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1.
Chronic Obstr Pulm Dis ; 11(2): 187-195, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38237091

ABSTRACT

Background: The neutrophil-to-lymphocyte ratio (NLR) is an inexpensive biomarker that potentially predicts acute exacerbations of chronic obstructive pulmonary disease (AECOPDs). We evaluated the association of baseline NLR and respiratory hospitalization risk within one year among chronic obstructive pulmonary disease (COPD) patients in Uganda, a low- and middle-income country. Methods: A total of 312 COPD patients were followed for one year. Clinical characteristics and exacerbation rates were collected. Poisson regression with robust variance estimators was used to measure the association between NLR and hospital admissions due to COPD exacerbations. Receiver-operator characteristic (ROC) curves and the area under the curve were used to assess the ability of NLR to predict AECOPDs. Results: The median (Q 1, Q 3) age was 64 years (53, 71). Females comprised 50.96% (n=159) of the cohort, and 71.2% (n=222) of participants had moderate or severe COPD. A total of 9.9% (n=31) of participants experienced a COPD exacerbation during the period of follow-up. At baseline, the median (Q 1, Q 3) NLR ratio among participants who experienced an exacerbation was 1.46 (0.92, 2.33) compared to 1.03 (0.72,1.42) among those who did not experience one during the follow-up period (p=0.002). Using Youden and Liu's methods, the optimal NLR cutoff for predicting COPD exacerbation was 1.17. This cutoff resulted in a ROC curve area of 0.64 (95% confidence interval: 0.56, 0.73). Conclusion: The NLR could be used as a risk predictor, in low- and middle-income countries, for hospital admissions due to COPD exacerbations. A cutoff of 1.17 was an independent predictor of hospitalization due to acute exacerbations of COPD within one year.

2.
J Subst Use Addict Treat ; 160: 209298, 2024 May.
Article in English | MEDLINE | ID: mdl-38262559

ABSTRACT

INTRODUCTION: Hospitalizations due to severe injection-related infections (SIRIs) and patient-directed discharge (PDD) in people who inject drugs (PWID) are increasing, but research on readmission outcomes at PDD is limited. In this retrospective, matched cohort study we evaluated predictors of 30-day readmission by discharge status among PWID. METHODS: Among patients diagnosed with SIRIs at a tertiary hospital, Fisher's exact tests assessed differences in readmission rates by discharge status. Medications for opioid use disorder (MOUD) at discharge was defined as either having a buprenorphine dose dispensed within 24 h of discharge and buprenorphine being included in the discharge summary as a prescription, or a methadone dose dispensed inpatient within 24 h of discharge. Logistic regression analyses evaluated predictors of readmission outcomes. RESULTS: Among 148 PWID with SIRI diagnosis, 30-day readmission rate following PDD was higher than standard discharge (25.7 % vs. 9.5 %, p = 0.016) and MOUD decreased odds of 30-day readmission (OR = 0.32, 95 % CI: 0.12,0.83, p = 0.012). >7 missed days of antibiotic treatment increased odds of 30-day readmission (OR 4.65, 95 % CI: 1.14, 31.72, p = 0.030) within PDD patients. CONCLUSIONS: PDD carries higher 30-day readmission rate compared to standard discharge. Strategies to reduce PDD rates and increase MOUD initiation may improve readmission outcomes.


Subject(s)
Buprenorphine , Methadone , Opioid-Related Disorders , Patient Readmission , Substance Abuse, Intravenous , Humans , Patient Readmission/statistics & numerical data , Male , Female , Opioid-Related Disorders/epidemiology , Retrospective Studies , Adult , Middle Aged , Substance Abuse, Intravenous/complications , Substance Abuse, Intravenous/epidemiology , Methadone/therapeutic use , Methadone/administration & dosage , Buprenorphine/therapeutic use , Buprenorphine/administration & dosage , Patient Discharge/statistics & numerical data , Opiate Substitution Treatment/adverse effects , Cohort Studies
3.
Chronic Obstr Pulm Dis ; 11(1): 114-120, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-37828644

