Effect of Clothing Fabric on 20-km Cycling Performance in Endurance Athletes.

Purpose: Examine the effect of synthetic fabrics (SYN, 60% polyester: 40% nylon) vs. 100% cotton fabric (CTN) on the 20-km cycling time trial (20 kmCTT) performance of competitive cyclists and triathletes. Methods: In this randomized controlled crossover study, 15 adults (5 women) aged 29.6 ± 2.7 years (mean ± SE) with a peak rate of O2 consumption of 60.0 ± 2.0 ml/kg/min completed a 20 kmCTT under ambient laboratory conditions (24.3 ± 0.7°C and 17 ± 7% relative humidity) with a simulated wind of ~3 m/s while wearing SYN or CTN clothing ensembles. Both ensembles were of snowflake mesh bi-layer construction and consisted of a loose-fitting long-sleeved shirt with full-length trousers. Results: Participants maintained a significantly (p < 0.05) higher cycling speed and power output over the last 6-km of the 20 kmCTT while wearing the SYN vs. CTN ensemble (e.g., by 0.98 km/h and 18.4 watts at the 20-km mark). Consequently, 20 kmCTT duration was significantly reduced by 15.7 ± 6.8 sec or 0.8 ± 0.3% during SYN vs. CTN trials (p < 0.05). Improved 20 kmCTT performance with SYN vs. CTN clothing could not be explained by concurrent differences in esophageal temperature, sweat rate, ratings of perceived exertion and/or cardiometabolic responses to exercise. However, it was accompanied by significantly lower mean skin temperatures (~1°C) and more favorable ratings of perceived clothing comfort and thermal sensation during exercise. Conclusion: Under the experimental conditions of the current study, athletic clothing made of synthetic fabrics significantly improved the 20 kmCTT performance of endurance-trained athletes by optimizing selected thermoregulatory and perceptual responses to exercise.

Empowering Implementation Teams with a Learning Health System Approach: Leveraging Data to Improve Quality of Care for Transient Ischemic Attack.

BACKGROUND: Questions persist about how learning healthcare systems should integrate audit and feedback (A&F) into quality improvement (QI) projects to support clinical teams' use of performance data to improve care quality. OBJECTIVE: To identify how a virtual "Hub" dashboard that provided performance data for patients with transient ischemic attack (TIA), a resource library, and a forum for sharing QI plans and tools supported QI activities among newly formed multidisciplinary clinical teams at six Department of Veterans Affairs (VA) medical centers. DESIGN: An observational, qualitative evaluation of how team members used a web-based Hub. PARTICIPANTS: External facilitators and multidisciplinary team members at VA facilities engaged in QI to improve the quality of TIA care. APPROACH: Qualitative implementation process and summative evaluation of observational Hub data (interviews with Hub users, structured field notes) to identify emergent, contextual themes and patterns of Hub usage. KEY RESULTS: The Hub supported newly formed multidisciplinary teams in implementing QI plans in three main ways: as an information interface for integrated monitoring of TIA performance; as a repository used by local teams and facility champions; and as a tool for team activation. The Hub enabled access to data that were previously inaccessible and unavailable and integrated that data with benchmark and scientific evidence to serve as a common data infrastructure. Led by champions, each implementation team used the Hub differently: local adoption of the staff and patient education materials; benchmarking facility performance against national rates and peer facilities; and positive reinforcement for QI plan development and monitoring. External facilitators used the Hub to help teams leverage data to target areas of improvement and disseminate local adaptations to promote resource sharing across teams. CONCLUSIONS: As a dynamic platform for A&F operating within learning health systems, hubs represent a promising strategy to support local implementation of QI programs by newly formed, multidisciplinary teams.

Evaluating the feasibility of implementing a Telesleep pilot program using two-tiered external facilitation.

