Factors Associated With Change in S3-NIV Score Over Time in People With Chronic Respiratory Failure Treated With Long-Term Home Noninvasive Ventilation.

INTRODUCTION: Monitoring changes in symptoms over time during long-term nocturnal home non-invasive ventilation (NIV) using patient-reported outcome measures is crucial. This study aimed to identify factors associated with changes in the S3-NIV total score, its two domains ("respiratory symptoms" and "sleep and NIV-related side effects") and individual item responses. METHODS: We conducted a retrospective, longitudinal data analysis of a cohort of adults with chronic respiratory failure treated with NIV. Data were obtained from a French homecare provider. Multivariate linear and multinomial ordinal mixed effect models were used to identify factors associated with changes in S3-NIV scores over time. RESULTS: Median follow-up was 2 years for 2135 participants. Each participant completed a median of five S3-NIV questionnaires; totaling 11,359 analyzed questionnaires. Type of respiratory condition, sex, age and time since NIV initiation were associated with change in S3-NIV score over time. NIV adherence was not associated with total S3-NIV score but high adherence was associated with more severe respiratory symptoms and an improvement in sleep and NIV-related side effects during the follow-up. Intensity of pressure support was associated with a lower total S3-NIV score and more side effects. Face masks and supplemental oxygen were associated with a lower S3-NIV total score. CONCLUSION: Changes in S3-NIV scores over time are associated with the individual's characteristics and NIV settings. Analysis of the two domains and individual items of the S3-NIV could increase understanding of the difficulties experienced by people on NIV.

Feasibility of home initiation of an airway clearance device (SIMEOX) by telecare in people with non-cystic fibrosis bronchiectasis: a pilot study.

BACKGROUND: Mucociliary clearance is a cornerstone of the management of people with non-cystic fibrosis bronchiectasis (NCFB). SIMEOX, an innovative device, could facilitate autonomous airway clearance, but its use requires specific training. We hypothesised that telecare would be an effective means to train people with NCFB in the handling of device and to monitor and promote device adherence. OBJECTIVES: (1) To evaluate frequency of use of the SIMEOX for 10 weeks after telecare training. (2) To assess user satisfaction and clinical efficacy of the SIMEOX+telecare. METHODS: Multicentre, prospective, pilot study in adults with NCFB. A SIMEOX was provided to each participant at inclusion. Physiotherapists performed telecare sessions the first 2 weeks (3-5 sessions) for device training and every 10 days to reinforce motivation and provide technical support. RESULTS: 22 individuals were included, 21 analysed (38% male; mean±SD age 53±18 years; Bronchiectasis Severity Index 6.6±3.5). Fourteen participants (66.7%; 95% CI 43.1% to 84.5%) performed ≥3 SIMEOX sessions/week (self-reported adherence, primary outcome). Median (Q1; Q3) number of self-reported sessions/week for the whole group was 3.7 (1.8; 5.7). Adherence including web registration was 80.9%. At week 12, participant satisfaction rating was 9.0 (7.9; 10.0) on a 10-point visual analogue scale; respiratory function did not change but quality of life improved (COPD Assessment Test score -4.7, 95% CI -7.7 to -1.6, p=0.023; St Georges Respiratory Questionnaire -5.8, 95% CI -10.8 to -0.9, p=0.005). CONCLUSION: Adherence to and satisfaction with the SIMEOX airway clearance device supported by telecare were high in people with NCFB. The clinical efficacy needs to be confirmed in a randomised controlled trial. TRIAL REGISTRATION NUMBER: NCT04742270.

High prevalence with no gender difference of likely eating disorders in type 1 mellitus diabetes on insulin pump.

