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Malacological surveys were conducted in 2021 in the Kimpese region of Central Kongo Province, west of the Democratic Republic of Congo (DRC). Snail specimens were collected following a standardised protocol, identified using morphological and molecular methods, and tested for schistosome infection using a diagnostic PCR assay. Positive snail samples were sequenced to characterise the infecting schistosome species. Partial mitochondrial cytochrome c oxidase subunit 1 (COX1) gene sequences were used in phylogenetic analyses to explore the evolutionary position of these snail species within the broader African context. At least four intermediate snail hosts were identified: Bulinus truncatus, Bulinus forskalii, Biomphalaria pfeifferi, and a Biomphalaria species belonging to the Nilotic species complex (tentatively named Biomphalaria cf sudanica), of which the species identity needs to be confirmed. A total of 37 out of 1,196 snails (3.1%) tested positive for schistosome infection, with an infection prevalence of 7.4% for B. truncatus with Schistosoma haematobium and 1.5% for Biomphalaria spp. with Schistosoma mansoni. The S. mansoni sequence retrieved from these samples formed a basal clade relative to Zambian isolates, whereas S. haematobium grouped with the most frequently characterised haplotype cluster previously identified across mainland Africa. It is important to note that no animal schistosome species were identified in this study. Both the sequences from the snail hosts and the parasites represent novel contributions from the DRC. Additionally, the findings update the current knowledge of schistosomiasis transmission in the Kimpese region by providing insight into the phylogenetic placement, species diversity, and infection status of local snail populations.
New Zealand and Australian governments rely heavily on voluntary industry initiatives to improve population nutrition, such as voluntary front-of-pack nutrition labelling (Health Star Rating [HSR]), industry-led food advertising standards, and optional food reformulation programmes. Research in both countries has shown that food companies vary considerably in their policies and practices on nutrition(1). We aimed to determine if a tailored nutrition support programme for food companies improved their nutrition policies and practices compared with control companies who were not offered the programme. REFORM was a 24-month, two-country, cluster-randomised controlled trial. 132 major packaged food/drink manufacturers (n=96) and fast-food companies (n=36) were randomly assigned (2:1 ratio) to receive a 12-month tailored support programme or to the control group (no intervention). The intervention group was offered a programme designed and delivered by public health academics comprising regular meetings, tailored company reports, and recommendations and resources to improve product composition (e.g., reducing nutrients of concern through reformulation), nutrition labelling (e.g., adoption of HSR labels), marketing to children (reducing the exposure of children to unhealthy products and brands) and improved nutrition policy and corporate sustainability reporting. The primary outcome was the nutrient profile (measured using HSR) of company food and drink products at 24 months. Secondary outcomes were the nutrient content (energy, sodium, total sugar, and saturated fat) of company products, display of HSR labels on packaged products, company nutrition-related policies and commitments, and engagement with the intervention. Eighty-eight eligible intervention companies (9,235 products at baseline) were invited to participate, of whom 21 accepted and were enrolled in the REFORM programme (delivered between September 2021 and December 2022). Forty-four companies (3,551 products at baseline) were randomised to the control arm. At 24 months, the model-adjusted mean HSR of intervention company products was 2.58 compared to 2.68 for control companies, with no significant difference between groups (mean difference -0.10, 95% CI -0.40 to 0.21, p-value 0.53). A per protocol analysis of intervention companies who enrolled in the programme compared to control companies with no major protocol violation also found no significant difference (2.93 vs 2.64, mean difference 0.29, 95% CI -0.13 to 0.72, p-value 0.18). We found no significant differences between the intervention and control groups in any secondary outcome, except in total sugar (g/100g) where the sugar content of intervention company products was higher than that of control companies (12.32 vs 6.98, mean difference 5.34, 95% CI 1.73 to 8.96, p-value 0.004). The per-protocol analysis for sugar did not show a significant difference (10.47 vs 7.44, mean difference 3.03, 95% CI -0.48 to 6.53, p-value 0.09).In conclusion, a 12-month tailored nutrition support for food companies did not improve the nutrient profile of company products.
