The cognitive effects of opioids in chronic non-cancer pain

Association between pain interference and motoric cognitive risk syndrome in older adults: a population-based cohort study

OBJECTIVES

Motoric cognitive risk syndrome (MCR) is a pre-dementia condition characterized by subjective complaints in cognition and slow gait. Pain interference has previously been linked with cognitive deterioration; however, its specific relationship with MCR remains unclear. We aimed to examine how pain interference is associated with concurrent and incident MCR.

METHODS

This study included older adults aged ≥ 65 years without dementia from the Health and Retirement Study. We combined participants with MCR information in 2006 and 2008 as baseline, and the participants were followed up 4 and 8 years later. The states of pain interference were divided into 3 categories: interfering pain, non-interfering pain, and no pain. Logistic regression analysis was done at baseline to examine the associations between pain interference and concurrent MCR. During the 8-year follow-up, Cox regression analysis was done to investigate the associations between pain interference and incident MCR.

RESULTS

The study included 7120 older adults (74.6 ± 6.7 years; 56.8% females) at baseline. The baseline prevalence of MCR was 5.7%. Individuals with interfering pain had a significantly increased risk of MCR (OR = 1.51, 95% CI = 1.17-1.95; p = 0.001). The longitudinal analysis included 4605 participants, and there were 284 (6.2%) MCR cases on follow-up. Participants with interfering pain at baseline had a higher risk for MCR at 8 years of follow-up (HR = 2.02, 95% CI = 1.52-2.69; p < 0.001).

CONCLUSIONS

Older adults with interfering pain had a higher risk for MCR versus those with non-interfering pain or without pain. Timely and adequate management of interfering pain may contribute to the prevention and treatment of MCR and its associated adverse outcomes.

Perceived Efficacy, Reduced Prescription Drug Use, and Minimal Side Effects of Cannabis in Patients with Chronic Orthopedic Pain

Introduction: Although cannabis is widely used for the treatment of chronic pain, most research relies on patient self-report and few studies have objectively quantified its efficacy and side effects. Extant inventories for measuring cannabis use were not designed to capture the medically relevant features of cannabis use, but rather were designed to detect problematic use or cannabis use disorder. Thus, we sought to capture the medically relevant features of cannabis use in a population of patients with orthopedic pain and pair these data with objective measures of pain and prescription drug use. Materials and Methods: In this prospective observational study, orthopedic pain patients were enrolled in Pennsylvania's medical cannabis program by their treating pain management physician, received cannabis education from their physician at the time of certification, and purchased products from state-licensed cannabis retailers. Results: Medical cannabis use was associated with clinical improvements in pain, function, and quality of life with reductions in prescription drug use; 73% either ceased or decreased opioid consumption and 31% discontinued benzodiazepines. Importantly, 52% of patients did not experience intoxication as a side effect of cannabis therapy. Significant clinical benefits of cannabis occurred within 3 months of initiating cannabis therapy and plateaued at the subsequent follow-ups. Conclusions: This work provides a direct relationship between the initiation of cannabis therapy and objectively fewer opioid and benzodiazepine prescriptions. Our work also identifies specific subpopulations of patients for whom cannabis may be most efficacious in reducing opioid consumption, and it highlights the importance of both physician involvement and patient self-titration in symptom management with cannabis.

Incident Functional Limitations Among Community-Dwelling Adults Using Opioids: A Retrospective Cohort Study Using a Propensity Analysis with the Health and Retirement Study

BACKGROUND

Opioid analgesics are commonly used to manage pain; however, it is unclear how they affect patient function. This study examines the association between opioid analgesics and incident limitations in activities of daily living (ADL), instrumental activities of daily living (IADL), and cognitive functioning among community-dwelling older adults.

METHODS

Data included 10,003 participants of the 2016 and 2018 waves of the Health and Retirement Study, which sampled US adults aged 51-98 years. The primary exposure was self-reported opioid pain medication use in 2016. Outcomes included incident limitations in ADL, IADL, and cognitive functioning in 2018. Statistical methods adjusted for confounding using multivariable logistic regressions, inverse probability of treatment weighting, and propensity scores.

RESULTS

Opioid use (adjusted odds ratio [aOR]: 1.34, 95% confidence interval [CI] 1.07-1.68) was associated with a statistically significant higher odds of incident ADL limitation in multivariable regression and in propensity score adjustment (aOR: 1.41, 95% CI 1.13-1.76). The association between opioid use and ADL and IADL limitations was modified by age. Adults aged < 65 years had a higher odds of incident ADL (aOR: 1.83, 95% CI 1.38-2.42) and IADL (aOR: 1.42, 95% CI 1.06-1.90) limitations compared with those aged ≥ 65 years.

CONCLUSIONS

Community-dwelling adults using opioid analgesics to manage pain may be at risk for incident ADL limitations. Middle-aged adults, compared with those older than 65 years of age, experienced the greatest odds for incident ADL and IADL limitations following opioid use. According to sensitivity analyses, our findings were robust to unmeasured confounding.

Neurocognitive and substance use disorders in older adults: challenges and evidence

Purpose

This study aims to review the presentation of substance use disorders in older adults, how addiction intertwines with neurocognitive disorders and how to approach this vulnerable population.

Design/methodology/approach

Electronic data searches of PubMed, Medline and the Cochrane Library (years 2000–2021) were performed using the keywords “neurocognitive,” “dementia,” “substance use,” “addiction,” “older adults” and “elderly.” The authors, in consensus, selected pivotal studies and conducted a narrative synthesis of the findings.

Findings

Research about substance use disorders in older adults is limited, especially in those with superimposed neurocognitive disorders. Having dual diagnoses can make the identification and treatment of either condition challenging. Management should use a holistic multidisciplinary approach that involves medical professionals and caregivers.

Originality/value

This review highlights some of the intertwining aspects between substance use disorders and neurocognitive disorders in older adults. It provides a comprehensive summary of the available evidence on treatment in this population.

Persistence of pain and cognitive impairment in older adults

BACKGROUND

No studies have examined the longitudinal association between the persistence of pain and its relationship to cognitive problems in older adults. The objective of this study was to examine how the persistent of pain associates with cognitive performance, cognitive impairment, and subjective memory decline.

METHODS

Across 10 biennial waves, 8515 adults ages 65 and over were assessed from the Health and Retirement Study (M_age  = 74.17, SD = 6.87, 59.2% female). At each wave, individuals were asked to report on pain presence, and if present, rate its intensity and interference with daily activities such as housework or chores. Using running frequencies or averages, we calculated the persistence of pain using these three pain measures. Cognition was assessed using cognitive performance and different cognitive impairment cutoffs. Incident subjective memory decline was additionally measured as new self-reported memory change in the last 2 years. General estimating equations examined concurrent associations between persistence of pain and cognitive variables, adjusting for demographics, depressive symptoms, and medical comorbidities.

