A multidimensional appraisal of early menstrual pain experience.

BACKGROUND: Symptomatic dysmenorrhea is a global problem, affecting more than 40% of menstruating persons. Cross-sectional studies have implicated psychosocial, biological, and sensory factors in dysmenorrhea but the mechanisms are not fully understood. Only a few prospective longitudinal studies have evaluated such factors in relation to the emergence and course of dysmenorrhea at menarche. OBJECTIVE: This study aimed to describe the initial menstruation experience and to evaluate the association of premenarchal psychosocial and sensory factors with the intensity of dysmenorrhea during the period in the fourth month. STUDY DESIGN: This was a prospective cohort study of adolescents who completed premenarchal assessments and postmenarchal daily menstrual diaries for their first (n=149) and fourth month periods (n=114). They were recruited shortly before menarche and completed baseline assessments, including psychosocial questionnaires and experimental pain sensitivity (pressure testing, bladder provocation), and their parents completed related pain questionnaires. The relation between the hypothesized premenarchal factors and month 4 dysmenorrhea intensity was evaluated using Kruskal-Wallis and chi-square tests for low (<3 on a 0-10 scale) vs higher (≥3) menstrual pain groups based on maximal pain ratings recorded in a daily diary. RESULTS: Low levels of dysmenorrhea characterized the first (median, 1; interquartile range, 0-2) and fourth month periods (1; 0-3). Maximal pain ratings increased from the first to the fourth period (3; 1-5 vs 4; 1-6; P=.007). The distribution of dysmenorrhea was multimodal at month 4 with 31.6% of the participants having low levels of maximal pain (1; 0-1) and 68.4% having higher levels (5; 4-6; Hartigan's dip test P<.001). The baseline demographic, psychosocial, and parental pain characteristics were not associated with the development of worse dysmenorrhea. The baseline experimental pain sensitivity, based on pressure pain thresholds, did not differ between the low (15.7 N; 12.5-22.3) and higher (15.0 N; 10.9-21.4]) level dysmenorrhea groups. Baseline bladder pain at first urge also did not differ (low, 6; 0-20 vs higher, 7; 0-19). CONCLUSION: By their fourth month period, two-thirds of adolescents fell into the higher group for maximal dysmenorrhea, half reported some related impairments in physical activity, and one-seventh reported some related school absence. Premenarchal factors (experimental pain sensitivity, psychosocial profile, parental pain experience) linked to chronic pain emergence in the adult literature did not predict dysmenorrhea intensity, suggesting the dominant factor at menarche may be peripheral afferent activation. Further research is needed to understand the evolution of psychosocial and sensory mechanisms in the development and course of dysmenorrhea.

Twenty-year Outcomes of a Pediatric Chronic Abdominal Pain Cohort: Early Adulthood Health Status and Offspring Physical and Behavioral Health.

Chronic abdominal pain (CAP) represents a common pediatric primary pain disorder that can have long-term effects on physical and mental health into adulthood. Pediatric CAP and Control cohorts recruited in childhood (∼11 years old, T1) and then assessed in emerging adulthood (∼20 years old, T2) were evaluated again for health outcomes in early adulthood (∼30 years old, T3) for the current study. Further, the study evaluated the mental and physical health of offspring of participants who had become parents. Participants who agreed to enroll at T3 (CAP: n = 90, Control: n = 55) completed measures regarding current health, health-related quality of life (HRQoL), and their child's health when applicable. Results indicated close to 20% of the CAP cohort reported recurrent CAP across all 3 timepoints. Participants with current CAP reported poorer HRQoL compared to participants with remitted CAP who reported poorer HRQoL compared to Control participants. The CAP cohort reported higher health-related anxiety compared to the Control cohort regardless of current pain status. CAP compared to Control participants reported greater emotional problems and fewer conduct problems in their children. Longitudinal studies are needed to assess the developmental course of pediatric chronic pain and intergenerational pathways of risk and resilience. Perspective: This article evaluates patterns of chronic abdominal pain from childhood into early adulthood. Patients with pediatric chronic abdominal pain continue to present with health-related anxiety in adulthood and report greater emotional problems in offspring.

