better identify those at high risk of overdose.

Dose escalation during the first year of long-term opioid therapy for chronic pain.

OBJECTIVE: To identify patient factors and health care utilization patterns associated with dose escalation during the first year of long-term opioid therapy for chronic pain. DESIGN: Retrospective cohort study using electronic health record data. SETTING: University health system. SUBJECTS: Opioid naïve adults with musculoskeletal pain who received a new outpatient opioid prescription between July 1, 2011 and June 30, 2012 and stayed on opioids for 1 year. METHODS: Mixed-effects regression was used to estimate patients' rate of opioid dose escalation. Demographics, clinical characteristics, and health care utilization for patients with and without dose escalation were compared. RESULTS: Twenty-three (9%) of 246 patients in the final cohort experienced dose escalation (defined as an increase in mean daily opioid dose of ≥30-mg morphine equivalents over 1 year). Compared with patients without dose escalation, patients with escalation had higher rates of substance use diagnoses (17% vs 1%, P = 0.01) and more total outpatient encounters (51 vs 35, P = 0.002) over 1 year. Differences in outpatient encounters were largely due to more non face-to-face encounters (e.g., telephone calls, emails) among patients with dose escalation. Differences in age, race, concurrent benzodiazepine use, and mental health diagnoses between patients with and without dose escalation were not statistically significant. Primary care clinicians prescribed 89% of opioid prescriptions. CONCLUSIONS: Dose escalation during the first year of long-term opioid therapy is associated with higher rates of substance use disorders and more frequent outpatient encounters, especially non face-to-face encounters.

The Medicinal Cannabis Treatment Agreement: Providing Information to Chronic Pain Patients Through a Written Document.

AIM: Pain practitioners would seem to have an obligation to understand and inform their patients on key issues of the evidence base on cannabinoid therapeutics. One way to fulfill this obligation might be to borrow from concepts developed in the prescription of opioids: the use of a written agreement to describe and minimize risks. Regrettably, the widespread adoption of opioids was undertaken while harmful effects were minimized; obviously, no one wants to repeat this misstep. OBJECTIVE: This article describes a method of educating patients in a manner analogous to other treatment agreements. BACKGROUND: Surveys have demonstrated that pain is the most common indication for medical use of cannabis. As more individuals gain access to this botanical product through state ballot initiatives and legislative mandate, the pain specialist is likely to be confronted by patients either seeking such treatment where permitted, or otherwise inquiring about its potential benefits and harms, and alternative pharmaceuticals containing cannabinoids. METHODS: PubMed searches were conducted using the following keywords: cannabis guidelines, harmful effects of cannabis, medical marijuana, medicinal cannabis, opioid cannabis interaction, cannabis dependence and cannabis abuse RESULTS: : The authors selected individual tenets a medicinal cannabis patient would be asked to review and acknowledge via signature. CONCLUSIONS: Undoubtedly, the knowledge base concerning risks will be an iterative process as we learn more about the long-term use of medicinal cannabis. But we should start the process now so that patients may be instructed about our current conception of what the use of medicinal cannabis entails.

Increasing trends in Schedule II opioid use and doctor shopping during 1999-2007 in California.

PURPOSE: To examine the age and gender-specific trends of Schedule II opioid use among California residents, with special reference to multiple provider users (doctor shoppers). METHODS: Utilizing data from the California Prescription Drug Monitoring Program, we examined age and gender-specific trends of Schedule II opioid use during calendar years 1999-2007. Specifically, we analyzed the following: (1) the prevalence of Schedule II opioid users among California's population and (2) the proportion of these opioid users who were doctor shoppers (defined as an individual who used more than five different prescribers for all Schedule II opioids he or she obtained in a calendar year). RESULTS: Among all age and gender groups, the prevalence of Schedule II opioid users in California increased by 150%-280% and the prevalence of doctor shoppers among users increased by 111%-213% over 9 years. The prevalence of opioid users was lowest among 18-44 year old men (1.25%) and highest among 65-year and older women (5.31%) by 2007. The prevalence of doctor shoppers was approximately 1.4% among those up to age 64 years and 0.5% among those 65 years and older. The gender difference in doctor shoppers among all age groups was negligible. On average, the cumulative morphine-equivalent amount of Schedule II opioid per individual obtained per year was threefold to sixfold higher for doctor shoppers than for the general population across different age and gender groups. CONCLUSIONS: Age and gender differences in opioid use were relatively small, whereas the trends for use of opioids and multiple providers grew at a disquieting rate.

