Chronic Pain and Obesity Within a Pediatric Interdisciplinary Pain Clinic Setting: A Preliminary Examination of Current Relationships and Future Directions

Adolescent predictors of young adult pain and health outcomes: results from a 6-year prospective follow-up study

ABSTRACT

Adolescent chronic pain may lead to persistent disability and long-term health impairments in adulthood. However, our understanding of which youth are more likely to experience adverse outcomes remains limited. To address this gap, this longitudinal cohort study examined adolescent predictors of various dimensions of young adult health and functioning, including pain, physical health, depression, anxiety, social isolation, and sleep disturbance. As part of a previous clinical trial, we recruited a cohort of adolescents (ages 11-17 years, M age = 14 years) with non-disease-related chronic pain from 15 tertiary pain clinics in North America. Approximately 6 years later, 229 of the original 273 individuals (81% participation rate) completed a follow-up survey as young adults (ages 18-25 years, M age = 21 years). At the young adult follow-up, 73% reported continued chronic pain, with two-thirds experiencing moderate-to-severe pain interference. Youth reported several adverse health outcomes, including below-average physical health (37%), clinically elevated depression (42%), clinically elevated anxiety (48%), and sleep disturbances (77%). Multivariate regression analyses controlling for sociodemographic characteristics revealed that higher pain intensity, more pain locations, lower sleep quality, and greater anxiety symptoms in adolescence predicted worse pain outcomes in young adulthood. Moreover, lower sleep quality, greater anxiety symptoms, and worse family functioning predicted worse physical and psychosocial health in adulthood. These findings represent an important first step toward identifying ways to optimize psychological pain interventions. Tailored psychological pain interventions can directly target adolescent vulnerabilities, including mood, sleep, and family risk factors, with the potential to disrupt a lifelong trajectory of pain and suffering.

The Rating of Perceived Exertion-Pediatric (RPE-P) Scale: Preliminary Validation

Physical activity is critical to functional rehabilitation for youth with chronic pain, which may be especially true for those with co-occurring obesity. To facilitate the development of physical activity interventions for youth with chronic pain, the newly developed "Rating of Perceived Exertion-Pediatric" scale was modeled after the widely used pain numeric rating scale-11. This study is an initial evaluation of the scale in a sample of adolescents (n = 157, 13-17 years, 51% female) with four subgroups: (1) healthy controls (healthy weight/no pain); (2) chronic pain/healthy weight; (3) obese (no pain); (4) chronic pain/obese. Participants rated perceived exertion using the new scale and the Borg 6-20 Scale of Perceived Exertion while holding a three-minute yoga pose (Warrior II). In the whole sample, the Perceived Exertion-Pediatric scale showed good concurrent (p < 0.001), convergent (all ps < 0.05), discriminant (p = 0.431), and known-groups validity (all ps < 0.05). The chronic pain subgroup also showed good concurrent (p < 0.001), mixed convergent (ps < 0.001 to 0.315), and good discriminant validity (p = 0.607). Limitations include the restricted age range, lack of diversity, and lack of test-retest reliability. The RPE-P shows promise as an assessment tool for perceived exertion in adolescents with and without chronic pain.

Lipid signatures of chronic pain in female adolescents with and without obesity

BACKGROUND

Chronic pain in adolescence is associated with diminished outcomes, lower socioeconomic status in later life, and decreased family well-being. Approximately one third of adolescents with chronic pain have obesity compared to the general population. In obesity, lipid signals regulate insulin sensitivity, satiety, and pain sensation. We determined whether there is a distinct lipid signature associated with chronic pain and its co-occurrence with obesity in adolescents.

METHODS

We performed global lipidomics in serum samples from female adolescents (N = 67, 13-17 years old) with no pain/healthy weight (Controls), chronic pain/healthy weight (Pain Non-obese), no pain/obesity (Obese), or chronic pain/obesity (Pain Obese).