ABSTRACT

The advancement of artificial intelligence (AI) capabilities has paved the way for a new frontier in medicine, which has the capability to reduce the burden of COPD globally. AI may reduce health care-associated expenses while potentially increasing diagnostic specificity, improving access to early COPD diagnosis, and monitoring COPD progression and subsequent disease management. We evaluated how AI can be integrated into COPD diagnosing globally and leveraged in resource-constrained settings.AI has been explored in diagnosing and phenotyping COPD through auscultation, pulmonary function testing, and imaging. Clinician collaboration with AI has increased the performance of COPD diagnosing and highlights the important role of clinical decision-making in AI integration. Likewise, AI analysis of computer tomography (CT) imaging in large population-based cohorts has increased diagnostic ability, severity classification, and prediction of outcomes related to COPD. Moreover, a multimodality approach with CT imaging, demographic data, and spirometry has been shown to improve machine learning predictions of the progression to COPD compared to each modality alone. Prior research has primarily been conducted in high-income country settings, which may lack generalization to a global population. AI is a World Health Organization priority with the potential to reduce health care barriers in low- and middle-income countries. We recommend a collaboration between clinicians and an AI-supported multimodal approach to COPD diagnosis as a step towards achieving this goal. We believe the interplay of CT imaging, spirometry, biomarkers, and sputum analysis may provide unique insights across settings that could provide a basis for clinical decision-making that includes early intervention for those diagnosed with COPD.

4.
Article in English | MEDLINE | ID: mdl-37510595

ABSTRACT

Low educational attainment and high cancer incidence and mortality rates have long been a challenge in Appalachian Kentucky. Prior studies have reported disparities in cancer incidence and mortality between Appalachian and non-Appalachian populations, but the influence of education on this disparity has not been extensively studied. Herein, all cancers and two cancer sites with available screenings (colorectal and lung) were joined with education indicators (educational attainment and literacy) and one geographic indicator across all 120 Kentucky counties. This dataset was used to build choropleth maps and perform simple linear and spatial regression to assess statistical significance and to measure the strength of the linear relationship between county-level education and cancer-related outcomes in Appalachian and non-Appalachian Kentucky. Among all cancer sites, age-adjusted cancer incidence and mortality was higher in Appalachian versus non-Appalachian Kentucky. The percentage of the population not completing high school was positively correlated with increased colorectal and lung cancer incidence and mortality in Appalachia. Similarly, counties with a higher percentage of the population lacking basic literacy had the strongest correlation with colorectal and lung cancer incidence and mortality, which were concentrated in Appalachian Kentucky. Our findings suggest a need for implementing interventions that increase educational attainment and enhance basic literacy as a means of improving cancer outcomes in Appalachia.


Subject(s)
Colorectal Neoplasms , Lung Neoplasms , Humans , Kentucky/epidemiology , Literacy , Appalachian Region/epidemiology , Educational Status , Lung Neoplasms/epidemiology , Spatial Analysis , Colorectal Neoplasms/epidemiology , Colorectal Neoplasms/prevention & control , Lung
5.
J Immigr Minor Health ; 25(3): 728-732, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36472714

ABSTRACT

COVID-19 has heavily impacted the refugee population in the United States due to exposure risks, living and working conditions, and healthcare access, but little is known about outcomes. We reviewed emergency department visits to a Kentucky hospital among 2163 patients from March-December 2020, studying incidence of COVID-19 diagnosis for patients with a primary refugee-associated language compared to English speakers, and outcomes after diagnosis including hospitalization, length of stay, and in-hospital mortality. Patients in the population of interest had higher odds of COVID-19 diagnosis in the hospital (OR = 12.31, 95% CI 7.80-19.40), but, among those with COVID-19, lower odds of hospital admission (OR = 0.58, 95% CI 0.37-0.90) and shorter median length of stay (4.1 vs. 10.5 days) compared to English speakers. The study corroborates reports of comparatively higher COVID-19 incidence in patients speaking a primary refugee-associated language, but implies milder illness severity, possibly reflecting this population's baseline health.


Subject(s)
COVID-19 , Refugees , Humans , COVID-19 Testing , Emergency Service, Hospital , Kentucky/epidemiology , Language , Retrospective Studies , United States
6.
ERJ Open Res ; 8(4)2022 Oct.
Article in English | MEDLINE | ID: mdl-36578631

