Implementing physics-based digital patient twins to tailor the switch of oral morphine to transdermal fentanyl patches based on patient physiology

Fentanyl transdermal patches are widely implemented for cancer-induced pain treatment due to the high potency of fentanyl and gradual drug release. However, transdermal fentanyl up-titration for opioid-naïve patients is difficult, which is why opioid treatment is often started with oral/iv morphine. Based on the daily dose of morphine, the initial dose of the fentanyl patch is decided upon. After reaching a stable level of pain, the switch is made from oral/iv morphine to transdermal fentanyl. There are standard calculation tools for transferring from oral/iv morphine to transdermal fentanyl, which is the same for all patients. By considering the variations in the physiology of the patients, a unique switching strategy cannot meet the needs of different patients. This study explores the outcome in terms of pain relief and minute ventilation during opioid therapy. For this, we used physics-based simulations on a virtually-generated population of patients, and we applied the same therapy to all patients. We could show that patients' physiology, such as gender, age, and weight, greatly impact the outcome of the therapy; as such, the correlation coefficient between pain intensity and age is 0.89, and the correlation coefficient between patient's weight and maximum plasma concentration of morphine and fentanyl is -0.98 and -0.97. Additionally, a different combination of the duration of overlap between morphine and fentanyl therapy with different doses of fentanyl was considered for the virtual patients to find the best opioid-switching strategy for each patient. We explored the impact of combining physiological features to determine the best-suited strategy for virtual patients. Our findings suggest that tailoring morphine and fentanyl therapy only based on a limited number of features is insufficient, and increasing the number of impactful physiological features positively influences the outcome of the therapy.

A national population-based study of cannabis use and correlates among U.S. veterans prescribed opioids in primary care

BACKGROUND

Cannabis is marketed as a treatment for pain. There is limited data on the prevalence of cannabis use and its correlates among Veterans prescribed opioids.

OBJECTIVE

To examine the prevalence and correlates of cannabis use among Veterans prescribed opioids.

DESIGN

Cross-sectional study.

PARTICIPANTS

Veterans with a urine drug test (UDT) from Primary Care 2014-2018, in 50 states, Washington, D.C., and Puerto Rico. A total of 1,182,779 patients were identified with an opioid prescription within 90 days prior to UDT.

MAIN MEASURES

Annual prevalence of cannabis positive UDT by state. We used multivariable logistic regression to assess associations of demographic factors, mental health conditions, substance use disorders, and pain diagnoses with cannabis positive UDT.

RESULTS

Annual prevalence of cannabis positive UDT ranged from 8.5% to 9.7% during the study period, and in 2018 was 18.15% in Washington, D.C. and 10 states with legalized medical and recreational cannabis, 6.1% in Puerto Rico and 25 states with legalized medical cannabis, and 4.5% in non-legal states. Younger age, male sex, being unmarried, and marginal housing were associated with use (p < 0.001). Post-traumatic stress disorder (adjusted odds ratio [AOR] 1.17; 95% confidence interval [CI] 1.13-1.22, p < 0.001), opioid use disorder (AOR 1.14; CI 1.07-1.22, p < 0.001), alcohol use disorder or positive AUDIT-C (AOR 1.34; 95% CI 1.28-1.39, p < 0.001), smoking (AOR 2.58; 95% CI 2.49-2.66, p < 0.001), and other drug use disorders (AOR 1.15; 95% CI 1.03-1.29, p = 0.02) were associated with cannabis use. Positive UDT for amphetamines AOR 1.41; 95% CI 1.26-1.58, p < 0.001), benzodiazepines (AOR 1.41; 95% CI 1.31-1.51, p < 0.001) and cocaine (AOR 2.04; 95% CI 1.75-2.36, p < 0.001) were associated with cannabis positive UDT.

CONCLUSIONS

Cannabis use among Veterans prescribed opioids varied by state and by legalization status. Veterans with PTSD and substance use disorders were more likely to have cannabis positive UDT. Opioid-prescribed Veterans using cannabis may benefit from screening for these conditions, referral to treatment, and attention to opioid safety.

Cumulative Laxation Response with Methylnaltrexone: Implications for Hospitalized Patients with Advanced Illness and Opioid-Induced Constipation

Background

Opioid-induced constipation (OIC) may increase the risk of fecal impaction and mortality in patients with advanced illness. Methylnaltrexone (MNTX) is efficacious for OIC.