RESULTS

Persistence of pain presence was associated with an increased risk of cognitive impairment. Only persistence of pain interference, not pain intensity, was significantly associated with poorer cognitive performance or being classified as cognitively impaired. For every 2 years, persistence of pain interference was associated with 21% increased odds of cognitive impairment. Only one of three pain variables was related to incident subjective memory decline.

CONCLUSIONS

Persistence of pain is associated with poorer cognitive performance in community-dwelling older adults, especially when involving ongoing interference in chores and work. Facilitating pain management might be important for helping to maintain later-life cognition and reduce dementia risk.

Mind-body approaches targeting the psychological aspects of opioid use problems in patients with chronic pain: evidence and opportunities

Opioids are commonly prescribed for the management of patients with chronic noncancer pain. Despite the potential analgesic benefits of opioids, long-term opioid therapy (LTOT) may be accompanied by problems such as opioid misuse and opioid use disorder (OUD). In this review, we begin with a description of opioid misuse and OUD and the patient-specific factors associated with these problems among patients with chronic pain. We will focus primarily on highlighting the predominant role played by psychological factors in the occurrence of opioid misuse and OUD in these patients. Several psychological factors have been found to be associated with opioid use problems in patients with chronic pain, and evidence indicates that patients presenting with psychological disturbances are particularly at risk of transitioning to long-term opioid use, engaging in opioid misuse behaviors, and developing OUD. The biological factors that might underlie the association between psychological disturbances and opioid use problems in patients with chronic pain have yet to be fully elucidated, but a growing number of studies suggest that dysfunctions in reward, appetitive, autonomic, and neurocognitive systems might be involved. We end with an overview of specific types of psychological interventions that have been put forward to prevent or reduce the occurrence of opioid misuse and OUD in patients with chronic pain who are prescribed LTOT.

Prescription opioid misusers exhibit blunted parasympathetic regulation during inhibitory control challenge

RATIONALE

Among opioid-treated chronic pain patients, response inhibition deficits in emotional contexts may contribute to opioid misuse.

OBJECTIVES

Using high-frequency heart rate variability (HF-HRV) to index-impaired response inhibition, we examined associations between opioid misuse and response inhibition in emotional and neutral contexts in a sample of opioid-treated chronic pain patients.

METHOD

Chronic pain patients taking opioid analgesics (N = 97) for ≥ 90 days completed an Emotional Go/NoGo task that presented an inhibitory control challenge in the context of neutral, opioid, negative affective, and positive affective background images while HF-HRV was computed. Opioid misuse and craving were assessed. Using a validated cut-point on the Current Opioid Misuse Measure, participants were classified as opioid misusers or non-misusers. Opioid misuse was examined as a predictor of behavioral and HF-HRV metrics of response inhibition.

RESULTS

Negative affective and opioid images elicited more errors of commission (p = .002, η²_partial = .16) and slowed reaction times (p = .045, η²_partial = .09) compared to neutral and positive affective images, respectively. Though no between-group behavioral differences were observed on the task, opioid misusers exhibited significantly blunted phasic HF-HRV during the task relative to non-misusers (p = .027, η²_partial = .11). HF-HRV during the task was significantly inversely associated with opioid craving. It was not clear whether these autonomic findings reflected a durable phenotypic difference between groups or between-group differences in opioid dosing and withdrawal.

CONCLUSION

Reduced parasympathetic regulation during inhibitory control challenge may indicate heightened opioid misuse risk among opioid-treated chronic pain patients.

Effects of Mindfulness-Oriented Recovery Enhancement Versus Social Support on Negative Affective Interference During Inhibitory Control Among Opioid-Treated Chronic Pain Patients: A Pilot Mechanistic Study

BACKGROUND

Among opioid-treated chronic pain patients, deficient response inhibition in the context of emotional distress may contribute to maladaptive pain coping and prescription opioid misuse. Interventions that aim to bolster cognitive control and reduce emotional reactivity (e.g., mindfulness) may remediate response inhibition deficits, with consequent clinical benefits.

PURPOSE

To test the hypothesis that a mindfulness-based intervention, Mindfulness-Oriented Recovery Enhancement (MORE), can reduce the impact of clinically relevant, negative affective interference on response inhibition function in an opioid-treated chronic pain sample.

METHODS

We examined data from a controlled trial comparing adults with chronic pain and long-term prescription opioid use randomized to either MORE (n = 27) treatment or to an active support group comparison condition (n = 30). Participants completed an Emotional Go/NoGo Task at pre- and post-treatment, which measured response inhibition in neutral and clinically relevant, negative affective contexts (i.e., exposure to pain-related visual stimuli).

RESULTS

Repeated-measures analysis of variance indicated that compared with the support group, participants in MORE evidenced significantly greater reductions from pre- to post-treatment in errors of commission on trials with pain-related distractors relative to trials with neutral distractors, group × time × condition F(1,55) = 4.14, p = .047, η2partial = .07. Mindfulness practice minutes and increased nonreactivity significantly predicted greater emotional response inhibition. A significant inverse association was observed between improvements in emotional response inhibition and treatment-related reductions in pain severity by 3-month follow-up.

CONCLUSIONS

Study results provide preliminary evidence that MORE enhances inhibitory control function in the context of negative emotional interference.

Association between prescribed central nervous system depressant drugs, comorbidity and cognition among hospitalised older patients: a cross-sectional study

OBJECTIVES

Central nervous system depressants (CNSDs) such as opioids, benzodiazepine and Z-hypnotics are commonly used. However, CNSDs may influence cognitive function, especially in older hospitalised patients with comorbidities. The aim was to examine the association between CNSD use and cognitive function in older patients. We assessed global and domain specific cognitive function, among hospitalised older patients, including covariates for comorbidity, anxiety and depression.

DESIGN

Cross-sectional hospital-based study.

SETTINGS

Data was collected consecutively from inpatients at somatic wards of a general university hospital.

PARTICIPANTS

Older patients between 65 and 90 years with/without CNSD use for ≥4 weeks.

OUTCOME MEASURES

The main outcome was cognitive function assessed by Cognistat. Secondary outcomes were routine clinical tests in the wards (mini-mental state examination (MMSE), trail making test (TMT) A and B, and clock drawing tests). Analyses were bivariate and multiple linear regression, adjusted for age, gender, and education. Covariates were comorbidity, depression and anxiety scores.

