Brain Function and Pain Interference After Pediatric Intensive Interdisciplinary Pain Treatment.

OBJECTIVES: Intensive interdisciplinary pain treatments (IIPTs) are programs that aim to improve functioning in youth with severe chronic pain. Little is known about how the brain changes after IIPT; however, decreased brain responses to emotional stimuli have been identified previously in pediatric chronic pain relative to healthy controls. We examined whether IIPT increased brain responses to emotional stimuli, and whether this change was associated with a reduction in pain interference. PATIENTS AND METHODS: Twenty youths with chronic pain aged 14 to 18 years were scanned using functional magnetic resonance imaging, pre and post-IIPT. During the functional magnetic resonance imaging, patients were presented with emotional stimuli (ie, faces expressing happiness/fear), neutral expressions, and control (ie, scrambled) images. Patients completed a measure of pain interference pre and post-IIPT. Paired t tests were used to examine differences in brain activation in response to emotional versus neutral stimuli, pre to post-IIPT. Data from significant brain clusters were entered into linear mixed models to examine the relationships between brain activation and impairment pre and post-IIPT. RESULTS: Patients demonstrated a decrease in middle frontal gyrus (MFG) activation in response to emotional stimuli (happy + fear) relative to scrambled images, between pre and post-IIPT ( P < 0.05). Lower MFG activation was associated with lower pain interference, pre and post-IIPT ( P < 0.05). CONCLUSION: Contrary to our hypothesis, IIPT was associated with a reduction in MFG activation to emotional stimuli, and this change was associated with reduced pain interference. The MFG is a highly interconnected brain area involved in both pain chronification and antinociception. With further validation of these results, the MFG may represent an important biomarker for evaluating patient treatment response and target for future pain interventions.

Baseline Factors Associated with Pain Intensity, Pain Catastrophizing, and Pain Interference in Intensive Interdisciplinary Pain Treatment for Youth.

Background: More could be known about baseline factors related to desirable Intensive Interdisciplinary Pain Treatment (IIPT) outcomes. This study examined how baseline characteristics (age, gender, child pain catastrophizing (PCS-C), pain interference, pain intensity, anxiety, depression, paediatric health-related quality of life (PedsQLTM), and parent catastrophizing (PCS-P)) were associated with discharge and 3-month follow-up scores of PCS-C, pain intensity, and pain interference. Methods: PCS-C, pain intensity, and pain interference T-scores were acquired in 45 IIPT patients aged 12-18 at intake (baseline), discharge, and 3-month follow-up. Using available and imputed data, linear mixed models were developed to explore associations between PCS-C, pain intensity, and pain interference aggregated scores at discharge and follow-up with baseline demographics and a priori selected baseline measures of pain, depression, anxiety, and PCS-C/P. Results: PCS-C and pain interference scores decreased over time compared to baseline. Pain intensity did not change significantly. Baseline PCS-C, pain interference, anxiety, depression, and PedsQLTM were associated with discharge/follow-up PCS-C (available and imputed data) and pain interference scores (available data). Only baseline pain intensity was significantly associated with itself at discharge/follow-up. Conclusions: Participants who completed the IIPT program presented with reduced PCS-C and pain interference over time. Interventions that target pre-treatment anxiety and depression may optimize IIPT outcomes.

Changes in Brain GABA and Glutamate and Improvements in Physical Functioning Following Intensive Pain Rehabilitation in Youth With Chronic Pain.