Objective

The purpose of this analysis was to evaluate cumulative rescue-free laxation response with repeat MNTX dosing in patients with advanced illness who were refractory to current laxative regimens and to assess the influence, if any, of poor functional status on response to MNTX treatment.

Methods

This analysis included pooled data from patients with advanced illness and established OIC who were on a stable opioid regimen in a pivotal, randomized, placebo (PBO)-controlled clinical trial (study 302 [NCT00402038]) or a randomized, PBO-controlled Food and Drug Administration-required postmarketing study (study 4000 [NCT00672477]). Patients in study 302 received subcutaneous MNTX 0.15 mg/kg or PBO every other day, whereas those in study 4000 received MNTX 8 mg (body weight ≥38 to <62 kg), MNTX 12 mg (body weight ≥62 kg), or PBO every other day. Outcomes included cumulative rescue-free laxation rates at 4- and 24-hours postdose for the first 3 doses of study drug and time to rescue-free laxation. To assess if functional status influenced treatment outcomes, we performed a secondary analysis on the outcomes stratified by baseline World Health Organization/Eastern Cooperative Oncology Group performance status, pain scores, and safety.

Results

One hundred eighty-five patients received PBO and 179 patients received MNTX. The median age was 66.0 years, 51.5% were women, 56.5% had a baseline World Health Organization/Eastern Cooperative Oncology Group performance status score >2, and 63.4% had a primary diagnosis of cancer. Cumulative rescue-free laxation rates were significantly higher with MNTX than PBO 4- and 24-hours after doses 1, 2, and 3 (P < 0.0001), and between-treatment comparisons remained significant (P < 0.0001) regardless of performance status. The estimated time to first rescue-free laxation was shorter for patients receiving MNTX versus PBO. No new safety signals were identified.

Conclusions

Repeated use of MNTX represents a safe and effective treatment for OIC in patients with advanced illness regardless of baseline performance status. ClinicalTrials.gov identifier: NCT00672477. (Curr Ther Res Clin Exp. 2023; 84:XXX-XXX)© 2023 Elsevier HS Journals, Inc.

Does preoperative opioid therapy in patients with a single lumbar disc herniation positively influence the postoperative outcome detected by quantitative sensory testing?

The importance of the type of pain medication in spinal disease is an ongoing matter of debate. Recent guidelines recommend acetaminophen and NSAIDs as first-line medication for lumbar disc herniation. However, opioid pain medication is commonly used in patients with chronic pain, and therefore also in patients with sciatica. The aim of this study is to evaluate if opioids have an impact on the outcome in patients suffering from lumbar disc herniation. To assess this objectively quantitative sensory testing (QST) was applied. In total, 52 patients with a single lumbar disc herniation confirmed on magnetic resonance imaging (MRI) and treated by lumbar sequesterectomy were included in the trial. Patients were analysed according to their preoperative opioid intake: 35 patients who did not receive opioids (group NO) and 17 patients, who received opioids preoperatively (group O). Further evaluation included detailed medical history, physical examination, various questionnaires, and QST. No pre- and postoperative differences were detected in thermal or mechanical thresholds (p > 0.05). Wind-up ratio (WUR) differed significantly between groups 1 week postoperatively (p = 0.025). The NRS for low back pain was rated significantly higher in the non-opioid group (NO) after 1-week follow-up (p = 0.026). Radicular pain tended to be higher in the NO group after 12 months of follow-up (p = 0.023). Opioids seem to be a positive predictor for the postoperative pain outcome in early follow-up in patients undergoing lumbar sequesterectomy. Furthermore, patients presented with less radicular pain 1 year after surgery.