RESULTS

The main result indicated that CNSD users (n=100) had (β=-3.4, 95% CI 6.27 to -0.58, p=0.017) lower Cognistat score than non-users (n=146), adjusted for age, gender, education, anxiety and depression, but not significant when including covariate for comorbidity (β= -2.50 - 5.45; -0.46, p=0.097). Comorbidity was associated with cognitive function (β=-0.77, 95% CI -1.22 to -0.14, p=0.014). Cognistat subdimensions associated with CNSD use were language (p=0.017) and calculation (p=0.003). In clock drawing test, users had lower scores than non-users (β=-0.80, 95% CI 1.24 to -0.36, p=0.004), but no significant difference was found with MMSE and TMT A or B. Z-hypnotics were associated with reduced cognitive function.

CONCLUSION

Among older hospitalised patients, global cognition and specific cognitive functions were associated with long-term use of CNSD medication as well as with somatic comorbidity.

TRIAL REGISTRATION NUMBER

NCT03162081, 22 May 2017.

Exploring stress, cognitive, and affective mechanisms of the relationship between interpersonal trauma and opioid misuse

BACKGROUND

People with a history of interpersonal trauma, including intimate partner violence, sexual assault, and adverse childhood experiences, are disproportionately affected by the current opioid epidemic. Interpersonal trauma has been shown to increase risk for chronic pain conditions, prescription opioid use, and opioid misuse. Stress, cognition, and affective function have been examined as potential mechanisms that may influence opioid misuse among individuals with a history of interpersonal trauma. However, no studies have examined these factors simultaneously, despite their interrelatedness.

OBJECTIVE

The purpose of this study was to 1) examine perceived stress, perceived cognitive function, depressive symptoms, and PTSD symptoms as potential mechanisms of opioid misuse among individuals with a history of interpersonal trauma, 2) examine the types of interpersonal trauma that are associated with opioid misuse, and 3) assess the mediating role of pain and opioid prescription.

METHODS

A cross-sectional, observational study design was conducted. Data were collected through a confidential self-report online survey using validated instruments (n = 230). A series of regression analyses were conducted to identify mechanistic factors and interpersonal trauma types associated with opioid misuse, opioid prescription, and pain intensity. Structural equation modeling was used to examine mediating effects of pain intensity and opioid prescription.

RESULTS

Opioid prescription, depressive symptoms, and intimate partner violence increased the odds of reporting opioid misuse. Pain intensity and adverse childhood experiences increased the odds of opioid prescription. Higher levels of perceived stress and depressive symptoms were associated with increased pain intensity. Pain intensity emerged as a mediator of the relationship between depressive symptoms and opioid misuse.

CONCLUSIONS

Our work shows that there are likely several pathways through which interpersonal trauma can lead to opioid misuse. Interventions aimed at improving depressive symptoms and coping with traumatizing events should be included as part of comprehensive trauma-informed pain management practices.

The Effects of Opioids on Cognition in Older Adults With Cancer and Chronic Noncancer Pain: A Systematic Review

CONTEXT

Opioids are prescribed to manage moderate-to-severe pain and can be used with older adults; however, they may lead to several adverse effects, including cognitive impairment.

OBJECTIVES

To identify, appraise, and synthesize evidence on the impact of opioids on cognition in older adults with cancer/chronic noncancer pain, and screening tools/neuropsychological assessments used to detect opioid-induced cognitive impairment.

METHODS

A systematic literature review following the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (international prospective register of systematic reviews registration: CRD42018092943). MEDLINE, EMBASE, PsycINFO, CINAHL, Cochrane Library, and Web of Science were searched up to December 2018. Randomized controlled trials, quasi-experimental studies, and observational studies of adults aged 65 years and older with cancer/chronic noncancer pain taking opioids were included. A narrative synthesis was conducted.

RESULTS

From 4036 records, 10 met inclusion criteria. Five studies used one screening tool, and five studies used a range of neuropsychological assessments; assessing 14 cognitive domains. Most studies demonstrated no effect of opioid use on cognitive domains, whereas four studies showed mixed effects. In particular, attention, language, orientation, psychomotor function, and verbal working/delayed episodic memory were worsened. Changes to cognitive function were predominantly observed in studies with higher mean doses of opioids (120-190.7mg oral morphine equivalent daily dose).

CONCLUSION

Both improvements and impairments to cognition were observed in studies with higher mean opioid doses. In clinical practice, a brief screening tool assessing attention, language, orientation, psychomotor function, and verbal working/delayed episodic memory may be beneficial to detect worsening cognition in older adults with chronic pain using opioids.

Patient reported outcomes and neuropsychological testing in patients with chronic non-cancer pain in long-term opioid therapy: a pilot study

Background and aims Opioid consumption has increased dramatically in patients with chronic non-cancer pain (CNCP), but long-term consequences are still unclear. The aim of this study is to investigate the effects of long-term opioid treatment on pain, cognition, mood, sleep and quality of life in CNCP patients. Methods In this cross-sectional pilot study, two groups of patients with CNCP treated in a multidisciplinary pain center were selected: (1) opioid group: ≥30 mg morphine equivalent/day for >4 weeks, and (2) control group: no opioid consumption for >4 weeks. Socio-demographic data, alcohol consumption, smoking habits and body mass index (BMI) were registered and pain (brief pain inventory), mood (Hospital Anxiety and Depression Scale), sleep (Pittsburgh Sleep Quality Index) and quality of life (RAND 36-Item Health Survey) were assessed. Continuous Reaction Time and the Digit Span Test were used to evaluate cognitive function. Data was analyzed with a Fisher's exact test and Wilcoxon two-sample test. Results Forty-two patients with CNCP were included (21 in each group). No differences regarding socio-demographics, smoking/alcohol habits and duration, type, or intensity of pain were found. More patients in the opioid group had significantly higher BMI (62% above BMI 25 vs. 33.3%, p = 0.042). Consequently, the subsequent data analyses were controlled for BMI. The two groups did not differ in pain, cognition, anxiety, depression, sleep or quality of life but both showed lower values than the normal standards. Further, the opioid group presented a tendency to lower ratings regarding pain and social function and performed below the normal cut off in the continuous reaction time. Conclusions No significant differences between the two groups were found regarding any of the above-mentioned variables. Interestingly, the patients assessed, regardless of taking opioids or not, could be classified with moderate pain intensity, anxiety and low quality of sleep and life compared to norm standards. Implications The findings of this pilot study suggested that long-term opioid treatment may influence pain and quality of life among CNCP patients. A larger cohort is needed to verify these findings.