BACKGROUND: Obstructive sleep apnea (OSA) can negatively impact patients' health status and outcomes. Positive airway pressure (PAP) reverses airway obstruction and may reduce the risk of adverse outcomes. Remote monitoring of PAP (as opposed to in-person visits) may improve access to sleep medicine services. This study aimed to evaluate the feasibility of implementing a clinical program that delivers treatment for OSA through PAP remote monitoring using external facilitation as an implementation strategy. METHODS: Participants included patients with OSA at a Veteran Affairs Medical Center (VAMC). PAP adherence and clinical disease severity on treatment (measured by the apnea hypopnea index [AHI]) were the preliminary effectiveness outcomes across two delivery models: usual care (in-person) and Telehealth nurse-delivered remote monitoring. We also assessed visit duration and travel distance. A prospective, mixed-methods evaluation examined the two-tiered external facilitation implementation strategy. RESULTS: The pilot project included N = 52 usual care patients and N = 38 Telehealth nurse-delivered remote monitoring patients. PAP adherence and disease severity were similar across the delivery modalities. However, remote monitoring visits were 50% shorter than in-person visits and saved a mean of 72 miles of travel (median = 45.6, SD = 59.0, mode = 17.8, range 5.4-220). A total of 62 interviews were conducted during implementation with a purposive sample of 12 clinical staff involved in program implementation. Weekly external facilitation delivered to both front-line staff and supervisory physicians was necessary to ensure patient enrollment and treatment. Synchronized, "two-tiered" facilitation at the executive and coordinator levels proved crucial to developing the clinical and administrative infrastructure to support a PAP remote monitoring program and to overcome implementation barriers. CONCLUSIONS: Remote PAP monitoring had similar efficacy to in-person PAP services in this Veteran population. Although external facilitation is a widely-recognized implementation strategy in quality improvement projects, less is known about how multiple facilitators work together to help implement complex programs. Two-tiered facilitation offers a model well-suited to programs where innovations span disciplines, disrupt professional hierarchies (such as those between service chiefs, clinicians, and technicians) and bring together providers who do not know each other, yet must collaborate to improve access to care.

Polysomnography Utilization in Veterans Presenting Acutely with Ischemic Stroke or Transient Ischemic Attack.

INTRODUCTION: Obstructive sleep apnea (OSA) is an independent cerebrovascular risk factor and highly prevalent in patients with ischemic stroke and transient ischemic attack (TIA). Timely diagnosis and treatment of OSA is important as clinical data suggest that treatment of OSA in the setting of acute ischemic stroke improves functional outcomes. We aimed to assess polysomnography (PSG) utilization in US. Veterans with acute stroke or TIA over a 2-year period. METHODS: Veterans with acute ischemic stroke or TIA presenting to a Veterans Administration Medical Center (VAMC) between October 1, 2015, and June 30, 2017, were included. Demographic, clinical data, and PSG within 12 months of hospital discharge were obtained from the VA Corporate Data Warehouse to determine the rate of PSG testing among those with acute ischemic stroke or TIA. Fisher's exact test and two-sample t tests were used to compare demographic and clinical characteristics for those receiving and not receiving PSG. Mixed effect logistic regression was used to model the association of clinical and demographic characteristics with PSG receipt. RESULTS: In fiscal years (FYs) 2016 and 2017, 9,200 Veterans were admitted to a VAMC with ischemic stroke (6,011) or TIA (3,089). Veterans were elderly (70.5 ± 11.1 years), predominantly male (95.7%), and largely Caucasian (68.0% Caucasian, 26.3% African-American). Just 6.0% of Veterans underwent PSG within 1 year of acute ischemic stroke or TIA in FY 2016, compared to 6.2% in FY 2017 (p = 0.72). Compared to Veterans ≥80 years, those <60 had adjusted OR of 6.73 (4.10-11.05), those 60-69 had OR 4.29 (2.73-6.74), and those 70-79 had OR 2.63 (1.66-4.18) of having PSG. Veterans with diabetes or heart failure had significantly higher odds, whereas those with dementia had significantly lower odds of receiving PSG. CONCLUSION: PSG utilization among US Veterans is low and stable over time, despite recent guidelines recommending PSG among those having stroke or TIA. Older Veterans and those with dementia were unlikely to get PSG, representing especially vulnerable populations.

Adapting Continuous Positive Airway Pressure Therapy to Where Patients Live: A Comparative Case Study.

