Charles Austin

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.

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.

Ambulatory blood pressure monitoring among patients with cerebrovascular disease.

BackgroundAlthough 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. ObjectivesThe 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. MethodsWe 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. ResultsA 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. ConclusionUntil 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.

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, 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.

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.