Neuropsychological Changes in Complex Regional Pain Syndrome (CRPS)

Complex Regional Pain Syndrome (CRPS) is a poorly understood chronic pain condition of multifactorial origin. CRPS involves sensory, motor, and autonomic symptoms primarily affecting one extremity. Patients can also present with neuropsychological changes such as reduced attention to the CRPS-affected extremity, reminiscent of hemispatial neglect, yet in the absence of any brain lesions. However, this "neglect-like" framework is not sufficient to characterise the range of higher cognitive functions that can be altered in CRPS. This comprehensive literature review synthesises evidence of neuropsychological changes in CRPS in the context of potential central mechanisms of the disorder. The affected neuropsychological functions constitute three distinct but not independent groups: distorted body representation, deficits in lateralised spatial cognition, and impairment of non-spatially-lateralised higher cognitive functions. We suggest that many of these symptoms appear to be consistent with a broader disruption to parietal function beyond merely what could be considered "neglect-like." Moreover, the extent of neuropsychological symptoms might be related to the clinical signs of CRPS, and rehabilitation methods that target the neuropsychological changes can improve clinical outcomes in CRPS and other chronic pain conditions. Based on the limitations and gaps in the reviewed literature, we provide several suggestions to improve further research on neuropsychological changes in chronic pain.

A Biopsychosocial Model of Chronic Pain for Older Adults

Population

Comprehensive evaluation of chronic pain in older adults is multifaceted.

Objective and Methods

Research on chronic pain in older adults needs to be guided by sound conceptual models. The purpose of this paper is to describe an adaptation of the Biopsychosocial Model (BPS) of Chronic Pain for older adults. The extant literature was reviewed, and selected research findings that provide the empiric foundation for this adaptation of the BPS model of chronic pain are summarized. The paper concludes with a discussion of specific recommendations for how this adapted model can be used to guide future research.

Conclusions

This adaptation of the BPS model of chronic pain for older adults provides a comprehensive framework to guide future research in this vulnerable population.

Insomnia-related Memory Impairment in Individuals With Very Complex Chronic Pain

OBJECTIVE

To investigate the specific effect of insomnia on neuropsychological functioning in patients with very complex chronic pain.

BACKGROUND

Individuals with insomnia disorder or chronic pain often experience cognitive deficits, with both conditions appearing to correlate with impairments in neuropsychological functions. As insomnia often occurs comorbid with chronic pain, distinguishing the differential effects of these two syndromes on an individual's neuropsychological functioning can be challenging. Comorbid depressive symptoms in these individuals, which may also affect cognitive function, may further obscure the associations between chronic pain, insomnia, and the neuropsychological profile.

METHODS

The neuropsychological function of 22 individuals with very complex chronic pain was assessed using specialized tests examining aspects of memory and executive functioning. The severity of insomnia, depression, and anxiety was measured using questionnaires, and pain levels were assessed using a visual analog scale. Pain medications were transformed to the morphine-equivalent daily dose.

RESULTS

Insomnia severity was found to predict memory function, accounting for 32.4% of the variance: A 1 SD increase in insomnia severity decreased memory function by 0.57 SD. The negative correlation between insomnia and memory was significant even after controlling for pain level, morphine-equivalent daily dose, and comorbid levels of anxiety and depression.

CONCLUSIONS

Insomnia severity independently predicted memory function in patients with very complex chronic pain, even after controlling for other factors known to impair cognitive function. Insomnia may possibly explain some of the cognitive impairments related to chronic pain; thus, screening for, and treating, sleep disturbances may be a central aspect of chronic pain rehabilitation.

Pain therapy - Are there new options on the horizon?

This article reviews the role of analgesic drugs with a particular emphasis on opioids. Opioids are the oldest and most potent drugs for the treatment of severe pain, but they are burdened by detrimental side effects such as respiratory depression, addiction, sedation, nausea, and constipation. Their clinical application is undisputed in acute (e.g., perioperative) and cancer pain, but their long-term use in chronic pain has met increasing scrutiny and has contributed to the current opioid crisis. We discuss epidemiological data, pharmacological principles, clinical applications, and research strategies aiming at novel opioids with reduced side effects.

The Association of Perceived Memory Loss with Osteoarthritis and Related Joint Pain in a Large Appalachian Population

Objective

Previous studies have documented memory impairment in several chronic pain syndromes. However, the potential link between memory loss and osteoarthritis (OA), the second most common cause of chronic pain, remains little explored. In this cross-sectional study, we examine the association of perceived memory loss to OA and assess the potential mediating influence of sleep and mood disturbance in a large Appalachian population.

Design

Cross-sectional.

Setting

US Ohio Valley.

Subjects

A total of 21,982 Appalachian adults age 40 years or older drawn from the C8 Health Project (N = 19,004 adults without and 2,478 adults with OA). All participants completed a comprehensive health survey between 2005 and 2006. Medical history, including physician diagnosis of OA, lifestyle factors, short- and long-term memory loss, sleep quality, and mood were assessed via self-report.

Results

After adjustment for demographic, lifestyle, health-related, and other factors, participants with OA were almost three times as likely to report frequent memory loss (adjusted odds ratios [ORs] for short- and long-term memory loss, respectively = 2.7, 95% confidence interval [CI] = 2.2-3.3, and 2.6, 95% CI = 2.0-3.3). The magnitude of these associations increased significantly with rising frequency of reported joint pain (adjusted OR for OA with frequent joint pain vs no OA = 3.3, 95% CI = 2.6-4.1, Ptrend < 0.00001). Including measures of mood and sleep impairment attenuated but did not eliminate these associations (ORs for any memory loss = 2.0, 95% CI = 1.6-2.4, and 2.1, 95% CI = 1.7-2.8, adjusted for sleep and mood impairment, respectively; OR = 1.8, 95% CI = 1.4-2.2, adjusted for both factors).

Conclusions

In this large cross-sectional study, OA and related joint pain were strongly associated with perceived memory loss; these associations may be partially mediated by sleep and mood disturbance.

Neurocognitive Difficulties Among Youth with POTS within an Intensive Pain Rehabilitation Program

OBJECTIVE

Adolescents and young adults (AYAs) with postural orthostatic tachycardia syndrome (POTS) commonly report cognitive difficulties, though there is limited information regarding the objective measurement of neurocognitive deficits in this population. This study described the rates of subjectively experienced and objectively measured neurocognitive difficulties and explored effects of medications on neurocognitive functioning among AYAs with POTS admitted to an intensive outpatient pain rehabilitation program.

METHODS

Participants in a pain rehabilitation program diagnosed with POTS (N = 96; ages 12-22) were included in the study. Medical characteristics, reported cognitive complaints, and neurocognitive assessment results were collected through retrospective medical record review. We calculated descriptive statistics and Pearson's χ2 or Fisher's exact tests, where appropriate.

RESULTS

While 96% of this sample reported subjective cognitive complaints, as a group, they performed in the Average range on standardized measures of intellectual functioning, attention, and memory. The majority did not demonstrate any normative (73%) or relative (54%) weaknesses in attention or memory. Those prescribed an antiepileptic (n = 19) were less likely to have visual-spatial memory weaknesses but more likely to have attention weaknesses.

