Drugs for chronic pain in children: a commentary on clinical practice and the absence of evidence

Diabetic neuropathy in children and youth: New and emerging risk factors

Pediatric neuropathy attributed to metabolic dysfunction is a well-known complication in children and youth with type 1 diabetes. Moreover, the rise of obesity and in particular of type 2 diabetes may cause an uptick in pediatric neuropathy incidence. However, despite the anticipated increase in neuropathy incidence, pathogenic insights and strategies to prevent or manage neuropathy in the setting of diabetes and obesity in children and youth remain unknown. Data from adult studies and available youth cohort studies are providing an initial understanding of potential diagnostic, management, and preventative measures in early life. This review discusses the current state of knowledge emanating from these efforts, with particular emphasis on the prevalence, clinical presentation, diagnostic approaches and considerations, and risk factors of neuropathy in type 1 and type 2 diabetes in children and youth. Also highlighted are current management strategies and recommendations for neuropathy in children and youth with diabetes. This knowledge, along with continued and sustained emphasis on identifying and eliminating modifiable risk factors, completing randomized controlled trials to assess effectiveness of strategies like weight loss and exercise, and enhancing awareness to support early detection and prevention, are pertinent to addressing the rising incidence of neuropathy associated with diabetes and obesity in children and youth.

Outcomes of the Pediatric Development Plan of Tapentadol

The opioid analgesic tapentadol was the first pain medication to be developed for the treatment of pain in children under a formal process established by the regulatory authorities. This article summarizes the outcomes of the pediatric development program for tapentadol across the entire age range from birth (including neonates) to adolescents <18 years of age. In addition, the challenges experienced when designing and conducting the pediatric tapentadol clinical trials as well as the interactions with the regulatory authorities are discussed. As a first outcome, the oral solution of tapentadol was authorized in the EU in 2018 as a new treatment option in the hospital setting for moderate to severe acute pain in children from 2 to <18 years of age.

Beyond Amitriptyline: A Pediatric and Adolescent Oriented Narrative Review of the Analgesic Properties of Psychotropic Medications for the Treatment of Complex Pain and Headache Disorders

Children and adolescents with recurrent or chronic pain and headache are a complex and heterogenous population. Patients are best served by multi-specialty, multidisciplinary teams to assess and create tailored, individualized pain treatment and rehabilitation plans. Due to the complex nature of pain, generalizing pharmacologic treatment recommendations in children with recurrent or chronic pains is challenging. This is particularly true of complicated patients with co-existing painful and psychiatric conditions. There is an unfortunate dearth of evidence to support many pharmacologic therapies to treat children with chronic pain and headache. This narrative review hopes to supplement the available treatment options for this complex population by reviewing the pediatric and adult literature for analgesic properties of medications that also have psychiatric indication. The medications reviewed belong to medication classes typically described as antidepressants, alpha 2 delta ligands, mood stabilizers, anti-psychotics, anti-sympathetic agents, and stimulants.

A Secondary Analysis of Integrated Pediatric Chronic Pain Services Related to Cost Savings

Youth with chronic pain have high healthcare utilization and associated costs. Research supports integrated treatment; though, it's unclear which treatments are used and cost-effective. This study expands on work that found reduced service use and cost savings following participation in an outpatient integrated pediatric pain clinic. We explored which services were commonly used and which individual (psychotherapy, medication management, acupuncture, massage, biofeedback) and/or combinations of services were associated with service use reduction and cost savings. Medication management and psychotherapy were more common than complementary integrative medicine (CIM) services. Massage services were associated with reduced inpatient costs. There were trends of fewer emergency department visits for participants who received CIM services in addition to medication management and psychotherapy, and more visits for those with biofeedback. Findings suggest that a more detailed examination of service utilization is needed to better understand cost outcomes related to the integrated treatment of pediatric chronic pain.

