Posttraumatic stress disorder and chronic musculoskeletal pain : how are they related?

Indiana University-Purdue University Indianapolis (IUPUI)Symptoms of post-traumatic stress disorder (PTSD) are a common comorbidity in veterans seeking treatment of chronic musculoskeletal pain (CMP). However, little is known regarding the mutual influence of PTSD and CMP in this population. Using cross-sectional and longitudinal data from a randomized clinical trial evaluating a stepped care intervention for CMP in Iraq/Afghanistan veterans (ESCAPE), this dissertation examined the relationships between PTSD and CMP along with other factors including depression, anxiety, catastrophizing and health-related quality of life. The Classification and Regression Tree (CART) analysis was conducted to identify key factors associated with baseline PTSD besides CMP severity. A series of statistical analyses including logistical regression analysis, mixed model repeated measure analysis, confirmatory factor analysis and cross-lagged panel analysis via structural equation modeling were conducted to test five competing models of PTSD symptom clusters, and to examine the mutual influences of PTSD symptom clusters and CMP outcomes. Results showed baseline pain intensity and pain disability predicted PTSD at 9 months. And baseline PTSD predicted improvement of pain disability at 9 months. Moreover, direct relationships were found between PTSD and the disability component of CMP, and indirect relationships were found between PTSD, CMP and CMP components (intensity and disability) mediated by depression, anxiety and pain catastrophizing. Finally, the coexistence of PTSD and more severe pain was associated with worse SF-36 Physical Component Summary (PCS) and Mental Component Summary (MCS) scores. Together these findings provided empirical support for the mutual maintenance theory

Impact of anxiety symptoms on outcomes of depression: an observational study in Asian patients

OBJECTIVE: To investigate the impact of anxiety symptoms on depression outcomes in Asian patients with major depressive disorder (MDD) (n=714). METHODS: The 17-item Hamilton Depression Scale (HAMD-17), overall severity, somatic symptoms, and quality of life (QOL) (EuroQOL Questionnaire-5 Dimensions [EQ-5D]) were assessed at baseline and 3 months. Anxiety was measured using items 10 and 11 from the HAMD-17. Linear, tobit, and logistic multiple regression models analyzed the impact of anxiety symptoms on outcomes. Baseline anxiety was related to age and the presence of pain symptoms at baseline. RESULTS: Regression models showed that a higher level of anxiety was associated with a lower frequency of remission and lower QOL at 3 months. Patients with lower baseline anxiety symptoms had higher remission rates (odds ratio for each point of anxiety symptoms, 0.829 [95% confidence interval [CI]: 0.723-0.951]). Patients with higher levels of baseline anxiety had a lower QOL at 3 months (a decrease in EQ-5D tariff score for each point of anxiety symptoms, 0.023 [95% CI: 0.045-0.001]). CONCLUSION: In conclusion, the presence of anxiety symptoms negatively impacts the outcomes of depression

MEMS Biomimetic Acoustic Pressure Gradient Sensitive Structure for Sound Source Localization

The parasitoid fly Ormia ochracea shows an astonishing localization ability with its tiny hearing organ. A novel MEMS biomimetic acoustic pressure gradient sensitive structure was designed and fabricated by mimicking the mechanically coupled tympana of the fly. Firstly, the analytic representation formulas of the resultant force and resultant moment of the incoming plane wave acting on the structure were derived. After that, structure modal analysis was performed and the results show that the structure has out-of-phase and in-phase vibration modes, and the corresponding eigenfrequency is decided by the stiffness of vertical torsional beam and horizontal beam respectively. Acoustic-structural coupled analysis was performed and the results show that phase difference and amplitude difference between the responses of the two square diaphragms of the sensitive structure are effectively enlarged through mechanical coupling beam. The phase difference and amplitude difference increase with increasing incident angle and can be used to distinguish the direction of sound arrival. At last, the fabrication process and results of the device is also presented