Age, gender, and earlier opioid requirement associations with the rate of dose escalation in long-term opioid therapy.

OBJECTIVES: To examine the association of risk factors, age, gender, and earlier opioid requirement with the rate of dose escalation in long-term opioid therapy. METHODS: This is a retrospective cohort study of 1,922 individuals identified from California's prescription drug monitoring program database who continuously used opioids from 1999 to 2007. A linear mixed-effects model was used to examine the association of age, gender, and baseline dose requirement with the rate of subsequent opioid dose change. Because of different reporting requirements before and after January 1, 2005, the analyses were conducted separately for patients' opioid use in two periods (6 years between 1999 and 2004 and 3 years between 2005 and 2007). RESULTS: Both the 6-year and the 3-year data showed a significant age association, with younger patients having a higher rate of dose escalation than older patients (p = 0.021 and <0.0001, respectively). Females had a lower rate of dose escalation than males, although the result did not achieve statistical significance in the 6-year data (p = 0.165 and 0.013, respectively). The higher the dose requirement a patient had at baseline, the lower the rate of dose escalation (p < 0.0001 in both periods). CONCLUSIONS: Age, gender, and earlier dose requirement were associated with the rate of dose change in 9-year long-term opioid therapy. Patients aged 75-100 years, being female or having large dose requirement at an earlier stage of therapy may experience a slower dose escalation or even dose decline.

Low-dose vaporized cannabis significantly improves neuropathic pain.

UNLABELLED: We conducted a double-blind, placebo-controlled, crossover study evaluating the analgesic efficacy of vaporized cannabis in subjects, the majority of whom were experiencing neuropathic pain despite traditional treatment. Thirty-nine patients with central and peripheral neuropathic pain underwent a standardized procedure for inhaling medium-dose (3.53%), low-dose (1.29%), or placebo cannabis with the primary outcome being visual analog scale pain intensity. Psychoactive side effects and neuropsychological performance were also evaluated. Mixed-effects regression models demonstrated an analgesic response to vaporized cannabis. There was no significant difference between the 2 active dose groups' results (P > .7). The number needed to treat (NNT) to achieve 30% pain reduction was 3.2 for placebo versus low-dose, 2.9 for placebo versus medium-dose, and 25 for medium- versus low-dose. As these NNTs are comparable to those of traditional neuropathic pain medications, cannabis has analgesic efficacy with the low dose being as effective a pain reliever as the medium dose. Psychoactive effects were minimal and well tolerated, and neuropsychological effects were of limited duration and readily reversible within 1 to 2 hours. Vaporized cannabis, even at low doses, may present an effective option for patients with treatment-resistant neuropathic pain. PERSPECTIVE: The analgesia obtained from a low dose of delta-9-tetrahydrocannabinol (1.29%) in patients, most of whom were experiencing neuropathic pain despite conventional treatments, is a clinically significant outcome. In general, the effect sizes on cognitive testing were consistent with this minimal dose. As a result, one might not anticipate a significant impact on daily functioning.

Individual and county-level factors associated with use of multiple prescribers and multiple pharmacies to obtain opioid prescriptions in California.