Spanish Validation of the COMM Scale to Assess the Misuse of Prescription Opioids in Patients with Chronic Noncancer Pain

The Current Opioid Misuse Measure (COMM) is a questionnaire used to identify and monitor chronic pain patients on opioid therapy who may be misusing their prescription opioids. The aim of the present study was to adapt the questionnaire for its use in Spanish-speaking populations. A total of 171 individuals (131 women and 40 men) with nononcological chronic pain participated in this cross-sectional study. The most frequent pain diagnoses in the sample were fibromyalgia, herniated disc, and rheumatoid arthritis. Systematic sampling was used. All individuals were interviewed at their clinic between March 2018 and February 2020. The dimensionality of the COMM-SV items was evaluated using an optimal implementation of parallel analysis (PA) and an exploratory factor analysis. Internal consistency, test-retest reliability, and criterion and convergent validity were calculated. The COMM-SV comprises five factors: problematic interpersonal behaviour, searching for more medication than prescribed, medication misuse and self-injurious thoughts, emergency use, and memory and attention problems. It has good reliability and adequate test-retest stability. The results support its criterion and convergent validity. Given the increasing use and abuse of opioids, a valid and reliable instrument is needed in Spanish settings to identify patients with chronic pain who present aberrant behaviour related to the use of these medications. The COMM-SV enables Spanish clinicians to do that.

Mindfulness-based therapy compared to cognitive behavioral therapy for opioid-treated chronic low back pain: Protocol for a pragmatic randomized controlled trial

OBJECTIVE

Chronic low back pain (CLBP) is disabling and costly. Existing therapies have proven suboptimal, with many patients resorting to long-term opioid therapy, which can cause harms. Cognitive behavioral (CBT) and mindfulness-based (MBT) therapies can be effective and offer unique skills for safe pain coping. This article describes the protocol for a study evaluating comparative effectiveness of CBT and MBT in adults with opioid-treated CLBP.

DESIGN

Pragmatic, multi-center randomized controlled trial (RCT).

SETTINGS

Community and outpatient care.

PARTICIPANTS

Planned enrollment of 766 adults (383/group) with CLBP treated with long-term opioids (≥3 months; ≥15 mg/day morphine-equivalent dose).

INTERVENTIONS

CBT or MBT consisting of eight weekly therapist-led, two-hour group sessions, and home practice (≥30 min/day, 6 days/week) during the 12-month study.

MAIN OUTCOME MEASURES

Main outcome measures, collected by self-report at baseline, then three, six, nine and 12 months post-entry, include co-primary measures: pain intensity (Numeric Rating Scale) and function (Oswestry Disability Index), and secondary measures: quality of life (Medical Outcomes Study) and average daily opioid dose (Timeline Followback). Baseline scores of depression, anxiety, and opioid misuse questionnaires will be assessed as potential contributors to the heterogeneity of treatment response. Intention-to-treat, linear mixed-effects analysis will examine treatment effectiveness. Qualitative data will augment the quantitative measures.

CONCLUSIONS

This will be the largest RCT comparing CBT and MBT in opioid-treated CLBP. It will provide evidence on the impact of these interventions, informing clinical decisions about optimal therapy for safe, effective care, improving quality of life and decreasing opioid-related harm among adults with refractory CLBP.

Nonopioid drug combinations for cancer pain: protocol for a systematic review

This protocol will guide a review of clinical trials that evaluate the efficacy and safety of nonopioid analgesic drug combinations for the management of cancer-related pain.

Introduction:

Pain related to cancer, and its treatment, is common, may severely impair quality of life, and imposes a burden on patients, their families and caregivers, and society. Cancer-related pain is often challenging to manage, with limitations of analgesic drugs including incomplete efficacy and dose-related adverse effects.

Objectives:

Given problems with, and limitations of, opioid use for cancer-related pain, the identification of nonopioid treatment strategies that could improve cancer pain care is an attractive concept. The hypothesis that combinations of mechanistically distinct analgesic drugs could provide superior analgesia and/or fewer adverse effects has been tested in several pain conditions, including in cancer-related pain. Here, we propose to review trials of nonopioid analgesic combinations for cancer-related pain.

Methods:

Using a predefined literature search strategy, trials—comparing the combination of 2 or more nonopioid analgesics with at least one of the combination's individual components—will be searched on the PubMed and EMBASE databases from their inception until the date the searches are run. Outcomes will include pain intensity or relief, adverse effects, and concomitant opioid consumption.

Results/Conclusions:

This review is expected to synthesize available evidence describing the efficacy and safety of nonopioid analgesic combinations for cancer-related pain. Furthermore, a review of this literature will serve to identify future research goals that would advance our knowledge in this area.