AIM: The aim of this study was to determine the prevalence of likely eating disorders and insulin misuse in a prospective cohort of adults with type 1 diabetes mellitus (T1DM) treated with insulin pump therapy. METHODS: This prospective study was held at the participants' home. The participants completed the SCOFF questionnaire as well as a question related to insulin misuse. Information about lifestyle, medical history, insulin pump and Continuous Glucose Monitoring (CGM) data were collected. RESULTS: The analysis covered 198 participants with a median age of 51 [95% CI 38; 62] years. The prevalence of likely eating disorders was 21.7% (95% CI 16.3; 28.2) in the study population and 20.6% (95% CI 14.3; 28.6) and 24.2% (95% CI 14.6; 37.0) in males and females respectively. The prevalence of insulin misuse was 39.0% (95% CI 30.8; 47.7). There was no significant difference in prevalence between males and females for likely eating disorders and insulin misuse. The analysis of CGM data revealed no factors related to glycaemic control associated with likely eating disorders. CONCLUSION: The results of this study indicate that the prevalence of likely eating disorders is high even in a middle-aged population with a T1DM and satisfactory glucose control.

Peer-driven intervention to help patients resume CPAP therapy following discontinuation: a multicentre, randomised clinical trial with patient involvement.

INTRODUCTION: Obstructive sleep apnoea syndrome (OSAS) is one of the most common chronic diseases. It may be associated with symptoms of excessive daytime sleepiness and neurocognitive and cardiovascular complications. First line therapy for OSAS involves home continuous positive airway pressure (CPAP), however, nearly half of patients do not adhere with this treatment over the long term. Cognitive-behavioural interventions that include health professionals and patient and public involvement are increasingly advocated in the fields of education and research. We hypothesise that a peer-driven intervention could help patients with OSAS to resume CPAP use after discontinuation. METHODS AND ANALYSIS: We have designed a prospective, multicentre randomised, controlled trial that will be coconducted by health professionals, a home provider of CPAP and patients as experts or peers or participants. The primary aim is to evaluate the impact of a 6-month, peer-driven intervention to promote the resumption of CPAP after discontinuation. We anticipate that 20% of patients in the intervention group will reuse CPAP as compared with 6% in control group, thus, 104 patients must be included in each group. The secondary aims are (1) to evaluate the impact of the peer-driven intervention on adherence to CPAP compared with the control group (mean adherence and percentage of nights with at least 4 hours' use/night for 70% of nights); (2) to determine factors associated with resumption of CPAP; (3) to assess patient satisfaction with the peer-driven intervention at 6 months; (4) to evaluate the feasibility and the execution of the peer-driven intervention and peer satisfaction. Adult outpatients with an established diagnosis of severe OSA (Apnoea-Hypopnoea Index >30 events/hour) that have stopped using CPAP within 4-12 months after initiation will be recruited. The peers who will perform the intervention will be patients with OSAS treated with CPAP with good adherence (at least 4 hours/night, 70% of nights) and trained in motivational enhancement and cognitive-behavioural therapies. Trained peers will conduct three interviews within 6 months with participants. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the French Regional Ethics Committee CPP Ouest II-Angers, (IRB 21.02.25.68606 (2021/2025)). All participants will sign written informed consent. The results will be presented at conferences and published in peer-reviewed journals as well as public media. TRIAL REGISTRATION NUMBER: NCT04538274.

Energy conservation technique improves dyspnoea when patients with severe COPD climb stairs: a randomised crossover study.

In this randomised, crossover trial, 22 patients with severe chronic obstructive pulmonary disease climbed six flights of stairs (108 steps) twice, under two test conditions: (1) energy conservation technique (ECT): participants were asked to rest for at least 5 seconds every three steps and (2) control condition: participants climbed the stairs at their own pace. Significant lower dyspnoea (primary outcome), leg discomfort, minute ventilation and capillary blood lactate under the ECT condition were found, with no change in total task time. CLINICAL TRIAL REGISTRATION: NCT03564028.

Validation of an apnea and hypopnea detection algorithm implemented in implantable cardioverter defibrillators. The AIRLESS study.