RESULTS

The Pain Non-obese group had lipid profiles similar to the Obese and Pain Obese groups. The major difference in these lipids included decreased lysophosphatidylinositol (LPI), lysophosphatidylcholine (LPC), and lysophosphatidylethanolamine (LPE) in the three clinical groups compared to the Control group. Furthermore, ceramides and sphingomyelin were higher in the groups with obesity when compared to the groups with healthy weight, while plasmalogens were elevated in the Pain Obese group only.

CONCLUSIONS

Serum lipid markers are associated with chronic pain and suggest that specific lipid metabolites may be a signaling mechanism for inflammation associated with co-occurring chronic pain and obesity.

Effects of Weight and Pain on Physical Activity: Insights from the Lived Experiences of Youth with Co-Occurring Chronic Pain and Obesity

Objective: Pediatric obesity and chronic pain are each associated with an increased risk for numerous poor physical and mental health outcomes. Co-occurring chronic pain and obesity (CPO) result in greater functional disability compared with either condition alone. The aim of the present study was to use qualitative methods to better understand the challenges experienced by adolescents with CPO, with a specific focus on physical activity. Methods: Semistructured interviews were conducted with 13 youth with CPO. Participants were questioned about pain, physical activity, coping strategies, and the perceived relationship between weight and pain. Interviews were audiorecorded, transcribed, and analyzed according to Interpretative Phenomenological Analysis. Results: Superordinate themes expressed by youth included: Impact of Chronic Pain on Relationships, Impact of Pain on Self-Perception, Using Food to Cope with Pain, Perceived Relationship between Pain and Weight after Onset of Pain, Attitudes toward Physical Activity, Barriers to Physical Activity, and Supports to Physical Activity. Conclusions: Participants identified challenges associated with CPO. Notably, participants identified pain as a greater barrier to exercise than weight, implicating the salience of chronic pain in the lives of youth with CPO. Furthermore, participants identified a desire to be more physically active, yet discussed struggles and concerns about attempts to increase their physical activity and indicated a desire for guidance about being more active. This study highlights the complexities of the relationship between CPO and underscores the importance of providers collaboratively working with patients to develop a practical plan to resume movement and physical activity.

Preliminary Validation of the Pain Burden Inventory in a Pediatric Chronic Pain Population

OBJECTIVE

To determine the preliminary reliability and validity of the Pain Burden Inventory-Youth (PBI-Y), a 7-item measure of the impact of chronic pain in adolescents with chronic pain that was, initially validated in youth with sickle cell disease.

MATERIALS AND METHODS

A retrospective chart review of 130 patients presenting to an interdisciplinary pain clinic were examined with 98 (mean age=14.49; 66% female) comprising the final sample. Demographic information as well as adolescent and parent self-reported measures were examined.

RESULTS

Youth reported a variety of pains including abdominal pain, headaches, back pain, and amplified musculoskeletal pain. The PBI-Y demonstrated strong internal reliability (α=0.792) and strong cross-informant concordance (r=0.822; P=0.000). Good construct validity was seen where higher scores on the PBI-Y were correlated with higher scores of (1) functional disability (r=0.689; P=0.000), (2) pain catastrophizing (r=0.494; P=0.000), (3) pain frequency days (r=0.526; P=0.000), (4) usual pain intensity (r=0.467; P=0.000), and (5) the worst pain intensity (r=0.485; P=0.000). Similar results were seen with caregiver assessments. Neither caregiver nor youth reports differed based on the sex or age of the child.

DISCUSSION

The results support the psychometric properties of a brief self-report measure of pain impact in a pediatric chronic pain population. This measure may have great utility for clinicians caring for youth with chronic pain.