Managing Acute Dental Pain: Principles for Rational Prescribing and Alternatives to Opioid Therapy

Pharmacotherapy forms an integral part of acute dental pain management. In a majority of cases, safe and effective management of acute dental pain can be accomplished with a non-opioid medication regimen. Nonetheless, in certain circumstances use of opioid medications may be needed. Furthermore, there are various pain management regimens, such as pre-emptive analgesia, post-procedural cold compression, use of long acting anesthetic, and compound drug therapy that can improve the efficacy of analgesics to achieve a desired therapeutic response without compromising patient safety.

Development and Performance of a Web-Based Tool to Adjust Urine Toxicology Testing Frequency: Retrospective Study

BACKGROUND

Several pain management guidelines recommend regular urine drug testing (UDT) in patients who are being treated with chronic opioid analgesic therapy (COAT) to monitor compliance and improve safety. Guidelines also recommend more frequent testing in patients who are at high risk of adverse events related to COAT; however, there is no consensus on how to identify high-risk patients or on the testing frequency that should be used. Using previously described clinical risk factors for UDT results that are inconsistent with the prescribed COAT, we developed a web-based tool to adjust drug testing frequency in patients treated with COAT.

OBJECTIVE

The objective of this study was to evaluate a risk stratification tool, the UDT Randomizer, to adjust UDT frequency in patients treated with COAT.

METHODS

Patients were stratified using an algorithm based on readily available clinical risk factors into categories of presumed low, moderate, high, and high+ risk of presenting with UDT results inconsistent with the prescribed COAT. The algorithm was integrated in a website to facilitate adoption across practice sites. To test the performance of this algorithm, we performed a retrospective analysis of patients treated with COAT between June 2016 and June 2017. The primary outcome was compliance with the prescribed COAT as defined by UDT results consistent with the prescribed COAT.

RESULTS

979 drug tests (867 UDT, 88.6%; 112 oral fluid testing, 11.4%) were performed in 320 patients. An inconsistent drug test result was registered in 76/979 tests (7.8%). The incidences of inconsistent test results across the risk tool categories were 7/160 (4.4%) in the low risk category, 32/349 (9.2%) in the moderate risk category, 28/338 (8.3%) in the high risk category, and 9/132 (6.8%) in the high+ risk category. Generalized estimating equation analysis demonstrated that the moderate risk (odds ratio (OR) 2.1, 95% CI 0.9-5.0; P=.10), high risk (OR 2.0, 95% CI 0.8-5.0; P=.14), and high risk+ (OR 2.0, 95% CI 0.7-5.6; P=.20) categories were associated with a nonsignificantly increased risk of inconsistency vs the low risk category.

CONCLUSIONS

The developed tool stratified patients during individual visits into risk categories of presenting with drug testing results inconsistent with the prescribed COAT; the higher risk categories showed nonsignificantly higher risk compared to the low risk category. Further development of the tool with additional risk factors in a larger cohort may further clarify and enhance its performance.

Pain catastrophizing as a predictor of suicidal ideation in chronic pain patients with an opiate prescription

Chronic pain and opioid use are associated with increased risk for suicidal ideation and behaviors (SIB) in cross-sectional studies, particularly among individuals who catastrophize about their pain. This study examined the longitudinal association between two styles of pain coping, catastrophizing and hoping/praying, as predictors of subsequent SIB, as well as possible mediators of this association among patients with chronic pain receiving long-term opioid therapy. Participants (n = 496) were adults with chronic nonmalignant pain on long-term opioid therapy who did not develop an opioid use disorder. Participants were assessed for pain coping, suicidal ideation, depression, social support and pain interference at baseline, and were reassessed for SI, depression, and pain interference at 6- and 12-month follow-ups. Catastrophizing was a significant predictor of increased subsequent SIB, whereas hoping/praying did not protect against future SIB. The relationship between catastrophizing and future SIB was mediated by depression, but not social support or pain interference. In conclusion, catastrophizing was an important predictor of subsequent SIB due to its effect on increasing depression among patients with chronic nonmalignant pain receiving long-term opioid therapy. Future research should explore the extent to which targeting catastrophizing reduces subsequent depression and suicide risk.

