Predictive factors and screening strategy for obstructive sleep apnea in patients with advanced multiple sclerosis

BACKGROUND

Obstructive sleep apnea (OSA) screening questionnaires have been evaluated in Multiple Sclerosis (MS) but not yet validated in patients with advanced disease. The aim of this study is to identify OSA predictive factors in advanced MS and to discuss screening strategies.

METHODS

Oximetry data from 125 patients were retrospectively derived from polysomnographic reports. Univariate and multivariate analysis were used to determine predictive factors for OSA. A two-level screening model was assessed combining the oxygen desaturation index (ODI) and a method of visual analysis.

RESULTS

multivariate analysis showed that among the clinical factors only age and snoring were associated with OSA. Usual predictive factors such as sleepiness, Body mass index (BMI) or sex were not significantly associated with increased Apnea Hypopnea Index (AHI). The ODI was highly predictive (p < 0.0001) and correctly identified 84.1 % of patients with moderate OSA and 93.8 % with severe OSA. The visual analysis model combined with the ODI did not outperform the properties of ODI used alone.

CONCLUSION

As the usual clinical predictors are not associated with OSA in patients with advanced MS, questionnaires developed for the general population are not appropriate in these patients. Nocturnal oximetry seems a pertinent, ambulatory and accessible method for OSA screening in this population.

Nasal versus oronasal masks for home non-invasive ventilation in patients with chronic hypercapnia: a systematic review and individual participant data meta-analysis

BACKGROUND

The optimal interface for the delivery of home non-invasive ventilation (NIV) to treat chronic respiratory failure has not yet been determined. The aim of this individual participant data (IPD) meta-analysis was to compare the effect of nasal and oronasal masks on treatment efficacy and adherence in patients with COPD and obesity hypoventilation syndrome (OHS).

METHODS

We searched Medline and Cochrane Central Register of Controlled Trials for prospective randomised controlled trials (RCTs) of at least 1 month's duration, published between January 1994 and April 2019, that assessed NIV efficacy in patients with OHS and COPD. The main outcomes were diurnal PaCO₂, PaO₂ and NIV adherence (PROSPERO CRD42019132398).

FINDINGS

Of 1576 articles identified, 34 RCTs met the inclusion criteria and IPD were obtained for 18. Ten RCTs were excluded because only one type of mask was used, or mask data were missing. Data from 8 RCTs, including 290 IPD, underwent meta-analysis. Oronasal masks were used in 86% of cases. There were no differences between oronasal and nasal masks for PaCO₂ (0.61 mm Hg (95% CI -2.15 to 3.38); p=0.68), PaO₂ (-0.00 mm Hg (95% CI -4.59 to 4.58); p=1) or NIV adherence (0·29 hour/day (95% CI -0.74 to 1.32); p=0.58). There was no interaction between the underlying pathology and the effect of mask type on any outcome.

INTERPRETATION

Oronasal masks are the most used interface for the delivery of home NIV in patients with OHS and COPD; however, there is no difference in the efficacy or tolerance of oronasal or nasal masks.

Expiratory obstruction in patients with Duchenne muscular dystrophy under non-invasive ventilation: A step-by-step analysis of a new obstructive pattern

PURPOSE

Non-invasive ventilation (NIV) is the reference standard for managing chronic hypoventilation in patients with Duchenne muscular dystrophy (DMD). In these patients, upper airway obstruction under NIV may compromise efficacy and adherence. We aim to describe a novel pattern of expiratory obstructive events occurring during nocturnal barometric NIV.

METHODS

We retrospectively included all patients with DMD who underwent full-night polygraphy during NIV as part of their usual follow-up between May 2018 and July 2019.

RESULTS

We provide a step-by-step description of this previously undescribed pattern of obstruction. Expiratory obstructions lead to end-inspiratory breath-holding and impossibility to take another inspiratory breath with a barometric mode until expiration occurs. These events were observed in 4 (36%) of 11 DMD patients under barometric NIV.

CONCLUSION

Expiratory obstructions may be common in DMD patients receiving NIV and should be sought out routinely. This previously undescribed variant of obstructive event must be identified.

Impact of Interface Type on Noninvasive Ventilation Efficacy in Patients With Neuromuscular Disease: A Randomized Cross-Over Trial

BACKGROUND AND OBJECTIVE

Around 25% of patients with neuro-muscular diseases (NMD) are treated by home noninvasive ventilation (NIV) through an oronasal mask. However, there is growing evidence that nasal masks require lower NIV pressures and result in fewer residual obstructive events. We hypothesized that nasal masks would improve efficacy and reduce side effects compared to oronasal masks in this population.

METHODS

open label, cross-over, randomized, study in 2 tertiary care hospitals. Patients with NMD treated by home NIV were randomized for one-week periods to nasal and oronasal interfaces respectively (cross-over). At the end of each period, nocturnal polygraphy (monitoring mouth opening) under NIV, synchronized with transcutaneous partial pressure in CO₂ (tcCO₂) was performed. Data were collected from the NIV built-in software and NIV side-effects were collected. Intention-to-treat and per protocol analyses were performed. The primary outcome was mean nocturnal SpO₂. The secondary outcomes were: percentage of sleep with SpO₂<90%, oxygen desaturation index (ODI), mean tcCO₂, mean duration of mouth opening during sleep, level of non-intentional leaks and side-effects.

RESULTS

Thirty patients with NMD were included. There were no between-group differences for either the primary or secondary outcomes. Post hoc comparisons showed that changing between interfaces reduced NIV efficacy: mean nocturnal SpO₂ (p=0.04), ODI (p=0.01), mean tcCO2 (p=0.048), side-effects (p=0.008).