Biomarkers of Allostatic Load as Correlates of Impairment in Youth with Chronic Pain: An Initial Investigation

Pediatric chronic pain is common and responsible for significant healthcare burden. However, the mechanisms underlying the development and/or maintenance of pediatric chronic pain remain poorly understood. Allostatic load (AL), or wear and tear on the nervous system following significant or prolonged stress, has been proposed to play a role in the maintenance of chronic pain, but minimal research has examined this possibility. This gap in research is particularly notable given the high exposure to adverse childhood experiences (ACEs; abuse/neglect, etc.) and psychological stress in this population. Accordingly, the current study aimed to preliminarily examine the measurement of AL in a treatment-seeking pediatric pain population. Biomarkers were collected during an already scheduled new patient pain evaluation and included salivary cortisol, dehydroepiandrosterone (DHEA), and C-reactive protein, in addition to waist-hip ratio, body-mass index, and blood pressure. A total of 61 children and adolescents with chronic pain (Mage = 14.47 years; 88.5% female and white/Caucasian) completed study procedures and were included in analyses. Preliminary results indicated that a multifactorial AL composite is feasible to assess for in a tertiary pain treatment setting and that over 50% of youth with chronic pain were classified as high risk for AL (two or more risk factors). Further, it was found that individual AL risk factors were significantly associated with functional disability and that AL may moderate the association between psychosocial and functional outcomes. Given the pilot nature of this study, results should be used to inform future investigations with larger and more diverse pediatric pain samples.

Helping Children with Obesity "Move Well" To Move More: An Applied Clinical Review

ABSTRACT

Children with obesity experience musculoskeletal pain and reduced physical function and well-being, which collectively impact their fitness, strength, motor skills, and even their ability to undertake simple tasks, like walking and climbing stairs. Disrupting obesity-related disability may be critical to increasing children's physical activity. Thus, barriers to movement should be considered by health practitioners to improve the efficacy of prescribed physical activity. This applied clinical review highlights key subjective and objective findings from a hypothetical case scenario, linking those findings to the research evidence, before exploring strategies to enhance movement and increase physical activity.

Pain, eating behavior, and weight outcomes in adolescent girls

OBJECTIVE

In adults, pain is prospectively associated with overweight/obesity and concurrently associated with dysregulated eating, with evidence for stronger associations in women than men. This study aimed to evaluate whether similar associations among pain response, BMI, and loss of control (LOC) eating are also evident in adolescent girls.

METHOD

Girls (n = 202) completed the cold pressor test (CPT) at age 10, and BMI and LOC eating were assessed annually from ages 10-16 years. Generalized linear models were used to test associations between pain tolerance (total immersion time) and threshold (latency to highest pain rating), and changes in BMI and LOC eating.

RESULTS

Lower pain tolerance and threshold at age 10 were associated with increases in LOC eating from age 10 to 16 (tolerance: B < -.01, SE < .01, p = .005; threshold: B = -.03, SE = .01, p = .0118). No significant associations were observed between pain tolerance/threshold and increasing BMI.

DISCUSSION

Pain responsivity in childhood is associated with increases in dysregulated eating from childhood to adolescence. These findings provide support for the early development of an interface between pain and eating behaviors.

Investigating the Relationship between Body Mass Index and Pain in the Spine in Children or Adolescents: A Systematic Review

Background: Neck pain (NP), back pain (BP), and low back pain (LBP) are generally defined as "pain in the spine." With the increasing prevalence of childhood obesity, secondary problems such as pain in the spine have arisen. The purpose of this review was to investigate the relationship between body mass index (BMI) and pain in the spine in children or adolescents. Methods: Publications were searched in PubMed, Web of Science, Scopus, and Google Scholar databases up to December 12, 2020. The search strategy in the database consisted of free text words and MeSH terms. Results: Twelve studies were reviewed. It was determined that different methods were used in all 12 studies to evaluate pain. In the evaluation of overweight/obesity, these studies performed BMI assessment by dividing body weight in kilograms by height squared. Five studies showed a relationship between LBP and BMI, two studies showed a relationship between BP and BMI, and two studies showed a relationship between NP and BMI. Conclusions: The review shows that there is a relationship between BMI and pain in the spine, especially LBP. There may be factors affecting this condition such as mechanical loading and hormonal metabolic activity in childhood and adolescence. Different methods are used in the studies in literature for the assessment pain in the spine and BMI, overweight, and obesity.