Multichannel magnetogastrogram: a clinical marker for pediatric chronic nausea.

Chronic nausea is a widespread functional disease in children with numerous comorbidities. High-resolution electrogastrogram (HR-EGG) has shown sufficient sensitivity as a noninvasive clinical marker to objectively detect distinct gastric slow wave properties in children with functional nausea. We hypothesized that the increased precision of magnetogastrogram (MGG) slow wave recordings could provide supplementary information not evident on HR-EGG. We evaluated simultaneous pre- and postprandial MGG and HR-EGG recordings in pediatric patients with chronic nausea and healthy asymptomatic subjects, while also measuring nausea intensity and nausea severity. We found significant reductions in postprandial dominant frequency and normogastric power, and higher levels of postprandial bradygastric power in patients with nausea in both MGG and HR-EGG. MGG also detected significantly lower preprandial normogastric power in patients. A significant difference in the mean preprandial gastric slow wave propagation direction was observed in patients as compared with controls in both MGG (control: 180 ± 61°, patient: 34 ±72°; P < 0.05) and HR-EGG (control: 240 ± 39°, patient: 180 ± 46°; P < 0.05). Patients also showed a significant change in the mean slow wave direction between pre- and postprandial periods in MGG (P < 0.05). No statistical differences were observed in propagation speed between healthy subjects and patients in either MGG or HR-EGG pre/postprandial periods. The use of MGG and/or HR-EGG represents an opportunity to assess noninvasively the effects of chronic nausea on gastric slow wave activity. MGG data may offer the opportunity for further refinement of the more portable and economical HR-EGG in future machine-learning approaches for functional nausea.NEW & NOTEWORTHY Pediatric chronic nausea is a difficult-to-measure subjective complaint that requires objective diagnosis, clinical assessment, and individualized treatment plans. Our study demonstrates that multichannel MGG used in conjunction with custom HR-EGG detects key pathological signatures of functional nausea in children. This quantifiable measure may allow more personalized diagnosis and treatment in addition to minimizing the cost and potential radiation associated with current diagnostic approaches.

Sex Moderates the Relationship Between Nausea Severity and Heart Rate Variability in Adolescents and Young Adults.

BACKGROUND: Nausea is a common complaint among children and is particularly prevalent in children with functional abdominal pain (FAP), with nearly half of children with FAP also endorsing nausea. Dysfunction of the autonomic nervous system, which can be indexed by heart rate variability (HRV), leads to abnormalities in gastric electrical activity that are associated with GI symptoms. AIMS: To evaluate that relationship between nausea severity and HRV in adolescents and young adults with a history of FAP and to assess for sex differences. METHODS: Participants were pediatric patients with a diagnosis of FAP who were recruited from a pediatric GI clinic between 1993 and 2007 for a prospective study of the course of FAP. Study analyses focused on the cross-sectional relationship between HRV, indexed by standard deviation of the R-R interval (SDRRI) and high-frequency (HF) power, and nausea severity collected during a follow-up visit in late adolescence and young adulthood. RESULTS: Controlling for age and BMI, a significant nausea by sex interaction emerged for both SDRRI and HF power. Tests of conditional effects of nausea by sex showed that the inverse relation between nausea severity and both SDRRI and HF was significant for females but not for males. CONCLUSIONS: This is the first study to evaluate the relationship between nausea severity and HRV. Greater nausea severity was associated with lower HRV in females but not in males. Further validation of these results may provide insight into novel treatment approaches for females with nausea that target vagal tone.

Noninvasive bladder testing of adolescent females to assess visceral hypersensitivity.