Pain Management In Pediatric Patients With Postural Orthostatic Tachycardia Syndrome: Current Insights

Pediatric patients with postural orthostatic tachycardia syndrome (POTS) often present with co-occurring struggles with chronic pain (POTS+pain) that may limit daily activities. POTS is a clinical syndrome characterized by orthostatic symptoms and excessive postural tachycardia without orthostatic hypotension. Active research from the medical and scientific community has led to controversy over POTS diagnosis and treatment, yet patients continue to present with symptoms associated with POTS+pain, making treatment recommendations critical. This topical review examines the literature on diagnosing and treating pediatric POTS+pain and the challenges clinicians face. Most importantly, clinicians must employ an interdisciplinary team approach to determine the ideal combination of pharmacologic (e.g., fludrocortisone), non-pharmacologic (e.g., physical therapy, integrative medicine), and psychological (e.g., cognitive behavioral therapy, psychoeducation) treatment approaches that acknowledge the complexity of the child's condition, while simultaneously tailoring these approaches to the child's personal needs. We provide recommendations for treatment for youth with POTS+pain based on the current literature.

The challenge of developing pain medications for children: therapeutic needs and future perspectives

It is broadly accepted that children of all age groups including (preterm) neonates and young infants can perceive pain and that there is an absolute need to treat their pain safely and effectively. The approved treatment options for children, particularly (preterm) neonates and young infants, are very limited with only a few medications specifically labelled for this population. This article presents the challenges of developing pain medications for children. A short overview gives information on pain in children, including pain perception, prevalence of pain and the long-term consequences of leaving pain untreated in this vulnerable population. Current pain management practices are briefly discussed. The challenges of conducting pediatric clinical trials in general and trials involving analgesic medications in particular within the regulatory framework available to develop these medications for children are presented. Emphasis is given to the operational hurdles faced in conducting a pediatric clinical trial program. Some suggestions to overcome these hurdles are provided based on our experience during the pediatric trial program for the strong analgesic tapentadol used for the treatment of moderate to severe acute pain.

Opioid Prescribing and Polypharmacy in Children with Chronic Musculoskeletal Pain

OBJECTIVE

Thirty percent of adults with fibromyalgia receive an opioid, but the prevalence of opioid prescribing in pediatric chronic musculoskeletal pain is unknown. The aims of this study were to determine the prevalence of and factors associated with opioid exposure and polypharmacy among children with chronic musculoskeletal pain.

METHODS

In this retrospective cohort study using health care claims data from 2000 to 2013, the index date was the first ICD-9 code 729.1. Included subjects were ≥ 2 and < 18 years old at the index date with two or more codes within 12 months and 18 months of continuous enrollment. Subjects with burns, sickle cell disease, or malignancy were excluded. Opioid exposure was defined as one or more prescriptions within six months before or any time after the index date. Polypharmacy was considered minor (2-4 medications) or major (≥5 medications).

RESULTS

Of 25,321 included subjects, 20% received an opioid and 26% experienced minor polypharmacy. Opioid exposure was associated with female sex (odds ratio [OR] = 1.27, P < 0.01), Caucasian race (OR = 1.27, P < 0.01), hospitalization (OR = 1.20, P < 0.01), and visit with anesthesiology (OR = 1.97, P < 0.01) or orthopedics (OR = 1.09, P < 0.05). Mental health codes were associated with decreased odds of opioid exposure (all P < 0.05). Children seen by a chiropractor or physiatrist had a reduced odds of receipt of an opioid (OR = 0.42 and 0.84, respectively, both P < 0.01).

CONCLUSIONS

Twenty percent of children with chronic musculoskeletal pain received an opioid. Twenty-six percent experienced polypharmacy, with the majority receiving 2-4 medications. Increased availability of psychological and nonpharmacologic services are potential strategies to reduce opioid exposure.