Patients with posttraumatic stress disorder (PTSD) exhibit smaller regional brain volumes in commonly reported regions including the amygdala and hippocampus, regions associated with fear and memory processing. In the current study, we have conducted a voxel-based morphometry (VBM) meta-analysis using whole-brain statistical maps with neuroimaging data from the ENIGMA-PGC PTSD working group.
Methods
T1-weighted structural neuroimaging scans from 36 cohorts (PTSD n = 1309; controls n = 2198) were processed using a standardized VBM pipeline (ENIGMA-VBM tool). We meta-analyzed the resulting statistical maps for voxel-wise differences in gray matter (GM) and white matter (WM) volumes between PTSD patients and controls, performed subgroup analyses considering the trauma exposure of the controls, and examined associations between regional brain volumes and clinical variables including PTSD (CAPS-4/5, PCL-5) and depression severity (BDI-II, PHQ-9).
Results
PTSD patients exhibited smaller GM volumes across the frontal and temporal lobes, and cerebellum, with the most significant effect in the left cerebellum (Hedges’ g = 0.22, pcorrected = .001), and smaller cerebellar WM volume (peak Hedges’ g = 0.14, pcorrected = .008). We observed similar regional differences when comparing patients to trauma-exposed controls, suggesting these structural abnormalities may be specific to PTSD. Regression analyses revealed PTSD severity was negatively associated with GM volumes within the cerebellum (pcorrected = .003), while depression severity was negatively associated with GM volumes within the cerebellum and superior frontal gyrus in patients (pcorrected = .001).
Conclusions
PTSD patients exhibited widespread, regional differences in brain volumes where greater regional deficits appeared to reflect more severe symptoms. Our findings add to the growing literature implicating the cerebellum in PTSD psychopathology.
Background: Recent research has demonstrated that DBS sites in Alzheimer’s (AD) and Parkinson’s (PD) influencing cognition are functionally connected to the subiculum. However, the results are mixed, and it is unclear how or if DBS site-subiculum connectivity can be optimized to improve patient cognition. Methods: We studied how subiculum connectivity influenced cognitive outcomes in both PD (subthalamic nucleus) and AD (fornix) DBS patients (total n = 110). We first confirmed DBS site-subiculum connectivity had opposite cognitive effects in each disease. We next investigated patient factors underlying these opposing effects. Lastly, we related our findings back to clinical practice to guide DBS programming in PD and AD. Results: DBS site-subiculum connectivity correlated with cognitive improvement in AD but decline in PD. This was dependent upon hippocampal atrophy; such that higher subiculum connectivity was beneficial when the hippocampus was atrophic but deleterious when it was intact. Finally, we related our findings back to anatomy with cadaveric dissections and present how DBS stimulation can be optimized to improve patient cognition. Conclusions: DBS site-subiculum connectivity influences cognition but depends on patient factors. Thus, to optimize cognition based on patient factors, DBS electrodes can be programmed to stimulate subregions with higher or lower subiculum connectivity.
Background: The complement component C5 inhibitor, ravulizumab, is approved in Canada for the treatment of adults with AQP4-Ab+ NMOSD. Updated efficacy and safety results from the ongoing CHAMPION-NMOSD (NCT04201262) trial are reported. Methods: Participants received IV-administered, weight-based dosing of ravulizumab, with loading on day 1 and maintenance doses on day 15 and every 8 weeks thereafter. Following a primary treatment period (PTP; up to 2.5 years), patients could enter a long-term extension (LTE). Outcome measures included safety, time to first adjudicated on-trial relapse (OTR), risk reduction, and disability scores. Results: 56/41 patients entered/completed the LTE as of June 14, 2024. Median follow-up was 170.3 weeks (186.6 patient-years). No patients experienced an OTR. 94.8% (55/58 patients) had stable or improved Hauser Ambulation Index scores. 89.7% (52/58 patients) had no clinically important worsening in Expanded Disability Status Scale scores. Treatment-emergent adverse events (98.4%) were predominantly mild and unrelated to ravulizumab. Serious adverse events occurred in 25.9% of patients. Two cases of meningococcal infection occurred during the PTP, and none in the LTE. One unrelated death (cardiovascular) occurred during the LTE. Conclusions: Ravulizumab demonstrated long-term clinical benefit in AQP4-Ab+ NMOSD relapse prevention while maintaining or improving disability measures, with no new safety concerns.