Objectives Continuous positive airway pressure (CPAP) therapy has been demonstrated to effectively reverse the abnormal physiology of sleep apnea and improve a variety of patient outcomes, yet helping patients adapt and adhere to CPAP has proven to be a challenging issue in the effective treatment of obstructive sleep apnea (OSA). As a home-based intervention trial, the "Sleep Apnea in Transient Ischemic Attack and Stroke: Reducing Cardiovascular Risk with Positive Airway Pressure" ("sleep tight") study was uniquely positioned to capture and evaluate challenges faced by patients over time during their introduction to CPAP therapy.  Methods A comparative case study design was used to better understand the process whereby patients adapted CPAP therapy in order to fit their own personal set of circumstances. Cases were identified from patients enrolled in the "enhanced intervention" group of the sleep tight trial.  Results These comparative case studies illustrated how adherence to CPAP therapy is an adaptive process where personal context matters. The case studies also demonstrated how some patients overcame challenges and barriers by themselves to integrate CPAP therapy into their own lives, while others required help from study staff to overcome these barriers and some were never able to successfully adapt CPAP therapy in order to fit their personal contexts, despite study staffs' best efforts.  Conclusions A major opportunity to improve CPAP adherence appears to exist in placing greater emphasis on supporting patients in adapting CPAP therapy for "where they live."

Uncertainty as a Key Influence in the Decision To Admit Patients with Transient Ischemic Attack.

BACKGROUND: Patients with transient ischemic attacks (TIA) are at high risk of subsequent vascular events. Hospitalization improves quality of care, yet admission rates for TIA patients vary considerably. OBJECTIVES: We sought to identify factors associated with the decision to admit patents with TIA. DESIGN: We conducted a secondary analysis of a prior study's data including semi-structured interviews, administrative data, and chart review. PARTICIPANTS: We interviewed multidisciplinary clinical staff involved with TIA care. Administrative data included information for TIA patients in emergency departments or inpatient settings at VA medical centers (VAMCs) for fiscal years (FY) 2011 and 2014. Chart reviews were conducted on a subset of patients from 12 VAMCs in FY 2011. APPROACH: For the qualitative data, we focused on interviewees' responses to the prompt: "Tell me what influences you in the decision to or not to admit TIA patients." We used administrative data to identify admission rates and chart review data to identify ABCD2 scores (a tool to classify stroke risk after TIA). KEY RESULTS: Providers' decisions to admit TIA patients were related to uncertainty in several domains: lack of a facility TIA-specific policy, inconsistent use of ABCD2 score, and concerns about facilities' ability to complete a timely workup. There was a disconnect between staff perceptions about TIA admission and facility admission rates. According to chart review data, staff at facilities with higher admission rates in FY 2011 reported consistent reliance on ABCD2 scores and related guidelines in admission decision-making. CONCLUSIONS: Many factors contributed to decisions regarding admitting a patient with TIA; however, clinicians' uncertainty appeared to be a key driver. Further quality improvement interventions for TIA care should focus on facility adoption of TIA protocols to address uncertainty in TIA admission decision-making and to standardize timely evaluation of TIA patients and delivery of secondary prevention strategies.

Diagnosing and Treating Sleep Apnea in Patients With Acute Cerebrovascular Disease.

Background Obstructive sleep apnea ( OSA ) is common among patients with acute ischemic stroke and transient ischemic attack. We evaluated whether continuous positive airway pressure for OSA among patients with recent ischemic stroke or transient ischemic attack improved clinical outcomes. Methods and Results This randomized controlled trial among patients with ischemic stroke/transient ischemic attack compared 2 strategies (standard or enhanced) for the diagnosis and treatment of OSA versus usual care over 1 year. Primary outcomes were National Institutes of Health Stroke Scale and modified Rankin Scale scores. Among 252 patients (84, control; 86, standard; 82, enhanced), OSA prevalence was as follows: control, 69%; standard, 74%; and enhanced, 80%. Continuous positive airway pressure use occurred on average 50% of nights and was similar among standard (3.9±2.1 mean hours/nights used) and enhanced (4.3±2.4 hours/nights used; P=0.46) patients. In intention-to-treat analyses, changes in National Institutes of Health Stroke Scale and modified Rankin Scale scores were similar across groups. In as-treated analyses among patients with OSA, increasing continuous positive airway pressure use was associated with improved National Institutes of Health Stroke Scale score (no/poor, -0.6±2.9; some, -0.9±1.4; good, -0.3±1.0; P=0.0064) and improved modified Rankin Scale score (no/poor, -0.3±1.5; some, -0.4±1.0; good, -0.9±1.2; P=0.0237). In shift analyses among patients with OSA, 59% of intervention patients had best neurological symptom severity (National Institutes of Health Stroke Scale score, 0-1) versus 38% of controls ( P=0.038); absolute risk reduction was 21% (number needed to treat, 4.8). Conclusions Although changes in neurological functioning and functional status were similar across the groups in the intention-to-treat analyses, continuous positive airway pressure use was associated with improved neurological functioning among patients with acute ischemic stroke/transient ischemic attack with OSA . Clinical Trial Registration URL: http://www.clinicaltrials.gov . Unique identifier: NCT 01446913.