ABSTRACT: Excess pain after visceral provocation has been suggested as a marker for chronic pelvic pain risk in women. However, few noninvasive tests have been validated that could be performed readily on youth in early risk windows. Therefore, we evaluated the validity and reliability of a noninvasive bladder pain test in 124 healthy premenarchal females (median age 11, [interquartile range 11-12]), as previously studied in adult women. We explored whether psychosocial, sensory factors, and quantitative sensory test results were associated with provoked bladder pain and assessed the relation of bladder pain with abdominal pain history. Compared with findings in young adult females (age 21 [20-28]), results were similar except that adolescents had more pain at first sensation to void (P = 0.005) and lower maximum tolerance volume (P < 0.001). Anxiety, depression, somatic symptoms, and pain catastrophizing predicted provoked bladder pain (P's < 0.05). Bladder pain inversely correlated with pressure pain thresholds (r = -0.25, P < 0.05), but not with cold pressor pain or conditioned pain modulation effectiveness. Bladder pain was also associated with frequency of abdominal pain symptoms (r = 0.25, P = 0.039). We found strong retest reliability for bladder pain at standard levels of sensory urgency in 21 adolescents who attended repeat visits at 6 to 12 months (intraclass correlations = 0.88-0.90). Noninvasive bladder pain testing seems reproducible in adolescent females and may predict abdominal pain symptomatology. Confirmation of our findings and further investigation of the bladder test across menarche will help establish how visceral sensitivity contributes to the early trajectory of pelvic pain risk.

Place and Pain: Association Between Neighborhood SES and Quantitative Sensory Testing Responses in Youth With Functional Abdominal Pain.

OBJECTIVE: Neighborhood socioeconomic status (SES) is linked to self-reported pain severity and disability but its association with evoked pain responsiveness in individuals with chronic pain remains unclear. The present study examined relations between neighborhood SES, assessed through the area deprivation index (ADI), and static and dynamic pain response indices. It was hypothesized that youth with functional abdominal pain (FAP) living in lower SES neighborhoods would exhibit lower pain threshold, lower pain tolerance, and reduced conditioned pain modulation (CPM) compared to youth living in higher SES neighborhoods. METHODS: Participants were 183 youth with FAP and their parents. Youth completed a quantitative sensory testing protocol. Family addresses were used to compute ADI scores. Thermal stimuli for pain threshold and tolerance were delivered to participants' forearms using thermodes. CPM, an index of descending pain inhibition, was determined using a thermode as test stimulus and a hot water bath as conditioning stimulus. RESULTS: As hypothesized, youth with FAP living in lower SES neighborhoods exhibited weaker CPM. Contrary to hypotheses, lower neighborhood SES was associated with neither pain thresholds nor with pain tolerance. CONCLUSIONS: These findings demonstrated the independent contribution of place of residence-an often neglected component of the biopsychosocial model-to efficiency of descending pain inhibition. Understanding the mechanisms that account for such associations between place and pain could guide the development of public health and policy initiatives designed to mitigate chronic pain risk in underserved and economically marginalized communities.

Internet-delivered cognitive behavioral therapy for youth with functional abdominal pain: a randomized clinical trial testing differential efficacy by patient subgroup.

ABSTRACT: Inconsistent results of psychological treatments for pediatric functional abdominal pain (FAP) may be due to heterogeneity of patients' pain-related psychological characteristics. This randomized controlled trial tested whether statistically derived patient subgroups (high pain dysfunctional [HPD], high pain adaptive [HPA], and low pain adaptive [LPA]) moderated response to cognitive behavior therapy (CBT) for adolescents with FAP and their parents (n = 278 dyads; patients were 66% female, mean [SD] age was 14.62 [1.88] years, and parents were 95% female). Randomization to Internet-delivered CBT vs Internet-delivered pain education (EDU) was stratified by patient subgroup. Follow-up assessments of gastrointestinal (GI) symptoms (primary outcome), abdominal pain, and pain interference were at midtreatment, posttreatment, 6 months, and 12 months. Data were analysed using linear mixed effects models. Significant treatment × subgroup × time interaction effects showed that patient subgroup significantly moderated the effect of treatment on GI symptoms (t[853 = -2.93, P = 0.003) and abdominal pain (t(844) = -2.14, P = 0.03) across the treatment period. Among HPD youth, those in CBT had significantly greater GI symptom reduction than those in EDU through posttreatment. By contrast, among HPA and LPA youth, symptom improvement did not differ by treatment condition. Furthermore, among all patients assigned to CBT, HPD youth demonstrated significantly greater reductions in GI symptoms compared with HPA and LPA youth and greater reductions in abdominal pain compared with LPA youth. All subgroups maintained symptom reductions throughout the follow-up period. Results suggest that subgrouping FAP patients may inform treatment allocation and optimize treatment response.