CONCLUSION

Nasal masks did not improve NIV efficacy or reduce side effects compared to oronasal masks in patients with NMD treated by home NIV. The efficacy of NIV is reduced during the transition to another interface, requiring close monitoring. Registration number: NCT03458507.

Adherence to CPAP with a nasal mask combined with mandibular advancement device versus an oronasal mask: a randomized crossover trial

PURPOSE

Evidence for the management of CPAP-treated obstructive sleep apnea suggests that oronasal masks reduce mouth leaks at the expense of higher pressures and poorer adherence. Some authors have proposed the use of mandibular advancement devices in combination with nasal masks to address this. The aim of this study was to assess adherence to CPAP after 1 month's use of a nasal mask with a mandibular advancement device and to compare adherence with an oronasal mask.

METHODS

A randomized crossover trial design to assess whether a mandibular advancement device combined with a nasal mask would improve CPAP adherence compared to an oronasal mask.

RESULTS

There was no improvement in CPAP adherence and self-reported interface-related pain was significantly higher with the combined treatment.

CONCLUSIONS

Although the combined treatment reduced pressures, likely by improving upper airway patency, it may only be appropriate for a small number of patients due to associated discomfort.

TRIAL REGISTRATION

NCT01889472.

IV steroids during long episodes of Kleine-Levin syndrome

OBJECTIVE

To retrospectively compare the benefits (episode cessation) and risks of IV methylprednisolone (IV-MP) vs abstention during prolonged Kleine-Levin syndrome (KLS) episodes.

METHODS

A total of 26 patients with KLS received 1 g/d IV-MP for 3 days during 1 to 6 episodes each (totaling 43 IV-MP sessions). The change of episode duration with IV-MP (vs previous episode duration) was compared with the change duration between 2 consecutive episodes in 48 untreated patients matched for age, sex, age at KLS onset, number of episodes, and disease duration (more treated than untreated patients had long episodes).

RESULTS

Eleven patients (42.3%) had an episode that was at least 1 week shorter than the preceding one when they received IV-MP therapy, whereas shorter episodes were significantly less frequent (10.4%) in the untreated group. This benefit was more marked (65.5% responders, 12 fewer days in an episode vs 0 days in the untreated patients) when IV-MP was infused before the 10th day of the episode. Mild, transient adverse effects (insomnia, muscle pain, nervousness/restlessness, but no manic switching) were reported by 61.3% of patients. No specific responder profile was identified.

CONCLUSION

In this open-labeled, naturalistic study, early IV-MP (following the protocol for multiple sclerosis relapses) had a good benefit/risk ratio during KLS episodes in patients with long episodes (with half of the patients having an early cessation of episodes).

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that for patients with long episodes of KLS, IV steroids decrease the duration of KLS episodes.

Diagnosis, follow-up and management of sleep-disordered breathing in children with osteogenesis imperfecta

OBJECTIVES

Osteogenesis imperfecta (OI) is the most common genetic skeletal disorder. Extraskeletal findings are common but an association with sleep-disordered breathing (SDB) has never been described. The aim of this study was to investigate clinical features of children with OI and suspected SDB.

METHODS

A retrospective study of clinical records, signs of SDB and polysomnographic recordings of children with OI was performed. We paid particular attention to symptoms that could be associated with SDB in this population - scoliosis, kyphosis, vertebral arthrodesis, chest wall deformities, basilar impression, autonomy - as well as data already known to be associated with obstructive sleep apnea such as body mass index and upper-airway impairment.

RESULTS

We reviewed the clinical charts of 188 patients referred to our genetic skeletal disorders reference center for OI. Among the 15 patients (8%) with polysomnographic recordings, 12 (6.4%) had sleep-disordered breathing. We found a negative correlation between the Brief Assessment of Motor Function score and Apnea Hypopnea Index (r=-0.68; p=0.01) and Desaturation Index (r=-0.62; p=0.02). The Apnea Hypopnea Index was higher for non-walkers than walkers (mean [SD]: 6.5 [3.6] vs. 2.4 [1.5]; p=0.02) and with type III versus IV OI. Two patients were started on continuous positive airway pressure ventilation, with clinical improvement.

CONCLUSION

For OI children, symptoms suggesting obstructive sleep disorders should be searched for systematically, especially in children with compromised autonomy, high body mass index, trunk deformations, and severe OI type.

Role of nitric oxide in the anti-tumoral effect of retinoic acid and 1,25-dihydroxyvitamin D3 on human promonocytic leukemic cells

All trans retinoic acid and vitamin D3 derivatives are well known for their antileukemic activity, while the precise mechanism of this effect remains to be clarified. Using human leukemic U937 and THP-1 promonocytic cell lines, we analyzed the effect of all-trans retinoic acid (RA) and/or 1,25-dihydroxyvitamin D3 (VD) on the generation of nitric oxide (NO), a potent antitumoral mediator. U937 cell differentiation with VD or with both RA and VD (RA/VD) correlated with gene transcription and functional expression of inducible nitric oxide synthase (iNOS). Nitrites and L-citrulline were also detected in U937 cell supernatants as soon as 24 hours following cell incubation with VD or RA/VD, but not in cells treated with RA alone. Inhibition of iNOS activity by NG-monomethyl-L-arginine (LNMMA) significantly decreased in vitro U937 cell differentiation with VD and RA/VD as shown by the expression of cell differentiation markers (CD14 and CD68) and by the capacity of these cells to undergo a luminol-dependent chemiluminescence in response to opsonized zymosan. Similar results were obtained using the THP-1 cell line strengthening the role of NO in the VD- and RA/VD-induced growth arrest and terminal differentiation of promonocytic leukemia cells.