Diagnosis of sleep apnea (SA) using simple tools has the potential to improve the efficacy of cardiac implants in the prevention of cardiac arrhythmias. The aim of the present study was to validate a transthoracic impedance sensor for SA diagnosis in patients with cardiac implants. We compared the apnea-hypopnea index (AHI) obtained from polysomnography (AHIPSG) with the AHI obtained from autoscoring algorithms of the ApneaScan implantable impedance respiration sensor (AHIAS) three months after implantation of cardioverter-defibrillator (ICD) or cardiac resynchronization therapy-defibrillator (CRT-D) devices. Twenty-five patients with indications for implantation of ICD or CRT-D (INCEPTA; Boston Scientific) (24 men, 59.9 ± 14.4 years; LVEF 30.3 ± 6.4%; body mass index 25.9 ± 4.2 kg/m²) were included. Mean AHI-PSG was 21.9 ± 19.1 events/hr. A significant correlation was found between AHIPSG and AHIAS especially for the most severe SA (Spearman correlation: 0.71, p < 0.001). Intraclass Correlation Coefficient (was in the expected range: 0.67, 95% CI: 0.39-0.84. The mean bias was 5.4 events per hour (mean AHI: 23.3 ± 14.6 versus 29.7 ± 13.7 for AHI-PSG and AHI-AS, respectively). An optimal cutoff value for the AHIAS at 30 events/h was obtained from the Receiver Operator Characteristic (ROC) curve analysis, which yielded a sensitivity of 100%, a specificity of 80%, PPV = 67%, NPV = 100%. Using an advanced algorithm for autoscoring of transthoracic impedance included in ICDs is reliable to identify SA and has the potential to improve the management of patients with cardiac implants.

Cysteinyl-leukotriene pathway as a new therapeutic target for the treatment of atherosclerosis related to obstructive sleep apnea syndrome.

AIMS: Obstructive sleep apnea (OSA) characterized by nocturnal intermittent hypoxia (IH) is associated with atherosclerosis and cysteinyl-leukotrienes (CysLT) pathway activation. We aimed to identify the determinants of CysLT pathway activation and the role of CysLT in OSA-related atherosclerosis. METHODS AND RESULTS: Determinants of the urinary excretion of LTE4 (U-LTE4) including history of cardiovascular events, polysomnographic and biological parameters were studied in a cohort of 170 OSA patients and 29 controls, and in a subgroup of OSA patients free of cardiovascular event (n = 136). Mechanisms linking IH, the CysLT pathway and atherogenesis were investigated in Apolipoprotein E deficient (ApoE-/-) mice exposed to 8-week IH. In the whole cohort, U-LTE4 was independently influenced by age, minimal oxygen saturation, and a history of cardiovascular events, and correlated significantly with intima-media thickness. In the subgroup of OSA patients free of cardiovascular event, increased U-LTE4 was increased compared to controls and independently related to hypoxia severity and traditional risk factors aggregated in the 10-year cardiovascular risk score of European Society of Cardiology. In IH mice, atherosclerosis lesion size and mRNA levels of 5-lipoxygenase, 5-lipoxygenase activating protein (FLAP) and CysLT1 receptor were significantly increased. This transcriptional activation was associated with the binding of HIF-1 to the FLAP promoter and was strongly associated with atherosclerosis lesion size. CysLT1 receptor antagonism (montelukast) significantly reduced atherosclerosis progression in IH mice. CONCLUSIONS: IH-related CysLT pathway activation contributes to OSA-induced atherogenesis. In the era of personalized medicine, U-LTE4 may be a useful biomarker to identify OSA patients for whom CysLT1 blockade could represent a new therapeutic avenue for reducing cardiovascular risk.

Nasal Obstruction Symptom Evaluation Score to Guide Mask Selection in CPAP-Treated Obstructive Sleep Apnea.

Nasal obstruction is frequently reported by patients with sleep apnea and complicates the choice of a nasal or oronasal mask for continuous positive airway pressure (CPAP) therapy. However, the type of interface used for the delivery of CPAP is crucial to ensure tolerance and compliance. The aim of this prospective pilot study was to identify whether the validated Nasal Obstruction Symptom Evaluation (NOSE) score rated at CPAP initiation was associated with the type of mask used after 4 months of treatment. Patients completed the NOSE questionnaire before initiation with automatic CPAP. The mask used (nasal/oronasal) after 4 months was documented. In total, 198 consecutive patients with sleep apnea were included. NOSE score (>50/100) was independently associated with the use of an oronasal mask at 4 months (sensitivity, 34.8%; specificity, 87.5%). The NOSE questionnaire could be a simple decision-making tool to guide the choice of mask during CPAP initiation.