Background: Generalized myasthenia gravis (gMG) is a potentially life threatening chronic autoimmune disease that can impair patients’ ability to work effectively and increase reliance on public support benefits. A public economic framework was used to explore how treatment influences patients’ and caregivers’ economic activity, including tax revenues and public support in Canada. Methods: Natural history of gMG was simulated using a multi-state Markov cohort model. Health states were based on MG Activities of Daily Living (MG-ADL) total score in patients with AChR-Ab+ refractory gMG. Treatment, costs, and economic outcomes of patients taking efgartigimod were compared with alternative therapeutic options. Canadian public support benefits were based on official government sources. Results: Improved MG-ADL states predict higher workforce participation, lower rates of disability and less caregiving needs, resulting in higher tax revenues and less public support costs. Compared to alternative therapeutic options, efgartigimod is estimated to yield lifetime fiscal gains of $458,755 that exceed the incremental cost of $291,073, suggesting the Canadian government receives $1.6 for every $1.0 spent on efgartigimod for the treatment of gMG. Conclusions: Compared with alternative options, efgartigimod generated a positive fiscal return for the Canadian governments with additional savings from disease management, public benefits, and averted tax revenue losses.
Background: Efgartigimod, a human immunoglobulin (Ig)G1 antibody Fc fragment, blocks the neonatal Fc receptor, reducing IgGs involved in chronic inflammatory demyelinating polyneuropathy (CIDP). The multi-stage, double-blinded, placebo-controlled ADHERE (NCT04281472) and open-label extension ADHERE+ (NCT04280718) trials (interim analysis cutoff: February 16, 2024) assessed efgartigimod PH20 SC in participants with CIDP. Methods: Participants with active CIDP received open-label, weekly efgartigimod PH20 SC 1000 mg during ≤12-week run-in (stage-A). Responders were randomized (1:1) to efgartigimod or placebo for ≤48 weeks (stage-B). Participants with clinical deterioration in stage-B or who completed ADHERE entered ADHERE+. Week 36 changes from run-in baseline (CFB) in adjusted Inflammatory Neuropathy Cause and Treatment (aINCAT), Inflammatory Rasch-built Overall Disability Scale (I-RODS), and grip strength scores were evaluated. Results: Of 322 stage-A participants, 221 were randomized and treated in stage-B, and 99% entered ADHERE+. Mean CFB (SE) in aINCAT, I-RODS, and grip strength scores were -1.2 (0.15) and 8.8 (1.46) and 17.5 (2.02), respectively, at ADHERE+ Week 36 (N=150). Half the participants with clinical deterioration during ADHERE stage-B restabilized on efgartigimod from ADHERE+ Week 4. Conclusions: Interim results from ADHERE+ indicate long-term effectiveness of efgartigimod PH20 SC in clinical outcomes in participants with CIDP.
Background: Efgartigimod, a human immunoglobulin (Ig)G1 antibody Fc fragment, blocks the neonatal Fc receptor, reducing IgGs involved in chronic inflammatory demyelinating polyneuropathy (CIDP), a rare, progressive, immune-mediated disease that can lead to irreversible disability. The multi-stage, double-blinded, placebo-controlled ADHERE (NCT04281472) trial assessed efgartigimod PH20 SC in participants with CIDP. Methods: Participants with active CIDP received open-label, weekly efgartigimod PH20 SC 1000 mg during ≤12-week run-in (stage-A). Responders were randomized (1:1) to weekly efgartigimod or placebo for ≤48 weeks (stage-B). This posthoc analysis evaluated changes from run-in baseline (study enrollment) to stage-B last assessment and items of the Inflammatory Rasch-built Overall Disability Scale (I-RODS). Results: Of 322 participants who entered stage-A, 221 were randomized and treated in stage-B, and 191/221 had data for run-in baseline and post–stage-B timepoints. Mean (SE) I-RODS change at stage-B last assessment vs run-in baseline was 5.7 (1.88) and -4.9 (1.82) in participants randomized to efgartigimod and placebo, respectively. 37/97 (38.1%) and 24/92 (26.1%) participants randomized to efgartigimod and placebo, respectively, experienced ≥4-point improvements in I-RODS score. Efgartigimod-treated participants improved ≥1 point in I-RODS items of clinical interest. Conclusions: Participants who received efgartigimod in stage-B experienced improvements in I-RODS score from study enrollment to stage-B last assessment.
