Wake-up stroke is not associated with obstructive sleep apnea

Presence of Self-Reported Sleep Alterations After Stroke and Their Relationship With Disability: A Longitudinal Study

BACKGROUND

Sleep disorders have a prevalence of 30% to 70% in post-stroke individuals. The presence of sleep disorders and poor sleep quality after stroke can affect important functions and lead to worse outcomes. However, most studies are restricted to the acute post-stroke stage only.

OBJECTIVE

To investigate the frequency of self-reported sleep alterations in a sample of chronic stroke individuals and to identify which self-reported sleep alterations were associated with disability.

METHODS

Prospective exploratory study. Self-reported sleep alterations were measured by the Pittsburgh Sleep Quality Index, Insomnia Severity Index, Epworth Sleepiness Scale, and STOP-Bang Questionnaire. The dependent variable was measured 3 years after the first contact by the Modified Rankin Scale (mRS). Step-wise multiple linear regression analysis was employed to identify which sleep alterations were associated with disability.

RESULTS

Sixty-five individuals with stroke participated. About 67.7% of participants had poor sleep quality, 52.4% reported insomnia symptoms, 33.9% reported excessive daytime sleepiness, and 80.0% were classified as intermediate or high risk for obstructive sleep apnea. Only risk for obstructive sleep apnea was significantly associated with disability and explained 5% of the variance in the mRS scores.

CONCLUSION

Self-reported sleep alterations had a considerable frequency in a sample of chronic stroke individuals. The risk of obstructive sleep apnea was associated with disability in the chronic stage of stroke. Sleep alterations must be considered and evaluated in the rehabilitation process even after a long period since the stroke onset.

No Difference in Sleep Desaturations Severity between Patients with Wake-Up and Non-Wake-Up Stroke: A PRESS Study Results

BACKGROUND

Wake-up stroke (WUS) is a certain type of ischemic stroke in which a patient wakes up with a new neurological deficit due to cerebral ischemia. Sleep-disordered breathing is an independent risk factor for stroke, but the role of nocturnal oxygen desaturation in the pathophysiology of WUS is still insufficiently explored. According to several studies, patients with WUS have a significantly more severe sleep apnea syndrome and lower mean blood oxygen saturation. This study aimed to assess the severity of nocturnal desaturations in acute WUS and non-WUS patients using nocturnal pulse oximetry.

MATERIAL AND METHODS

The cohort of 225 consecutive patients with neuroimaging-verified acute cerebral ischemia was prospectively enrolled. For further analyses, 213 subjects with known WUS/non-WUS status were selected (111 males and 102 females, average age 70.4 ±12.9, median baseline NIHSS = 5, median baseline mRS = 3). Patients were divided into the WUS group (n = 45) and the non-WUS group (n = 168). Overnight pulse oximetry was performed within 7 days of the stroke onset and data of both of the studied groups were compared.

RESULTS

We found oxygen desaturation index (ODI) in the WUS group was 14.5 vs. 16.6 (p = 0.728) in the non-WUS group, basal O2 saturation was 92.2% vs. 92.5% (p = 0.475), average low O2 saturation was 90.3% vs. 89.6% (p = 0.375), minimal O2 saturation was 79.5% vs. 80.6% (p = 0.563), and time with O2 saturation <90% (T90) was 4.4% vs. 4.7% (p = 0.729).

CONCLUSIONS

In the studied sample, monitored respiratory parameters including ODI, basal O2 saturation, average low O2 saturation, minimal O2 saturation, and T90 did not significantly differ between groups of WUS and non-WUS patients.

Ethnic differences exist in sleepiness 3 Months after ischemic stroke

OBJECTIVE/BACKGROUND

To examine the association between ethnicity and 90-day post-stroke subjective sleepiness, an important determinant of quality of life, as measured by the Epworth Sleepiness Scale (ESS), among ischemic stroke survivors.

PATIENTS/METHODS

Mexican American (MA) and non-Hispanic white (NHW) recent ischemic stroke patients were identified from the population-based Brain Attack Surveillance in Corpus Christi Project (2010-2016). Subjects completed a baseline interview and 90-day outcome assessment that included the ESS. Excessive daytime sleepiness was defined as an ESS >10. Tobit regression models were used to assess associations between ethnicity and ESS unadjusted and adjusted for multiple potential confounders.

RESULTS

Among 1,181 (62.5% MA) subjects, mean ESS at 90 days was 8.9 (SD 6.0) among MA and 7.4 (SD 4.9) among NHW subjects: 1.45 (95% CI: 0.75, 2.15) points higher among MA than NHW subjects. After adjustment, mean ESS at 90 days was 1.16 (95% CI: 0.38, 1.94) points higher among MAs than NHWs. The prevalence of excessive daytime sleepiness was 39% among MA and 30% among NHW subjects (p = 0.0013).

CONCLUSIONS

Ninety days after stroke, sleepiness is worse in MAs compared to NHWs, even after accounting for potential confounding variables. Further studies should address ways to reduce this disparity.

[A long-term ischemic stroke risk score model in patients aged 60 years and older with obstructive sleep apnea: a multicenter prospective cohort study]

OBJECTIVE

To analyze the independent risk factors of long-term ischemic stroke and establish a nomogram for predicting the long-term risks in elderly patients with obstructive sleep apnea (OSA).

METHODS

This multicenter prospective cohort study was conducted from January, 2015 to October, 2017 among consecutive elderly patients (≥60 years) with newly diagnosed OSA without a history of cardio-cerebrovascular diseases and loss of important clinical indicators. The follow-up outcome was the occurrence of ischemic stroke. The baseline demographic and clinical data, sleep parameters, laboratory and ultrasound results were collected from all the patients, who were randomized into the modeling group (n=856) and validation group (n=258) at a 3∶1 ratio. LASSO regression was used for variable reduction and dimension screening, and the risk score prediction model of ischemic stroke was established based on Cox proportional hazard regression.

RESULTS

In the total of 1141 patients enrolled in this study, 58 (5.08%) patients experienced ischemic stroke during the median follow-up of 42 months (range 41-54 months). The cumulative incidence of ischemic stroke was 5.14% in the model group and 4.91% in the verification group (P < 0.05). Age (HR=3.44, 95% CI: 2.38- 7.77), fasting blood glucose (FPG) (HR=2.13, 95% CI: 1.22-3.72), internal diameter of the ascending aorta (HR=2.60, 95% CI: 1.0- 4.47), left atrial anteroposterior diameter (HR=1.98, 95% CI: 1.75-2.25) and minimum oxygen saturation (LSpO₂) (HR=1.57, 95% CI: 1.20-1.93) were identified as independent risk factors for ischemic stroke (P < 0.05 or 0.01). A long-term ischemic stroke risk score model was constructed based the regression coefficient ratios of these 5 risk variables. Before and after the application of the Bootstrap method, the AUC of the cohort risk score model was 0.84 (95% CI: 0.78- 0.90) and 0.85 (95% CI: 0.78- 0.89) in the model group and was 0.83 (95% CI: 0.73-0.93) and 0.82 (95%CI: 0.72-0.90) in the verification group, respectively, suggesting a good prediction efficiency and high robustness of the model. At the best clinical cutoff point, the cumulative incidence of ischemic stroke was significantly higher in the high-risk group than in the low-risk group (P=0.021).

CONCLUSION

This model can help to identify high-risk OSA patients for early interventions of the risks of ischemic stroke associated with OSA.