Determinants of Unintentional Leaks During CPAP Treatment in OSA.

BACKGROUND: Unintentional leakage from the mouth or around the mask may lead to cessation of CPAP treatment; however, the causes of unintentional leaks are poorly understood. The objectives of this study were (1) to identify determining factors of unintentional leakage and (2) to determine the effect of the type of mask (nasal/oronasal) used on unintentional leakage. METHODS: Seventy-four polysomnograms from patients with OSA syndrome treated with auto-CPAP were analyzed (23 women; 56 ± 13 years; BMI, 32.9 kg/m2 (range, 29.0-38.0 kg/m2). Polysomnographic recordings were obtained under auto-CPAP, and mandibular behavior was measured with a magnetic sensor. After sleep and respiratory scoring, polysomnographic signals were computed as mean values over nonoverlapping 10-s intervals. The presence/absence of unintentional leakage was dichotomized for each 10-s interval (yes/no). Univariate and multivariate conditional regression models estimated the risk of unintentional leaks during an interval "T" based on the explanatory variables from the previous interval "T-1." A sensitivity analysis for the type of mask was then conducted. RESULTS: The univariate analysis showed that mandibular lowering (mouth opening), a high level of CPAP, body position (other than supine), and rapid eye movement (REM) sleep increased the risk of unintentional leaks and microarousal decreased it. In the multivariate analysis, the same variables remained independently associated with an increased risk of unintentional leakage. The sensitivity analysis showed that oronasal masks reduced the risk of unintentional leaks in cases of mouth opening and REM sleep. CONCLUSIONS: Mouth opening, CPAP level, sleep position, and REM sleep independently contribute to unintentional leakage. These results provide a strong rationale for the definition of phenotypes and the individual management of leaks during CPAP treatment.

Acceptance of Telemonitoring Among Patients with Obstructive Sleep Apnea Syndrome: How is the Perceived Interest by and for Patients?

BACKGROUND: Obstructive sleep apnea syndrome, a chronic respiratory disease, requires regular adherence to Continuous Positive Airway Pressure (CPAP) therapy. Telemonitoring may be relevant to support adherence, but nonetheless this raises ethical issues around the intrusive nature of the daily life of patients Objective: To explore the acceptance of telemonitoring by patients and the impact of this on adherence. MATERIALS AND METHODS: A prospective and observational study has been performed with 160 patients who initiated their CPAP therapy. The acceptability of telemonitoring was studied using an attitudes' scale of 8 items. A total of 160 patients (111 men, 49 women) responded to the questionnaire at 1 month upon treatment. The adoption of both telemonitoring and adherence behavior were observed at 10 months of therapy. RESULTS: A majority (78%) of patients expressed a favorable attitude toward telemonitoring, but nearly 40% consider this device like intrusive. However, at 10 months of treatment, 78% of patients are still telemonitored. We did not observe a significant difference between telemonitoring patients and nontelemonitoring patients with respect to the mean duration of use of CPAP therapy. However, the risk of stopping CPAP therapy is significantly more important in patients who refused telemonitoring. DISCUSSION AND CONCLUSION: It seems reductive to consider telemonitoring as a simple tool of surveillance to support adherence. It may be preferable to consider telemonitoring as a follow-up proposal. This will allow for more reactive management and close to the needs of the patients, in particular as telemonitoring is, in general, well accepted by patients.

Prevalence of obesity hypoventilation syndrome in ambulatory obese patients attending pathology laboratories.