Use of multiple prescribers and pharmacies is a means by which some individuals misuse opioids. Community characteristics may be important determinants of the likelihood of this phenomenon independent of individual-level factors. This was a retrospective cohort study with individual-level data derived from California's statewide prescription drug monitoring program (PDMP) and county-level socioeconomic status (SES) data derived from the United States Census. Zero-truncated negative binomial (ZTNB) regression was used to model the association of individual factors (age, gender, drug schedule and drug dose type) and county SES factors (ethnicity, adult educational attainment, median household income, and physician availability) with the number of prescribers and the number of pharmacies that an individual used during a single year (2006). The incidence rates of new prescriber use and new pharmacy use for opioid prescriptions declined across increasing age groups. Males had a lower incidence rate of new prescriber use and new pharmacy use than females. The total number of licensed physicians and surgeons in a county was positively, linearly, and independently associated with the number of prescribers and pharmacies that individuals used for prescription opioids. In summary, younger age, female gender, and living in counties with more licensed physicians and surgeons were associated with use of more prescribers and/or more pharmacies for obtaining prescription opioids.

Medical marijuana: clearing away the smoke.

Recent advances in understanding of the mode of action of tetrahydrocannabinol and related cannabinoid in-gredients of marijuana, plus the accumulating anecdotal reports on potential medical benefits have spurred increasing re-search into possible medicinal uses of cannabis. Recent clinical trials with smoked and vaporized marijuana, as well as other botanical extracts indicate the likelihood that the cannabinoids can be useful in the management of neuropathic pain, spasticity due to multiple sclerosis, and possibly other indications. As with all medications, benefits and risks need to be weighed in recommending cannabis to patients. We present an algorithm that may be useful to physicians in determining whether cannabis might be recommended as a treatment in jurisdictions where such use is permitted.

Time series analysis of California's prescription monitoring program: impact on prescribing and multiple provider episodes.

UNLABELLED: Prescription monitoring programs (PMPs) are designed to reduce medication diversion by identifying individuals obtaining the same medication from multiple providers (termed multiple provider episodes [MPEs]). This study determined whether recent changes to California's PMP influenced: 1) the extent that practitioners issue prescriptions for a variety of Schedule II opioids; and 2) the incidence of MPEs involving these opioids. Intervention time series of California's PMP data was used to determine the effect of requiring practitioners to transition from using triplicate prescription forms for Schedule II medications to security forms for all controlled substances. Outcome measures included changes in number of prescriptions issued for Schedule II long-acting or short-acting (SA) opioids and the MPEs involving these medications. Requiring a security form was associated with a sustained prescribing increase for SA hydromorphone, meperidine, and SA oxycodone; no prescribing changes were found for SA fentanyl, methadone, and SA morphine, or for any long-acting opioids. The same policy change, however, increased MPEs involving all opioids. Further effort is required to determine how California's PMP can continue to ensure availability of prescription opioids for medical use while better mitigating their diversion. PERSPECTIVE: Statistical model-building was used to evaluate the influence of changes to California's prescription monitoring program. The extent that practitioners prescribe Schedule II opioids and the incidence of people receiving prescriptions from multiple providers were measured. Such research illustrates the viability of evaluating drug control program impact on prescribing practice and potential diversion behaviors.

An analysis of the number of multiple prescribers for opioids utilizing data from the California Prescription Monitoring Program.

BACKGROUND: Prescription monitoring programs scrutinize the prescribing of controlled substances to diminish the utilization of multiple prescribers (aka. "doctor shopping"). The use of multiple prescribers is not a problem per se and can be legitimate, as when the patient's regular physician is not available or a concurrent painful condition is being cared for by a different practitioner. PURPOSE: The primary objective of this study was to determine if those patients who used a few prescribers (two to five) in a 1-year period were distinguishable from those who used only one prescriber. METHODS: We performed a secondary data analysis of the California Prescription Monitoring Program, the Controlled Substance Utilization Review and Evaluation System, by using data collected during 1999-2007. RESULTS: The group who used a few providers (two to five) differed substantially from those who visited one provider over a 1-year period. However, the dissimilarity did not suggest that these patients were more prone to the abuse of opioids. CONCLUSIONS: The decision not to investigate patients who visit a low number of multiple prescribers (two to five) appears to be justifiable. If the number of providers in a given period of time is used to determine if a patient should be challenged as being a "doctor shopper," cutoffs with high specificity (low false-positive rates) should be chosen. Further epidemiologic research is needed to determine the association of the number of prescribers and misuse and/or abuse of opioids.