Chronic non-cancer pain in children: we have a problem, but also solutions

Chronic non-cancer pain in children and adolescents has been described as "a modern public health disaster" that has generated significant medical and economic burdens within society. Seen as a disease in its own right, chronic pain has short and long-term consequences that impact not only the patient's health but also that of friends and families, due to significant parenting stress and disruptions in family life and structure. The evidence supporting pharmacological treatments and interventional procedures is limited, and no single strategy has been shown to be completely effective in children with chronic non-cancer pain. Therefore, considering the multifactorial nature of chronic pain, these patients should be treated with a multidisciplinary, balanced approach that seeks a primary outcome of improved functioning rather than of pain reduction. Using a bio-psycho-social approach, a multidisciplinary team, including a physiotherapist, nurse, social worker, psychologist, and physician, has been effective in achieving this outcome of improved functioning in children and adolescents with chronic pain. In this review, we discuss the impact, associated conditions, and evolution of chronic pain, along with the crucial role of every member of a multidisciplinary chronic pain clinic involved in the care of the children and adolescents with chronic non-cancer pain.

The research gap in chronic paediatric pain: A systematic review of randomised controlled trials

BACKGROUND AND OBJECTIVE

Chronic pain is associated with significant functional and social impairment. The objective of this review was to assess the characteristics and quality of randomized controlled trials (RCTs) evaluating pain management interventions in children and adolescents with chronic pain.

METHODS

We performed a systematic search of PubMed, Embase and the Cochrane Library up to July 2017. We included RCTs that involved children and adolescents (3 months-18 years) and evaluated the use of pharmacological or non-pharmacological intervention(s) in the context of pain persisting or re-occurring for more than 3 months. Methodological quality was evaluated using the Cochrane Risk of Bias (ROB) Tool.

RESULTS

A total of 58 RCTs were identified and numbers steadily increased over time. The majority were conducted in single hospital institutions, with no information on study funding. Median sample size was 47.5 participants (Q1,Q3: 32, 70). Forty-five percent of RCTs included both adults and children and the median of the mean ages at inclusion was 12.9 years (Q1,Q3: 11, 15). Testing of non-pharmacological interventions was predominant and only 5 RCTs evaluated analgesics or co-analgesics. Abdominal pain, headache/migraine and musculoskeletal pain were the most common types of chronic pain among participants. Methodological quality was poor with 90% of RCTs presenting a high or unclear ROB.

CONCLUSIONS

Evaluation of analgesics targeting chronic pain relief in children and adolescents through RCTs is marginal. Infants and children with long-lasting painful conditions are insufficiently represented in RCTs. We discuss possible research constraints and challenges as well as methodologies to circumvent them.

SIGNIFICANCE

There is a substantial research gap regarding analgesic interventions for children and adolescents with chronic pain. Most clinical trials in the field focus on the evaluation of non-pharmacological interventions and are of low methodological quality. There is also a specific lack of trials involving infants and children and adolescents with long-lasting diseases.

Fibromyalgia: Treating Pain in the Juvenile Patient

Presently, evidence for the efficacy of medications for the treatment of juvenile fibromyalgia syndrome (JFMS) is limited. While there are medications approved by the US Food and Drug Administration (duloxetine, milnacipran and pregabalin) for adults with fibromyalgia syndrome, there are none for the treatment of JFMS. A variety of medications have been prescribed for the treatment of JFMS, including (but not limited to) non-opioid analgesics, opioids, anticonvulsants, antidepressants, and muscle relaxants. Psychological therapies, most prominently cognitive behavioral therapy, are the most evidenced-based treatment modalities for JFMS. A multidisciplinary approach, combining pharmacological, behavioral and exercise-based modalities is currently the standard of care for JFMS. In the future, more stringent randomized, controlled trials with longer follow-up periods are needed in order to determine the long-term efficacy and safety of medications in the treatment of JFMS. Additionally, improved recognition of JFMS will allow for better patient recruitment to permit for adequately powered study designs.

