High-flow nasal cannula ventilation therapy for obstructive sleep apnea in ischemic stroke patients requiring nasogastric tube feeding: a preliminary study.

Obstructive sleep apnea (OSA) is associated with increasing risk of recurrent stroke and mortality. Nasogastric tubes used by dysphagic stroke patients may interfere with nasal continuous positive airway pressure (CPAP) due to air leakage. This study was evaluated the effects and short-term tolerability of high-flow nasal cannula (HFNC) therapy for OSA in stroke patients with nasogastric intubation. The HFNC titration study was performed in post-acute ischemic stroke patients with nasogastric intubation and OSA. Then, participants were treated with HFNC therapy in the ward for one week. Eleven participants (eight males) who were all elderly with a median age of 72 (IQR 67-82) years and a body mass index of 23.5 (IQR 22.0-26.6) completed the titration study. The HFNC therapy at a flow rate up to 50~60 L/min significantly decreased the apnea-hypopnea index from 52.0 events/h (IQR 29.9-61.9) to 26.5 events/h (IQR 3.3-34.6) and the total arousal index from 34.6 (IQR 18.6-42.3) to 15.0 (IQR 10.3-25.4). The oxygen desaturation index was also significantly decreased from 53.0 events/h (IQR 37.0-72.8) to 16.2 events/h (IQR 0.8-20.1), accompanied by a significant improvement in the minimum SpO2 level. Finally, only three participants tolerated flow rates of 50~60 L/minute in one-week treatment period. Conclusively, HFNC therapy at therapeutic flow rate is effective at reducing the OSA severity in post-acute ischemic stroke patients with nasogastric intubation. Owing to the suboptimal acceptance, HFNC might be a temporary treatment option, and CPAP therapy is suggested after the nasogastric tube is removed.

Poststroke Depressive Symptoms Are Associated With Increased Oxidative Deoxyribonucleic Acid Damage.

Poststroke depression is independently associated with poor health outcomes, such as increased mortality, disability, anxiety, and lower quality of life. Identifying the potential biomarkers and detailed mechanisms of poststroke depression may improve the effectiveness of therapeutic intervention. In this cross-sectional study, the authors recruited patients with subacute ischemic stroke who were consecutively admitted for neurorehabilitation. Depression was assessed with the Patient Health Questionnaire-9 (PHQ-9), with a cutoff based on a summed-items score of 10. Polysomnography and laboratory tests for oxidative stress and inflammation were arranged. In total, 139 patients (97 men [69.8%] and 42 women [30.2%]; mean age: 63.2 years [±13.4]) with recent ischemic stroke were recruited and divided into two groups based on their depressive symptoms. Body mass index (BMI), the Barthel Index, percentage of antidepressant usage, and percentage of rapid eye movement (REM) sleep differed significantly between the two groups. The PHQ-9 score was significantly correlated with the levels of total antioxidant capacity, C-reactive protein, and urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG). Urinary 8-OHdG, a marker of oxidative stress to DNA, remained significantly and positively correlated with PHQ-9 scores after adjusting for BMI, sleep-onset latency, Barthel Index, mean oxyhemoglobin saturation, age, antidepressant usage, and percentage of REM sleep by using multivariate linear regression. Depressive symptoms were related to increased oxidative DNA damage in patients with subacute ischemic stroke. Urinary 8-OHdG may serve as a potential biomarker for poststroke depression. Further longitudinal studies are needed to elucidate the causal relationship between poststroke depression and elevated oxidative stress level.

Nocturnal Desaturation is Associated With Atrial Fibrillation in Patients With Ischemic Stroke and Obstructive Sleep Apnea.

STUDY OBJECTIVES: Both atrial fibrillation (AF) and obstructive sleep apnea (OSA) are risk factors for ischemic stroke. Previous studies suggested that OSA is associated with AF in individuals who have not had a stroke. For better secondary prevention of stroke, this study determined the association between OSA and AF among patients with ischemic stroke. METHODS: This cross-sectional study recruited consecutive patients with subacute ischemic stroke admitted for neurorehabilitation. The baseline and clinical data were collected, and standard polysomnography was performed in a sleep center. RESULTS: The 47 women and 111 men enrolled in this study were divided into two groups according to the presence of AF. The AF group (n = 26) had a significantly older age (72.2 versus 60.1 years, P = .016), significantly more disability (Barthel index: 35 versus 45, P = .045), and marginally higher mean oxygen desaturation (6.7% versus 5.6%, P = .079) compared to the non-AF group. The two groups did not significantly differ in sex, body mass index, prevalence of hyperthyroidism, and other parameters of OSA. The multivariate logistic regression analysis revealed that mean desaturation was significantly associated with AF after adjusting for age, neck circumference, Barthel index and high-density lipoprotein level (odds ratio = 1.19 (95% confidence interval 1.05-1.35), P = .008). CONCLUSIONS: Nocturnal hypoxia due to OSA is an independent predictor of AF in patients with subacute ischemic stroke. The use of overnight pulse oximeter to assess nocturnal hypoxia and predict paroxysmal AF in patients with cryptogenic stroke needs further evaluation. COMMENTARY: A commentary on this article appears in this issue on page 667.

Association of inflammation and oxidative stress with obstructive sleep apnea in ischemic stroke patients.

OBJECTIVE: The role of obstructive sleep apnea (OSA) in the mortality and further cardiovascular risk in subjects with ischemic stroke remains a contentious issue. Oxidative stress and inflammatory reaction due to OSA have seldom been studied in stable ischemic stroke patients. PATIENTS/METHODS: This cross-sectional, prospective study involved 92 consecutive ischemic stroke patients who were admitted to the Rehabilitation ward. All subjects received polysomnography and laboratory tests for oxidative stress and inflammatory biomarkers, including: C-reactive protein (CRP), interleukin 6 (IL-6), total antioxidant capacity (TAC), and urinary 8-hydroxy-2-deoxyguanosine. Differences in study variables between patients with or without severe OSA were compared, and multivariate linear regression analyses were used to assess the relationship between OSA severity and target biomarkers. RESULTS: Participants in the severe OSA group were significantly older (p = 0.002), had a significantly higher risk of hypertension (p = 0.021) and a lower level of CRP (p = 0.006). Among the subjects with ischemic stroke and severe OSA, the levels of CRP, IL-6, and TAC were positively correlated with the desaturation index (DI) and the TAC levels were negatively correlated with mean arterial oxygen saturation (SaO2). Regression analysis results indicated that the TAC levels remained significantly and negatively correlated with mean SaO2 levels. Moreover, the CRP levels remained significantly correlated with the apnea-hypopnea index and DI after controlling for covariates. CONCLUSIONS: The present study demonstrated that a preferentially adaptive antioxidative response to hypoxia emerges, and the role of OSA with respect to inflammatory reaction is attenuated, in ischemic stroke patients with OSA.

Bortezomib-induced posterior reversible encephalopathy syndrome: clinical and imaging features.

Posterior reversible encephalopathy syndrome (PRES) is a rare and potentially harmful complication in patients receiving targeted chemotherapy. We herein present a case of PRES that occurred after 33 days of high-dose bortezomib treatment and propose both overwhelmed cerebral autoregulation and toxin-mediated blood-brain barrier damage as the underlying mechanisms based on the imaging findings. A favorable recovery was observed two days after achieving stringent hypertension control and withholding bortezomib. Follow-up images obtained two weeks later unveiled a dramatic remission, with faint areas of subcortical hyperintensity in the bilateral parieto-occipital regions. With explicit clinical and imaging features, this case highlights the need for early recognition of PRES during the clinical course of bortezomib therapy.