CONCLUSIONS

Despite a high frequency of reported cognitive difficulties, most AYAs with POTS did not demonstrate neurocognitive impairment on standardized, one-on-one assessment. Suggestions for further study of biopsychosocial contributors to neurocognitive difficulties and for clinical use of neurocognitive assessments in this population were provided.

Tapentadol: an analgesic that differs from classic opioids due to its noradrenergic mechanism of action

Chronic pain treatment represents one of the most complex clinical challenges and even though opioids exhibit particular efficacy on nociceptive pain, their use must be controlled to avoid the risk of adverse reactions. A useful approach, aimed at maintaining analgesia and mitigating side effects, is represented by the use of a new class of analgesics endowed of µ-opioid (MOR) receptor agonism and noradrenaline reuptake inhibition (NRI) mechanisms. Tapentadol is the progenitor of this new class of drugs called MOP-NRI. A literature review has been conducted to gain information about the efficacy and the tolerability profile of tapentadol shifting from MOR agonism (acute pain) to NRI activity (chronic pain). The tolerability and therapeutic safety of tapentadol in neuropathic pain models, as well as in clinical settings, has been analyzed showing a good gastrointestinal tolerability profile, a moderate effect on hormone levels (in healthy volunteers and in patients) and on cognitive performance, a lack of significant alteration of the electrocardiogram recording and no changes of the QT/QTc interval, a minimal effect on serotonin reuptake in vivo with a low risk of serotonin syndrome, a longer time for the onset of analgesic tolerance and a less occurrence of abuse liability compared to formulations containing other comparator compounds. Tapentadol represents a great innovation in chronic pain therapy with a unique analgesic profile different form classical opioids, therefore, thanks to its synergistic MOR-NRI action, it may be a good option for the treatment of chronic, neuropathic and mixed pain.

Cognitive and socio-cognitive functioning of chronic non-medical prescription opioid users

RATIONALE

Non-medical prescription opioid use (NMPOU) has become a major public health issue in the USA and is also increasing in Europe. However, little is known about neuropsychological associations of NMPOU-specifically regarding social cognition, which is essential for social functioning and treatability of opioid dependence. Previous studies with heroin users and opioid-substituted patients reported deficits in various cognitive functions, but these results are likely confounded by comorbid physical and psychiatric diseases, overdose-associated hypoxia, and adulteration of street heroin. Therefore, the purpose of the present study was to investigate social and non-social cognition in a relatively pure NMPOU sample taking opioid analgesics or antitussives.

METHODS

We assessed 23 individuals with NMPOU objectively confirmed by hair analyses and 29 opioid-naïve, healthy controls, employing a comprehensive neuropsychological test battery.

RESULTS

Significant impairments were found between NMPOU individuals and controls regarding the cognitive domains of attention (p < .01, Hedge's g = .85), declarative memory (p < .05, g = .66), and global cognitive empathy (p < .01, g = 0.99)-the latter included problems with emotion recognition from faces, voices, and complex scenes. Opioid hair concentrations transformed to morphine equivalents were negatively correlated with global cognitive empathy (r = - 0.52, p < .01), suggesting dose-dependent deficits.

CONCLUSION

In contrast to stimulant users primarily displaying deficits in emotional empathy, opioid users showed relatively selective impairments in measures of cognitive empathy, with dose-dependent effects suggesting potential opioid-induced deficits and involvement of the opioid-system in processes of cognitive empathy. These results have important implications for future interventions of opioid dependence targeting social functioning and consequently enhancing therapy outcome and preventing relapse.

Opioids in oral fluid of Spanish drivers

BACKGROUND

Driving under the influence of certain drugs is not allowed, and roadside drug testing is being considered an important tool for deterring driving under the influence of them. This study aimed to assess the presence and concentration of opioids, as well as their combined use with other drugs (laboratory confirmation after the on-road screening) in Spanish drivers between 2011 and 2016.

METHODS

In Spain, mandatory roadside breath alcohol and oral fluid drug testing (screening) are carried out by the Traffic Police using Dräger Alcotest^® 6810 device, and Dräger DrugTest^® 5000, DrugWipe^®, or Alere™ DDS^®2 Mobile Test System. For positive cases in the period covered, 65,244, confirmation analysis and quantification using chromatographic techniques were performed.

RESULTS

Opioids were confirmed in 8.6% of positive cases, being 7.2% positives to 6-acetylmorphine (6-AM), 6.5% to morphine, 5.4% to codeine, and 4.1% to methadone. The majority of the confirmed tests for morphine (96.5%), codeine (88.4%) and methadone (81.9) were also positive for 6-AM. The presence of other drugs, particularly cocaine and cannabis, was very common. Concentration values reached important levels. Positive results for morphine (0.1%), codeine (0.6%) or methadone (0.4%) alone were very infrequent.

CONCLUSIONS

Drivers with a confirmed positive roadside test for morphine, codeine, and methadone had also consumed heroin and/or other illicit drugs, such as cocaine and/or THC, and at relevant concentrations. Improving interventions to combat the problem of driving under the influence of driving-impairing substances is a priority.

Cognitive Impairment in Patients with Chronic Neuropathic or Radicular Pain: An Interaction of Pain and Age

A growing body of empirical research has confirmed an association between chronic pain and cognitive dysfunction. The aim of the present study was to determine whether cognitive function is affected in patients with a diagnosis of chronic neuropathic or radicular pain relative to healthy control participants matched by age, gender, and years of education. We also examined the interaction of pain with age in terms of cognitive performance. Some limitations of previous clinical research investigating the effects of chronic pain on cognitive function include differences in the pain and cognitive scale materials used, and the heterogeneity of patient participants, both in terms of their demographics and pathological conditions. To address these potential confounds, we have used a relatively homogenous patient group and included both experimental and statistical controls. We have also specifically investigated the interaction effect of pain and age on cognitive performance. Patients (n = 38) and controls (n = 38) were administered a battery of cognitive tests measuring IQ, spatial and verbal memory, attention, and executive function. Educational level, depressive symptoms, and state anxiety were assessed as were medication usage, caffeine, and nicotine consumption to control for possible confounding effects. Both the level of depressive symptoms and the state anxiety score were higher in chronic pain patients than in matched control participants. Chronic pain patients had a lower estimated IQ than controls, and showed impairments on measures of spatial and verbal memory. Attentional responding was altered in the patient group, possibly indicative of impaired inhibitory control. There were significant interactions between chronic pain condition and age on a number of cognitive outcome variables, such that older patients with chronic pain were more impaired than both age-matched controls and younger patients with chronic pain. Chronic pain did not appear to predict performance on the Wisconsin Card Sorting Task, which was used a measure of executive function. This study supports and extends previous research indicating that chronic pain is associated with impaired memory and attention.