Does Quantitative Sensory Testing Improve Prediction of Chronic Pain Trajectories? A Longitudinal Study of Youth With Functional Abdominal Pain Participating in a Randomized Controlled Trial of Cognitive Behavioral Treatment.

OBJECTIVES: Youth with functional abdominal pain (FAP) experience significant pain-related distress and functional impairment. Although quantitative sensory testing protocols have identified alterations in pain modulatory systems that distinguish youth with FAP from healthy controls, the extent to which evoked pain responses predict subsequent trajectories of pain symptoms and disability over and above established psychosocial risk factors is unclear. METHODS: The present study included 183 adolescents with FAP who were enrolled in a randomized controlled trial comparing an 8-week, internet-delivered program of cognitive behavior therapy (n=90) or pain education (n=93). Participants completed a quantitative sensory testing protocol before the intervention and were followed for 12-month posttreatment. RESULTS: Whereas adolescents with FAP who exhibited stronger baseline conditioned pain modulation (CPM) reported decreases in pain-related interference over follow-up (b=-0.858, SE=0.396, P=0.032), those with weaker CPM exhibited high, relatively stable levels of pain-related interference over time (b=-0.642, SE=0.400, P=0.110). CPM status predicted changes in pain-related interference after controlling for the effects of treatment condition and psychosocial risk factors. Static measures of pain sensitivity (ie, pain threshold, pain tolerance) and temporal summation of second pain were not associated with changes in measures of abdominal pain, gastrointestinal symptom severity, or pain-related interference over follow-up. DISCUSSION: The present findings contribute to a growing literature on the predictive utility of quantitative sensory testing indices and suggest that CPM may complement existing psychosocial risk measures in determining individualized pain-related risk profiles.

The effect of chronic nausea on gastric slow wave spatiotemporal dynamics in children.

BACKGROUND: Chronic nausea in adolescents with functional gastrointestinal disorders is an increasingly reported but poorly understood symptom that negatively affects quality of life. Functional gastrointestinal disorders are known to correlate closely with slow wave rhythm disturbances. The ability to characterize gastric electrophysiologic perturbations in functional nausea patients could provide potential diagnostic and therapeutic tools for nausea patients. METHODS: We used high-resolution electrogastrograms (HR-EGG) to measure gastric slow wave parameters in pediatric chronic nausea patients and healthy subjects both pre- and postprandial. We computed the dominant frequency, percentage power distribution, gastric slow wave propagation direction, and speed from HR-EGG. KEY RESULTS: We observed significant differences in the dominant frequency and power distributed in normal and bradyarrhythmia frequency ranges when comparing patients and healthy subjects. Propagation patterns in healthy subjects were predominantly anterograde, while patients exhibited a variety of abnormalities including retrograde, anterograde, and disrupted patterns. There was a significant difference in the preprandial mean slow wave direction between healthy subjects (222° ± 22°) and patients (103° ± 66°; p Ë‚ 0.01), although the postprandial mean direction between healthy subjects and patients was similar (p = 0.73). No significant difference in slow wave propagation speed was found between patients and healthy subjects in either pre- (p = 0.21) or postprandial periods (p = 0.75). CONCLUSIONS AND INFERENCES: The spatiotemporal characterization of gastric slow wave activity using HR-EGG distinguishes symptomatic chronic nausea patients from healthy subjects. This characterization may in turn inform and direct clinical decision-making and lead to further insight into its pathophysiology.

