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.

Nusinersen treatment in adults with severe spinal muscular atrophy: A real-life retrospective observational cohort study

BACKGROUND AND OBJECTIVES

Spinal muscular atrophy (SMA) is a progressive neurodegenerative disease due to homozygous loss-of-function of the survival motor neuron gene SMN1 with absence of the functional SMN protein. Nusinersen, a costly intrathecally administered drug approved in 2017 in Europe, induces alternative splicing of the SMN2 gene, which then produces functional SMN protein, whose amount generally increases with the number of SMN2 gene copies.

METHODS

We retrospectively collected data from consecutive wheelchair-bound adults with SMA managed at a single center in 2018-2020. The following were collected at each injection, on days 1, 14, 28, 63, 183, and 303: 32-item Motor Function Measurement (MFM) total score and D2 and D3 subscores; the Canadian Occupational Performance Measure (COPM) performance and satisfaction scores; and lung function tests. The patients were divided into two groups based on whether their MFM total score was<or≥the mean (15.6%). Adverse events were recorded.

RESULTS

We identified 18 patients who received 4 to 8 Nusinersen injections. No significant improvements occurred over time in any of the MFM scores or lung function test results, which did not differ between groups. The COPM performance score improved significantly from day 0 to day 303 in the high-MFM group and the COPM satisfaction score in the overall population from D0 to D183. Half the patients achieved the minimal clinically important difference for both COPM scores.

DISCUSSION

The overall stability of conventional motor assessment in this population with advanced disabilities is encouraging to use more sensitive tools based on self-perception and autonomy in daily life activities, such as COPM. Our finding of a significant COPM performance score improvement from days 0 to 303 only in the patients with initial MFM-32 scores above the mean in the population suggests that the severity of the baseline disabilities may affect treatment efficacy.

CLASSIFICATION OF EVIDENCE LEVEL

IV, retrospective observational cohort study.

Respiratory rehabilitation in multiple sclerosis: A narrative review of rehabilitation techniques

BACKGROUND

Respiratory disorders in multiple sclerosis (MS) are an important issue. They can occur early during the course of the disease, are associated with the neurological impairment, and can lead to pneumonia and respiratory failure, which are the main causes of death in advanced MS. Prevailing impaired expiratory muscles and cough abilities has been demonstrated in this population and might constitute a specific target for rehabilitation interventions. However, international guidelines lack recommendations regarding respiratory rehabilitation in MS. Here we performed a systematic review of the published literature related to respiratory rehabilitation in MS.

METHODS

We searched the databases MEDLINE via PubMed, PEDro and Cochrane Library for English or French reports of clinical trials and well-designed cohorts published up to December 2016 with no restriction on start date by using the search terms "multiple sclerosis", "respiratory rehabilitation", "respiratory muscle training", "lung volume recruitment", "cough assistance", and "mechanical in-exsufflation". Literature reviews, case reports and physiological studies were excluded. The Maastricht criteria were used to assess the quality of clinical trials. We followed the Oxford Centre for Evidence-Based Medicine guidelines to determine level of evidence and grade of recommendations.

RESULTS

Among the 21 reports of studies initially selected, 11 were retained for review. Seven studies were randomized controlled trials (RCTs), 2 were non-RCTs, and 2 were observational studies. Respiratory muscle training (inspiratory and/or expiratory) by use of a portable resistive mouthpiece was the most frequently evaluated technique, with 2 level-1 RCTs. Another level-1 RCT evaluated deep-breathing exercises. All reviewed studies evaluated home-based rehabilitation programs and focused on spirometric outcomes. The disparities in outcome measures among published studies did not allow for a meta-analysis and cough assistance devices were not evaluated in this population.

CONCLUSION

Although respiratory muscle training can improve maximal respiratory pressure in MS and lung volume recruitment can slow the decline in vital capacity, evidence is lacking to recommend specific respiratory rehabilitation programs adapted to the level of disability induced by the disease.

[Diffuse interstitial pneumonitis with acute respiratory failure]

Drug-induced pneumonia due to ibuprofen is exceptional. We report the case of hypoxic interstitial pneumonitis with eosinophilic alveolitis induced by ibuprofen. The resolution was spontaneously obtained by the stop of this drug.