Background: Neck vessel imaging is often performed in hyperacute stroke to allow neurointerventionalists to estimate access complexity. This study aimed to assess clinician agreement on catheterization strategies based on imaging in these scenarios. Methods: An electronic portfolio of 60 patients with acute ischemic stroke was sent to 53 clinicians. Respondents were asked: (1) the difficulty of catheterization through femoral access with a regular Vertebral catheter, (2) whether to use a Simmons or reverse-curve catheter initially, and (3) whether to consider an alternative access site. Agreement was assessed using Fleiss’ Kappa statistics. Results: Twenty-two respondents (7 neurologists, 15 neuroradiologists) completed the survey. Overall there was slight interrater agreement (κ=0.17, 95% CI: 0.10–0.25). Clinicians with >50 cases annually had better agreement (κ=0.22) for all questions than those with fewer cases (κ=0.07). Agreement did not significantly differ by imaging modality: CTA (κ=0.18) and MRA (κ=0.14). In 40/59 cases (67.80%), at least 25% of clinicians disagreed on whether to use a Simmons or reverse-curve catheter initially. Conclusions: Agreement on catheterization strategies remains fair at best. Our results suggest that visual assessment of pre-procedural vessels imaging is not reliable for the estimation of endovascular access complexity.
Background: Attitudes toward aging influence many health outcomes, yet their relationship with cognition and Alzheimer’s disease (AD) remains unknown. To better understand their impact on cognition and AD risk, we examined whether positive attitudes predict better cognition and diminished risk on AD biomarkers. Methods: A subsample of older adults with a family history of AD (n=54; women=39) from the McGill PREVENT-AD cohort participated in this study. Participants completed the Attitudes to Ageing Questionnaire (AAQ-24), providing three scores: psychosocial loss, psychological growth and physical change. Participants underwent cognitive testing (Rey Auditory Verbal Learning Test, RAVLT; Delis-Kaplan Executive Function System-Color Word Interference Test, D-KEFS-CWIT), and AD blood-based biomarker assessments (p-tau217, Aβ42/40). Regression models tested associations, adjusting for covariates (age, sex, education, depression, APOE4), and were Bonferroni corrected. Results: Positive attitudes were associated with better recall and recognition (RAVLT) and improved word reading, colour naming, switching, and inhibition (D-KEFS-CWIT) (p<0.00077), while negative attitudes showed the opposite pattern. Negative attitudes were correlated with lower Aβ42/40 ratios, while positive attitudes were linked to lower p-tau217 (p<0.0167). Conclusions: These findings demonstrate that positive attitudes predict better cognition and a lower risk profile for AD biomarkers, suggesting that life outlook may be an early disease feature or a risk factor.
Background: Amyotrophic Lateral Sclerosis (ALS) leads to progressive functional decline and reduced survival. Identifying clinical predictors like ALSFRS-R and FVC is essential for prognosis and disease management. Understanding progression profiles based on diagnostic characteristics supports clinical trial design and assessment of treatment response. This study evaluates disease progression and survival predictors in ALS patients from the CNDR. Methods: 1565 ALS patients in the CNDR were analyzed to assess baseline ALSFRS-R, FVC, time from symptom onset to diagnosis, and their association with disease progression and survival. Results: At diagnosis, ALSFRS-R was 44.7 (SD = 5.46), with 72.3% scoring ≥44. Mean FVC was 84.2% (SD = 23.3), with 78.3% of patients having FVC ≥65%. ALSFRS-R declined at 1.06 points/month (SD = 1.33), with faster progression in patients diagnosed within 24 months (1.61 points/month). Patients with ALSFRS-R ≥44 had a median survival of 41.8 months, compared to 30.9 months for those <44 (p < 0.001). Similarly, FVC ≥65% was associated with longer survival (35.4 vs. 29.5 months, p = 0.002). Conclusions: ALSFRS-R and FVC at diagnosis predict survival and inform clinical decision-making. These findings highlight the importance of early diagnosis and targeted interventions to slow disease progression and improve patient outcomes.