Comorbid Sleep Disturbance in Adolescents with Functional Abdominal Pain.

OBJECTIVE/BACKGROUND: Sleep disturbances have been commonly reported as comorbid in youth with pain conditions, but prior research specific to functional abdominal pain (FAP) is limited. This study describes individual factors associated with increased risk for sleep disturbance and characterizes the relationship between sleep disturbance and pain-related variables. PARTICIPANTS: Participants included 278 adolescents (age 11 to 17 years, M age = 15 years; 89% Caucasian; 65% female) with FAP. METHODS: Participants reported on sleep disturbances, abdominal pain severity, functional disability, somatic symptoms, and healthcare utilization. RESULTS: Female adolescents reported greater sleep disturbance than male adolescents (t(276) = 5.52, p < .001, Cohen's d = 0.70) and increased age was associated with greater sleep disturbance (r =.20, p =.001). In hierarchical regressions controlling for age, sex, and abdominal pain, greater sleep disturbance was significantly associated with greater functional disability (ß =.32), non-gastrointestinal somatic symptoms (ß =.35), and emergency department visits (ß =.29). CONCLUSIONS: Results suggest that sleep disturbance is common and should be assessed in youth presenting with FAP and may be a potential target for intervention.

Subgroups of Pediatric Patients With Functional Abdominal Pain: Replication, Parental Characteristics, and Health Service Use.

OBJECTIVES: Prior work in a cohort of youth with functional abdominal pain (FAP) identified patient subgroups (High Pain Dysfunctional, High Pain Adaptive, Low Pain Adaptive) that predicted differences in the course of FAP from childhood into young adulthood. We aimed to replicate these subgroups in a new sample of adolescents with FAP using the original classification algorithm and to extend subgroup characteristics to include parental characteristics and health service use. METHODS: Adolescents (n=278; ages 11 to 17 y, 66% females) presenting to a gastroenterology clinic for abdominal pain, and their parents (92% mothers) completed self-report measures; adolescents also completed a 7-day pain diary. RESULTS: The replicated patient subgroups exhibited distress and impairment similar to subgroups in the original sample. Moreover, in novel findings, the High Pain Dysfunctional subgroup differed from other subgroups by the predominance of mother-daughter dyads jointly characterized by high levels of anxiety, depressive symptoms, pain behavior, and pain catastrophizing. The High Pain Dysfunctional subgroup used more health care services than Low Pain Adaptive but did not differ from High Pain Adaptive. DISCUSSION: Findings replicate and extend the original FAP classification and suggest that the subgroups have unique patient and parent features that may reflect distinct illness mechanisms requiring different treatments.

Validation of the Health-Related Felt Stigma and Concealment Questionnaire.

OBJECTIVE: Stigma is associated with many health conditions, including chronic pain. Research on health-related stigma is limited by the lack of validated instruments that distinguish among various stigma-related constructs. We aimed to develop and validate such a measure for pediatric functional abdominal pain (FAP). Felt stigma (FS) was defined as comprising both perceived and internalized stigma. Stigma concealment (SC) was defined as efforts by stigmatized individuals to prevent others from learning of their condition. METHODS: Using a theory-driven approach, we adapted items from existing self-report measures of stigma to construct the health-related FS and Concealment Questionnaire (FSC-Q). Patients with FAP (N = 179, ages 11-17) completed the preliminary FSC-Q and health-related measures hypothesized to be associated with stigma. Cognitive interviewing and exploratory factor analysis (EFA) informed the final version of the measure. RESULTS: EFA identified a 2-factor model comprised of FS and SC. The FS and SC scales exhibited good internal consistency and construct validity. Consistent with study hypotheses, both factors were significantly associated with anxiety, depression, pain catastrophizing, pain threat, physical symptoms, and pain interference/disability. Higher FS was associated with higher mental healthcare utilization. The subset of participants meeting criteria for irritable bowel syndrome (IBS) reported higher FS and SC compared with those without IBS. CONCLUSION: The FSC-Q may help advance research on health-related stigma in FAP and other chronic health conditions by allowing for assessment of distinct stigma-related constructs.

