Clinical Research Directory

The Cardiovascular Consequences of Sleep Apnea Plus COPD (Overlap Syndrome)

Major progress has been made in the area of cardiovascular disease, but we believe that further progress will involve mechanistically addressing underlying respiratory causes including chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA). The most common cause of death in COPD is cardiovascular, although mechanisms are unknown. OSA has been associated with major neurocognitive and cardiovascular sequelae, the latter likely a function of autonomic nervous system abnormalities, oxidative stress, inflammation, and other pathways. Recent data suggest that individuals with OVS die preferentially of cardiovascular disease compared to OSA or COPD alone, although mechanisms are again unclear. The combination of OSA and COPD may lead to profound hypoxemia. Individuals with COPD can develop pulmonary hypertension via disturbances in gas exchange and parenchymal injury leading to loss of pulmonary vasculature. OSA has been associated with mild to moderate pulmonary hypertension, but the situation may be worse if combined with parenchymal lung disease. The biological response to sustained hypoxemia has been carefully studied as has the topic of intermittent hypoxemia; however, to our knowledge, very little research has occurred regarding the combination of sustained plus intermittent hypoxia as seen in OVS. For example, we do not really know whether individuals with OVS develop coronary disease, right or left heart failure, dysrhythmias or some combination of abnormalities predisposing them to cardiovascular death. Thus, design of interventional studies is challenging as causal pathways are poorly understood despite our considerable preliminary data addressing these issues. The purpose of this study is to examine vascular mechanisms in individuals with COPD/OSA overlap syndrome (OVS) compared with matched individuals with obstructive sleep apnea (OSA) alone or chronic obstructive pulmonary disease (COPD) alone and to perform a phase II pilot mechanistic clinical trial in OVS to examine the effect size of nocturnal bi-level positive airway pressure (PAP) vs. nocturnal oxygen therapy in cardiovascular outcomes.

Impact of Positive Airway Pressure Therapy on Clinical Outcomes in Older Veterans With Chronic Obstructive Pulmonary Disease and Comorbid Obstructive Sleep Apnea (Overlap Syndrome)

Obstructive sleep apnea (OSA) and Chronic Obstructive Pulmonary Disease (COPD) are highly prevalent chronic respiratory diseases in the Veteran population. OSA co-occurring with COPD, known as Overlap Syndrome (OVS), is a complex chronic medical condition associated with grave consequences. OVS is highly prevalent in Veterans. Veterans with OVS may be at increased risk for cognitive deficits, poor sleep quality as well as a reduced quality of life (QoL). The overall objective is to study the effects of positive airway pressure therapy on clinical outcomes in patients with OVS.

LYell SYndrome MEsenchymal Stromal Cells Treatment

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare severe cutaneous adverse reactions (SCARs) to drugs. To date, no curative drug has demonstrated with a good level of evidence its ability to promote SJS and TEN healing and could contribute to earlier reepithelialisation. Mesenchymal stroma cells (MSCs) therapy represents a new therapeutic approach. eg, in patients with cardiovascular diseases, neurological diseases, renal transplantation, lung diseases as acute respiratory distress syndrome. Recently, MSCs have been proposed in both burn wound healing with a significantly decrease of the unhealed burn area and in cutaneous radiation. Moreover, MSCs have immunomodulation properties potentially effective in refractory acute and chronic graft versus host disease (GVHD) by improving thymic function and induction of Tregs. Indeed, MSCs are able to migrate to inflamed tissues after stimulation by pro-inflammatory cytokines and to modulate the local inflammatory reactions. MSCs have also demonstrated their ability to promote tissue remodelling, angiogenesis and immunomodulation through either differentiation or secretion of several growth factors such as VEGF, basic FGF and various cytokines. Therefore, combining their immunomodulation effect and secretion of soluble factors involved in wound repair, MSCs might be valuable as a cell therapy strategy for promoting cutaneous healing in SJS-TEN syndrome and subsequently decrease the morbi-mortality.

Impact of Continuous Positive Airway Pressure on the Occurrence of Acute Exacerbations of COPD in Patients With COPD-OSA Overlap Syndrome (CO-OS)

Chronic Obstructive Pulmonary Disease (COPD) and Obstructive Sleep Apnea (OSA) are both frequent respiratory diseases with estimated prevalences between 8 and 15% of the adult population. Because of those high prevalences those two entities are often associated in same patients (1 to 4% of the general population). This association is then referred to as Overlap Syndrome (CO-OS). Data from observational studies suggest that this association may have an additive or even synergistic negative impact on patient's prognosis. Indeed, in a cohort of patients diagnosed as having a CO-OS, patients who did not receive specific treatment for OSA had a 76% increased risk of death compared to patients treated with continuous positive airway pressure (CPAP) and a 2-fold increased risk of acute COPD exacerbation. In another cohort of patients with both OSA and severe oxygen treated COPD, untreated patients for OSA had a 5-fold increased risk of death compared to patients treated with CPAP. There are strong signals from observational studies in support of a beneficial impact of CPAP therapy on respiratory outcomes in patients with CO-OS. However, those findings are not supported by any controlled study. It is difficult to directly transpose the observational data to current clinical practice in the context of the recent studies on the impact of CPAP on OSA prognosis. Indeed, data from similar observational OSA cohorts have reported a major impact of CPAP on the overall survival and cardiovascular outcomes in patients with OSA. Ten years later, this impact has not been confirmed by several randomized studies. To date, there is no consensus on a systematic screening and, if present, management of OSA in patients with COPD. The need for specific research on that field was emphasized in 2018 in an official American Thoracic Society Research Statement which recommends "randomized trials that compare clinical outcomes among patients with Overlap Syndrome whose OSA is treated to clinical outcomes among patients with Overlap Syndrome whose OSA is untreated".

Canadian Network for Autoimmune Liver Disease

CaNAL is a longitudinal observational cohort study of patients diagnosed with Primary Biliary Cholangitis (PBC), Autoimmune Hepatitis (AIH), or overlap syndrome. This study creates a nationwide registry and network focusing on high quality long-term follow-up of individual patient data from major Canadian centers. Primary Biliary Cholangitis (PBC) and Autoimmune Hepatitis (AIH) are rare and slowly progressive liver diseases associated with development of cirrhosis, liver cancer (HCC) and liver failure requiring liver transplantation or leading to premature death. The rarity and slowly progressive nature of these autoimmune liver diseases make them difficult to study and only a large scale approach combining patient data from multiple centers across Canada will allow new insights. The primary aim of the Canadian Network for Autoimmune Liver Disease is to build a Canadian registry of patients with PBC, AIH, and overlap syndrome. We capture patient characteristics, laboratory assessments and natural history, patient-reported outcomes including quality of life measures and environmental exposures, response to treatment, and pre- and post-transplant outcomes. We will then identify risk factors associated with critical outcomes for the patient, including response to treatment, progression to transplant, risk of liver cancer, and recurrent disease after transplant. We can identify biomarkers (biochemical indicators of progression of disease) to help diagnose autoimmune liver disease at its earliest stages, ensuring timely treatment and preventing disease progression. CaNAL will provide a better understanding of autoimmune liver diseases, biomarkers predictive of disease progression or non-response to therapy as well as better knowledge of the etiology and pathogenesis. CaNAL will also help to serve as a platform for conducting clinical trials or targeted lab-studies to answer important questions that are unlikely to be evaluated by the pharmaceutical industry.