Perspective: Compared to healthy control participants, patients with chronic neuropathic or radicular pain showed cognitive deficits which were most pronounced in older pain patients.

Roadside opioid testing of drivers using oral fluid: the case of a country with a zero tolerance law, Spain

Background

Opioids can impair psychomotor performance, and driving under the influence of opioids is associated with an increased risk of accidents. The goals of this study were i) to determine the prevalence of opioids (heroin, morphine, codeine, methadone and tramadol) in Spanish drivers and ii) to explore the presence of opioids, more specifically whether they are used alone or in combination with other drugs.

Methods

The 2008/9 DRUID database regarding Spain was used, which provided information on 3302 drivers. All drivers included in the study provided a saliva sample and mass-chromatographic analyses were carried out in all cases. To determine the prevalence, the sample was weighted according to traffic intensity. In the case of opioid use combinations, the sample was not weighted. The detection limit for each substance was considered a positive result.

Results

The prevalence of opioids in Spanish drivers was 1.8% (95% CI, 1.4–2.3). Polydrug detection was common (56.2%): of these, in two out of three cases, two opioids were detected and cocaine was also detected in 86% of the cases. The concentration (median [Q1-Q3] ng/ml) of the substances was low: methadone 1.71 [0.10–15.30], codeine 40.55 [2.10–120.77], 6-acetylmorphine 5.71 [1.53–84.05], and morphine 37.40 [2.84–200.00]. Morphine was always detected with 6-acetylmorphine (heroin use).

Conclusions

Driving under the influence of opioids is relatively infrequent, but polydrug use is common. Our study shows that 6 out of 10 drivers with methadone in their OF (likely in methadone maintenance programs) are using other substances. This should be taken into account by health professionals in order to properly inform patients about the added risks of mixing substances when driving.

Opiate Analgesics as Negative Modulators of Adult Hippocampal Neurogenesis: Potential Implications in Clinical Practice

During the past decade, studies of the mechanisms and functional implications of adult hippocampal neurogenesis (ahNG) have significantly progressed. At present, it is proposed that adult born neurons may contribute to a variety of hippocampal-related functions, including specific cognitive aspects and mood regulation. Several groups focussed on the factors that regulate proliferation and fate determination of adult neural stem/progenitor cells (NSC/NPC), including clinically relevant drugs. Opiates were the first drugs shown to negatively impact neurogenesis in the adult mammalian hippocampus. Since that initial report, a vast array of information has been collected on the effect of opiate drugs, by either modulating proliferation of stem/progenitor cells or interfering with differentiation, maturation and survival of adult born neurons. The goal of this review is to critically revise the present state of knowledge on the effect of opiate drugs on the different developmental stages of ahNG, as well as the possible underlying mechanisms. We will also highlight the potential impact of deregulated hippocampal neurogenesis on patients undergoing chronic opiate treatment. Finally, we will discuss the differences in the negative impact on ahNG among clinically relevant opiate drugs, an aspect that may be potentially taken into account to avoid long-term deregulation of neural plasticity and its associated functions in the clinical practice.

Abhängigkeitspotenzial und andere Risiken von Opioidanalgetika im Alter

Zusammenfassung. Zielsetzung: Übersicht über Suchtpotenzial und andere Risiken von Opioidanalgetika im höheren Lebensalter. Methodik: Narrativ review. Literaturrecherche in PubMed (Suchbegriffe: opioid analgesics UND abuse; opioid analgesics UND dependence; opioid analgesics UND addiction; opioid analgesics UND adverse effects; jeweils UND elderly) sowie aktuellen einschlägigen Standardwerken; Auswahl nach altersmedizinischer Relevanz und Aktualität. Ergebnisse: Die Verordnung von Opioidanalgetika (OA) hat in den letzten 25 Jahren massiv zugenommen, die weitaus meisten Verordnungen entfallen auf alte Menschen und Menschen mit chronischen Nicht-Tumorschmerzen (CNTS). Die diagnostischen Kriterien für die Opiatabhängigkeit in ICD-10 und DSM-5 sind für die OA-Behandlung von CNTS ungeeignet. Bei langfristiger OA-Behandlung bei CNTS kann eine spezifische Form von Abhängigkeit entstehen, die nicht mit der illegalen Opiat-(Heroin-)Sucht gleichzusetzen ist. Vorbestehende Suchterkrankungen und andere psychische Störungen sind die wesentlichsten Risikofaktoren. Weitere Nebenwirkungen sind zu beachten. Schmerztherapie bei Suchtkranken stellt eine besondere Herausforderung dar. Schlussfolgerungen: Die Anwendung von OA bei CNTS verlangt eine sorgfältige Indikationsstellung. Die besondere Form der Abhängigkeit von OA ist nicht ausreichend erforscht und wird zu wenig beachtet.

Effect of chronic opioid therapy on actual driving performance in non-cancer pain patients

RATIONALE

Chronic non-cancer pain (CNCP) is a major health problem. Patients are increasingly treated with chronic opioid therapy (COT). Several laboratory studies have demonstrated that long-term use of opioids does not generally impair driving related skills. But there is still a lack of studies investigating on-the-road driving performance in actual traffic.

OBJECTIVES

The present study assessed the impact of COT on road-tracking and car-following performance in CNCP patients.

METHODS

Twenty CNCP patients, long-term treated with stable doses of opioid analgesics, and 19 healthy controls conducted standardized on-the-road driving tests in normal traffic. Performance of controls with a blood alcohol concentration (BAC) of 0.5 g/L was used as a reference to define clinically relevant changes in driving performance.

RESULTS

Standard Deviation of Lateral Position (SDLP), a measure of road-tracking control, was 2.57 cm greater in CNCP patients than in sober controls. This difference failed to reach statistical significance in a superiority test. Equivalence testing indicated that the 95% CI around the mean SDLP change was equivalent to the SDLP change seen in controls with a BAC of 0.5 g/L and did not include zero. When corrected for age differences between groups the 95% CI widened to include both the alcohol reference criterion and zero. No difference was found in car-following performance.

CONCLUSIONS

Driving performance of CNCP patients did not significantly differ from that of controls due to large inter-individual variations. Hence in clinical practice determination of fitness to drive of CNCP patients who receive opioid treatments should be based on an individual assessment.

New opioid analgesic use and the risk of injurious single-vehicle crashes in drivers aged 50-80 years: A population-based matched case-control study

BACKGROUND

the increasing trend in opioid analgesic use among older drivers has raised concerns about their risk of being involved in car crashes.

AIM

to investigate if older drivers who started using opioid analgesics have a higher probability of being involved in injurious crashes.