Somatic Symptoms in Pediatric Patients With Chronic Pain: Proposed Clinical Reference Points for the Children's Somatic Symptoms Inventory (Formerly the Children's Somatization Inventory).

Among youth with chronic pain, elevated somatic symptoms across multiple body systems have been associated with greater emotional distress and functional disability and could represent poor adaptation to pain. The Children's Somatic Symptoms Inventory (formerly the Children's Somatization Inventory) is commonly used to assess somatic symptoms in children. However, no studies have evaluated the clinical usefulness of the measure in the assessment of pediatric patients with chronic pain. This study evaluated the factor structure and clinical relevance of the 24-item Children's Somatic Symptoms Inventory (CSSI-24) in youth (n = 1,150) with mixed chronic pain complaints presenting to a tertiary pain clinic. The CSSI-24 total scores were equal or superior to factor scores as indicators of patients' clinical characteristics (functional disability, pain catastrophizing, fear of pain, and anxiety and depressive symptoms) and parental catastrophizing and protective responses. Tertile-derived clinical reference points for the CSSI-24 total score (<18, low; 19-31, moderate; ≥ 32, high) significantly differed on measures of clinical characteristics and parent factors. Controlling for age, sex, pain intensity, and primary pain complaint, the high somatic symptoms group exhibited significantly greater health care use compared with the moderate and low groups. The assessment of somatic symptoms in pediatric patients with chronic pain may provide useful information regarding patients' psychosocial risk and tendency to access health services. Perspective: Clinical reference points based on the CSSI-24 total scores meaningfully differentiated youth with chronic pain on measures of emotional distress, functioning, parent catastrophizing and protective responses, and health care use. Assessing somatic symptoms could provide useful information regarding a pediatric patient's psychosocial risk, tendency to access health services, and need for enhanced care coordination.

Development and Validation of a Nausea Severity Scale for Assessment of Nausea in Children with Abdominal Pain-Related Functional Gastrointestinal Disorders.

The objective of this study was to develop a pediatric measure of chronic nausea severity, the Nausea Severity Scale (NSS), and evaluate its reliability and validity in youth with abdominal pain-related functional gastrointestinal disorders (AP-FGID). Pediatric patients (aged 11⁻17 years-old, n = 236) presenting to an outpatient clinic for evaluation of abdominal pain completed the NSS, Children's Somatization Inventory (CSI), Functional Disability Inventory (FDI), Abdominal Pain Index (API), Patient-Report Outcomes Measurement Information System (PROMIS), Anxiety and Depression Scales and the Pediatric Rome III Questionnaire for FGIDs. The NSS demonstrated good concurrent, discriminant, and construct validity, as well as good internal consistency. One-third (34%) of AP-FGID patients reported experiencing nausea "most" or "every day" in the previous two weeks. The severity of nausea was higher in females than males and correlated significantly with the severity of somatic symptoms, functional disability, anxiety, and depression. The NSS is a valid and reliable measure of nausea in children with AP-FGID.

Is Resolution of Chronic Pain Associated With Changes in Blood Pressure-related Hypoalgesia?