BACKGROUND AND OBJECTIVE: The prevalence of obesity hypoventilation syndrome (OHS) in the unselected obese is unknown. Our objectives were: (i) to determine the prevalence of OHS in ambulatory obese patients not previously referred to a pulmonologist for suspicion of sleep breathing disorders and (ii) to assess whether venous bicarbonate concentration [HCO3-v ] can be used to detect OHS. METHODS: In this prospective multicentric study, we measured [HCO3-v ] in consenting obese patients attending pathology analysis laboratories. Patients with [HCO3-v ] ≥ 27 mmol/L were referred to a pulmonologist for comprehensive sleep and respiratory evaluations. Those with [HCO3-v ] < 27 mmol/L were randomized to either referral to a pulmonologist or ended the study. RESULTS: For the 1004 screened patients, the [HCO3-v ] was ≥27 mmol/L in 24.6% and <27 mmol/L in 45.9%. A total of 29.5% who had previously consulted a pulmonologist were excluded. A population of 241 obese patients underwent sleep and respiratory assessments. The prevalence of OHS in this population was 1.10 (95% CI = 0.51; 2.27). In multivariate analysis, PaCO2 , forced expiratory volume in 1 s (FEV1 ), apnoea-hypopnoea index (AHI), BMI, use of ≥3 anti-hypertensive drugs, anti-diabetics, proton pump inhibitors and/or paracetamol were related to raised [HCO3-v ]. CONCLUSION: The prevalence of OHS in our obese population was lower than previous estimations based on hospitalized patients or clinical cohorts with sleep breathing disorders. Apart from hypercapnia, increased [HCO3-v ] may also reflect multimorbidity and polypharmacy, which should be taken into account when using [HCO3-v ] to screen for OHS.

Factors Contributing to Unintentional Leak During CPAP Treatment: A Systematic Review.

CPAP is the first-line treatment for moderate to severe OSA syndrome. Up to 25% of patients with OSA syndrome discontinue CPAP treatment due to side effects. Unintentional leakage and its associated annoying consequences are the most frequently reported adverse effects of CPAP. Successive technological improvements have not succeeded in addressing this issue. A systematic review was conducted (1) to assess the impact of different technological advances on unintentional leaks and (2) to determine if any patient characteristics have already been identified as determinants of unintentional leakage. No CPAP modality was superior to another in reducing unintentional leaks and, surprisingly, oronasal masks were associated with higher unintentional leaks. Nasal obstruction, older age, higher BMI, central fat distribution, and male sex might be associated with an increased risk of unintentional leakage. Such leaks remain an important problem. Further studies are needed to improve the understanding of underlying clinical factors so that patients at risk of unintentional leaks may be identified and individualized solutions applied.

Nasal obstruction and male gender contribute to the persistence of mouth opening during sleep in CPAP-treated obstructive sleep apnoea.

BACKGROUND AND OBJECTIVE: During continuous positive airway pressure (CPAP) treatment, some patients with obstructive sleep apnoea syndrome (OSAS) require an oronasal mask (ONM) to prevent excessive mouth leakage. Factors contributing to sleep-related mouth opening under CPAP treatment remain known. We compared mouth opening during sleep in patients treated with CPAP by nasal mask (NM) versus ONM. METHODS: Cross-sectional prospective study: patients treated with CPAP for at least 4 months underwent a sleep recording using a type 4 monitoring device (Brizzy-Nomics) that records mouth opening via a magnetometric distance meter. Clinical assessment included anthropometry, smoking status and the Mallampati score. Nasal obstruction was assessed by the Nasal Obstruction Symptom Evaluation questionnaire. RESULTS: Thirty-eight patients were included, 34 analysed (22 men; age = 57.4 (53; 62) years; body mass index = 32.6 (29.1; 35.2) kg/m(2) ; median (25th; 75th)). Twenty-seven patients were treated with NM and seven with ONM. Patients with ONM were more often active smokers and trended to have greater nasal obstruction and lower forced expiratory volume in 1 s. They also exhibited a greater mouth opening during sleep (median (25th;75th) = 13.0 (11.0; 15.0) vs 6.0 (5.0; 10.0) mm, P < 0.001) and a higher oxygen desaturation index (9.5 (6.2; 15.5) vs 2.9 (1.0; 6.1) events/h, P = 0.009). In multivariate analysis, male gender and nasal obstruction were independently associated with mouth opening under ONM CPAP treatment. CONCLUSIONS: After several months of CPAP treatment, some patients using ONM persist in keeping their mouths open at night. Nasal obstruction and male gender contribute to this phenomenon.

