Echocardiographic Changes with Positive Airway Pressure Therapy in Obesity Hypoventilation Syndrome. Long-Term Pickwick Randomized Controlled Clinical Trial

Spanish Sleep Network.[Rationale] Obesity hypoventilation syndrome (OHS) has been associated with cardiac dysfunction. However, randomized trials assessing the impact of long-term noninvasive ventilation (NIV) or continuous positive airway pressure (CPAP) on cardiac structure and function assessed by echocardiography are lacking. Rationale: Obesity hypoventilation syndrome (OHS) has been associated with cardiac dysfunction. However, randomized trials assessing the impact of long-term noninvasive ventilation (NIV) or continuous positive airway pressure (CPAP) on cardiac structure and function assessed by echocardiography are lacking.[Objectives] In a prespecified secondary analysis of the largest multicenter randomized controlled trial of OHS (Pickwick Project; N = 221 patients with OHS and coexistent severe obstructive sleep apnea), we compared the effectiveness of three years of NIV and CPAP on structural and functional echocardiographic changes.[Methods] At baseline and annually during three sequential years, patients underwent transthoracic two-dimensional and Doppler echocardiography. Echocardiographers at each site were blinded to the treatment allocation. Statistical analysis was performed using a linear mixed-effects model with a treatment group and repeated measures interaction to determine the differential effect between CPAP and NIV. Measurements and Main Results: A total of 196 patients were analyzed: 102 were treated with CPAP and 94 were treated with NIV. Systolic pulmonary artery pressure decreased from 40.5 ± 1.47 mm Hg at baseline to 35.3 ± 1.33 mm Hg at three years with CPAP, and from 41.5 ± 1.56 mm Hg to 35.5 ± 1.42 with NIV (P < 0.0001 for longitudinal intragroup changes for both treatment arms). However, there were no significant differences between groups. NIV and CPAP therapies similarly improved left ventricular diastolic dysfunction and reduced left atrial diameter. Both NIV and CPAP improved respiratory function and dyspnea.[Conclusions] In patients with OHS who have concomitant severe obstructive sleep apnea, long-term treatment with NIV and CPAP led to similar degrees of improvement in pulmonary hypertension and left ventricular diastolic dysfunction

Risk factors associated with pulmonary hypertension in obesity hypoventilation syndrome

Pulmonary hypertension (PH) is prevalent in obesity hypoventilation syndrome (OHS). However, there is a paucity of data assessing pathogenic factors associated with PH. Our objective is to assess risk factors that may be involved in the pathogenesis of PH in untreated OHS.Peer reviewe

The Effect of Supplemental Oxygen in Obesity Hypoventilation Syndrome.

Low flow supplemental oxygen is commonly prescribed to patients with obesity hypoventilation syndrome (OHS). However, there is a paucity of data regarding its efficacy and safety. The objective of this study was to assess the medium-term treatment efficacy of adding supplemental oxygen therapy to commonly prescribed treatment modalities in OHS. In this post hoc analysis of a previous randomized controlled trial, we studied 302 sequentially screened OHS patients who were randomly assigned to noninvasive ventilation, continuous positive airway pressure, or lifestyle modification. Outcomes at 2 mo included arterial blood gases, symptoms, quality of life, blood pressure, polysomnography, spirometry, 6-min walk distance, and hospital resource utilization. Statistical analysis comparing patients with and without oxygen therapy in the three treatment groups was performed using an intention-to-treat analysis. In the noninvasive ventilation group, supplemental oxygen reduced systolic blood pressure although this could be also explained by a reduction in body weight experienced in this group. In the continuous positive airway pressure group, supplemental oxygen increased the frequency of morning confusion. In the lifestyle modification group, supplemental oxygen increased compensatory metabolic alkalosis and decreased the apnea-hypopnea index during sleep. Oxygen therapy was not associated with an increase in hospital resource utilization in any of the groups. After 2 mo of follow-up, chronic oxygen therapy produced marginal changes that were insufficient to consider it, globally, as beneficial or deleterious. Because supplemental oxygen therapy did not increase hospital resource utilization, we recommend prescribing oxygen therapy to patients with OHS who meet criteria with close monitoring. Long-term studies examining outcomes such as incident cardiovascular morbidity and mortality are necessary. Clinicaltrial.gov, ID: NCT01405976