Background: In healthy individuals, elevated resting blood pressure (BP) is associated with reduced pain responsiveness and lower temporal summation. Prior work indicates that this BP-related hypoalgesia is reduced in individuals with chronic pain. Purpose: This study evaluated whether resolution of chronic pain was associated with greater BP-related hypoalgesia compared to nonresolution. Methods: From a prospective sample of adolescents and young adults diagnosed with chronic functional abdominal pain an average of 9 years earlier, 99 individuals in whom the condition had resolved and 51 individuals with ongoing abdominal pain were studied. Resting systolic BP was assessed, followed by evaluation of thermal pain threshold and tolerance, and assessment of temporal summation to thermal pain stimuli. Results: Higher resting systolic BP was significantly associated with higher pain threshold and tolerance, and lower temporal summation only in the group with resolved functional abdominal pain (p < .05). Hierarchical regressions revealed that interactions between BP and resolution of chronic pain were significant only for pain tolerance (p < .05). Analyses by sex indicated that interactions between BP and resolution status were significant for the temporal summation outcome in males but not in females. Conclusions: Results suggest that BP-related hypoalgesic mechanisms may be more effective in individuals in whom chronic pain has resolved compared to those with ongoing chronic pain. Findings hint at sex differences in the extent to which resolution of chronic pain is associated with BP-related hypoalgesia. Whether greater BP-related hypoalgesia is a consequence of, or alternatively a contributor to, resolution of chronic pain warrants further investigation.

Social learning pathways in the relation between parental chronic pain and daily pain severity and functional impairment in adolescents with functional abdominal pain.

Having a parent with chronic pain (CP) may confer greater risk of persistence of CP from childhood into young adulthood. Social learning, such as parental modeling and reinforcement, represents one plausible mechanism for the transmission of risk of CP from parents to offspring. Based on a 7-day pain diary in 154 pediatric patients with functional abdominal CP, we tested a model in which parental CP predicted adolescents' daily average CP severity and functional impairment (distal outcomes) via parental modeling of pain behaviors and parental reinforcement of adolescent's pain behaviors (mediators) and adolescents' cognitive appraisals of pain threat (proximal outcome representing adolescents' encoding of parents' behaviors). Results indicated significant indirect pathways from parental CP status to adolescent average daily pain severity (b = 0.18, SE = 0.08, 95% confidence interval: 0.04-0.31, P = 0.03) and functional impairment (b = 0.08, SE = 0.04, 95% confidence interval: 0.02-0.15, P = 0.03) over the 7-day diary period via adolescents' observations of parent pain behaviors and adolescent pain threat appraisal. The indirect pathway through parental reinforcing responses to adolescents' pain did not reach significance for either adolescent pain severity or functional impairment. Identifying mechanisms of increased risk of pain and functional impairment in children of parents with CP ultimately could lead to targeted interventions aimed at improving functioning and quality of life in families with CP. Parental modeling of pain behaviors represents a potentially promising target for family-based interventions to ameliorate pediatric CP.

Interacting influences of gender and chronic pain status on parasympathetically mediated heart rate variability in adolescents and young adults.

Considerable research links chronic pain to autonomic nervous system (ANS) dysfunction, specifically low heart rate variability (HRV) mediated by reduced parasympathetic activity. However, little is known about factors that influence ANS function in chronic pain. The ANS is the primary pathway for brain-gut communication, making it of particular interest in gastrointestinal disorders, such as irritable bowel syndrome, characterized by functional abdominal pain (FAP). We evaluated the relation of sex, pain severity, and psychological stress to ANS function in adolescents/young adults from a database of pediatric FAP and control participants enrolled 8 years earlier in a prospective study of pain. At follow-up in adolescence/young adulthood (Mean age = 19.46, SD = 3.48), we classified participants as Pain-Remit (n = 130), Pain-Persist (n = 96), and pain-free controls (n = 123). We recorded electrocardiogram data at rest and during laboratory stressors. Results demonstrated significantly lower HRV in Pain-Persist females compared with Pain-Remit females, female controls, and all males regardless of pain category. Spectral analysis of electrocardiogram showed that Pain-Persist females had reduced power in the high frequency domain of cardiac activity, ie, reduced parasympathetic "braking" of sympathetic activity, both at rest and during stress. Pain-Remit females exhibited levels of autonomic imbalance intermediate between those of females with persistent FAP and all other participants. Parasympathetically mediated low HRV in young women with persistent FAP may reflect a peripheral mechanism (eg, gut dysfunction) or a central nervous system mechanism (eg, pain amplification or poor emotion self-regulation) involving prolonged sympathetic activation.