Background: Plasma pTau217 is a robust biomarker for the diagnosis of Alzheimer’s disease (AD). However, most pTau217 assays are not widely available for clinical testing. We assessed the performance of two commercially available plasma pTau217 immunoassays in a clinical diagnostic laboratory for AD diagnosis. Methods: 219 plasma samples from healthy controls with negative amyloid PET, 115 plasma samples from pathology-confirmed and 263 samples with confirmed amyloid PET were selected. Plasma pTau217 levels were measured using the ALZpath pTau217 assay on the Quanterix HD-X Simoa platform and the Lumipulse pTau217 assay on the Lumipulse G1200 platform at and BC Neuroimmunology Lab and Neurocode USA. Results: For the ALZpath assay, the coefficients were 10.4%, 10.4%, and 9.9%, and for the Fujirebio assay, were 12.1%, 12.2%, and 5.3%, respectively. Sample stability and interference were similar between the two assays, although moderate heterophilic antibody interference and reduced frozen sample stability at -20˚C were observed for the Fujirebio assay. Both assays demonstrated similar clinical performance and differentiated individuals with AD (ALZpath AUC = 0.94; Fujirebio AUC = 0.90). Conclusions: The performance of the two pTau 217 assays was comparable. The clinical separation between the healthy controls and those with Amyloid pathology was nearly complete for both assays.
High density should drive greater parasite exposure. However, evidence linking density with infection generally uses density proxies or measures of population size, rather than measures of individuals per space within a continuous population. We used a long-term study of wild sheep to link within-population spatiotemporal variation in host density with individual parasite counts. Although four parasites exhibited strong positive relationships with local density, these relationships were mostly restricted to juveniles and faded in adults. Furthermore, one ectoparasite showed strong negative relationships across all age classes. In contrast, population size – a measure of global density – had limited explanatory power, and its effects did not remove those of spatial density, but were distinct. These results indicate that local and global density can exhibit diverse and contrasting effects on infection within populations. Spatial measures of within-population local density may provide substantial additional insight to temporal metrics based on population size, and investigating them more widely could be revealing.
Multicenter clinical trials are essential for evaluating interventions but often face significant challenges in study design, site coordination, participant recruitment, and regulatory compliance. To address these issues, the National Institutes of Health’s National Center for Advancing Translational Sciences established the Trial Innovation Network (TIN). The TIN offers a scientific consultation process, providing access to clinical trial and disease experts who provide input and recommendations throughout the trial’s duration, at no cost to investigators. This approach aims to improve trial design, accelerate implementation, foster interdisciplinary teamwork, and spur innovations that enhance multicenter trial quality and efficiency. The TIN leverages resources of the Clinical and Translational Science Awards (CTSA) program, complementing local capabilities at the investigator’s institution. The Initial Consultation process focuses on the study’s scientific premise, design, site development, recruitment and retention strategies, funding feasibility, and other support areas. As of 6/1/2024, the TIN has provided 431 Initial Consultations to increase efficiency and accelerate trial implementation by delivering customized support and tailored recommendations. Across a range of clinical trials, the TIN has developed standardized, streamlined, and adaptable processes. We describe these processes, provide operational metrics, and include a set of lessons learned for consideration by other trial support and innovation networks.