Practical Challenges-Use of Paracetamol in Children and Youth Who are Overweight or Obese: A Narrative Review

Worldwide, > 380 million children and adolescents are overweight or obese, including 41 million children aged < 5 years. Obesity can change the pharmacokinetic properties of drugs by altering their distribution, metabolism, and elimination. Thus, children who are overweight or obese are at increased risk for receiving inappropriate doses of commonly used drugs, which can result in treatment failure, adverse events, and/or drug toxicity. This review analyzes available data on paracetamol dosing for pain and fever in children and adolescents who are overweight or obese to identify gaps and challenges in optimal dosing strategies. Literature searches using Medline, Embase, and ClinicalTrials.gov were conducted to identify English-language articles reporting paracetamol pharmacokinetics, dosing practices, and guidelines in children and adolescents who are overweight or obese. Of 24 relevant studies identified, 20 were specific to overweight/obese individuals and 15 were specific to children and/or adolescents. Data on paracetamol pharmacokinetics in children and adolescents who are overweight or obese are lacking, and there is no high-quality evidence to guide paracetamol prescribing practices in these patients. Adult data have been extrapolated to pediatric populations; however, extrapolation does not address differences in paracetamol metabolism in adults versus children; the efficacy and safety effects of such differences are unknown. Given the growing worldwide prevalence of obesity in children and adolescents and the likelihood that paracetamol use in this population will increase accordingly, obesity-specific pediatric dosing guidelines for paracetamol are urgently needed. High-quality research is necessary to inform such guidelines.

Serum soluble urokinase plasminogen activator receptor in adolescents: interaction of chronic pain and obesity

Pediatric chronic pain is exacerbated by obesity. Serum soluble urokinase plasminogen activator receptor, a novel inflammation biomarker, was increased in obese adolescents with chronic pain indicating interactive inflammatory conditions.

Introduction:

Obesity in adolescents is increasing in frequency and is associated with short-term and long-term negative consequences that include the exacerbation of co-occurring chronic pain.

Objective:

To determine whether the interaction between chronic pain and obesity would be reflected in changes in serum soluble urokinase plasminogen activator receptor (suPAR) concentrations, a novel marker of systemic inflammation associated with obesity, insulin resistance, and cardiovascular disease.

Methods:

We measured serum suPAR levels in 146 adolescent males and females with no pain or obesity (healthy controls; n = 40), chronic pain with healthy weight (n = 37), obesity alone (n = 41), and the combination of chronic pain and obesity (n = 28).

Results:

Serum suPAR (median [interquartile range]) was not increased by chronic pain alone (2.2 [1.8–2.4] ng/mL) or obesity alone (2.2 [2.0–2.4] ng/mL) but was increased significantly with the combination of chronic pain and obesity (2.4 [2.1–2.7] ng/mL; P < 0.019). This finding confirms the proposition that pain and obesity are inflammatory states that display a classic augmenting interaction.

Conclusion:

We propose that measurement of serum suPAR can be added to the armamentarium of serum biomarkers useful in the evaluation of mechanisms of inflammation in adolescent obesity and chronic pain.

Obesity in Young Adulthood: The Role of Physical Activity Level, Musculoskeletal Pain, and Psychological Distress in Adolescence (The HUNT-Study)

The global obesity epidemic raises long-term health concerns which underline the importance of preventive efforts. We aimed to investigate individual and combined effects of common health problems in adolescence on the probability of obesity in young adulthood. This prospective population-based study included data from participants in the Nord-Trøndelag Health Study in Norway (Young-HUNT1 (1995–1997), age 13–19, baseline) who participated in HUNT3 as young adults 11 years later (age 23–31). Exposure variables at baseline included self-reported physical activity, musculoskeletal pain, and psychological distress. We examined associations between exposure variables and the main outcome of obesity in young adulthood (BMI ≥ 30 kg/m²) using univariate and multiple logistic regression, stratified by sex. Probabilities of obesity for given combinations of the exposure variables were visualized in risk matrixes. The study sample consisted of 1859 participants (43.6% boys). Higher probabilities of obesity in young adulthood were found across combinations of lower physical activity levels and presence of musculoskeletal pain in adolescence. Additional adverse effects of psychological distress were low. Proactive intervention strategies to promote physical activity and facilitate sports participation for all adolescents, whilst addressing musculoskeletal pain and its potential individual causes, could prove helpful to prevent development of obesity in young adulthood.