[Pain syndrome of the musculoskeletal system in children and adolescents]

Chronic pain syndromes in children and adolescents are defined as continuous or recurrent pain without an underlying causative diagnosis and lasting for more than 3 months. It is estimated that every fourth child in Germany suffers from chronic pain with every twentieth suffering from extreme recurrent pain. The incidence of chronic pain in children and adolescents is increasing with headache, abdominal pain and musculoskeletal pain being the most frequent. The quality of life declines not only due to the pain but to relieving postural and psychological factors, such as fear and sadness. School attendance, social activities and hobbies are mostly affected. This review summarizes the background of chronic pain syndromes and introduces a multimodal therapeutic approach.

Current experience of spinal neuromodulation in chronic pain: Is there a role in children and young people?

INTRODUCTION

Chronic pain in children has been an under-recognized problem compared to adult pain. The aim of management is to help children and their families cope with the symptoms rather than a cure. Current medical treatments to reduce pain intensity are often short lived, poorly tolerated or ineffective.

RESULTS

The use of electrical stimulation to treat pain is the current basis of modern Neuromodulation at the spinal cord and has been well established as spinal cord stimulation in adult practice. This involves placement of an epidural electrode connected to a subcutaneous implanted pulse generator. The electrode generates an electrical field at the dorsal columns of the spinal cord that inhibits pain pathways. Randomised controlled trials have demonstrated efficacy in neuropathic pain states such as the failed back surgery syndrome and complex regional pain syndrome.

CONCLUSION

Despite its initial expense, Spinal cord stimulation is a cost effective therapy in the long term and has the advantages of being a minimally invasive therapy and reversible.

Psychological Neuromodulatory Treatments for Young People with Chronic Pain

The treatment of young people with chronic pain is a complex endeavor. Many of these youth do not obtain adequate relief from available interventions. Psychological neuromodulatory treatments have been shown to have potential benefit for adults with chronic pain. Here, we review and summarize the available information about the efficacy of three promising psychological neuromodulatory treatments-neurofeedback, meditation and hypnosis-when provided to young people with chronic pain. A total of 16 articles were identified and reviewed. The findings from these studies show that hypnotic treatments are effective in reducing pain intensity for a variety of pediatric chronic pain problems, although research suggests variability in outcomes as a function of the specific pain problem treated. There are too few studies evaluating the efficacy of neurofeedback or meditation training in young people with chronic pain to draw firm conclusions regarding their efficacy. However, preliminary data indicate that these treatments could potentially have positive effects on a variety of outcomes (e.g., pain intensity, frequency of pain episodes, physical and psychological function), at least in the short term. Clinical trials are needed to evaluate the effects of neurofeedback and meditation training, and research is needed to identify the moderators of treatment benefits as well as better understand the mechanisms underlying the efficacy of all three of these treatments. The findings from such research could enhance overall treatment efficacy by: (1) providing an empirical basis for better patient-treatment matching; and (2) identifying specific mechanisms that could be targeted with treatment.

Recent trends in primary-care antidepressant prescribing to children and young people: an e-cohort study

BACKGROUND

Concerns relating to increased use of psychotropic medication contrast with those of under-treatment and under-recognition of common mental disorders in children and young people (CYP) across developed countries. Little is known about the indications recorded for antidepressant prescribing in primary care in CYP.

METHOD

This was an electronic cohort study of routinely collected primary-care data from a population of 1.9 million, Wales, UK. Poisson regression was undertaken to model adjusted counts of recorded depression symptoms, diagnoses and antidepressant prescriptions. Associated indications were explored.

RESULTS

3 58 383 registered patients aged 6-18 years between 1 January 2003 and 31 December 2013 provided a total of 19 20 338 person-years of follow-up. The adjusted incidence of antidepressant prescribing increased significantly [incidence rate ratio (IRR) for 2013 = 1.28], mainly in older adolescents. The majority of new antidepressant prescriptions were for citalopram. Recorded depression diagnoses showed a steady decline (IRR = 0.72) while depression symptoms (IRR = 2.41) increased. Just over half of new antidepressant prescriptions were associated with depression (diagnosis or symptoms). Other antidepressant prescribing, largely unlicensed, was associated with diagnoses such as anxiety and pain.