METHODS

population-based matched case-control study. Data from population registers were merged using a personal identity number. Cases were drivers aged 50-80 years responsible for a single vehicle crash between 01.07.05 and 31.12.09 that led to at least one injured passenger (n = 4,445). Four controls were randomly matched to each case by sex, birth month/year, and residence area from persons holding a valid driving license who did not crash during the study period. New use was defined as at least one dispensation within 1-30 days prior to the crash, but none within the previous 31-180 days; frequent use when ≥3 dispensations were given within 0-180 days, with at least one within 31-180 days. Individuals using 1-2 non-opioid analgesic medications were used as reference category. Conditional logistic regression was used to estimate odds ratios (OR; 95% CI) adjusting for benzodiazepine use, co-morbidity, civil status and occupation.

RESULTS

adjusted odds for new use were two-fold that of drivers using 1-2 non-opioid analgesics medications (2.0; 1.6-2.5). For frequent use, adjusted odds were also increased regardless of number of dispensations (3-4 = 1.7; 1.3-2.1, 5-6 = 1.6; 1.2-2.3, and ≥7 = 1.7; 1.3-2.1).

CONCLUSION

new, but also frequent opioid analgesic use, resulted in an increased probability of single vehicle crashes. While more epidemiologic evidence is needed, patients could be advised to refrain from driving when using opioid analgesics.

Cognitive Effects and Sedation

OBJECTIVE

Cognitive effects and sedation (CES) are prevalent in chronic nonmalignant pain populations receiving long-term opioid therapy and are among the most common reasons patients discontinue opioid use. In this narrative review, we describe the phenomenology, epidemiology, mechanisms, assessment, and management of opioid-related CES.

DESIGN

We reviewed the empirical and theoretical literature on CES in opioid-treated populations with chronic pain. Data on long-term opioid therapy (≥ 3 months in duration) in chronic nonmalignant pain patients were sought.

RESULTS

The phenomenology of CES includes: inattention, concentration difficulties, memory deficits, psychomotor dysfunction, perceptual distortions, and executive dysfunction and somnolence, sleep disorders, and lethargy. Deficits may be caused by unrelieved pain or opioid therapy alone, or from a combination of these and other factors. Mechanisms include central nervous system effects, for example, direct toxic effects on neurons resulting in decreased consciousness; direct effects on processing and reaction resulting in cognitive or psychomotor impairment, and inhibitory effects on cholinergic activity. Pharmacological management approaches may include opioid dose reduction and rotation or psychostimulant use. Nonpharmacological approaches may include cognitive-behavioral therapy, mindfulness-based stress reduction, acupuncture, exercise, and yoga.

CONCLUSIONS

The most prevalent CES include: memory deficits (73-81%), sleep disturbance (35-57%), and fatigue (10%). At its most severe, extreme cognitive dysfunction can result in frank delirium and decreased alertness can result in coma. Emotional distress, sleep disorders, and other comorbidities and treatments can worsen CES, particularly among the elderly. Conclusions about the neuropsychological domains affected by opioids are limited due to the heterogeneity of studies and methodological issues.

Does mutual compensation of the cognitive effects induced by pain and opioids exist? An experimental study

RATIONALE

Studies have demonstrated that both pain and opioids have actions on the central nervous system that may interfere with cognitive function, but their effects have mainly been analysed separately and not as an integrated process.

OBJECTIVE

The objective of this study is to test two hypotheses: (1) the analgesic effect of opioids improves cognitive function by decreasing pain, and (2) pain antagonizes cognitive effects of opioids.

METHODS

Randomized, placebo-controlled, crossover study. Three experiments were conducted with 22 healthy males. Sustained attention, memory and motor function/attention/mental flexibility were evaluated by continuous reaction time (CRT), verbal fluency test (VFT) and trail making test-B (TMT-B), respectively. In the 1st experiment, the cognitive effects of experimental tonic pain of mild and moderate intensities produced by a computer-controlled pneumatic tourniquet cuff were assessed; in the 2nd, the effects of saline solution and remifentanil were assessed in the absence of pain; and in the 3rd experiment, the cognitive effects of moderate pain intensity relieved by remifentanil infusion were assessed followed by increasing pain to moderate intensity during a constant remifentanil infusion.

RESULTS

The first two experiments demonstrated that pain and remifentanil impaired CRT. In the 3rd experiment, remifentanil infusion relieving pain significantly impaired CRT and further deterioration was noted following increasing pain intensity.

CONCLUSION

Pain and remifentanil seemed to have additive deleterious cognitive effects. This study represents an initial step to enhance our basic understanding of some of the cognitive effects following a painful stimulus and an opioid infusion separately and combined in a sequence comparable to clinical settings.

Driving Ability in Patients with Severe Chronic Low Back or Osteoarthritis Knee Pain on Stable Treatment with Tapentadol Prolonged Release: A Multicenter, Open-label, Phase 3b Trial

Introduction

Strong centrally acting analgesics, including tapentadol prolonged release (PR), have demonstrated efficacy for the management of non-malignant, chronic pain. Maintaining patient independence, including the ability to drive safely, is a key goal of long-term analgesic therapy. This multicenter, open-label, phase 3b trial evaluated the effects of tapentadol PR on driving ability.

Methods

This study included patients who had completed previous tapentadol PR trials for severe low back or osteoarthritis pain. After at least 6 weeks of dose stability, patients continued taking tapentadol PR (50–250 mg twice daily) and could take supplemental immediate-release tapentadol 50 mg, except on the day before or day of the driving test (before the test). Pain intensity was assessed using an 11-point numerical rating scale. The Vienna Test System-Traffic Plus was used to assess cognitive and psychomotor function. The key surrogate parameter for driving ability was a global judgment based on 6 battery tests.

Results

Thirty-eight patients enrolled and completed the trial, and 35 patients completed all 6 tests. Pain scores remained unchanged from enrollment to final visit [mean (standard deviation) change, –0.2 (1.0)]. Approximately two-thirds [65.7% (23/35)] of patients were classified as fit to drive based on the global judgment of driving-specific ability [34.3% (12/35) not fit to drive]. Total daily tapentadol PR dose (>200 vs. ≤200 mg/day) did not affect global judgment of driving ability (P = 0.4885). Two adverse events (considered unrelated to study drug) were reported.

Conclusion

Results suggest that most patients receiving a stable dose of tapentadol PR for severe, chronic pain would be able to drive, consistent with earlier studies evaluating stable treatment with strong opioids. Study design limitations and needs for individual patient assessment must be considered in clinical practice.

Electronic supplementary material

The online version of this article (doi:10.1007/s40122-014-0025-3) contains supplementary material, which is available to authorized users.