Receipt of cardiac screening does not influence 1-year post-cerebrovascular event mortality.

BACKGROUND: American Heart Association/American Stroke Association expert consensus guidelines recommend consideration of cardiac stress testing to screen for occult coronary heart disease (CHD) among patients with ischemic stroke/TIA who have a high-risk Framingham Cardiac Risk Score (FCRS). Whether this guideline is being implemented in routine clinical practice, and the association of its implementation with mortality, is less clear. METHODS: Study participants were Veterans with stroke/TIA (n = 11,306) during fiscal year 2011 who presented to a VA Emergency Department or who were admitted. Patients were excluded (n = 6,915) based on prior CHD/angina/chest pain history, receipt of cardiac stress testing within 18 months prior to cerebrovascular event, death within 90 days of discharge, discharge to hospice, transfer to a non-VA acute care facility, or missing/unknown race. FCRS ≥20% was classified as high risk for CHD. ICD-9 and Common Procedural Terminology codes were used to identify receipt of any cardiac stress testing. RESULTS: Among 4,391 eligible patients, 62.8% (n = 2,759) had FCRS ≥20%. Cardiac stress testing was performed infrequently and in similar proportion among high-risk (4.5% [123/2,759]) vs low/intermediate-risk (4.4% [72/1,632]) patients (adjusted odds ratio [aOR] 0.77, 95% confidence interval [CI] 0.54-1.10). Receipt of stress testing was not associated with reduced 1-year mortality (aOR 0.59, CI 0.26-1.30). CONCLUSIONS: In this observational cohort study of patients with cerebrovascular disease, cardiac screening was relatively uncommon and was not associated with 1-year mortality. Additional work is needed to understand the utility of CHD screening among high-risk patients with cerebrovascular disease.

Quality of Care for Veterans With Transient Ischemic Attack and Minor Stroke.

Importance: The timely delivery of guideline-concordant care may reduce the risk of recurrent vascular events for patients with transient ischemic attack (TIA) and minor stroke. Although many health care organizations measure stroke care quality, few evaluate performance for patients with TIA or minor stroke, and most include only a limited subset of guideline-recommended processes. Objective: To assess the quality of guideline-recommended TIA and minor stroke care across the Veterans Health Administration (VHA) system nationwide. Design, Setting, and Participants: This cohort study included 8201 patients with TIA or minor stroke cared for in any VHA emergency department (ED) or inpatient setting during federal fiscal year 2014 (October 1, 2013, through September 31, 2014). Patients with length of stay longer than 6 days, ventilator use, feeding tube use, coma, intensive care unit stay, inpatient rehabilitation stay before discharge, or receipt of thrombolysis were excluded. Outlier facilities for each process of care were identified by constructing 95% CIs around the facility pass rate and national pass rate sites when the 95% CIs did not overlap. Data analysis occurred from January 16, 2016, through June 30, 2017. Main Outcomes and Measures: Ten elements of care were assessed using validated electronic quality measures. Results: In the 8201 patients included in the study (mean [SD] age, 68.8 [11.4] years; 7877 [96.0%] male; 4856 [59.2%] white), performance varied across elements of care: brain imaging by day 2 (6720/7563 [88.9%]; 95% CI, 88.2%-89.6%), antithrombotic use by day 2 (6265/7477 [83.8%]; 95% CI, 83.0%-84.6%), hemoglobin A1c measurement by discharge or within the preceding 120 days (2859/3464 [82.5%]; 95% CI, 81.2%-83.8%), anticoagulation for atrial fibrillation by day 7 after discharge (1003/1222 [82.1%]; 95% CI, 80.0%-84.2%), deep vein thrombosis prophylaxis by day 2 (3253/4346 [74.9%]; 95% CI, 73.6%-76.2%), hypertension control by day 90 after discharge (4292/5979 [71.8%]; 95% CI, 70.7%-72.9%), neurology consultation by day 1 (5521/7823 [70.6%]; 95% CI, 69.6%-71.6%), electrocardiography by day 2 or within 1 day prior (5073/7570 [67.0%]; 95% CI, 65.9%-68.1%), carotid artery imaging by day 2 or within 6 months prior (4923/7685 [64.1%]; 95% CI, 63.0%-65.2%), and moderate- to high-potency statin prescription by day 7 after discharge (3329/7054 [47.2%]; 95% CI, 46.0%-48.4%). Performance varied substantially across facilities (eg, neurology consultation had a facility outlier rate of 53.0%). Performance was higher for admitted patients than for patients cared for only in EDs with the greatest disparity for carotid artery imaging (4478/5927 [75.6%] vs 445/1758 [25.3%]; P < .001). Conclusions and Relevance: This national study of VHA system quality of care for patients with TIA or minor stroke identified opportunities to improve care quality, particularly for patients who were discharged from the ED. Health care systems should engage in ongoing TIA care performance assessment to complement existing stroke performance measurement.