Effect of continuous positive airway pressure in patients with true refractory hypertension and sleep apnea: a post-hoc intention-to-treat analysis of the HIPARCO randomized clinical trial

Spanish Sleep Network.[Rationale] Continuous positive airway pressure (CPAP) can significantly reduce blood pressure (BP) levels in patients with resistant hypertension and sleep apnea (OSA); however, the effect on patients with refractory hypertension (RfH) is not known. This study seeks to evaluate the effect of CPAP treatment on BP levels in patients with OSA and RfH, compared with those with OSA and resistant hypertension.[Methods] Post-hoc analysis of the HIPARCO randomized clinical trial on the effect of CPAP treatment on BP levels in patients with resistant hypertension. Those patients with uncontrolled 24-h ambulatory BP monitoring readings (>130 and/or >80 mmHg) in SBP or DBP were considered to have resistant hypertension (if they were taking three or four antihypertensive drugs) or RfH (if they were taking at least five drugs). OSA patients were randomized to receive CPAP or usual care for 3 months. They underwent a second 24-h ambulatory BP monitoring study to establish the effect of CPAP treatment on BP levels in both groups.[Results] A total of 98 patients were randomized to CPAP (19 RfH/79 resistant hypertension) and 96 to usual care (21 RfH/75 resistant hypertension). BP readings dropped more marked in patients with RfH than resistant hypertension, in both 24-h SBP (−9 vs. −1.6 mmHg, P = 0.021) and 24-h DBP (−7.3 vs. −2.3 mmHg, P = 0.074), especially at night (−11.3 vs. −3.8, P = 0.121 and −8.8 vs. −2.2, P = 0.054) respectively. Adjusted difference between groups was statistically significant in 24-h SBP levels (−7.4 mmHg, P = 0.021).[Conclusion] CPAP lowers BP levels in both resistant hypertension and RfH patients although the degree of this reduction is higher in those with RfH especially during the night

Echocardiographic changes with non-invasive ventilation and CPAP in obesity hypoventilation syndrome.

Despite a significant association between obesity hypoventilation syndrome (OHS) and cardiac dysfunction, no randomised trials have assessed the impact of non-invasive ventilation (NIV) or CPAP on cardiac structure and function assessed by echocardiography. We performed a secondary analysis of the data from the largest multicentre randomised controlled trial of OHS (Pickwick project, n=221) to determine the comparative efficacy of 2 months of NIV (n=71), CPAP (n=80) and lifestyle modification (control group, n=70) on structural and functional echocardiographic changes. Conventional transthoracic two-dimensional and Doppler echocardiograms were obtained at baseline and after 2 months. Echocardiographers at each site were blinded to the treatment arms. Statistical analysis was performed using intention-to-treat analysis. At baseline, 55% of patients had pulmonary hypertension and 51% had evidence of left ventricular hypertrophy. Treatment with NIV, but not CPAP, lowered systolic pulmonary artery pressure (-3.4 mm Hg, 95% CI -5.3 to -1.5; adjusted P=0.025 vs control and P=0.033 vs CPAP). The degree of improvement in systolic pulmonary artery pressure was greater in patients treated with NIV who had pulmonary hypertension at baseline (-6.4 mm Hg, 95% CI -9 to -3.8). Only NIV therapy decreased left ventricular hypertrophy with a significant reduction in left ventricular mass index (-5.7 g/m2; 95% CI -11.0 to -4.4). After adjusted analysis, NIV was superior to control group in improving left ventricular mass index (P=0.015). Only treatment with NIV led to a significant improvement in 6 min walk distance (32 m; 95% CI 19 to 46). In patients with OHS, medium-term treatment with NIV is more effective than CPAP and lifestyle modification in improving pulmonary hypertension, left ventricular hypertrophy and functional outcomes. Long-term studies are needed to confirm these results. Pre-results, NCT01405976 (https://clinicaltrials.gov/)

El impacto de la terapia de presión positiva de larga duración en el síndrome de hipoventilación-obesidad en función de la gravedad de la enfermedad