Intensive interdisciplinary pain treatments (IIPT) have been developed to treat youth with unmanaged chronic pain and functional disability. Dysregulation of metabolites gamma-aminobutyric acid (GABA) and glutamate are thought to play a role in the chronification of pain due to imbalances in inhibition and excitation in adults. Using magnetic resonance spectroscopy (MRS), we investigated the effect of IIPT on GABA and Glx (glutamate + glutamine) in 2 pain-related brain regions: the left posterior insula (LPI) and the anterior cingulate cortex (ACC). Data were collected in 23 youth (mean age = 16.09 ± 1.40, 19 female) at entry and discharge from a hospital-based outpatient IIPT. GABA and Glx were measured using GABA-edited MEGA-PRESS and analyzed using Gannet. Physical measures including a 6-minute walk test were recorded, and patients completed the PLAYSelf Physical Literacy Questionnaire, PROMIS Pain Interference Questionnaire, and Functional Disability Inventory. LPI GABA (P < .05) significantly decreased, but not ACC GABA (P > .05), following IIPT. There were no significant Glx changes (P > .05). The decrease in LPI GABA was associated with increased distance in the 6-minute walk test (P < .001). IIPT may decrease GABAergic inhibitory tone within the LPI, thereby promoting plasticity and contributing to improvements in physical outcomes with IIPT. PERSPECTIVE: Regional GABA changes are associated with a reduction in pain interference and improvement in physical function in youth following intensive pain rehabilitation. GABA may serve as a possible biomarker for IIPT; and may also further aid in the development of IIPT, and other treatments for chronic pain in youth.

The effect domains, measures, and methods reported in pediatric-specialized multidisciplinary outpatient rehabilitation programs: An integrated review.

OBJECTIVES: Specialized pain rehabilitation is recognized as the treatment of choice for youth with pain-related disability. Appropriate outcomes for program evaluation are critical. This study aimed to summarize the effect domains and methods used to evaluate pediatric-specialized outpatient pain rehabilition programs, map them to the PedIMMPACT statement, and highlight future directions. METHODS: An integrated review framework, incorporating stakeholders, was used. Academic Search Complete, CINAHL, ERIC, MEDLINE, PsycINFO, and Google Scholar were searched for studies published in 1999-2021 featuring the treatment effects of specialized outpatient pain rehabilitation on youth with pain-related disability and their parents. Selected studies were critically appraised using the Quality Assessment Tool for Studies of Diverse Design, organized by study characteristics, and analyzed using constant comparison. RESULTS: From the 1951 potentially relevant titles, 37 studies were selected. Twenty-five effects targeted youth and 24 focused on parents, with a maximum of 15 youth and 11 parent effect domains (median = 5 domains per study). Although most studies measured a combination of effect domains and were inclusive of some recommended in the PedIMMPACT statement, no effect was measured consistently across studies. Youth physical functioning and parent emotional functioning were measured most often. Eighty-five instruments were used to assess youth outcomes and 59 for parents, with self-report questionnaires dominating. DISCUSSION: A lack of standardization exists associated with the domains and methods used to evaluate the effects of pediatric-specialized outpatient pain rehabilitation programs, hindering comparisons. Future program evaluations should be founded on their theory, aim, and anticipated outcomes.

Mistletoes could moderate drought impacts on birds, but are themselves susceptible to drought-induced dieback.

Mistletoes are hemiparasitic plants and keystone species in many ecosystems globally. Given predicted increases in drought frequency and intensity, mistletoes may be crucial for moderating drought impacts on community structure. Dependent on host vascular flows, mistletoes can succumb to stress when water availability falls, making them susceptible to mortality during drought. We counted mistletoe across greater than 350 000 km2 of southeastern Australia and conducted standardized bird surveys between 2016 and 2021, spanning a major drought event in 2018-2019. We aimed to identify predictors of mistletoe abundance and mortality and determine whether mistletoes might moderate drought impacts on woodland birds. Live mistletoe abundance varied with tree species composition, land use and presence of mistletoebirds. Mistletoe mortality was widespread, consistent with high 2018/2019 summer temperatures, low 2019/2020 summer rainfall and the interaction between summer temperatures and rainfall in 2019/2020. The positive association between surviving mistletoes and woodland birds was greatest in the peak drought breeding seasons of 2018/2019 and 2019/2020, particularly for small residents and insectivores. Paradoxically, mistletoes could moderate drought impacts on birds, but are themselves vulnerable to drought-induced mortality. An improved understanding of the drivers and dynamics of mistletoe mortality is needed to address potential cascading trophic impacts associated with mistletoe die-off.