Barriers and facilitators to provide quality TIA care in the Veterans Healthcare Administration.

OBJECTIVE: To identify key barriers and facilitators to the delivery of guideline-based care of patients with TIA in the national Veterans Health Administration (VHA). METHODS: We conducted a cross-sectional, observational study of 70 audiotaped interviews of multidisciplinary clinical staff involved in TIA care at 14 VHA hospitals. We de-identified and analyzed all transcribed interviews. We identified emergent themes and patterns of barriers to providing TIA care and of facilitators applied to overcome these barriers. RESULTS: Identified barriers to providing timely acute and follow-up TIA care included difficulties accessing brain imaging, a constantly rotating pool of housestaff, lack of care coordination, resource constraints, and inadequate staff education. Key informants revealed that both stroke nurse coordinators and system-level factors facilitated the provision of TIA care. Few facilities had specific TIA protocols. However, stroke nurse coordinators often expanded upon their role to include TIA. They facilitated TIA care by (1) coordinating patient care across services, communicating across service lines, and educating clinical staff about facility policies and evidence-based practices; (2) tracking individual patients from emergency departments to inpatient settings and to discharge for timely follow-up care; (3) providing and referring TIA patients to risk factor management programs; and (4) performing regular audit and feedback of quality performance data. System-level facilitators included clinical service leadership engagement and use of electronic tools for continuous care across services. CONCLUSIONS: The local organization within a health care facility may be targeted to cultivate internal facilitators and a systemic infrastructure to provide evidence-based TIA care.

Development and Validation of Electronic Quality Measures to Assess Care for Patients With Transient Ischemic Attack and Minor Ischemic Stroke.

BACKGROUND: Despite interest in using electronic health record (EHR) data to assess quality of care, the accuracy of such data is largely unknown. We sought to develop and validate transient ischemic attack and minor ischemic stroke electronic quality measures (eQMs) using EHR data. METHODS AND RESULTS: A random sample of patients with transient ischemic attack or minor ischemic stroke, cared for in Veterans Health Administration facilities (fiscal year 2011), was identified. We constructed 31 eQMs based on existing quality measures. Chart review was the criterion standard for validating the eQMs. To evaluate eQMs in terms of eligibility, we calculated the proportion of patients who were genuinely not eligible to receive a process (based on chart review) and who were correctly identified as not eligible by the EHR data (specificity). To assess eQMs about classification of whether patients received a process, we calculated the proportion of patients who actually received the process (based on chart review) and who were classified correctly by the EHR data as passing (sensitivity). Seven hundred sixty-three patients were included. About eligibility, specificity varied from 25% (brain imaging; carotid imaging) to 99% (anticoagulation quality). About pass rates, sensitivity varied from 30% (antihypertensive class) to 100% (coronary risk assessment; international normalized ratio measured). The 16 eQMs with ≥70% specificity in eligibility and ≥70% sensitivity in pass rates included coronary risk assessment, international normalized ratio measured, HbA1c measurement, speech language pathology consultation, anticoagulation for atrial fibrillation, discharge on statin, lipid management, neurology consultation, Holter, deep vein thrombosis prophylaxis, oral hypoglycemic intensification, cholesterol medication intensification, antihypertensive intensification, antihypertensive class, carotid stenosis intervention, and substance abuse referral for alcohol. CONCLUSIONS: It is feasible to construct valid eQMs for processes of transient ischemic attack and minor ischemic stroke care. Healthcare systems with EHRs should consider using electronic data to evaluate care for their patients with transient ischemic attack and to complement and expand quality measurement programs currently focused on patients with stroke.

Diagnosing and managing sleep apnea in patients with chronic cerebrovascular disease: a randomized trial of a home-based strategy.

