"Post-acute Pickwick Study" (Postacute-Pick-2020)

We propose to carry out a large multicentric, multinational, randomized controlled trial with two phases (two sequential randomized controled trials) to answer two questions: 1) Should hospitalized patients with recently diagnosed OHS be discharged from the hospital on an auto-titratable NIV treatment until the diagnosis of OHS is confirmed in 3 months? 2) Is the long-term effectiveness of outpatient titrated CPAP non-inferior to titrated NIV in ambulatory patients with OHS 3 months after hospital discharge? Clinical practice, multicenter open-label controlled randomized clinical trial with preset allocation rate (1:1) with two parallel-groups conducted in centers from Spain, France, Portugal and USA. The study will have two phases with two randomizations. The first phase will be a superiority study and the second phase will be a non-inferiority study.

Objectives: First phase (medium-term): To evaluate the medium-term (3 months) efficacy of automatically adjusted noninvasive ventilation (NIV) treatment versus "life style modifications" treatment in obesity hypoventilation syndrome (OHS) after an episode of acute-on-chronic hypercapnic respiratory failure. The main outcome will be a composite that includes hospital resource utilization (hospital and ICU admissions and emergency department visits for any cause) and all-cause mortality. Key secondary outcomes will include incident cardiovascular events (new hypertension diagnosis or initiation of anti-hypertensive treatment, atrial fibrillation, hospitalization for nonfatal myocardial infarction or unstable angina, percutaneous coronary interventions, nonfatal stroke or transient ischemic attack or for acute heart failure episode, and cardiovascular death), blood pressure, arterial blood gases, clinical symptoms and quality of life. Second phase (long-term): Evaluate the long-term efficacy (36 months) of manually titrated NIV treatment versus manually titrated CPAP treatment in OHS after 3 months of an episode of acute-on-chronic hypercapnic respiratory failure, with a composite outcome of hospital resource utilization (hospital and ICU admissions, emergency department visits) and all-cause mortality analyzed as the primary outcome. Incident cardiovascular events, blood pressure, arterial blood gases, clinical symptoms and quality of life will be the main secondary outcomes.

Methods: Prospective, multinational, randomized open-label controlled trial with two parallel arms: 1,110 hospitalized patients with newly diagnosed OHS with acute-on-chronic hypercapnic respiratory failure treated with invasive or noninvasive mechanical ventilation who survive hospitalization and available for hospital discharge will be randomized to either automatically adjusted NIV (555 patients) or "life style modifications" (555 patients) for three months. Subsequently, both automatically adjusted NIV and "life style modifications" arms will be re-randomized to polysomnographically adjusted CPAP or to polysomnographically adjusted NIV groups to complete 36 months of follow up. The first phase of the proposal is a superiority study and the second phase is a non-inferiority study. The primary outcome and its components will be analyzed by a mixed-effects model with negative binomial. A mixed-effects Cox model will be used for hospital resource utilization, new cardiovascular events and overall survival. Other secondary outcomes such as repeated measures derived from the arterial blood gases (i.e. PaCO2, PaO2, pH, calculated bicarbonate), blood pressure, health-related quality of life tests and Epworth Sleepiness Scale during the follow-up will be analyzed by a linear mixed-effects model.

Eligibility Criteria:
Inclusion Criteria:

1. º.- Patient between 18 and 85 years old.
2. º.- With diagnosis of OHS (according to Obesity (BMI ≥30 kg/m2) and Hypercapnic respiratory failure (PaCO2 ≥45 mmHg at hospital discharge) not secondary to other causes.
3. º - Hospitalized for an episode of acute-on-chronic hypercapnic respiratory failure, receiving hospital therapy with invasive or noninvasive ventilation, and just deemed stable for home discharge."
4. º.- No NIV or CPAP home therapy in the last 6 months\[\*\].
5. º.- Being able to tolerate and correctly execute a 15-minute test with automatic NIV (AVAPS-AE) and another 15-minute test with fixed CPAP treatments during wakefulness.
6. º.- Providing informed consent (dated and signed).

\[\*\] Patients who have objective evidence of minimal PAP therapy during the 6 months prior to hospital admission (i.e. average daily use of less than 2 hours of PAP therapy) can also be enrolled at the discretion of the investigators if they feel the patient is now more interested in being adherent to NIV therapy.

Inclusion criteria for the second phase of the study:

1º.- Included three months ago in the first phase of the study (followed by a washout period of 5 days).

Exclusion Criteria:

Exclusion criteria for the first phase of the study:

1. º.- With moderate or severe chronic obstructive pulmonary disease (FEV1\<70% of predicted when FEV1/FVC is below 70%).
2. º.- With neuromuscular disease, thoracic wall or metabolic disease that may cause diurnal hypercapnia.
3. º.- Inability to maintain a patent airway or adequately clear secretions.
4. º.- With bullous lung disease or with pneumothorax.
5. º.- With bypassed upper airway (i.e. endotracheal tube or tracheostomy).
6. º.- With anatomical abnormalities of the craniofacial structure leading to cerebral spinal fluid leaks, abnormalities of the cribriform plate, and/or pneumocephalus.
7. º.- At risk for aspiration of gastric contents.
8. º.- Diagnosed with acute sinusitis or otitis media.
9. º.- With active hemoptysis or epistaxis if presenting a risk of causing pulmonary aspiration of blood.
10. º.- With symptomatic hypotension.
11. º.- With clinical diagnosis of narcolepsy or restless leg syndrome.
12. º.- Psycho-physical incapacity to complete questionnaires.
13. º.- With diagnosis of chronic illness that might interfere the evaluation using quality of life questionnaires (neoplasia, severe chronic pain of any type, and any other severe chronic debilitating illness).
14. º.- Suffering other clinically relevant disease that, under the opinion of the investigator, might affect the evaluations of efficacy or safety.
15. º.- Participating simultaneously in other clinical study with intervention (or without intervention at the discretion of the investigator and with the consent of the Sponsor) or had participated in other clinical study with intervention within the last 30 days before the inclusion in this study. \[‡\]
16. º.- If for any reason (planned surgery \[including bariatric surgery\], trips of long duration, etc.) would not be able to receive the treatment and/or attend the follow-up visits of this study within the next three years and three months.
17. º.- Persons deprived of liberty by judicial or administrative decision, persons under psychiatric treatment and persons placed in a health or social institution for purposes other than those of this clinical study.
18. º.- Adults who are subject to a legal protection measure or who are unable to express their consent.

\[‡\] This prohibition shall be maintained for the duration of the patients' participation in the study. This is because, if patients received other treatments, it could be difficult to interpret the causality of the results obtained (whether beneficial or harmful effects) and the possible contraindications.

vi. Exclusion criteria for the second phase of the study:

1º.- With apnea hypopnea index (AHI) lower than 5 (absence or very mild obstructive sleep apnea).