[Rationale] Obesity hypoventilation syndrome (OHS) with concomitant severe obstructive sleep apnea (OSA) is treated with CPAP or noninvasive ventilation (NIV) during sleep. NIV is costlier, but may be advantageous because it provides ventilatory support. However, there are no long-term trials comparing these treatment modalities based on OHS severity.[Objective] To determine if CPAP have similar effectiveness when compared to NIV according to OHS severity subgroups.[Methods] Post hoc analysis of the Pickwick randomized clinical trial in which 215 ambulatory patients with untreated OHS and concomitant severe OSA, defined as apnoea-hypopnea index (AHI) ≥ 30 events/h, were allocated to NIV or CPAP. In the present analysis, the Pickwick cohort was divided in severity subgroups based on the degree of baseline daytime hypercapnia (PaCO2 of 45–49.9 or ≥50 mmHg). Repeated measures of PaCO2 and PaO2 during the subsequent 3 years were compared between CPAP and NIV in the two severity subgroups. Statistical analysis was performed using linear mixed-effects model.[Results] 204 patients, 97 in the NIV group and 107 in the CPAP group were analyzed. The longitudinal improvements of PaCO2 and PaO2 were similar between CPAP and NIV based on the PaCO2 severity subgroups.[Conclusion] In ambulatory patients with OHS and concomitant severe OSA who were treated with NIV or CPAP, long-term NIV therapy was similar to CPAP in improving awake hypercapnia, regardless of the severity of baseline hypercapnia. Therefore, in this patient population, the decision to prescribe CPAP or NIV cannot be solely based on the presenting level of PaCO2.[Introducción] El síndrome de hipoventilación-obesidad (SHO) con apnea obstructiva del sueño (AOS) grave concomitante se trata con CPAPo ventilación no invasiva (VNI) durante el sueño. La VNI es más costosa, pero puede ser beneficiosa porque proporciona soporte ventilatorio; sin embargo, no existen estudios a largo plazo que comparen estas modalidades de tratamiento basándose en la gravedad del SHO.[Objetivo] Determinar si la CPAP tiene una eficacia similar a la VNI según los subgrupos de gravedad del SHO.[Métodos] Análisis a posteriori del ensayo clínico aleatorizado Pickwick en el que 215 pacientes ambulatorios con SHO sin tratar y con AOS grave concomitante (definida como un índice de apnea-hipopnea [IAH] ≥ 30 episodios/hora) recibieron tratamiento con VNI o CPAP. En el presente análisis, la cohorte Pickwick se dividió en subgrupos según la gravedad basándose en el grado de hipercapnia diurna al inicio del estudio (PaCO2 de 45-49.9 mm Hg o ≥ 50 mm Hg). Se compararon las mediciones periódicas de PaCO2 y PaO2 durante los 3 años siguientes entre la CPAP y la VNI entre los dos subgrupos de gravedad. Se realizó un análisis estadístico utilizando un modelo lineal mixto.[Resultados] Se analizaron 204 pacientes, 97 en el grupo de VNI y 107 en el grupo de CPAP. Las mejoras lineales de PaCO2 y PaO2 fueron similares entre la CPAP y la NIV según los subgrupos de gravedad en función de la PaCO2.[Conclusión] En los pacientes ambulatorios con SHO y AOS grave concomitante a los que se trató con VNI o CPAP, el tratamiento a largo plazo con VNI resultó similar a la CPAP, en cuanto a la mejora de la hipercapnia en vigilia, independientemente de la gravedad de la hipercapnia de inicio. Por lo tanto, en esta población de pacientes la decisión de prescribir CPAP o VNI no puede basarse exclusivamente en el nivel de partida de PaCO2.Instituto de Salud Carlos III (Fondo de Investigaciones Sanitarias, Ministerio de Sanidad y Consumo, Madrid, Spain) PI050402, Spanish Respiratory Foundation 2005 (FEPAR) and Air Liquide Spain.Peer reviewe

Long-term clinical effectiveness of continuous positive airway pressure therapy versus non-invasive ventilation therapy in patients with obesity hypoventilation syndrome: a multicentre, open-label, randomised controlled trial