[Critical evaluation and predictive value of clinical presentation in out-patients with acute community-acquired pneumonia]

Diagnostic probability of community-acquired pneumonia (CAP) depends on data related to age and clinical and radiological findings. The critical evaluation of data in the literature leads to the following conclusions: 1) the prevalence of CAP in a given population with acute respiratory disease is 5% in outpatients and 10% in an emergency care unit. This could be as low as 2% in young people and even higher than 40% in hospitalized elderly patients; 2) the collection of clinical data is linked to the way the patient is examined and to the expertise of the clinician. The absolute lack of "vital signs" has a good negative predictive value in CAP; presence of unilateral crackles has a good positive predictive value; 3) there is a wide range of X-ray abnormalities: localized alveolar opacities; interstitial opacities, limited of diffused. The greatest radiological difficulties are encountered in old people with disorders including chronic respiratory or cardiac opacities and as a consequence of the high prevalence of bronchopneumonia episodes at this age; 4) among patients with lower respiratory tract (LRT) infections, the blood levels of leukocytes, CRP and procalcitonine are higher in CAP patients, mainly when their disease has a bacterial origin. Since you have not a threshold value reliably demonstrated in large populations with LRT infections or acute respiratory disease, presence or absence of these parameters could only be taken as a slight hint for a CAP diagnosis.

[Long term domiciliary mechanical ventilation in patients with neuromuscular disease (indications, establishment and follow up)]

Neuromuscular diseases represent a heterogeneous group of pathologies which common feature is the development of a restrictive ventilatory failure.

BACKGROUND

Respiratory insufficiency of neuromuscular origin manifests itself by functional symptoms that must be carefully searched for in the history, such as headaches, sleep disorders, or dyspnoea of effort, sometimes very mild, or in severe cases associated with orthopnoea. Follow up should be multi-disciplinary. On the respiratory level regular measurement of blood gases, vital capacity, maximum inspiratory and expiratory pressures as well as sleep studies, will detect the criteria for mechanical ventilation (hypercarbia > 45 mm Hg, nocturnal desaturation < 88%, vital capacity < 60%, PImax < 60 cm H2O).

STATE OF THE ART

The establishment of mechanical ventilation is a major decision for patients with neuromuscular disease because of the important physical, psychological, social and sometimes financial consequences. The patients and their family must be instructed precisely in order to obtain the best possible observation and compliance. The establishment requires a stay in hospital of several days to optimise the choice of ventilator, its settings, and connections. The link with the organisation managing the domiciliary ventilation is fundamental in ensuring follow up after discharge from hospital. Techniques of cough assistance must be taught to each neuromuscular patient requiring mechanical ventilation.

CONCLUSION

Ventilation of neuromuscular patients requires careful evaluation of the indications and rigorous follow up by a multidisciplinary team with wide experience of this type of disease.

Characteristics of tracheostomy phonation valves

Phonation valves are commonly used devices that allow the restoration of speech in tracheostomised patients. However, their use should not compromise the physiological benefit of tracheostomy. Six commercialised phonation valves were studied in a dynamic set-up simulating a respiratory frequency of 20 breaths.min(-1), a tidal volume of 0.5 L and a peak flow rate of 0.5 L.s(-1). Resistance and additional work of breathing (WOB) were calculated. In 10 tracheostomised patients, evaluations using no phonation valve (baseline), and the most and one of the least resistive valves were carried out. Respiratory patterns and gas exchanges were recorded. Inspiratory difficulty was evaluated using the modified Borg scale. Valves displayed a wide array of resistance ranging 1.3-5.9 cmH2O.L(-1).s(-1). Additional WOB varied with a ratio of 4.4 between the best and the worst valve. While the different clinical conditions did not modify respiratory patterns and gas exchanges, a significant effect on the Borg scale rating was observed using ANOVA and post hoc analysis of baseline versus worst valve and one of the best valves versus worst valve. In conclusion, the variety of aerodynamic characteristics of phonation valves should be considered when choosing the device, according to the underlying condition of the patients benefiting from their use.