Intensive longitudinal data (ILD) collected in mobile health (mHealth) studies contain rich information on the dynamics of multiple outcomes measured frequently over time. Motivated by an mHealth study in which participants self-report the intensity of many emotions multiple times per day, we describe a dynamic factor model that summarizes ILD as a low-dimensional, interpretable latent process. This model consists of (i) a measurement submodel—a factor model—that summarizes the multivariate longitudinal outcome as lower-dimensional latent variables and (ii) a structural submodel—an Ornstein–Uhlenbeck (OU) stochastic process—that captures the dynamics of the multivariate latent process in continuous time. We derive a closed-form likelihood for the marginal distribution of the outcome and the computationally-simpler sparse precision matrix for the OU process. We propose a block coordinate descent algorithm for estimation and use simulation studies to show that it has good statistical properties with ILD. Then, we use our method to analyze data from the mHealth study. We summarize the dynamics of 18 emotions using models with one, two, and three time-varying latent factors, which correspond to different behavioral science theories of emotions. We demonstrate how results can be interpreted to help improve behavioral science theories of momentary emotions, latent psychological states, and their dynamics.
Recent changes to US research funding are having far-reaching consequences that imperil the integrity of science and the provision of care to vulnerable populations. Resisting these changes, the BJPsych Portfolio reaffirms its commitment to publishing mental science and advancing psychiatric knowledge that improves the mental health of one and all.
Cortical excitability has been proposed as a novel neurophysiological marker of neurodegeneration in Alzheimer’s dementia (AD). However, the link between cortical excitability and structural changes in AD is not well understood.
Objective:
To assess the relationship between cortical excitability and motor cortex thickness in AD.
Methods:
In 62 participants with AD (38 females, mean ± SD age = 74.6 ± 8.0) and 47 healthy control (HC) individuals (26 females, mean ± SD age = 71.0 ± 7.9), transcranial magnetic stimulation resting motor threshold (rMT) was determined, and T1-weighted MRI scans were obtained. Skull-to-cortex distance was obtained manually for each participant using MNI coordinates of the motor cortex (x = −40, y = −20, z = 52).
Results:
The mean skull-to-cortex distances did not differ significantly between participants with AD (22.9 ± 4.3 mm) and HC (21.7 ± 4.3 mm). Participants with AD had lower motor cortex thickness than healthy individuals (t(92) = −4.4, p = <0.001) and lower rMT (i.e., higher excitability) than HC (t(107) = −2.0, p = 0.045). In the combined sample, rMT was correlated positively with motor cortex thickness (r = 0.2, df = 92, p = 0.036); however, this association did not remain significant after controlling for age, sex and diagnosis.
Conclusions:
Patients with AD have decreased cortical thickness in the motor cortex and higher motor cortex excitability. This suggests that cortical excitability may be a marker of neurodegeneration in AD.
The Australian SKA Pathfinder (ASKAP) offers powerful new capabilities for studying the polarised and magnetised Universe at radio wavelengths. In this paper, we introduce the Polarisation Sky Survey of the Universe’s Magnetism (POSSUM), a groundbreaking survey with three primary objectives: (1) to create a comprehensive Faraday rotation measure (RM) grid of up to one million compact extragalactic sources across the southern $\sim50$% of the sky (20,630 deg$^2$); (2) to map the intrinsic polarisation and RM properties of a wide range of discrete extragalactic and Galactic objects over the same area; and (3) to contribute interferometric data with excellent surface brightness sensitivity, which can be combined with single-dish data to study the diffuse Galactic interstellar medium. Observations for the full POSSUM survey commenced in May 2023 and are expected to conclude by mid-2028. POSSUM will achieve an RM grid density of around 30–50 RMs per square degree with a median measurement uncertainty of $\sim$1 rad m$^{-2}$. The survey operates primarily over a frequency range of 800–1088 MHz, with an angular resolution of 20” and a typical RMS sensitivity in Stokes Q or U of 18 $\mu$Jy beam$^{-1}$. Additionally, the survey will be supplemented by similar observations covering 1296–1440 MHz over 38% of the sky. POSSUM will enable the discovery and detailed investigation of magnetised phenomena in a wide range of cosmic environments, including the intergalactic medium and cosmic web, galaxy clusters and groups, active galactic nuclei and radio galaxies, the Magellanic System and other nearby galaxies, galaxy halos and the circumgalactic medium, and the magnetic structure of the Milky Way across a very wide range of scales, as well as the interplay between these components. This paper reviews the current science case developed by the POSSUM Collaboration and provides an overview of POSSUM’s observations, data processing, outputs, and its complementarity with other radio and multi-wavelength surveys, including future work with the SKA.