CONCLUSION

Antidepressant prescribing is increasing in CYP while recorded depression diagnoses decline. Unlicensed citalopram prescribing occurs outside current guidelines, despite its known toxicity in overdose. Unlicensed antidepressant prescribing is associated with a wide range of diagnoses, and while accepted practice, is often not supported by safety and efficacy studies. New strategies to implement current guidance for the management of depression in CYP are required.

Pain Amplification Syndrome: A Biopsychosocial Approach

Pediatric neurologists frequently encounter patients who present with significant musculoskeletal pain that cannot be attributed to a specific injury or illness, which can often be defined as pain amplification syndrome (PAS). PAS in children and adolescents is the result of a heightened pain sensitivity pathway, which is intensified by significant biological, psychological, and social contributors. Appropriate assessment and multimodal intervention of PAS are crucial to treatment success, including neurology and behavioral health collaborative treatment plans to restore patient function and reduce pain perception. Pediatric neurologists are imperative in the identification of patients with PAS, providing the family assurance in diagnosis and validation of pain, and directing patients to the appropriate multidisciplinary treatment pathway.

Off-label use of duloxetine for pediatric neuropathic pain

Introduction

Duloxetine, a serotonin-norepinephrine reuptake inhibitor, has been used successfully for adults for the management of neuropathic pain syndromes. Pediatric data are needed because inadequate neuropathic pain management in children and adolescents results in lower psychosocial functioning, delayed development, and decreased quality of life. We aim to describe a case series on the use of duloxetine for the management of symptoms associated with chronic neuropathic pain syndromes in a pediatric population.

Methods

Data were collected in a naturalistic, consecutive, case report format, from a pediatric pain management clinic for children prescribed duloxetine for analgesia for a variety of neuropathic-type pain conditions. Follow-up data, including self-report of pain, and type and frequency of adverse reactions, were collected to describe the efficacy and safety of duloxetine.

Results

Duloxetine was prescribed for the management of self-reported average pain scores of greater than 5 out of 10 on the Faces Pain Scale–Revised for pain that was resistant to other medications. Each of these patients had comorbid psychiatric diagnoses. Reduction in pain following duloxetine therapy was not universal, and all patients discontinued duloxetine therapy prematurely because of adverse effects.

Conclusion

Further evidence is needed to demonstrate the efficacy and safety of duloxetine for use in pediatric populations with neuropathic components to their pain. Based on our experience, we suggest considering its use only after failure of other agents. The best management of a pediatric patient's pain condition is likely accomplished through a combination of pharmacotherapy and nonpharmacotherapy interventions.

Pharmacological treatment of chronic non-cancer pain in pediatric patients

Chronic pain in children and young adults occurs frequently and contributes to early disability as well as personal and familial distress. A biopsychosocial approach to evaluation and treatment is recommended. Within this approach, there is a role for pharmacologic intervention. A variety of medications are used for chronic pain conditions in pediatric patients. Medication classes include anticonvulsants, muscle relaxants, antidepressants, opioids, local anesthetics, and anti-inflammatory drugs. Data is sparse, and most medications are used without condition-specific approval by national regulatory agencies such as the Food and Drug Administration in the US and the European Medicines Agency. In the absence of evidence on which to base practice, optimal drug therapy decisions rest on understanding proposed mechanisms of pain conditions, extrapolation from adult data-when such exists, and empirical and experiential knowledge. Drug delivery systems have evolved, and practitioners have to decide amongst not only medication classes, but also routes of delivery. Opioids are not recommended for use by non-pain specialists for the treatment of pediatric chronic pain, and even then the issues are more complex than can be addressed here. This article reviews the major medications used for pediatric chronic pain conditions.

