Screening for Obstructive Sleep Apnea in Hospitalized Transient Ischemic Attack Stroke Patients Using the STOP-Bang Questionnaire

Frequency of and Factors Associated With Obstructive Sleep Apnea and Periodic Limb Movements in Stroke and TIA Patients

INTRODUCTION

Obstructive sleep apnea (OSA) and periodic limb movements (PLMs) have been associated with an increased risk of cardiovascular disease. There is limited data on the relationship between OSA and PLMs with atrial fibrillation and resistant hypertension in stroke and transient ischemic attack (TIA) patients.

METHODS

Consecutive stroke and TIA patients referred by a vascular neurologist for diagnostic polysomnography (PSG) from September 1, 2012 to August 31, 2015 were included in a retrospective analysis. Baseline clinical characteristics, PSG results and outcomes were collected to identify the frequency of and factors associated with PLMs (mild 5 to 10/h; severe ≥15/h), PLM arousals (≥5/h) and moderate-severe OSA (apna-hypopnea Index ≥15) including atrial fibrillation and resistant hypertension.

RESULTS

Among 103 patients (mean age, 60±15 y; 50% female; 61% nonwhites; 77% ischemic stroke; 23% resistant hypertension) who underwent PSG, 20% had mild PLMs, 28% had severe PLMs, 14% had PLM arousals, and 22% had moderate-severe OSA. Factors associated with moderate-severe OSA included older age (odds ratio, 1.06; 95% confidence interval, 1.02-1.11) and presence of atrial fibrillation (odds ratio, 4.26; 95% confidence interval, 1.17-15.44). Nonwhite race was associated with lower likelihood of mild and severe PLMs, whereas female sex was associated with lower likelihood of PLM arousals. OSA and PLMs were not associated with resistant hypertension.

CONCLUSIONS

A significant number of stroke and TIA patients who underwent PSG have PLMs and moderate-severe OSA. Stroke and TIA patients with atrial fibrillation are more likely to have moderate-severe OSA and may benefit from PSG evaluation.

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.