Background: Noninvasive ventilation (NIV) prolongs survival and quality of life in amyotrophic lateral sclerosis (ALS); however, its benefits depend upon the optimisation of both ventilation and adherence. We aimed to identify factors associated with effective initiation and ongoing use of NIV in ALS to develop evidence-based guidance and identify areas for further research.Methods: We searched 11 electronic databases (January 1998 to May 2018) for all types of quantitative and qualitative studies. Supplementary grey literature searches were conducted. Records were screened against eligibility criteria, data were extracted from included studies and risk of bias was assessed. We present findings using a narrative synthesis.Results: We screened 2430 unique records and included 52 quantitative and six qualitative papers. Factors reported to be associated with NIV optimisation included coordinated multidisciplinary care, place of initiation, selection of interfaces, ventilator modes and settings appropriate for the individual patient, and adequate secretion management. The literature indicated that patients with significant bulbar dysfunction can still derive considerable benefit from NIV if their needs are met. Research emphasises that obstructive airway events, mask leak and uncontrolled secretions should be addressed by adjustments to the interface and machine settings, and the concomitant use of cough augmentation.Conclusion: This review highlights that NIV optimisation requires an individualised approach to respiratory management tailored to the differing needs of each patient. Ultimately, this should lead to improved survival and quality of life. This review expands on recommendations in current international guidelines for NIV use in ALS and identifies areas for future research.

We present the case of a patient with multiple system atrophy who presented with central apnea as the only sleep disordered breathing, associated with REM behavior disorder and restless legs syndrome. This presentation of the disease is unusual and probably reflects more widespread involvement at the onset. With this case, we show the importance of considering this kind of disease in the differential diagnosis of central sleep apnea syndromes.

Rationale: Obstructive sleep apnea (OSA) is associated with impaired glycemic control and a higher risk of vascular complications, such as diabetic retinopathy. However, the effect of apnea–hypopnea suppression on retinal disease progression is unclear. Objectives: To evaluate the efficacy and safety of continuous positive airway pressure (CPAP) for the reduction of retinal lesions in patients with non-proliferative diabetic retinopathy (NPDR) and OSA. Methods: This open-label, parallel-group, randomized controlled trial was conducted between October 2016 and February 2020 at a university hospital in Spain. The date of final follow-up was March 2, 2021. Eighty-three patients with OSA and mild to moderate NPDR receiving stable treatment were randomized to receive CPAP and usual care (43 patients with 79 available eyes) or usual care alone (40 patients with 67 available eyes) for 52 weeks. The primary outcomes were the change in the percentage of eyes with retinal exudates and the number of retinal microhemorrhages from baseline to week 52. We also assessed the effects of both interventions on retinal thickness by means of optical coherence tomography, serum concentrations of glycated hemoglobin, blood pressure, lipid concentrations, sleepiness, and quality of life. Results: Fifty-two weeks of CPAP treatment was associated with reductions from baseline in the percentage of eyes with hard exudates (overall difference, −21.7%; P = 0.035) and in optical coherence tomography indices of retinal edema, including central subfield thickness and cube volume. However, in patients who met prespecified criteria for CPAP adherence, treatment was also associated with a higher number of retinal microhemorrhages at 52 weeks (intergroup adjusted difference, 6.0 [95% confidence interval, 0.6–11.5]; P = 0.029), which was directly related to prescribed pressure levels. CPAP treatment also improved glycemic control, sleepiness, and general health-related quality of life. Conclusions: In patients with OSA and NPDR, long-term CPAP treatment in addition to usual care may result in slower progression of retinal disease, although it could also induce an increase in retinal microhemorrhages. Clinical trial registered with www.clinicaltrials.gov (NCT02874313).

Obstructive sleep apnea (OSA) patients are at special risk of suffering atherosclerosis, leading to major cardiovascular diseases. Notably, the transforming growth factor (TGF-β) plays a crucial role in the development and progression of atherosclerosis. In this context, the central regulator of TGF-β pathway, SMAD4 (small mother against decapentaplegic homolog 4), has been previously reported to be augmented in OSA patients, which levels were even higher in patients with concomitant cardiometabolic diseases. Here, we analyzed soluble and intracellular SMAD4 levels in plasma and monocytes from OSA patients and non-apneic subjects, with or without early subclinical atherosclerosis (eSA). In addition, we used in vitro and ex vivo models to explore the mechanisms underlying SMAD4 upregulation and release. Our study confirmed elevated sSMAD4 levels in OSA patients and identified that its levels were even higher in those OSA patients with eSA. Moreover, we demonstrated that SMAD4 is overexpressed in OSA monocytes and that intermittent hypoxia contributes to SMAD4 upregulation and release in a process mediated by NLRP3. In conclusion, this study highlights the potential role of sSMAD4 as a biomarker for atherosclerosis risk in OSA patients and provides new insights into the mechanisms underlying its upregulation and release to the extracellular space.