Significance of phrenic nerve electrophysiological abnormalities in Guillain-Barre syndrome

The authors investigated whether the amplitude and latency of diaphragm compound muscle action potential helped predict respiratory failure in Guillain-Barré syndrome. Both variables were significantly but weakly correlated with vital capacity (VC) and were similar in unventilated (n = 60) and ventilated (n = 10) patients. In ventilated patients, motor loss severity, progression, and VC reduction were significantly greater, and bulbar dysfunction was more common. Predicting respiratory failure must rely on clinical features and VC.

[Optimising speech during artificial ventilation]

Speech is an essential component of quality of life for patients treated with long term mechanical ventilation. Therefore trying to improve phonation should always sought by physicians treating these patients. We review the different tools and techniques available in order to restore speech for patients with home mechanical ventilation whether ventilation is done continuously or not.

[Acute forms of diffuse interstitial hypoxemic pneumonia in immunocompetent patients]

The large majority of patients with acute respiratory failure present diffuse pulmonary opacities resulting from pulmonary embolism, intra-alveolar hemorrhage, or a classical cause of ARDS. In a small number of patients however, these opacities correspond to diffuse interstitial pneumonia. This should be suspected in light of the context, the time of formation, and the unusual respiratory and/or extrarespiratory signs. If there is a clinical doubt, thoracic scan and bronchoalveolar lavage should be performed together with infectious and immunology tests. Treatment depends on the cause and/or the type of lesion.

Spectrum of CD4 to CD8 T-cell ratios in lymphocytic alveolitis associated with methotrexate-induced pneumonitis

The present study was conducted to confirm the presence of severe lymphocytic alveolitis and to determine the factors responsible for the very different alveolar CD4 to CD8 T-cell ratios (CD4/ CD8) described in methotrexate-induced pneumonitis (MTX-pneumonitis). Clinical and radiologic findings, as well as bronchoalveolar lavage (BAL) data, including CD4 and CD8 subset analysis, were retrospectively reviewed for patients hospitalized between 1985 and 2000 for MTX-pneumonitis. BAL cell counts from patients with MTX-pneumonitis (cases) were compared with those from patients receiving MTX but who did not have evidence of MTX toxicity (MTX-exposed patients) and those from healthy subjects (control subjects). Nineteen BAL were performed in 14 consecutive cases of MTX-pneumonitis. MTX was given for various underlying diseases. All cases presented a subacute diffuse interstitial pneumonitis that recovered, with MTX discontinuation and/or initiation of adjunctive steroid therapy. At the time of diagnosis, BAL cell counts in MTX-pneumonitis indicated severe lymphocytic alveolitis when compared with MTX-exposed patients and control subjects and moderate neutrophil alveolitis compared with control subjects. The lymphocytic alveolitis resulted from an increase in both CD4 and CD8 lymphocyte cell counts. Nevertheless, alveolar CD4/ CD8 T-cell ratios ranged from 0.4 to 9.6. CD4/CD8 values correlated positively with lymphocyte counts but negatively with time elapsed between last MTX administration and BAL and with steroid cumulative dose received by the patients. Severe lymphocytic alveolitis was confirmed in our series of MTX-pneumonitis. The between-patient variation in CD4/CD8 T-cell ratios may reflect the large range of time intervals between last MTX administration and BAL evaluation and the use of adjunctive steroid therapy.

Evaluation of the biocompatibility of titanium-tantalum alloy versus titanium

To evaluate the biocompatibility of a new titanium-tantalum alloy, with qualities superior to titanium alone, for use in oral implantology, fibroblast and epithelial cell lines were grown on plastic, titanium, copper, and titanium-tantalum supports. Studies using scanning electron microscopy, flow cytometry, and cytotoxicity assays were conducted to compare the different supports. Scanning electron microscopic observations showed high densities of fibroblasts and epithelial cells with well-developed attachment systems in the form of cytoplasmic projections. Cell densities were lower on titanium and titanium-tantalum surfaces than on plastic. Cell numbers, as determined by cytotoxicity assays, were significantly higher on plastic than on titanium or titanium-tantalum surfaces while fibroblasts proliferated better than epithelial cells on both metal surfaces. Flow cytometric analyses of cell cycles did not reveal any significant variations in the distribution of cells among the cycle phases on the three materials. We found no differences with regard to the parameters studied between titanium and the titanium-tantalum alloy.