Loss of vocal culture and fitness costs in a critically endangered songbird.

Cultures in humans and other species are maintained through interactions among conspecifics. Declines in population density could be exacerbated by culture loss, thereby linking culture to conservation. We combined historical recordings, citizen science and breeding data to assess the impact of severe population decline on song culture, song complexity and individual fitness in critically endangered regent honeyeaters (Anthochaera phrygia). Song production in the remaining wild males varied dramatically, with 27% singing songs that differed from the regional cultural norm. Twelve per cent of males, occurring in areas of particularly low population density, completely failed to sing any species-specific songs and instead sang other species' songs. Atypical song production was associated with reduced individual fitness, as males singing atypical songs were less likely to pair or nest than males that sang the regional cultural norm. Songs of captive-bred birds differed from those of all wild birds. The complexity of regent honeyeater songs has also declined over recent decades. We therefore provide rare evidence that a severe decline in population density is associated with the loss of vocal culture in a wild animal, with concomitant fitness costs for remaining individuals. The loss of culture may be a precursor to extinction in declining populations that learn selected behaviours from conspecifics, and therefore provides a useful conservation indicator.

Genomic impact of severe population decline in a nomadic songbird.

Uncovering the population genetic histories of non-model organisms is increasingly possible through advances in next generation sequencing and DNA sampling of museum specimens. This new information can inform conservation of threatened species, particularly those for which historical and contemporary population data are unavailable or challenging to obtain. The critically endangered, nomadic regent honeyeater Anthochaera phrygia was abundant and widespread throughout south-eastern Australia prior to a rapid population decline and range contraction since the 1970s. A current estimated population of 250-400 individuals is distributed sparsely across 600,000 km2 from northern Victoria to southern Queensland. Using hybridization RAD (hyRAD) techniques, we obtained a SNP dataset from 64 museum specimens (date 1879-1960), 102 'recent' (1989-2012) and 52 'current' (2015-2016) wild birds sampled throughout the historical and contemporary range. We aimed to estimate population genetic structure, genetic diversity and population size of the regent honeyeater prior to its rapid decline. We then assessed the impact of the decline on recent and current population size, structure and genetic diversity. Museum sampling showed population structure in regent honeyeaters was historically low, which remains the case despite a severe fragmentation of the breeding range. Population decline has led to minimal loss of genetic diversity since the 1980's. Capacity to quantify the overall magnitude of both genetic diversity loss and population decline was limited by the poorer quality of genomic data derived from museum specimens. A rapid population decline, coupled with the regent honeyeater's high mobility, means a detectable genomic impact of this decline has not yet manifested. Extinction may occur in this nomadic species before a detectable genomic impact of small population size is realised. We discuss the implications for genetic management of endangered mobile species and enhancing the value of museum specimens in population genomic studies.

Citizen Science Program Shows Urban Areas Have Lower Occurrence of Frog Species, but Not Accelerated Declines.

Understanding the influence of landscape change on animal populations is critical to inform biodiversity conservation efforts. A particularly important goal is to understand how urban density affects the persistence of animal populations through time, and how these impacts can be mediated by habitat provision; but data on this question are limited for some taxa. Here, we use data from a citizen science monitoring program to investigate the effect of urbanization on patterns of frog species richness and occurrence over 13 years. Sites surrounded by a high proportion of bare ground (a proxy for urbanization) had consistently lower frog occurrence, but we found no evidence that declines were restricted to urban areas. Instead, several frog species showed declines in rural wetlands with low-quality habitat. Our analysis shows that urban wetlands had low but stable species richness; but also that population trajectories are strongly influenced by vegetation provision in both the riparian zone and the wider landscape. Future increases in the extent of urban environments in our study area are likely to negatively impact populations of several frog species. However, existing urban areas are unlikely to lose further frog species in the medium term. We recommend that landscape planning and management focus on the conservation and restoration of rural wetlands to arrest current declines, and the revegetation of urban wetlands to facilitate the re-expansion of urban-sensitive species.