BACKGROUND: Obstructive sleep apnea is common and associated with poor outcomes after stroke or transient ischemic attack (TIA). We sought to determine whether the intervention strategy improved sleep apnea detection, obstructive sleep apnea (OSA) treatment, and hypertension control among patients with chronic cerebrovascular disease and hypertension. METHODS: In this randomized controlled strategy trial intervention, patients received unattended polysomnography at baseline, and patients with OSA (apnea-hypopnea index ≥5 events/h) received auto-titrating continuous positive airway pressure (CPAP) for up to 1 year. Control patients received usual care and unattended polysomnography at the end of the study, to identify undiagnosed OSA. Both groups received 24-h blood pressure assessments at baseline and end of the study. "Excellent" CPAP adherence was defined as cumulative use of ≥4 h/night for ≥70% of the nights. RESULTS: Among 225 randomized patients (115 control; 110 intervention), 61.9% (120/194) had sleep apnea. The strategy successfully diagnosed sleep apnea with 97.1% (102/105) valid studies; 90.6% (48/53, 95% CI 82.7-98.4%) of sleep apnea was undiagnosed among control patients. The intervention improved long-term excellent CPAP use: 38.6% (22/57) intervention versus 0% (0/2) control (p < 0.0001). The intervention did not improve hypertension control in this population with well-controlled baseline blood pressure: intervention, 132.7 mmHg (±standard deviation, 14.1) versus control, 133.8 mmHg (±14.0) (adjusted difference, -1.1 mmHg, 95% CI (-4.2, 2.0)), p = 0.48). CONCLUSIONS: Patients with cerebrovascular disease and hypertension have a high prevalence of OSA. The use of portable polysomnography, and auto-titrating CPAP in the patients' homes, improved both the diagnosis and the treatment for sleep apnea compared with usual care but did not lower blood pressure.

Development, Validation, and Assessment of an Ischemic Stroke or Transient Ischemic Attack-Specific Prediction Tool for Obstructive Sleep Apnea.

BACKGROUND: Screening instruments for obstructive sleep apnea (OSA), as used routinely to guide clinicians regarding patient referral for polysomnography (PSG), rely heavily on symptomatology. We sought to develop and validate a cerebrovascular disease-specific OSA prediction model less reliant on symptomatology, and to compare its performance with commonly used screening instruments within a population with ischemic stroke or transient ischemic attack (TIA). METHODS: Using data on demographic factors, anthropometric measurements, medical history, stroke severity, sleep questionnaires, and PSG from 2 independently derived, multisite, randomized trials that enrolled patients with stroke or TIA, we developed and validated a model to predict the presence of OSA (i.e., Apnea-Hypopnea Index ≥5 events per hour). Model performance was compared with that of the Berlin Questionnaire, Epworth Sleepiness Scale (ESS), the Snoring, Tiredness, Observed apnea, high blood Pressure, Body mass index, Age, Neck circumference, and Gender instrument, and the Sleep Apnea Clinical Score. RESULTS: The new SLEEP Inventory (Sex, Left heart failure, ESS, Enlarged neck, weight [in Pounds], Insulin resistance/diabetes, and National Institutes of Health Stroke Scale) performed modestly better than other instruments in identifying patients with OSA, showing reasonable discrimination in the development (c-statistic .732) and validation (c-statistic .731) study populations, and having the highest negative predictive value of all in struments. CONCLUSIONS: Clinicians should be aware of these limitations in OSA screening instruments when making decisions about referral for PSG. The high negative predictive value of the SLEEP INventory may be useful in determining and prioritizing patients with stroke or TIA least in need of overnight PSG.

The Association between Nocturnal Cardiac Arrhythmias and Sleep-Disordered Breathing: The DREAM Study.