Spanish Sleep Network: Galo Fernández, Estrella Ordax-Carbajo, Nicolás González-Mangado, Teresa Gómez-García, María-Ángeles Martínez-Martínez, Elena Ojeda-Castillejo, Daniel López Padilla, Santiago J Carrizo, Begoña Gallego, Mercedes Pallero, Odile Romero, María Antonia Ramón, Eva Arias, Jesús Muñoz-Méndez, Cristina Senent, José N.Sancho-Chust, Nieves Belén Navarro Soriano, Emilia Barrot, José M. Benítez, Jesús Sánchez-Gómez, Rafael Golpe, Ana Santiago-Recuerda Silvia Gómez, Mónica Bengoa.[Background] Obesity hypoventilation syndrome is commonly treated with continuous positive airway pressure or non-invasive ventilation during sleep. Non-invasive ventilation is more complex and costly than continuous positive airway pressure but might be advantageous because it provides ventilatory support. To date there have been no long-term trials comparing these treatment modalities. We therefore aimed to determine the long-term comparative effectiveness of both treatment modalities.[Methods] We did a multicentre, open-label, randomised controlled trial at 16 clinical sites in Spain. We included patients aged 15–80 years with untreated obesity hypoventilation syndrome and an apnoea-hypopnoea index of 30 or more events per h. We randomly assigned patients, using simple randomisation through an electronic database, to receive treatment with either non-invasive ventilation or continuous positive airway pressure. Both investigators and patients were aware of the treatment allocation. The research team was not involved in deciding hospital treatment, duration of treatment in the hospital, and adjustment of medications, as well as adjudicating cardiovascular events or cause of mortality. Treating clinicians from the routine care team were not aware of the treatment allocation. The primary outcome was the number of hospitalisation days per year. The analysis was done according to the intention-to-treat principle. This study is registered with ClinicalTrials.gov, number NCT01405976.[Findings] From May 4, 2009, to March 25, 2013, 100 patients were randomly assigned to the non-invasive ventilation group and 115 to the continuous positive airway pressure group, of which 97 patients in the non-invasive ventilation group and 107 in the continuous positive airway pressure group were included in the analysis. The median follow-up was 5·44 years (IQR 4·45–6·37) for all patients, 5·37 years (4·36–6·32) in the continuous positive airway pressure group, and 5·55 years (4·53–6·50) in the non-invasive ventilation group. The mean hospitalisation days per patient-year were 1·63 (SD 3·74) in the continuous positive airway pressure group and 1·44 (3·07) in the non-invasive ventilation group (adjusted rate ratio 0·78, 95% CI 0·34–1·77; p=0·561). Adverse events were similar between both groups.[Interpretation] In stable patients with obesity hypoventilation syndrome and severe obstructive sleep apnoea, non-invasive ventilation and continuous positive airway pressure have similar long-term effectiveness. Given that continuous positive airway pressure has lower complexity and cost, continuous positive airway pressure might be the preferred first-line positive airway pressure treatment modality until more studies become available.This study was funded by the Instituto de Salud Carlos III (Fondo de Investigaciones Sanitarias, Ministerio de Sanidad y Consumo; number PI050402), Spanish Respiratory Foundation 2005 (FEPAR), and Air Liquide Spain.Peer reviewe

Soluble PD-L1 is a potential biomarker of cutaneous melanoma aggressiveness and metastasis in obstructive sleep apnoea patients

Obstructive sleep apnoea (OSA) upregulates the programmed cell death-1 receptor and its ligand (PD-L1) pathway, potentially compromising immunosurveillance. We compared circulating levels of soluble PD-L1 (sPD-L1) in patients with cutaneous melanoma according to the presence and severity of OSA, and evaluated relationships with tumour aggressiveness and invasiveness. In a multicentre observational study, 360 patients with cutaneous melanoma underwent sleep studies, and serum sPD-L1 levels were assayed using ELISA. Cutaneous melanoma aggressiveness indices included mitotic rate, Breslow index, tumour ulceration, Clark level and tumour stage, and sentinel lymph node (SLN) metastasis was recorded as a marker of invasiveness. sPD-L1 levels were higher in severe OSA compared to mild OSA or non-OSA patients. In OSA patients, sPD-L1 levels correlated with Breslow index and were higher in patients with tumour ulceration, advanced primary tumour stages or with locoregional disease. The incorporation of sPD-L1 to the classic risk factors to SLN metastasis led to net improvements in the classification of 27.3%. Thus, sPD-L1 levels are increased in melanoma patients with severe OSA, and, in addition, might serve as a potential biomarker of cutaneous melanoma aggressiveness and invasiveness in this group of subjects