Increased temporal variability in the gut microbiome is associated with intestinal conditions such as ulcerative colitis and Crohn’s disease, leading to the recently established concept of microbial volatility (1). Increased physiological stress has been shown to increase microbial volatility indicating that microbial volatility is susceptible to external interventions(1). Dietary fibre positively affects the gut microbiome, but it is unclear if it impacts microbial volatility. The gut microbiota influences hypertension, and high-fibre intake reduces blood pressure (BP)(2). However, not all individuals exhibit a response to these fibre-based dietary changes, and the reasons for this variability remain unclear. Similarly, it is unknown whether the degree of stability of the gut microbiota consortium could be a determining factor in individual responsiveness to dietary interventions. Here, we aimed to identify: i) whether gut microbiome volatility differs when dietary fibre vs placebo interventions, and ii) whether microbiome volatility discriminates between BP responders and non-responders to a high fibre intervention. Twenty treatment-naive participants with hypertension received either placebo or 40g per day of prebiotic acetylated and butyrylated high amylose maize starch (HAMSAB) supplementation for 3 weeks in a phase II randomised cross-over double-blind placebo-controlled trial(3). Blood pressure was monitored at baseline and each endpoint by 24-hour ambulatory BP monitoring, with those experiencing a reduction between timepoints of ≥ 2 mmHg classified as responders. Baseline stool samples were collected, and the V4 region of the 16S gene was sequenced. Taxonomy was assigned by reference to the SILVA database. Microbial volatility between timepoints (e.g., pre- and post-intervention) was calculated as the Euclidian distance of centred log-ratio transformed genera counts (Aitchison distance). No difference was observed in microbial volatility between individuals when they received the dietary fibre intervention or the placebo (21.5 ± 5.5 vs 20.5 ± 7.7, p = 0.51). There was no significant difference between microbial volatility on the dietary intervention between responders and non-responders (21.8 ± 4.9 vs 20.9 ± 7.2, p = 0.84). There was no association between the change in BP during intervention and microbial volatility during intervention (r2 = −0.09, p = 0.72). These data suggest that temporal volatility of the gut microbiota does not change with fibre intake or contribute to the BP response to dietary fibre intervention trials in people with hypertension.
Posttraumatic stress disorder (PTSD) has been associated with advanced epigenetic age cross-sectionally, but the association between these variables over time is unclear. This study conducted meta-analyses to test whether new-onset PTSD diagnosis and changes in PTSD symptom severity over time were associated with changes in two metrics of epigenetic aging over two time points.
Methods
We conducted meta-analyses of the association between change in PTSD diagnosis and symptom severity and change in epigenetic age acceleration/deceleration (age-adjusted DNA methylation age residuals as per the Horvath and GrimAge metrics) using data from 7 military and civilian cohorts participating in the Psychiatric Genomics Consortium PTSD Epigenetics Workgroup (total N = 1,367).
Results
Meta-analysis revealed that the interaction between Time 1 (T1) Horvath age residuals and new-onset PTSD over time was significantly associated with Horvath age residuals at T2 (meta β = 0.16, meta p = 0.02, p-adj = 0.03). The interaction between T1 Horvath age residuals and changes in PTSD symptom severity over time was significantly related to Horvath age residuals at T2 (meta β = 0.24, meta p = 0.05). No associations were observed for GrimAge residuals.
Conclusions
Results indicated that individuals who developed new-onset PTSD or showed increased PTSD symptom severity over time evidenced greater epigenetic age acceleration at follow-up than would be expected based on baseline age acceleration. This suggests that PTSD may accelerate biological aging over time and highlights the need for intervention studies to determine if PTSD treatment has a beneficial effect on the aging methylome.