STUDY OBJECTIVES: To determine whether sleep-disordered breathing (SDB) is associated with cardiac arrhythmia in a clinic-based population with multiple cardiovascular comorbidities and severe SDB. METHODS: This was a cross-sectional analysis of 697 veterans who underwent polysomnography for suspected SDB. SDB was categorized according to the apnea-hypopnea index (AHI): none (AHI < 5), mild (5 ≥ AHI < 15), and moderate-severe (AHI ≥ 15). Nocturnal cardiac arrhythmias consisted of: (1) complex ventricular ectopy, (CVE: non-sustained ventricular tachycardia, bigeminy, trigeminy, or quadrigeminy), (2) combined supraventricular tachycardia, (CST: atrial fibrillation or supraventricular tachycardia), (3) intraventricular conduction delay (ICD), (4) tachyarrhythmias (ventricular and supraventricular), and (5) any cardiac arrhythmia. Unadjusted, adjusted logistic regression, and Cochran-Armitage testing examined the association between SDB and cardiac arrhythmias. Linear regression models explored the association between hypoxia, arousals, and cardiac arrhythmias. RESULTS: Compared to those without SDB, patients with moderate-severe SDB had almost three-fold unadjusted odds of any cardiac arrhythmia (2.94; CI 95%, 2.01-4.30; p < 0.0001), two-fold odds of tachyarrhythmias (2.16; CI 95%,1.47-3.18; p = 0.0011), two-fold odds of CVE (2.01; 1.36-2.96; p = 0.003), and two-fold odds of ICD (2.50; 1.58-3.95; p = 0.001). A linear trend was identified between SDB severity and all cardiac arrhythmia subtypes (p value linear trend < 0.0001). After adjusting for age, BMI, gender, and cardiovascular diseases, moderate-severe SDB patients had twice the odds of having nocturnal cardiac arrhythmias (2.24; 1.48-3.39; p = 0.004). Frequency of obstructive respiratory events and hypoxia were strong predictors of arrhythmia risk. CONCLUSIONS: SDB is independently associated with nocturnal cardiac arrhythmias. Increasing severity of SDB was associated with an increasing risk for any cardiac arrhythmia.

Infarct location and sleep apnea: evaluating the potential association in acute ischemic stroke.

BACKGROUND: The literature about the relationship between obstructive sleep apnea (OSA) and stroke location is conflicting with some studies finding an association and others demonstrating no relationship. Among acute ischemic stroke patients, we sought to examine the relationship between stroke location and the prevalence of OSA; OSA severity based on apnea-hypopnea index (AHI), arousal frequency, and measure of hypoxia; and number of central and obstructive respiratory events. METHODS: Data were obtained from patients who participated in a randomized controlled trial (NCT01446913) that evaluated the effectiveness of a strategy of diagnosing and treating OSA among patients with acute ischemic stroke and transient ischemic attack. Stroke location was classified by brain imaging reports into subdivisions of lobes, subcortical areas, brainstem, cerebellum, and vascular territory. The association between acute stroke location and polysomnographic findings was evaluated using logistic regression for OSA presence and negative binomial regression for AHI. RESULTS: Among 73 patients with complete polysomnography and stroke location data, 58 (79%) had OSA. In unadjusted models, no stroke location variable was associated with the prevalence or severity of OSA. Similarly, in multivariable modeling, groupings of stroke location were also not associated with OSA presence. CONCLUSIONS: These results indicate that OSA is present in the majority of stroke patients and imply that stroke location cannot be used to identify a group with higher risk of OSA. The results also suggest that OSA likely predated the stroke. Given this high overall prevalence, strong consideration should be given to obtaining polysomnography for all ischemic stroke patients.

Challenges and motivating factors related to positive airway pressure therapy for post-TIA and stroke patients.

Challenges adapting to continuous positive airway pressure (CPAP) therapy are largely unexplored in patients with stroke or transient ischemic attack. This study, nested within a randomized controlled trial of CPAP use, employed qualitative methods to explore challenges and motivators related to CPAP at two time points: prior to initiating therapy and at a 1-month follow up. Emergent thematic analysis, an inductive, qualitative approach, revealed variations in how patients experienced and adapted to CPAP across five phases: (a) interpreting the sleep apnea diagnosis, (b) contemplating CPAP therapy, (c) trying CPAP therapy, (d) making mid-course adjustments, and (e) experiencing benefits from CPAP therapy. Patients all had mild to moderate sleep apnea, and frequently did not experience sleep apnea symptoms. A salient motivator for adhering to CPAP therapy for these patients was the desire to reduce the risk of subsequent cerebrovascular events. Self-determination theory guided the interpretation of results.

Circumstances and consequences of falls among people with chronic stroke.