Quantitative Sensory Testing in Adolescents with Co-occurring Chronic Pain and Obesity: A Pilot Study

Factors such as gender, ethnicity, and age affect pain processing in children and adolescents with chronic pain. Although obesity has been shown to affect pain processing in adults, almost nothing is known about pediatric populations. The aim of this pilot study was to explore whether obesity alters sensory processing in adolescents with chronic pain. Participants were recruited from a chronic pain clinic (Chronic Pain (CP), n = 12 normal weight; Chronic Pain + Obesity (CPO), n = 19 overweight/obesity) and from an obesity clinic (Obesity alone (O), n = 14). The quantitative sensory testing protocol included assessments of thermal and mechanical pain thresholds and perceptual sensitization at two sites with little adiposity. The heat pain threshold at the hand was significantly higher in the CPO group than in either the CP or O groups. Mechanical pain threshold (foot) was significantly higher in the CPO group than the CP group. No differences were found on tests of perceptual sensitization. Correlations between experimental pain and clinical pain parameters were found for the CPO group, but not for the CP group. This preliminary study provides important lessons learned for subsequent, larger-scale studies of sensory processing for youth with co-occurring chronic pain and obesity.

Impact of Child and Maternal Weight on Healthcare Trainee Clinical Assessment Decision Making: A Virtual Human Study

BACKGROUND

Adult literature documents that healthcare providers rely on patient characteristics, such as age, race, and weight, when making clinical decisions. However, little research has examined these biases among pediatric populations. This study aimed to examine the impact of child and maternal weight and race on clinical decision-making of healthcare trainees in the context of a pediatric pain assessment using standardized virtual pediatric patients and mothers.

METHODS

Ninety-two healthcare trainees read a standardized clinical vignette describing a child with chronic pain, which was accompanied by eight virtual human (VH) scenes-each with a child and mother. Scenes varied by the dyad's race, child's weight status, and mother's weight status. For each scene, participants were asked to make six healthcare assessment ratings.

RESULTS

Participants rated children (M = 42.44 vs. 48.69; p < 0.001) and mothers (M = 51.06 vs. 65.31; p < 0.001) with obesity as being less likely to adhere to physician recommendations compared with healthy weight children and mothers. Child patients with obesity (M = 38.88 vs. 30.08; p < 0.001) and mothers with obesity (M = 49.71 vs. 43.71; p < 0.001) were also rated as bearing more responsibility for the child's health status compared with healthy weight peers.

CONCLUSIONS

This study provides evidence that child and mother weight can impact clinical decision-making, as well as for the utility of VH technology in studying decision-making among healthcare trainees and providers.

Peripheral Leptin Signaling Mediates Formalin-Induced Nociception

Accumulating evidence suggests that obesity is associated with chronic pain. However, whether obesity is associated with acute inflammatory pain is unknown. Using a well-established obese mouse model induced by a high-fat diet, we found that: (1) the acute thermal pain sensory threshold did not change in obese mice; (2) the model obese mice had fewer nociceptive responses in formalin-induced inflammatory pain tests; restoring the obese mice to a chow diet for three weeks partly recovered their pain sensation; (3) leptin injection induced significant phosphorylation of STAT3 in control mice but not in obese mice, indicating the dysmodulation of topical leptin-leptin receptor signaling in these mice; and (4) leptin-leptin receptor signaling-deficient mice (ob/ob and db/db) or leptin-leptin receptor pathway blockade with a leptin receptor antagonist and the JAK2 inhibitor AG 490 in wild-type mice reduced their nociceptive responses in formalin tests. These results indicate that leptin plays a role in nociception induced by acute inflammation and that interference in the leptin-leptin receptor pathway could be a peripheral target against acute inflammatory pain.