Parameters recorded by software of non-invasive ventilators predict COPD exacerbation: a proof-of-concept study.

OBJECTIVE: To assess whether daily variations in three parameters recorded by non-invasive ventilation (NIV) software (respiratory rate (RR), percentage of respiratory cycles triggered by the patient (%Trigg) and NIV daily use) predict the risk of exacerbation in patients with chronic obstructive pulmonary disease (COPD) treated by home NIV. METHODS: Patients completed the EXACT-Pro questionnaire daily to detect exacerbations. The 25th and 75th percentiles of each 24 h NIV parameter were calculated and updated daily. For a given day, when the value of any parameter was >75th or <25th percentile, the day was marked as 'abnormal value' ('high value' >75th, 'low value' <25th). Stratified conditional logistic regressions estimated the risk of exacerbation when ≥2 days (for RR and %Trigg) or ≥3 days (for NIV use) out of five had an 'abnormal value'. RESULTS: Sixty-four patients were included. Twenty-one exacerbations were detected and medically confirmed. The risk of exacerbation was increased when RR (OR 5.6, 95% CI 1.4 to 22.4) and %Trigg (OR 4.0, 95% CI 1.1 to 14.5) were considered as 'high value' on ≥2 days out of five. CONCLUSIONS: This proof-of-concept study shows that daily variations in RR and %Trigg are predictors of an exacerbation.

Comparison of intraocular pressure measurements with the Reichert Pt100, the Keeler Pulsair Intellipuff portable noncontact tonometers, and Goldmann applanation tonometry.

PURPOSE: The aim of this study was to compare intraocular pressure (IOP) measurements using 2 portable tonometers, the Keeler Pulsair Intellipuff and the Reichert PT100, with Goldmann applanation tonometry (GAT). MATERIALS AND METHODS: Prospective cross-sectional study was conducted on normotensive and hypertensive patients recruited from the outpatient clinic of the University Hospital of Grenoble. IOP was measured using 2 portable noncontact tonometers (NCTs) and GAT in one eye of each patient in a random order. Central corneal thickness was measured with the Accutome PachPen Pachymeter. The Wilcoxon and t tests were used to compare the differences between tonometers, the Pearson and the Spearman correlation tests to evaluate the correlation among the methods, and the Bland-Altman plots to evaluate the agreement among the methods. Intraclass correlation coefficient (ICC) was used to evaluate the agreement among the methods in normotensive and hypertensive patients separately. RESULTS: A total of 137 eyes of 137 patients were included, 104 normotensive and 33 hypertensive eyes. We found an excellent agreement between PT100 and GAT (ICC=0.77) and between Intellipuff and GAT (ICC=0.75) in normotensive patients. We found a fair to good agreement (ICC=0.67) between PT100 and GAT in hypertensive patients. The agreement we found between Intellipuff and GAT was also excellent in hypertensive patients (ICC=0.86). Both NCTs significantly overestimated IOP measurements compared with GAT in normotensive and hypertensive eyes (mean of the differences between PT100 and GAT: 1.3±2.1 and 8.1±4.6 mm Hg in normotensive and in hypertensive patients, respectively (P<0.05), and between Pulsair Intellipuff and GAT: 1.5±1.8 and 2.3±4.8 mm Hg in normotensive and in hypertensive patients, respectively (P<0.05). CONCLUSIONS: The 2 NCTs agree well with GAT in normotensive patients. The Pulsair Intellipuff also agrees well with GAT in hypertensive patients.

Usefulness of oximetry for sleep apnea screening in frail hospitalized elderly.