Falls are common after stroke; however, circumstances and consequences are relatively unknown. Our objectives were to identify the differences between fallers and non-fallers among people with chronic stroke, identify the circumstances of fall events, and examine the consequences of the falls. This is a secondary data analysis; all participants included sustained a stroke. Variables included demographics, stroke characteristics, and comorbidities. Falls were collected via self-report, and circumstances and consequences were derived from participant description of the event and categorized as appropriate. Among 160 participants, 53 (33%) reported a fall during the 1 yr period. Circumstances of falls were categorized as intrinsic or extrinsic. Location and circumstance of the fall were included: 70% occurred at home and 40% were associated with impaired physical or mental state (e.g., inattention to tying shoes). Additionally, 21% of falls were associated with activities of daily living and mobility and 34% with slips or trips. The majority who fell sustained an injury (72%). Injuries ranged from bruising to fractures, and 55% of those with an injury sought medical care (32% to emergency department). Poststroke falls are associated with an alarming rate of injury and healthcare utilization. Targeting mental and physical states may be key to fall prevention.

Diagnosis and Treatment of Sleep Apnea in patients' homes: the rationale and methods of the "GoToSleep" randomized-controlled trial.

BACKGROUND: The "Diagnosis and Treatment of Sleep Apnea in Cerebrovascular Disease" (GoToSleep) study is evaluating a strategy to improve the diagnosis and treatment of sleep apnea among veterans with stroke or transient ischemic attack (TIA) who also have hypertension. Specifically, the GoToSleep study was designed to overcome some of the barriers that exist within the Veterans Health Administration (VHA) to the timely diagnosis and treatment of sleep apnea by using ambulatory home-based polysomnography and auto-titrating continuous positive airway pressure (CPAP) to reduce the reliance on laboratory-based sleep studies. METHODS: The GoToSleep study is a prospective, multi-site, randomized, controlled strategy trial among an expected 318 veterans with cerebrovascular disease and hypertension who are assigned to an intervention group or a control group. Patients in the intervention group receive unattended polysomnography at baseline, and those with sleep apnea receive auto-titrating CPAP therapy for up to one year. Patients in the control group receive usual care and unattended polysomnography at the end of the study to identify the rate of undiagnosed sleep apnea. The primary objectives of the GoToSleep study are to determine whether a diagnostic and therapeutic intervention strategy among veterans with cerebrovascular disease and hypertension improves: (1) detection of sleep apnea; (2) appropriate treatment for sleep apnea; and (3) control of hypertension. Twenty-four-hour blood pressure assessments are made at baseline and at the end of the one-year study period for both groups. Antihypertensive medications and their doses are recorded at the time of the 24-hour blood pressure measurements. DISCUSSION: This manuscript provides the rationale for 4 key components of the design of the GoToSleep trial: the inclusion of patients with cerebrovascular disease and hypertension without the use of a measure of daytime sleepiness as an eligibility criterion; the use of portable polysomnography and auto-titrating CPAP in patients' homes rather than using sleep laboratory polysomnography with fixed pressure CPAP; the analytic approach to evaluating change in blood pressure in the context of change in antihypertensive medications; and the use of a usual care control group.

Ambulatory blood pressure monitoring among patients with cerebrovascular disease.

BACKGROUND: Although stroke care guidelines endorse the paramount importance of hypertension management, the specific role of ambulatory blood pressure (ABP) monitoring among patients with cerebrovascular disease has not been established. OBJECTIVES: The objectives of this study were to: (a) conduct a systematic review describing the published studies that examined ABP monitoring among patients with cerebrovascular disease and (b) to discuss practical considerations of ABP monitoring among patients with stroke. METHODS: We identified English-language articles that focused on the use of ABP monitoring among patients with cerebrovascular disease. The titles and abstracts of the articles were reviewed to identify whether the study included ABP monitoring and whether the populations studied had evidence of cerebrovascular disease; we excluded two case reports. We used ABP data from patients with cerebrovascular disease enrolled in an ongoing clinical trial to illustrate points related to the application of ABP monitoring in this population. RESULTS: A total of 23 articles met our inclusion criteria. These articles described the use of ABP monitoring for the identification of stroke patients at risk of poor outcomes, including mortality and neurological impairment. They also describe common patterns of blood pressure poststroke; finding that stroke patients often demonstrate a loss of the usual nocturnal fall in blood pressure. Logistical considerations in the use of ABP monitoring for patients with stroke include patients with arm weakness, the minimum number of measurements needed, the determination of nocturnal/rest versus daytime/wake blood pressure values, and the interpretation of extreme values are reviewed. CONCLUSION: Until controlled trial data support interventions based on the ABP data, it is unlikely that guidelines will recommend the routine application of ABP monitoring among patients with stroke.