Carfentanil toxicity in the African green monkey: Therapeutic efficacy of naloxone

Carfentanil is an ultra-potent opioid with an analgesic potency 10,000 times that of morphine but has received little scientific investigation. Three experiments were conducted to evaluate the toxicity of carfentanil and the efficacy of naloxone in adult male African green monkeys. The first experiment determined the ED₅₀ (found to be 0.71 μg/kg) of subcutaneous carfentanil for inducing bradypnea and/or loss of posture. Experiment 2 attempted to establish the ED₅₀ of naloxone for rapidly reversing the bradypnea/loss of posture induced by carfentanil (1.15 μg/kg). Experiment 3 evaluated the effects of carfentanil (0.575 μg/kg) alone, the safety of naloxone (71-2841 μg/kg), and the efficacy of naloxone (71-710 μg/kg) administration at two time points following carfentanil (1.15 μg/kg) on operant choice reaction time. Collectively, these experiments characterized the temporal progression of carfentanil-induced toxic signs, determined the range of naloxone doses that restored respiratory and gross behavioral function, and determined the time course and range of naloxone doses that partially or completely reversed the effects of carfentanil on operant choice reaction time performance in African green monkeys. These results have practical relevance for the selection of opioid antagonists, initial doses, and expected functional outcomes following treatment of synthetic opioid overdose in a variety of operational/emergency response contexts.

Changes in use of opioid therapy after colon cancer diagnosis: a population-based study

PURPOSE

To describe patterns of opioid use in cancer survivors.

METHODS

In a cohort study of colon cancer patients diagnosed during 1995-2014 and enrolled at two Kaiser Permanente regions, we constructed quarterly measures of opioid use from 1 year before cancer diagnosis through 5 years after diagnosis to examine changes in use. Measures included any use, incident use, regular use (use ≥ 45 days in a 91-day quarter), and average daily dose (converted to morphine milligram equivalent, MME). We also assessed temporal trends of opioid use.

RESULTS

Of 2,039 colon cancer patients, 11-15% received opioids in the four pre-diagnosis quarters, 68% in the first quarter after diagnosis, and 15-17% in each subsequent 19 quarters. Regular opioid use increased from 3 to 5% pre-diagnosis to 5-7% post diagnosis. Average dose increased from 15 to 17 MME/day pre-diagnosis to 14-22 MME/day post diagnosis (excluding the quarter in which cancer was diagnosed). Among post-diagnosis opioid users, 73-95% were on a low dose (< 20 MME/day). Over years, regular use of opioids increased in survivorship with no change in dosage.

CONCLUSION

Opioid use slightly increased following a colon cancer diagnosis, but high-dose use was rare. Research is needed to differentiate under- versus over-treatment of cancer pain.

Stopping or Decreasing Opioid Therapy in Patients on Chronic Opioid Therapy

With the rising concerns about long-term opioid use, particularly in patients with chronic noncancer pain, more and more patients are being considered for decreased doses or discontinuation of opioid therapy. This is a challenging clinical situation for both patient and clinician and should be presented in a shared decision-making model so that the patient understands the risks of opioid therapy and how the therapy will be discontinued. The patient should be aware of the long-range plan and its milestones. It is imperative that alternate pain control treatments be made available to the patient early, and that the patient never feels abandoned by the healthcare team. There can be many barriers in shared decision-making and multiple discussions between patient and provider may be required. Opioid use should not be decreased sharply or discontinued abruptly, but should be gradually decremented in a process known as tapering. Tapering should be systematic and planned in advance with the patient knowing the steps. Slow tapers (over months) are more comfortable for the patients but may not always be appropriate. There is guidance for planning the taper and the patient should be closely monitored throughout this process. If withdrawal symptoms occur, they can be managed, for example, with lofexidine. Patients should get full support as they explore new pain control options. For patients who have opioid use disorder, addiction counseling may be appropriate. Navigating opioid discontinuation can be slow work, but optimal results occur when the healthcare team works together and respectfully with the patient.

PEG vs. sennosides for opioid-induced constipation in cancer care

PURPOSE

This randomized double-blind, double-dummy, 2-treatment, 2-period crossover study aimed to compare the efficacy and tolerability of polyethylene glycol (PEG) and sennosides in ambulatory cancer patients with opioid-induced constipation.