ABSTRACT

Background: American Thoracic Society/European Respiratory Society guidelines recommend context-specific exposure assessments to diagnose interstitial lung disease (ILD). In sub-Saharan Africa, ILD diagnoses are rare, and locally validated ILD exposure questionnaires are not used. Methods: A physician-administered ILD exposure questionnaire was developed using a four-step mixed-methods modified Delphi approach. First, ILD questionnaires from high-income countries and data from Pneumotox were reviewed, compiled and face-validated. Second, a local pilot group of ILD experts ranked item relevance using a Likert scale and suggested additions. Third, the questionnaire format and pilot rankings were addressed in a focus group discussion that was analysed using grounded theory. Finally, following focus group discussion modifications, the resulting items (with three duplicate item groups for evaluation of internal consistency) were ranked for importance by members of the Pan-African Thoracic Society (PATS). Results: Face validation resulted in 82 items in four categories: "Smoking and Drugs", "Environmental Exposures", "Occupations" and "Medications". Pilot group (n=10) ranking revealed 27 outliers and 30 novel suggestions. Focus group (n=12) discussion resulted in 10 item deletions, 14 additions and 22 re-wordings; themes included desire for extensive questionnaires and stigma sensitivity. Final validation involved 58 PATS members (mean±sd age 46±10.6  years, 76% male, from 17 countries) ranking 84 items derived from previous steps and three duplicate question groups. The questionnaire was internally consistent (Cronbach's α >0.80) and ultimately included 73 items. Conclusion: This mixed-methods study included experts from 17 countries in sub-Saharan Africa and successfully developed a 73-item ILD exposure questionnaire for sub-Saharan Africa. African pulmonary experts valued region-specific additions and ranked several items from existing ILD questionnaires as unimportant.

7.
Front Immunol ; 13: 1085551, 2022.
Article in English | MEDLINE | ID: mdl-36741369

ABSTRACT

Chronic Obstructive Pulmonary Disease (COPD) has significantly contributed to global mortality, with three million deaths reported annually. This impact is expected to increase over the next 40 years, with approximately 5 million people predicted to succumb to COPD-related deaths annually. Immune mechanisms driving disease progression have not been fully elucidated. Airway microbiota have been implicated. However, it is still unclear how changes in the airway microbiome drive persistent immune activation and consequent lung damage. Mechanisms mediating microbiome-immune crosstalk in the airways remain unclear. In this review, we examine how dysbiosis mediates airway inflammation in COPD. We give a detailed account of how airway commensal bacteria interact with the mucosal innate and adaptive immune system to regulate immune responses in healthy or diseased airways. Immune-phenotyping airway microbiota could advance COPD immunotherapeutics and identify key open questions that future research must address to further such translation.


Subject(s)
Microbiota , Pulmonary Disease, Chronic Obstructive , Humans , Lung , Inflammation , Disease Progression
8.
PLOS Glob Public Health ; 2(12): e0001309, 2022.
Article in English | MEDLINE | ID: mdl-36962898

ABSTRACT

INTRODUCTION: Despite the rising burden of chronic respiratory disease globally, and although many respiratory medications are included in the World Health Organization Essential Medications List (WHO-EML), there is limited information concerning the availability and affordability of treatment drugs for respiratory conditions in low- and middle-income countries (LMICs). METHODS: All public and private pharmacies in catchment areas of the Global Excellence in COPD outcomes (GECo) study sites in Bhaktapur, Nepal, Lima, Peru, and Nakaseke, Uganda, were approached in 2017-2019 to assess pricing and availability of medications for the management of asthma and COPD. RESULTS: We surveyed all 63 pharmacies in respective study areas in Nepal (95.2% private), 104 pharmacies in Peru (94.2% private) and 53 pharmacies in Uganda (98.1% private). The availability of any medication for respiratory disease was higher in private (93.3%) compared to public (73.3%) pharmacies. Salbutamol (WHO-EML) monotherapy in any formulation was the most commonly available respiratory medication among the three sites (93.7% Nepal, 86.5% Peru and 79.2% Uganda) while beclomethasone (WHO-EML) was only available in Peru (33.7%) and Nepal (22%). LABA-LAMA combination therapy was only available in Nepal (14.3% of pharmacies surveyed). The monthly treatment cost of respiratory medications was lowest in Nepal according to several cost metrics: the overall monthly cost, the median price ratio comparing medication costs to international reference prices at time of survey in dollars, and in terms of days' wages of the lowest-paid government worker. For the treatment of intermittent asthma, defined as 100 mcg Salbutamol/Albuterol inhaler, days' wages ranged from 0.47 days in Nepal and Peru to 3.33 days in Uganda. CONCLUSION: The availability and pricing of respiratory medications varied across LMIC settings, with medications for acute care of respiratory diseases being more widely available than those for long-term management.