A pain research agenda for the 21st century

Chronic pain represents an immense clinical problem. With tens of millions of people in the United States alone suffering from the burden of debilitating chronic pain, there is a moral obligation to reduce this burden by improving the understanding of pain and treatment mechanisms, developing new therapies, optimizing and testing existing therapies, and improving access to evidence-based pain care. Here, we present a goal-oriented research agenda describing the American Pain Society's vision for pain research aimed at tackling the most pressing issues in the field.

PERSPECTIVE

This article presents the American Pain Society's view of some of the most important research questions that need to be addressed to advance pain science and to improve care of patients with chronic pain.

Presentation and management of chronic pain

Chronic pain is an important clinical problem affecting significant numbers of children and their families. The severity and impact of chronic pain on everyday function is shaped by the complex interaction of biological, psychological and social factors that determine the experience of pain for each individual, rather than a straightforward reflection of the severity of disease or extent of tissue damage. In this article we present the research findings that strongly support a biopsychosocial concept of chronic pain, describe the current best evidence for management strategies and suggest a common general pathway for all types of chronic pain. The principles of management of some of the most important or frequently encountered chronic pain problems in paediatric practice; neuropathic pain, complex regional pain syndrome (CRPS), musculoskeletal pain, abdominal pain and headache are also described.

Bidirectional associations between pain and physical activity in adolescents

OBJECTIVES

The objectives were to: (1) examine temporal relationships between pain and activity in youth, specifically, whether physical activity affects pain intensity and whether intensity of pain affects subsequent physical activity levels on a daily basis, and (2) examine clinical predictors of this relationship.

METHODS

Participants were 119 adolescents (59 with chronic pain and 60 healthy) aged 12 to 18 years, 71% female. Adolescents completed 10 days of actigraphic monitoring of physical activity and daily electronic diary recordings of pain intensity, medication use, sleep quality, and mood. Linear mixed models assessed daily associations among physical activity and pain. Daily mean (average count/min) and peak (highest daily level) activity were used for analyses. Medication use, sleep quality, and mood ratings were included as covariates, and age, sex, and body mass index percentile were adjusted for.

RESULTS

Higher pain intensity was associated with lower peak physical activity levels on the next day (t641=-2.25, P=0.03) and greater medication use predicted lower mean physical activity levels the same day (t641=-2.10, P=0.04). Higher mean physical activity levels predicted lower pain intensity ratings at the end of the day (t705=-2.92, P=0.004), but only in adolescents with chronic pain.

DISCUSSION

Youth experiencing high pain intensity limit their physical activity level on a day-to-day basis. Activity was related to subsequent pain intensity, and may represent an important focus in chronic pain treatment. Further study of the effect of medications on subsequent activity is needed.

Daytime and nighttime sleep patterns in adolescents with and without chronic pain

OBJECTIVE

The aims of the current study were to characterize daytime and nighttime sleep patterns of adolescents with chronic pain, and to compare their sleep patterns to a healthy age- and sex-matched cohort.

METHODS

Sixty-one adolescents from a pain clinic and 60 age- and sex-matched youth from the community (mean age = 15.07; 69% female) participated. Participants underwent 10 days of actigraphic sleep monitoring to assess total sleep time (minutes of estimated sleep at night), wake minutes after initial sleep onset, sleep efficiency, and occurrence of sleep during the day.

RESULTS

Adolescents with chronic pain and healthy youth had similar nighttime sleep patterns (total sleep time, wake minutes after initial sleep onset, and sleep efficiency). However, adolescents with chronic pain spent more time sleeping during the day than their healthy peers. Longer daytime sleep was associated with more activity limitations in youth with chronic pain.

CONCLUSIONS

Although previous research using self-report methodology has indicated that adolescents with chronic pain commonly endorse poor sleep, findings from the current study suggest that these complaints may not be explained by differences in nighttime sleep patterns as measured by actigraphy. Use of multidimensional sleep assessment may help to understand the potential impact of sleep on chronic pain in adolescents.