BACKGROUND: Sleep Apnea Syndrome (SAS) prevalence increases with age. In the elderly, symptoms are less specific (falls, cognitive or functional decline, polymedication). Polysomnography, the gold standard technique to diagnose SAS, is challenged by sleep laboratories' waiting lists and high associated costs. Nocturnal oximetry is an easy-to-use tool widely available outside the sleep medicine field identifying intermittent hypoxia, the landmark of SAS. It might be an interesting and easy way to screen for SAS in the functionally and cognitively impaired elderly living in long-term care settings. OBJECTIVES: The primary goal of this study was to assess the accuracy of the variability index of nocturnal pulse oximetry to detect moderate to severe SAS in patients older than 75 hospitalized in stable condition. The secondary goals were to assess the accuracy of the other indices of pulse oximetry (oxygen desaturation index [ODI]), and to determine the prevalence of moderate to severe SAS in our population. METHODS: In-hospital sleep studies with simultaneous respiratory polygraphy and nocturnal pulse oximetry were performed. Comorbidities were assessed by the Cumulative Illness Rating Scale for Geriatrics (CIRS-G) in association with a comprehensive geriatric assessment. RESULTS: Eighty patients (mean age 85.3 ± 5.3 years) were included. Seventy-two percent of the patients exhibited moderate to severe SAS (95% CI 58.9-82.9), including 59.5% of severe SAS (apnea + hypopnea index >30/hour). SaO2 variability index using a threshold of 0.51, the sensitivity and negative predictive value (NPV) were 100%. With a value above 0.88, positive predictive value and specificity were high (respectively 96.6% and 93.8%). ODI of 3% or higher and 4% or higher were highly specific but less sensitive. CONCLUSION: Prevalence of moderate to severe SAS in multimorbid hospitalized elderly patients is high. Automatic analysis of the variability of nocturnal SaO2 is a reliable tool for geriatricians to screen and rule out moderate to severe SAS. Our study suggests an important role of pulse oximetry as the first step in the diagnostic strategy for moderate to severe SAS in this population.

Continuous response of optic nerve head blood flow to increase of arterial blood pressure in humans.

PURPOSE: This study investigates the effect of increased ocular perfusion pressure (OPP) on optic nerve head (ONH) hemodynamics. METHODS: In 21 healthy subjects, the increase in arterial blood pressure (BP), measured continuously using a pneumatic transcutaneous sensor, was produced by isometric exercise consisting of 2 minutes of hand-gripping. ONH blood flow parameters-namely the velocity (Vel), number (Vol), and flux (F) of red blood cells-were measured using the laser Doppler flowmeter (LDF). RESULTS: In those 14 healthy subjects who exhibited a similar increase in BP to handgrip superior to 30% of baseline BP, group average increases of BP and OPP amounted to 34% ± 3% (SEM) and 43% ± 3%, respectively. The increase in F of 19% ± 8%, resulting from an increase in Vel (17% ± 7%) and Vol (6% ± 7%), was significantly less than predicted for a passive autoregulatory response, as revealed also by the increase in vascular resistance (R = OPP/F). Spearman test of linear correlations between F and time during handgrip led to the identification of one group of eight subjects (with a stable F) and one group of six subjects (with an increase in F). A closed-loop gain (G) of the regulatory process, defined as G = 1 - {(F - Fbl)/Fbl}/{(OPP - OPPbl)/OPPbl}, was found to be rather independent from the OPP, with an average value 0.7 ± 0.07. G was 0.83 ± 0.06 for the group of eight subjects with stable F and 0.3 ± 0.15 for the group of six subjects with F increasing with the OPP. CONCLUSIONS: The continuous recording of both BP and LDFs represents a novel and more precise approach to the characterization of ONH hemodynamics during isometric exercise, especially useful in the future for patients with ocular diseases. The efficiency of the ONH blood flow autoregulation appears to vary significantly between healthy subjects. (ClinicalTrials.gov number, NCT00874913.).

Prognostic value of efficiently correcting nocturnal desaturations after one month of non-invasive ventilation in amyotrophic lateral sclerosis: a retrospective monocentre observational cohort study.