9.
Exp Neurol ; 341: 113718, 2021 07.
Article in English | MEDLINE | ID: mdl-33844986

ABSTRACT

Studies in rodents indicate that pairing vagus nerve stimulation (VNS) with extinction training enhances fear extinction. However, the role of stimulation parameters on the effects of VNS remains largely unknown. Identifying the optimal stimulation intensity is a critical step in clinical translation of neuromodulation-based therapies. Here, we sought to investigate the role of stimulation intensity in rats receiving VNS paired with extinction training in a rat model for Posttraumatic Stress Disorder (PTSD). Male Sprague-Dawley rats underwent single prolonged stress followed by a severe fear conditioning training and were implanted with a VNS device. After recovery, independent groups of rats were exposed to extinction training paired with sham (0 mA) or VNS at different intensities (0.4, 0.8, or 1.6 mA). VNS intensities of 0.4 mA or 0.8 mA decreased conditioned fear during extinction training compared to sham stimulation. Pairing extinction training with moderate VNS intensity of 0.8 mA produced significant reduction in conditioned fear during extinction retention when rats were tested a week after VNS-paired extinction. High intensity VNS at 1.6 mA failed to enhance extinction. These findings indicate that a narrow range of VNS intensities enhances extinction learning, and suggest that the 0.8 mA VNS intensity used in earlier rodent and human stroke studies may also be the optimal in using VNS as an adjuvant in exposure therapies for PTSD.


Subject(s)
Extinction, Psychological/physiology , Fear/physiology , Fear/psychology , Vagus Nerve Stimulation/methods , Animals , Male , Rats , Rats, Sprague-Dawley
10.
Trials ; 22(1): 213, 2021 Mar 16.
Article in English | MEDLINE | ID: mdl-33726828

ABSTRACT

BACKGROUND: COPD is a leading cause of death globally, with the majority of morbidity and mortality occurring in low- and middle-income country (LMIC) settings. While tobacco-smoke exposure is the most important risk factor for COPD in high-income settings, household air pollution from biomass smoke combustion is a leading risk factor for COPD in LMICs. Despite the high burden of biomass smoke-related COPD, few studies have evaluated the efficacy of pharmacotherapy in this context. Currently recommended inhaler-based therapy for COPD is neither available nor affordable in most resource-limited settings. Low-dose theophylline is an oral, once-a-day therapy, long used in high-income countries (HICs), which has been proposed for the management of COPD in LMICs in the absence of inhaled steroids and/or bronchodilators. The Low-dose Theophylline for the Management of Biomass-Associated COPD (LODOT-BCOPD) trial investigates the clinical efficacy and cost-effectiveness of low-dose theophylline for the management of biomass-related COPD in a low-income setting. METHODS: LODOT-BCOPD is a randomized, double-blind, placebo-controlled trial to test the efficacy of low-dose theophylline in improving respiratory symptoms in 110 participants with moderate to severe COPD in Central Uganda. The inclusion criteria are as follows: (1) age 40 to 80 years, (2) full-time resident of the study area, (3) daily biomass exposure, (4) post-bronchodilator FEV1/FVC below the 5th percentile of the Global Lung Initiative mixed ethnic reference population, and (5) GOLD Grade B-D COPD. Participants will be randomly assigned to receive once daily low-dose theophylline (200 mg ER, Unicontin-E) or placebo for 52 weeks. All participants will receive education about self-management of COPD and rescue salbutamol inhalers. We will measure health status using the St. George's Respiratory Questionnaire (SGRQ) and quality of life using the EuroQol-5D (EQ-5D) at baseline and every 6 months. In addition, we will assess household air pollution levels, serum inflammatory biomarkers (fibrinogen, hs-CRP), and theophylline levels at baseline, 1 month, and 6 months. The primary outcome is change in SGRQ score at 12 months. Lastly, we will assess the cost-effectiveness of the intervention by calculating quality-adjusted life years (QALYs) from the EQ-5D. TRIAL REGISTRATION: ClinicalTrials.gov  NCT03984188 . Registered on June 12, 2019 TRIAL ACRONYM: Low-dose Theophylline for the Management of Biomass-Associated COPD (LODOT-BCOPD).