METHODS

Outpatients ≥ 18 years old with cancer, at risk of or already experiencing opioid-induced constipation, were randomly assigned to begin a standard bowel protocol of escalating doses of sennosides or PEG, plus a dummy preparation. After 3 weeks, the patients switched to the alternate active product and dummy preparation. Constipation was assessed using the revised Victoria Bowel Performance Scale (rBPS) at the end of each of the 2 consecutive 21-day study periods for the number of days with a satisfactory bowel movement, the time in days to goal rBPS (G), and the treatment preference of each patient.

RESULTS

Seventy patients were recruited, with 42 completing their first treatment period and 28 completing both treatment periods. For the typical patient, the expected number of days with a satisfactory bowel movement per days of treatment was found to be 1.21 times higher on PEG than on sennosides in a particular period (95% credible interval 0.96 to 1.55). Patients taking PEG were 1.47 times more likely to reach a rBPS of G before patients taking sennosides in the first period (95% confidence interval 0.74 to 2.94). There was no evidence of a difference in patient preference between laxatives.

CONCLUSION

Our study found weak evidence that PEG is superior to sennosides with respect to overall effectiveness in cancer patients with opioid-induced constipation.

Impact of an innovative pain elective course on student beliefs and attitudes towards opioid medication use

BACKGROUND AND PURPOSE

To determine if an innovative elective course in chronic pain management focused on a multimodal treatment approach changed student views on opioid use for chronic, non-cancer pain.

EDUCATIONAL ACTIVITY AND SETTING

Offered to students in the second and third professional year, the course focused on various aspects of the treatment and impact of pain. Students completed two major, self-directed projects as well as four reflection journals throughout the semester. A nine question survey was provided to students on the first and last day of class that identified their beliefs and attitudes towards opioid use in chronic non-cancer pain using a five point Likert scale.

FINDINGS

There was a statistical difference in one question asking if long acting opioids were effective in controlling pain long term.

SUMMARY

There was evidence of change in student perceptions. Similar self-directed courses should be considered by other institutions as a means to change student beliefs and attitudes.

Day-to-day pain symptoms are only weakly associated with opioid craving among patients with chronic pain prescribed opioid therapy

BACKGROUND

Over the past decade, there has been a substantial rise in the use of opioids for the treatment of chronic noncancer pain. Despite the potential benefits of opioid therapy, the rise in the use of opioids has been accompanied by escalating rates of prescription opioid misuse and addiction. There is now a growing body of evidence indicating that opioid craving (i.e., the subjective desire to consume opioids) is one of the strongest determinants of opioid misuse among patients with chronic pain prescribed opioids. Although research has elucidated some of the factors associated with opioid craving, the contribution of patients' levels of pain to opioid craving remains unclear.

OBJECTIVE

The main objective of this study was to examine the day-to-day association between pain and opioid craving.

METHODS

In this longitudinal cohort study, patients with chronic pain prescribed opioid therapy completed baseline measures and were then asked to provide daily reports of pain intensity and opioid craving for a period of 14 days.

RESULTS

Multilevel analyses indicated that day-to-day elevations in patients' levels of pain were associated with heightened opioid craving. That is, on more painful days, patients reported higher levels of craving. Within-person changes in pain intensity, however, explained less than 5% of the variance in patients' reports of craving.

CONCLUSION

Findings from this study suggest that patients with chronic pain do not crave their opioid medications simply because they experience high levels of pain. The theoretical and clinical implications of our findings are discussed.

Symptoms of Depression Are Associated With Opioid Use Regardless of Pain Severity and Physical Functioning Among Treatment-Seeking Patients With Chronic Pain

Depression may be a critical factor in the initiation and maintenance of opioids. This study investigated the association among opioid use, pain, and depression in patients evaluated at a university-based outpatient pain clinic. Of the 2,104 new patients included, 55.89% reported current opioid use and showed a worse phenotypic profile (eg, higher pain severity, worse physical functioning) compared with nonopioid users. In addition, more opioid users reported symptoms suggestive of depression than those not taking opioids (43.6% vs 26.8%, P < .001). In a multivariate logistic regression model, increased pain severity was associated with increased probability of taking opioids; however, this was moderated by depression (estimate = -.212, P < .001). For nondepressed patients, the predicted probabilities of opioid use increased as pain severity increased. In contrast, among patients with symptoms of depression, the probability of taking opioids did not change based on pain severity. Similarly, although increased physical function was associated with increased probability of opioid use, this was moderated by depression (estimate = .033, P = .034). Patients with symptoms of depression were more likely to be taking opioids at higher levels of functioning (Ps < .03). Perspective: This study investigated the association among opioid use, pain, and depression at a university-based outpatient pain clinic. Depression emerged as a moderator of the relationship among opioid use, pain severity, and physical functioning. These findings lend support to the hypothesis that patients may be self-medicating affective pain with opioids.

