The journal of pain : official journal of the American Pain Society
-
Randomized Controlled Trial
Developmental data supporting simplification of self-report pain scales for preschool-age children.
Claims regarding the ability of preschool-age children to provide accurate self-reports using standard pain scales are not well supported by age-specific evidence. Responses of children younger than 5 years are often idiosyncratic and subject to biases. Simplifying the task of self-report of pain would make it more developmentally appropriate for 3- to 5-year-olds. A binary question is asked: "Does it hurt?" or an equivalent. If yes, a simplified scale is presented, comprising 3 categories representing low, medium, and high pain severity. Children aged 3 to 5 years (N = 184) were recruited from preschools and day care centers. Following parental consent and child assent, children were randomly assigned to use either the Faces Pain Scale-Revised or a 3-face scale preceded by a yes-no question to rate pain in 9 picture stories from the Charleston Pediatric Pain Pictures portraying no pain, moderate pain, and severe pain. The simplified pain rating task made no difference for 5-year-olds, whose mean scores were nearly identical using the 2 approaches. However, discrimination of the 3 levels of Charleston Pediatric Pain Pictures items was significantly better in 3- and 4-year-olds with the simplified task than with the Faces Pain Scale-Revised. Simplifying the task improved preschool-age children's ability to estimate pain intensity. ⋯ Standard self-report pain scales with 6 faces are confusing for many 3- and 4-year-olds. In basic preparatory research for future development of a preschool self-report pain scale, we simplified the task. This simplification made no difference for 5-year-olds but improved the performance of 3- and 4-year-olds.
-
Traumatic brain injury (TBI) is a leading cause of pediatric disability. Although persistent pain has been recognized as a significant postinjury complication, there is a paucity of data concerning the postinjury pain experience of youth. This study aimed to examine the prevalence of persistent pain in adolescents after TBI, identify risk factors for pain, and evaluate the impact of pain on adolescent health-related quality of life. Participants included 144 adolescents with mild to severe TBI who were followed over 36 months after injury. At 3-, 12-, 24-, and 36-month assessments, measures of pain intensity, depression, posttraumatic stress disorder, and health-related quality of life were completed by adolescents. Findings demonstrated that 24.3% of adolescents reported persistent pain (defined as usual pain intensity ≥3/10) at all assessment points after TBI. Female sex (odds ratio = 2.73, 95% confidence interval = 1.12-6.63) and higher levels of depressive symptoms at 3 months after injury (odds ratio = 1.26, 95% confidence interval = 1.12-1.43) were predictors of persistent pain at 36 months. Furthermore, mixed linear models indicated that early pain experience at 3 months following TBI was associated with a significantly poorer long-term health-related quality of life. ⋯ This is the first study to examine the prevalence of persistent pain over long-term follow-up in adolescents after TBI and its impact on health-related quality of life. These findings indicate that adolescents with TBI may benefit from timely evaluation and intervention to minimize the development and impact of pain.
-
The default mode network (DMN), a group of brain regions implicated in passive thought processes, has been proposed as a potentially informative neural marker to aid in novel treatment development. However, the DMN's internal connectivity and its temporal relationship (ie, functional network connectivity) with pain-related neural networks in chronic pain conditions is poorly understood, as is the DMN's sensitivity to analgesic effects. The current study assessed how DMN functional connectivity and its temporal association with 3 pain-related networks changed after rectal lidocaine treatment in irritable bowel syndrome patients. Eleven females with irritable bowel syndrome underwent a rectal balloon distension paradigm during functional magnetic resonance imaging in 2 conditions: natural history (ie, baseline) and lidocaine. Results showed increased DMN connectivity with pain-related regions during natural history and increased within-network connectivity of DMN structures under lidocaine. Further, there was a significantly greater lag time between 2 of the pain networks, those involved in cognitive and in affective pain processes, comparing lidocaine to natural history. These findings suggest that 1) DMN plasticity is sensitive to analgesic effects, and 2) reduced pain ratings via analgesia reflect DMN connectivity more similar to pain-free individuals. Findings show potential implications of this network as an approach for understanding clinical pain management techniques. ⋯ This study shows that lidocaine, a peripheral analgesic, significantly altered DMN connectivity and affected its relationship with pain-related networks. These findings suggest that the DMN, which is hypothesized to represent non-goal-oriented activity, is sensitive to analgesic effects and could be useful to understand pain treatment mechanisms.
-
Many pain syndromes are associated with abnormal proliferation of peripheral sensory fibers. We showed previously that angiotensin II, acting through its type 2 receptor (AT2), stimulates axon outgrowth by cultured dorsal root ganglion neurons. In this study, we assessed whether AT2 mediates nociceptor hyperinnervation in the rodent hind paw model of inflammatory pain. Plantar injection of complete Freund's adjuvant (CFA), but not saline, produced marked thermal and mechanical hypersensitivity through 7 days. This was accompanied by proliferation of dermal and epidermal PGP9.5-immunoreactive (ir) and calcitonin gene-related peptide-immunoreactive (CGRP-ir) axons, and dermal axons immunoreactive for GFRα2 but not tyrosine hydroxylase or neurofilament H. Continuous infusion of the AT2 antagonist PD123319 beginning with CFA injection completely prevented hyperinnervation as well as hypersensitivity over a 7-day period. A single PD123319 injection 7 days after CFA also reversed thermal hypersensitivity and partially reversed mechanical hypersensitivity 3 hours later, without affecting cutaneous innervation. Angiotensin II-synthesizing proteins renin and angiotensinogen were largely absent after saline but abundant in T cells and macrophages in CFA-injected paws with or without PD123319. Thus, emigrant cells at the site of inflammation apparently establish a renin-angiotensin system, and AT2 activation elicits nociceptor sprouting and heightened thermal and mechanical sensitivity. ⋯ Short-term AT2 activation is a potent contributor to thermal hypersensitivity, whereas long-term effects (such as hyperinnervation) also contribute to mechanical hypersensitivity. Pharmacologic blockade of AT2 signaling represents a potential therapeutic strategy aimed at biologic mechanisms underlying chronic inflammatory pain.
-
Review Meta Analysis
The relation between pain-related fear and disability: a meta-analysis.
Within a biopsychosocial framework, psychological factors are thought to play an important role in the onset and progression of chronic pain. The cognitive-behavioral fear-avoidance model of chronic pain suggests that pain-related fear contributes to the development and maintenance of pain-related disability. However, investigations of the relation between pain-related fear and disability have demonstrated considerable between-study variation. The main goal of the current meta-analysis was to synthesize findings of studies investigating cross-sectional associations between pain-related fear and disability in order to estimate the magnitude of this relation. We also tested potential moderators, including type of measure used, demographic characteristics, and relevant pain characteristics. Searches in PubMed and PsycINFO yielded a total of 46 independent samples (N = 9,579) that reported correlations between pain-related fear and disability among persons experiencing acute or chronic pain. Effect size estimates were generated using a random-effects model and artifact distribution method. The positive relation between pain-related fear and disability was observed to be moderate to large in magnitude, and stable across demographic and pain characteristics. Although some variability was observed across pain-related fear measures, results were largely consistent with the fear-avoidance model of chronic pain. ⋯ Results of this meta-analysis indicate a robust, positive association between pain-related fear and disability, which can be classified as moderate to large in magnitude. Consistent with the fear-avoidance model of chronic pain, these findings suggest that pain-related fear may be an important target for treatments intended to reduce pain-related disability.