Subject(s)
Pulmonary Disease, Chronic Obstructive , Theophylline , Adult , Aged , Aged, 80 and over , Biomass , Bronchodilator Agents/adverse effects , Double-Blind Method , Humans , Middle Aged , Pulmonary Disease, Chronic Obstructive/diagnosis , Pulmonary Disease, Chronic Obstructive/drug therapy , Quality of Life , Randomized Controlled Trials as Topic , Theophylline/adverse effects , Uganda
11.
Ann Am Thorac Soc ; 18(8): 1298-1305, 2021 08.
Article in English | MEDLINE | ID: mdl-33476252

ABSTRACT

Rationale: The majority of the morbidity and mortality related to chronic obstructive pulmonary disease (COPD) occurs in low- and middle-income countries (LMICs). Despite the increasing burden of COPD, disease-specific knowledge among healthcare workers and patients in LMICs remains limited. COPD knowledge questionnaires (COPD-KQ) are valid and reliable tools to assess COPD knowledge and can be employed in settings with limited health literacy. Objectives: To develop and assess the validity and reliability of a COPD-KQ among individuals with COPD in three LMIC settings. Methods: Twelve questions were generated by an expert team of 16 researchers, physicians, and public health professionals to create an LMIC-specific COPD-KQ. The content was based on previous instruments, clinical guidelines, focus-group discussions, and questionnaire piloting. Participants with COPD completed the questionnaire across three diverse LMIC settings before and 3 months after delivery of a standardized COPD-specific education package by a local community health worker trained to deliver the education to an appropriate standard. We used paired t tests to assess improvement in knowledge after intervention. Results: Questionnaire development initially yielded 52 items. On the basis of community feedback and expertise, items were eliminated and added, yielding a final 12-item questionnaire, with a maximum total score of 12. A total of 196 participants with COPD were included in this study in Nepal (n = 86), Peru (n = 35), and Uganda (n = 75). The mean ± standard deviation baseline score was 8.0 ± 2.5, and 3 months after education, the mean score was 10.2 ± 1.7. The community health worker-led COPD educational intervention improved COPD knowledge among community members by 2.2 points (95% confidence interval, 1.8-2.6 points; t = 10.9; P < 0.001). Internal consistency using Cronbach's α was 0.75. Conclusions: The LMIC COPD-KQ demonstrates face and content validity and acceptable internal consistency through development phases, suggesting a reliable and valid COPD education instrument that can be used to assess educational interventions across LMIC settings. Clinical trial registered with www.clinicaltrials.gov (NCT03365713).


Subject(s)
Health Literacy , Pulmonary Disease, Chronic Obstructive , Developing Countries , Humans , Pulmonary Disease, Chronic Obstructive/therapy , Reproducibility of Results , Surveys and Questionnaires
12.
J Rural Health ; 37(3): 602-623, 2021 06.
Article in English | MEDLINE | ID: mdl-33305886

ABSTRACT

PURPOSE: Appalachian residents have higher cancer prevalence and invasive cancer incidence in almost all cancer types relative to non-Appalachian residents. Public health interventions have been carried out to increase preventive cancer screening participation. However, no studies have evaluated the effectiveness of existing interventions targeting cancer screening uptake in this high-risk population. The main objective of this study is to assess the effectiveness of interventions aimed at increasing uptake and/or continuing participation in screened cancers (breast, cervical, colorectal, lung, and prostate) in Appalachia. METHODS: We conducted a systematic review of electronic databases and gray literature using a combination of MeSH and free-text search terms related to breast, cervical, colorectal, lung, and prostate cancer; mass screening; health promotion; and Appalachia. We identified 3,014 articles of which 15 articles were included. We assessed methodological quality using validated tools and analyzed findings using narrative synthesis. FINDINGS: Fifteen studies reported uptake and/or continued participation in screening interventions; these focused on cervical (n = 7), colorectal (n = 5), breast (n = 2), and lung (n = 1) cancers in Appalachia. Interventions included diverse components: mass media campaigns, community outreach events, community health workers, interpersonal counseling, and educational materials. We found that multi-strategy interventions had higher screening uptake relative to interventions employing 1 intervention strategy. Studies that targeted noncompliant populations and leveraged existing community-based organization partnerships had a substantial increase in screening participation versus others. CONCLUSIONS: There is an urgent need for further research and implementation of effective cancer prevention and screening interventions to reduce disparities in cancer morbidity and mortality in Appalachian populations.