Cancer pain and current theory for pain control

This article discusses current trends in managing cancer pain, with specific regard to opioid transmission, descending pathway inhabitation, and ways to facilitate the endogenous antinociceptive chemicals in the human body. Various techniques for opioid and nonopioid control of potential pain situations of patients with cancer are discussed. The benefits of using pharmacogenetics to assess the appropriate medications are addressed. Finally, specific treatment of abdominal cancer pain using radiofrequency lesioning is discussed.

Clinical monitoring and high-risk conditions among patients with SUD newly prescribed opioids and benzodiazepines

BACKGROUND

Opioid therapy alone or in combination with benzodiazepines poses safety concerns among patients with substance use disorders (SUD). Guidelines for opioid therapy recommend SUD treatment and enhanced monitoring, especially in patients with additional risk factors, but information on monitoring practices is sparse. This study estimated high-risk conditions - psychiatric comorbidity, suicide risk, and age <35 and ≥65 - and described clinical monitoring among patients with SUD who were newly prescribed opioids alone and concurrent with benzodiazepines long-term.

METHODS

This study included VA Northwest Veterans Network patients with SUD who started opioids only (n=980) or benzodiazepines and opioids concurrently (n=353) long-term (≥90 days) in 2009-2010. Clinical characteristics, outpatient visits and urine drug screens (UDS) documented within 7-months after starting medications were extracted from VA data.

RESULTS

Approximately 67% (95% CI: 64-70) of opioids only and 94% (92-97) of concurrent medications groups had ≥1 psychiatric diagnoses. Prevalences of suicide risk and age <35 and ≥65 were 7% (5-8), 6% (5-8) and 18% (15-20) among the opioids only group, and 20% (16-24), 8% (5-11) and 13% (9-16) among the concurrent medications group. Among patients prescribed opioids only and medications concurrently, 87% and 91% attended primary care, whereas 28% and 26% attended SUD specialty-care. Overall, 30% and 48% of opioids only and concurrent medications groups engaged in mental health or SUD care, and 35% and 39% completed UDS.

CONCLUSIONS

Improvements in clinical monitoring are needed as many VA patients with SUD and comorbid risks who initiate opioid therapy do not receive sufficient mental health/SUD care or UDS monitoring.

The missing 'P' in pain management: how the current opioid epidemic highlights the need for psychiatric services in chronic pain care

OBJECTIVE

The prevalence of opioid therapy for chronic noncancer pain has increased dramatically in recent years, with a parallel increase in opioid abuse, misuse and deaths from accidental overdose. We review epidemiological and clinical data that point to the important roles psychiatric disorders have in the use and abuse of opioids in patients with chronic pain.

METHOD

We conducted literature searches on the PubMed with the key phrases "chronic pain" and "opioid therapy" and selected those articles on the epidemiology of comorbidity between chronic pain and psychiatric disorders, the trends in long-term opioid therapy and the clinical trials that involved using opioid therapy for chronic pain or for mental health disorders. We then thoroughly reviewed the bibliography of all relevant articles to identify additional papers to be included in the present review.

RESULTS

Chronic pain is highly comorbid with common psychiatric disorders. Patients with mental health and substance abuse disorders are more likely to receive long-term opioid therapy for chronic pain and more likely to have adverse outcomes from this therapy. Although opioids may exert brief antidepressant and anxiolytic effects in some patients with depression or anxiety, there is scant evidence for long-term benefit from opioid treatment of psychiatric disorders.

CONCLUSIONS

Opioids may be used in current clinical practice as the de facto and only psychiatric treatment for patients with chronic pain, despite little evidence for sustained benefit. The opioid epidemic thus reflects a serious unmet need for better recognition and treatment of common mental health problems in patients with chronic pain. Psychiatry is the missing P in chronic pain care.