Abstract NIV adherence ('quantity' of ventilation) has a prognostic impact in amyotrophic lateral sclerosis (ALS). We hypothesized that NIV effectiveness ('quality') could also have a similar impact. NIV effectiveness was evaluated in 82 patients within the first month (M1) and every three months (symptoms, arterial blood bases, and nocturnal pulsed oxygen saturation - SpO2). Kaplan-Meier survival and risk factors for mortality one year after NIV initiation were evaluated. Forty patients were considered 'correctly ventilated' at M1 (Group 1, less than 5% of nocturnal oximetry time with an SpO2<90% - TS90) while 42 were not (Group 2). Both groups were comparable in terms of respiratory and neurological baseline characteristics. Survival was better in Group 1 (75% survival at 12 months) than in Group 2 (43% survival at 12 months, p = 0.002). In 12 Group 2 patients corrective measures were efficient in correcting TS90 at six months. In this subgroup, one-year mortality was not different from that in Group 1. Multivariate analysis identified independent mortality risk factors expectedly including bulbar involvement (HR = 4.31 (1.73 - 10.76), p = 0.002), 'rapid respiratory decline' (HR = 3.55 (1.29 - 9.75), p = 0.014) and vital capacity (HR = 0.97 (0.95 - 0.99), p = 0.010), but also inadequate ventilation in the first month (HR = 2.32 (1.09 - 4.94), p = 0.029). In conclusion, in ALS patients NIV effectiveness to correct nocturnal desaturations is an independent prognostic factor.

Noninvasive ventilation in mild obesity hypoventilation syndrome: a randomized controlled trial.

OBJECTIVE: Open studies suggest that treatment of obesity hypoventilation syndrome (OHS) by noninvasive ventilation (NIV) restores sleep quality and daytime vigilance and reduces cardiovascular morbidity. However, to our knowledge no randomized controlled trial (RCT) comparing NIV to conservative measures is available in the field. The goal of this study was to assess in patients with OHS, during an RCT, effects of 1-month NIV compared with lifestyle counseling on blood gas measurements, sleep quality, vigilance, and cardiovascular, metabolic, and inflammatory parameters. METHODS: Thirty-five patients in whom OHS was newly diagnosed were randomized either to the NIV group or the control group represented by lifestyle counseling. Assessments included blood gas levels, subjective daytime sleepiness, metabolic parameters, inflammatory (hsCRP, leptin, regulated upon activation normal T-cell express and secreted [RANTES], monocyte chemoattractant protein-1, IL-6, IL-8, tumor necrosis factor-α, resistin) and antiinflammatory (adiponectin, IL-1-RA) cytokines, sleep studies, endothelial function (reactive hyperemia measured by peripheral arterial tonometry [RH-PAT]), and arterial stiffness. RESULTS: Despite randomization, NIV group patients (n = 18) were older (58 ± 11 years vs 54 ± 6 years) with a higher baseline Paco(2) (47.9 ± 4.2 mm Hg vs 45.2 ± 3 mm Hg). In intention-to-treat analysis, compared with control group, NIV treatment significantly reduced daytime Paco(2) (difference between treatments: -3.5 mm Hg; 95% CI, -6.2 to -0.8) and apnea-hypopnea index (-40.3/h; 95% CI, -62.4 to -18.2). Sleep architecture was restored, although nonrespiratory microarousals increased (+9.4/h of sleep; 95% CI, 1.9-16.9), and daytime sleepiness was not completely normalized. Despite a dramatic improvement in sleep hypoxemia, glucidic and lipidic metabolism parameters as well as cytokine profiles did not vary significantly. Accordingly, neither RH-PAT (+0.02; 95% CI, -0.24 to 0.29) nor arterial stiffness (+0.22 m/s; 95% CI, -1.47 to 1.92) improved. CONCLUSIONS: One month of NIV treatment, although improving sleep and blood gas measurements dramatically, did not change inflammatory, metabolic, and cardiovascular markers. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT00603096; URL: www.clinicaltrials.gov.