Subject(s)
Early Detection of Cancer , Neoplasms , Appalachian Region/epidemiology , Health Promotion , Humans , Male , Mass Screening , Neoplasms/diagnosis , Neoplasms/epidemiology , Neoplasms/prevention & control
13.
Health Educ Res ; 35(4): 258-269, 2020 08 01.
Article in English | MEDLINE | ID: mdl-32702133

ABSTRACT

More than 90% of chronic obstructive pulmonary disease (COPD)-related deaths occur in low- and middle-income countries; however, few studies have examined the illness experiences of individuals living with and providing treatment for COPD in these settings. This study characterizes illness representations for COPD in Nakaseke, Uganda from the perspectives of health care providers, village health teams and community members (CMs) with COPD. We conducted 40 in-depth, semi-structured interviews (16 health care providers, 12 village health teams and 12 CMs, aged 25-80 years). Interviews were analyzed using inductive coding, and the Illness Representations Model guided our analysis. Stakeholder groups showed concordance in identifying causal mechanisms of COPD, but showed disagreement in reasons for care seeking behaviors and treatment preferences. CMs did not use a distinct label to differentiate COPD from other respiratory illnesses, and described both the physical and social consequences of COPD. Local representations can inform development of adapted educational and self-management tools for COPD.


Subject(s)
Health Education , Pulmonary Disease, Chronic Obstructive , Research Design , Adult , Aged , Aged, 80 and over , Female , Health Education/methods , Health Education/standards , Humans , Male , Middle Aged , Pulmonary Disease, Chronic Obstructive/prevention & control , Pulmonary Disease, Chronic Obstructive/therapy , Rural Population , Uganda
14.
Article in English | MEDLINE | ID: mdl-31863872

ABSTRACT

Vagus nerve stimulation (VNS) has shown promise as an adjuvant treatment for posttraumatic stress disorder (PTSD), as it enhances fear extinction and reduces anxiety symptoms in multiple rat models of this condition. Yet, identification of the optimal stimulation paradigm is needed to facilitate clinical translation of this potential therapy. Using an extinction-resistant rat model of PTSD, we tested whether varying VNS intensity and duration could maximize extinction learning while minimizing the total amount of stimulation. We confirmed that sham rats failed to extinguish after a week of extinction training. Delivery of the standard LONG VNS trains (30 s) at 0.4 mA enhanced extinction and reduced anxiety but did not prevent fear return. Increasing the intensity of LONG VNS trains to 0.8 mA prevented fear return and attenuated anxiety symptoms. Interestingly, delivering 1, 4 or 16 SHORT VNS bursts (0.5 s) at 0.8 mA during each cue presentation in extinction training also enhanced extinction. LONG VNS trains or multiple SHORT VNS bursts at 0.8 mA attenuated fear renewal and reinstatement, promoted extinction generalization and reduced generalized anxiety. Delivering 16 SHORT VNS bursts also facilitated extinction in fewer trials. This study provides the first evidence that brief bursts of VNS can enhance extinction training, reduce relapse and support symptom remission using much less VNS than previous protocols. These findings suggest that VNS parameters can be adjusted in order to minimize total charge delivery and maximize therapeutic effectiveness.


Subject(s)
Extinction, Psychological/physiology , Stress Disorders, Post-Traumatic/psychology , Stress Disorders, Post-Traumatic/therapy , Vagus Nerve Stimulation/methods , Animals , Male , Rats , Rats, Sprague-Dawley , Stress Disorders, Post-Traumatic/physiopathology
15.
J Affect Disord ; 265: 552-557, 2020 03 15.
Article in English | MEDLINE | ID: mdl-31784117

ABSTRACT

BACKGROUND: Chronic vagus nerve stimulation (VNS) attenuates anxiety in rats and humans. However, it is unclear whether VNS can promote acute anxiolytic effects. Here we examined short-term anxiolytic effects of VNS using single or multiple trains in rats submitted to a battery of tests. METHODS: Three groups of rats were implanted with VNS cuffs and tested for anxiety using the elevated plus maze (EPM), novelty suppressed feeding (NSF), and acoustic startle response (ASR), after receiving either one or five VNS trains (0.4 mA/30 Hz/30­sec), or sham stimulation. RESULTS: Both single and multiple VNS trains reduced state anxiety as measured using the EPM, but only multiple trains reduced anxiety in the EPM and NSF. VNS did not decrease arousal as measured using the ASR. LIMITATIONS: The anxiolytic effects of VNS may be differently influenced by test order or prior-exposure to stress. VNS did not affect startle responses in naïve rats but the present findings do not determine whether VNS would affect startle responses that are potentiated by fear or anxiety. CONCLUSION: A single VNS train can produce an anxiolytic-like effect in the EPM minutes later, an effect that is not observed in the NSF. Delivering 5 VNS trains restores the immediate effects across tests of anxiety, indicating that more trains produce a more robust anxiolytic effect. The lack of effects on ASR suggests that VNS affects state anxiety but not baseline arousal in naïve rats. We suggest that the anxiolytic effect of VNS can increase tolerability and reduce dropout in exposure-based therapies.