Delayed-Release Dimethyl Fumarate Safety and Efficacy in Pediatric Patients With Relapsing-Remitting Multiple Sclerosis

Background: Pediatric multiple sclerosis (MS) is rare: only 1.5-5% of MS cases are diagnosed before 18 years of age, and data on disease-modifying therapies (DMTs) for pediatric MS are limited. The CONNECTED study assessed the long-term safety and efficacy of treatment with delayed-release dimethyl fumarate (DMF), an oral MS DMT, in pediatric patients with MS. Methods: CONNECTED is the 96-week extension to FOCUS, a 24-week phase 2 study of patients aged 13-17 years;participants received DMF 240 mg twice daily. Endpoints included (primary) incidence of adverse events (AEs), serious AEs, and DMF discontinuations due to an AE, and (secondary) T2 hyperintense lesion incidence by magnetic resonance imaging and annualized relapse rate (ARR). Results: Twenty participants [median (range) age, 17 (14-18) years;65% female] who completed FOCUS enrolled into CONNECTED;17 (85%) completed CONNECTED. Eighteen participants (90%) experienced AEs: the most frequent was flushing (25%). None experienced infections or fever related to low lymphocyte counts. Three participants experienced four serious AEs;none led to DMF discontinuation. Twelve of 17 participants (71%) had no new/newly enlarged T2 lesions from weeks 16-24, two (12%) had one, and one each (6%) had two, three, or five or more lesions [median (range), 0 (0-6)]. Over the full 120-week treatment period, ARR was 0.2, an 84.5% relative reduction (n = 20;95% confidence interval: 66.8-92.8;p < 0.0001) vs. the year before DMF initiation. Conclusions: The long-term safety and efficacy observed in CONNECTED was consistent with adults, suggesting pediatric and adolescent patients with MS might benefit from DMF treatment

Shape of the concentration–response association between fine particulate matter pollution and human mortality in Beijing, China, and its implications for health impact assessment, The

Includes bibliographical references (pages 107009-12-107009-14).Publisher version: https://doi.org/10.1289/EHP4464.Background: Studies found approximately linear short-term associations between particulate matter (PM) and mortality in Western communities. However, in China, where the urban PM levels are typically considerably higher than in Western communities, some studies suggest nonlinearity in this association. Health impact assessments (HIA) of PM in China have generally not incorporated nonlinearity in the concentration–response (C-R) association, which could result in large discrepancies in estimates of excess deaths if the true association is nonlinear. Objectives: We investigated nonlinearity in the C-R associations between with PM with aerodynamic diameter ≤2.5μm (PM2.5) and mortality in Beijing, China, and the sensitivity of HIA to linearity assumptions. Methods: We modeled the C-R association between PM2.5 and cause-specific mortality in Beijing, China (2009–2012), using generalized linear models (GLM). PM2.5 was included through either linear, piecewise-linear, or spline functions to investigate evidence of nonlinearity. To determine the sensitivity of HIA to linearity assumptions, we estimated PM2.5-attributable deaths using both linear- and nonlinear-based C-R associations between PM2.5 and mortality. Results: We found some evidence that, for nonaccidental and circulatory mortality, the shape of the C-R association was relatively flat at lower concentrations of PM2.5, but then had a positive slope at higher concentrations, indicating nonlinearity. Conversely, the shape for respiratory mortality was positive and linear at lower concentrations of PM2.5, but then leveled off at the higher concentrations. Estimates of excess deaths attributable to short-term PM2.5 exposure were, in some cases, very sensitive to the linearity assumption in the association, but in other cases robust to this assumption. Conclusions: Our results demonstrate some evidence of nonlinearity in PM2.5–mortality associations and that an assumption of linearity in this association can influence HIAs, highlighting the importance of understanding potential nonlinearity in the PM2.5–mortality association at the high concentrations of PM2.5 in developing megacities like Beijing. https://doi.org/10.1289/EHP446