The downward spiral of chronic pain, prescription opioid misuse, and addiction: cognitive, affective, and neuropsychopharmacologic pathways

Prescription opioid misuse and addiction among chronic pain patients are emerging public health concerns of considerable significance. Estimates suggest that more than 10% of chronic pain patients misuse opioid analgesics, and the number of fatalities related to nonmedical or inappropriate use of prescription opioids is climbing. Because the prevalence and adverse consequences of this threat are increasing, there is a pressing need for research that identifies the biobehavioral risk chain linking chronic pain, opioid analgesia, and addictive behaviors. To that end, the current manuscript draws upon current neuropsychopharmacologic research to provide a conceptual framework of the downward spiral leading to prescription opioid misuse and addiction among chronic pain patients receiving opioid analgesic pharmacotherapy. Addictive use of opioids is described as the outcome of a cycle initiated by chronic pain and negative affect and reinforced by opioidergic-dopamingeric interactions, leading to attentional hypervigilance for pain and drug cues, dysfunctional connectivity between self-referential and cognitive control networks in the brain, and allostatic dysregulation of stress and reward circuitry. Implications for clinical practice are discussed; multimodal, mindfulness-oriented treatment is introduced as a potentially effective approach to disrupting the downward spiral and facilitating recovery from chronic pain and opioid addiction.

Imaging opioid analgesia in the human brain and its potential relevance for understanding opioid use in chronic pain

Opioids play an important role for the management of acute pain and in palliative care. The role of long-term opioid therapy in chronic non-malignant pain remains unclear and is the focus of much clinical research. There are concerns regarding analgesic tolerance, paradoxical pain and issues with dependence that can occur with chronic opioid use in the susceptible patient. In this review, we discuss how far human neuroimaging research has come in providing a mechanistic understanding of pain relief provided by opioids, and suggest avenues for further studies that are relevant to the management of chronic pain with opioids.

This article is part of the Special Issue Section entitled ‘Neuroimaging in Neuropharmacology’.

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Brain mechanisms are crucial to opioid analgesia in humans.

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Opioids can have a direct effect on brain mechanisms for pain perception.

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Opioids can also engage descending inhibition of spinal nociception.

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Drug-induced tolerance, dependence and paradoxical pain may limit chronic opioid analgesic therapy.

Treating intractable phantom limb pain with ambulatory continuous peripheral nerve blocks: a pilot study

BACKGROUND

There is currently no reliable treatment for phantom limb pain (PLP). Chronic PLP and associated cortical abnormalities may be maintained from abnormal peripheral input, raising the possibility that a continuous peripheral nerve block (CPNB) of extended duration may permanently reorganize cortical pain mapping, thus providing lasting relief.

METHODS

Three men with below-the-knee (2) or -elbow (1) amputations and intractable PLP received femoral/sciatic or infraclavicular perineural catheter(s), respectively. Subjects were randomized in a double-masked fashion to receive perineural ropivacaine (0.5%) or normal saline for over 6 days as outpatients using portable electronic infusion pumps. Four months later, subjects returned for repeated perineural catheter insertion and received an ambulatory infusion with the alternate solution ("crossover"). Subjects were followed for up to 1 year.

RESULTS

By chance, all three subjects received saline during their initial infusion and reported little change in their PLP. One subject did not receive crossover treatment, but the remaining two subjects reported complete resolution of their PLP during and immediately following treatment with ropivacaine. One subject experienced no PLP recurrence through the 52-week follow-up period and the other reported mild PLP occurring once each week of just a small fraction of his original pain (pretreatment: continuous PLP rated 10/10; posttreatment: no PLP at baseline with average of one PLP episode each week rated 2/10) for 12 weeks (lost to follow-up thereafter).

CONCLUSIONS

A prolonged ambulatory CPNB may be a reliable treatment for intractable PLP. The results of this pilot study suggest that a large, randomized clinical trial is warranted.

Cognitive function in patients with chronic pain treated with opioids: characteristics and associated factors

BACKGROUND

The paucity of studies regarding cognitive function in patients with chronic pain, and growing evidence regarding the cognitive effects of pain and opioids on cognitive function prompted us to assess cognition via neuropsychological measurement in patients with chronic non-cancer pain treated with opioids.

METHODS

In this cross-sectional study, 49 patients were assessed by Continuous Reaction Time, Finger Tapping, Digit Span, Trail Making Test-B and Mini-mental State Examination tests. Linear regressions were applied.

RESULTS

Patients scored poorly in the Trail Making Test-B (mean = 107.6 s, SD = 61.0, cut-off = 91 s); and adequately on all other tests. Several associations among independent variables and cognitive tests were observed. In the multiple regression analyses, the variables associated with statistically significant poor cognitive performance were female sex, higher age, lower annual income, lower schooling, anxiety, depression, tiredness, lower opioid dose, and more than 5 h of sleep the night before assessment (P < 0.05).

CONCLUSIONS

Patients with chronic pain may have cognitive dysfunction related to some reversible factors, which can be optimized by therapeutic interventions.

Risk factor assessment for problematic use of opioids for chronic pain

Opioid analgesics provide effective treatment for noncancer pain, but many health providers have concerns about cognitive effects, tolerance, dependence, and addiction. Misuse of opioids is prominent in patients with chronic pain and early recognition of misuse risk could help providers offer adequate patient care while implementing appropriate levels of monitoring to reduce aberrant drug-related behaviors. Many persons with chronic pain also have significant medical and psychiatric comorbidities that affect treatment decisions. Neuropsychologists can play an important role in the identification of psychological and social dysfunction and in matching personal characteristics to effective interventions as part of a multidisciplinary approach to pain management. The assessment of different domains using semi-structured interviews, sensory and neuropsychological testing, and standardized self-report measures permits identification of somatosensory, emotional, cognitive, behavioral, and social issues in order to facilitate treatment planning. In this review we discuss opioid abuse and misuse issues that often arise in the treatment of patients with chronic pain, and present an overview of assessment and treatment strategies that can be effective in improving outcomes associated with the use of prescription opioids for pain. Finally we briefly discuss the effect of opiate analgesics on cognition and review some intervention strategies for chronic pain patients.

A physician-driven solution--the Association for Medical Ethics, the Physician Payment Sunshine Act, and ethical challenges in pain medicine

The practice of contemporary pain medicine is laced with a number of significant ethical challenges. Considerable difficulties include the overutilization of interventional procedures, the application of under-evidenced treatment modalities, and potentially superfluous opioid prescribing. As with many other fields in medicine, including orthopedic surgery, relationships with industry are both common and pervasive, and influence our medical practice through education, publications, and research. This article highlights these ethical challenges and broaches several physician-driven solutions: The Association for Medical Ethics, the Physicians Payment Sunshine inspired by it, and other non-legislative reforms are discussed.