Subject(s)
Anti-Anxiety Agents , Vagus Nerve Stimulation , Animals , Anti-Anxiety Agents/pharmacology , Anxiety/therapy , Fear , Rats , Reflex, Startle , Vagus Nerve
16.
Stress ; 22(4): 509-520, 2019 07.
Article in English | MEDLINE | ID: mdl-31010369

ABSTRACT

We have shown that vagus nerve stimulation (VNS) enhances extinction of conditioned fear and reduces anxiety in rat models of PTSD using moderate stress. However, it is still unclear if VNS can be effective in enhancing extinction of severe fear after prolonged and repeated trauma. Severe fear was induced in adult male rats by combining single prolonged stress (SPS) and protracted aversive conditioning (PAC). After SPS and PAC procedures, rats were implanted with stimulating cuff electrodes, exposed to five days of extinction training with or without VNS, and then tested for extinction retention, return of fear in a new context and reinstatement. The elevated plus maze, open field and startle were used to test anxiety. Sham rats showed no reduction of fear during extensive extinction training. VNS-paired with extinction training reduced freezing at the last extinction session by 70% compared to sham rats. VNS rats exhibited half as much fear as shams, as well as less fear renewal. Sham rats exhibited significantly more anxiety than naive controls, whereas VNS rats did not. These results demonstrate that VNS enhances extinction and reduces anxiety in a severe model of PTSD that combined SPS and a conditioning procedure that is 30 times more intense than the conditioning procedures in previous VNS studies. The broad utility of VNS in enhancing extinction learning in rats and the strong clinical safety record of VNS suggest that VNS holds promise as an adjuvant to exposure-based therapy in people with PTSD and other complex forms of this condition.


Subject(s)
Extinction, Psychological/physiology , Stress Disorders, Post-Traumatic/psychology , Stress, Psychological/psychology , Vagus Nerve Stimulation/psychology , Vagus Nerve/physiology , Animals , Anxiety/physiopathology , Conditioning, Psychological , Fear/physiology , Learning/physiology , Male , Rats
17.
Chronic Obstr Pulm Dis ; 6(1): 17-28, 2019 Jan 04.
Article in English | MEDLINE | ID: mdl-30775421

ABSTRACT

Introduction: Almost 90% of chronic obstructive pulmonary disease (COPD) deaths occur in low- and middle-income countries (LMICs), where there are large rural populations and access to health care for COPD is poor. The purpose of this study was to compare urban-rural provider experiences regarding systemic facilitators and barriers to COPD management and treatment access. Methods: We conducted a qualitative study using direct observations and in-depth semi-structured interviews with 16 and 10 health care providers in urban Kampala and rural Nakaseke, Uganda, respectively. We analyzed interviews by performing inductive coding using generated topical codes. Results: In both urban and rural districts, exposure to evidence-based practices for COPD diagnosis and treatment was limited. The biomedical definition of COPD is not well distinguished in rural communities and was commonly confused with asthma and other respiratory diseases. Urban and rural participants alike described low availability of medications, limited access to diagnostic tools, poor awareness of the disease, and lack of financial means for medical care as common barriers to seeking and receiving care for COPD. While there was greater access to COPD treatment in urban areas, rural populations faced more pronounced barriers in access to diagnostic equipment, following standard treatment guidelines, and training medical personnel in non-communicable disease (NCD) management and treatment. Conclusion: Our results suggest that health system challenges for the treatment of COPD may disproportionately affect rural areas in Uganda. Implementation of diagnostic and treatment guidelines and training health professionals in COPD, with a special emphasis on rural communities, will assist in addressing these barriers.

18.
Glob Health Epidemiol Genom ; 4: e8, 2019 11 26.
Article in English | MEDLINE | ID: mdl-32047643

ABSTRACT

As urbanization increases in low- and middle-income countries (LMICs), urban populations will be increasingly exposed to a range of environmental risk factors for non-communicable diseases. Inadequate living conditions in urban settings may influence mechanisms that regulate gene expression, leading to the development of non-communicable respiratory diseases. We conducted a systematic review of the literature to assess the relationship between respiratory health and epigenetic factors to urban environmental exposures observed in LMICs using MEDLINE, PubMed, EMBASE, and Google Scholar searching a combination of the terms: epigenetics, chronic respiratory diseases (CRDs), lung development, chronic obstructive airway disease, and asthma. A total of 2835 articles were obtained, and 48 articles were included in this review. We found that environmental factors during early development are related to epigenetic effects that may be associated with a higher risk of CRDs. Epigenetic dysregulation of gene expression of the histone deacetylase (HDAC) and histone acetyltransferase gene families was likely involved in lung health of slum dwellers. Respiratory-related environmental exposures influence HDAC function and deoxyribonucleic acid methylation and are important risk factors in the development of CRD. Additional epigenetic research is needed to improve our understanding of associations between environmental exposures and non-communicable respiratory diseases.


Subject(s)
Asthma/etiology , Environmental Exposure/adverse effects , Epigenesis, Genetic , Pulmonary Disease, Chronic Obstructive/etiology , Urban Population , Developing Countries , Humans , Lung/growth & development , Poverty Areas
19.
Elife ; 72018 03 13.
Article in English | MEDLINE | ID: mdl-29533186

ABSTRACT

Recovery from serious neurological injury requires substantial rewiring of neural circuits. Precisely-timed electrical stimulation could be used to restore corrective feedback mechanisms and promote adaptive plasticity after neurological insult, such as spinal cord injury (SCI) or stroke. This study provides the first evidence that closed-loop vagus nerve stimulation (CLV) based on the synaptic eligibility trace leads to dramatic recovery from the most common forms of SCI. The addition of CLV to rehabilitation promoted substantially more recovery of forelimb function compared to rehabilitation alone following chronic unilateral or bilateral cervical SCI in a rat model. Triggering stimulation on the most successful movements is critical to maximize recovery. CLV enhances recovery by strengthening synaptic connectivity from remaining motor networks to the grasping muscles in the forelimb. The benefits of CLV persist long after the end of stimulation because connectivity in critical neural circuits has been restored.


Subject(s)
Electric Stimulation , Neurotransmitter Agents/therapeutic use , Spinal Cord Injuries/rehabilitation , Stroke Rehabilitation/methods , Animals , Female , Forelimb/physiopathology , Hand Strength/physiology , Humans , Motor Cortex/physiopathology , Neuronal Plasticity/physiology , Rats , Recovery of Function/physiology , Spinal Cord/physiopathology , Spinal Cord Injuries/physiopathology , Spinal Cord Injuries/therapy , Stroke/physiopathology , Stroke/therapy , Teach-Back Communication
20.
J Neurosci Methods ; 298: 54-65, 2018 03 15.
Article in English | MEDLINE | ID: mdl-29452180

ABSTRACT

BACKGROUND: Fear conditioning (FC) in rodents is the most used animal model to investigate the neurobiology of posttraumatic stress disorder (PTSD). Although research using FC has generated a better understanding of fear memories, studies often rely on mild or moderate FC training and behavioral analysis generally focuses on measuring freezing responses within few test sessions. NEW METHOD: We introduce the M-Maze task, a system that measures extinction of conditioned fear using suppression of operant behavior. The apparatus consists of an M-shaped maze where rats are trained to alternate nose poking at two pellet dispensers. Proximity sensors measure the animal's locomotion, as well as the latencies and number of operant behaviors. Here we also describe the protracted aversive conditioning (PAC), a rat model of severe fear that induces resistant extinction following a 4-day conditioning protocol that combines delay, unpredictable, and short- and long-trace conditioning. RESULTS: An intense one-day auditory FC protocol induced a sharp elevation in transit time and suppression of nose pokes by conditioned cues, but in contrast to what is found in PTSD patients, fear extinction was rapidly observed. On the other hand, PAC alone or in combination with exposure to single prolonged stress induced persistent extinction impairments in M-Maze tests, as well as enhanced anxiety, and social withdrawal. COMPARISON WITH OTHER EXISTING METHODS: The M-Maze task is fully automated and allows multiple animals to be tested simultaneously in long-term experiments. Moreover, PAC training can be an alternative approach to study extinction-resistant fear. CONCLUSIONS: The M-Maze task allows rapid and unbiased measurements of fear-induced suppression. We suggest that long-term assessment of extinction impairments would lead to a better understanding of the neurobiology of persistent fear and the screening for new therapies.


Subject(s)
Automation, Laboratory , Avoidance Learning , Conditioning, Psychological , Fear , Maze Learning , Memory , Animals , Auditory Perception , Automation, Laboratory/instrumentation , Automation, Laboratory/methods , Disease Models, Animal , Electroshock , Equipment Design , Extinction, Psychological , Male , Motor Activity , Psychological Tests , Rats, Sprague-Dawley , Reflex, Startle , Social Behavior , Stress Disorders, Post-Traumatic
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