Research Marijke Dieltjens

Abstract

Obstructive sleep apnea (OSA) is a prevalent public health issue associated with an increased risk for cardio- and cerebrovascular diseases. The assessment of severity and management of OSA remains mainly confined to the apnea/hypopnea index (AHI) metric, providing a simple count of apneas and hypopneas per hour of sleep. Nowadays, OSA is increasingly recognized as a complex and heterogeneous disorder both regarding underlying pathophysiological mechanisms (endotypes) as in terms of clinical manifestations and susceptibility to comorbidities (phenotypes). In this research project, we want to gain insight in and understanding of the endophenotypic variance in OSA with a focus on the underlying pathophysiological traits and cardiovascular alterations of OSA. To capture the variability in OSA endophenotypes, we will consider novel metrics that improve and expand upon the AHI for the diagnosis and severity classification of OSA, with special attention for sleep apnea specific hypoxic burden (SASHB), sleep apnea specific heart-rate response (?HR) and pulse wave amplitude drops (PWADs) as these were previously correlated with cardiovascular risk. Furthermore, since the effect of treatment on the cardiovascular parameters remains a major interest of the field, we will assess the effect of various treatment modalities on cardiovascular remodeling, including continuous positive airway pressure (CPAP), mandibular advancement devices (MAD) and hypoglossal nerve stimulation (HNS).

Researcher(s)

• Promoter: Dieltjens Marijke
• Co-promoter: Op de Beeck Sara

Research team(s)

• Translational Neurosciences (TNW)

Project type(s)

• Research Project

Abstract

Obstructive sleep apnea (OSA) is a prevalent public health issue with an attributable risk of cardio- and cerebrovascular morbidity and mortality. Furthermore, OSA is related to a high socioeconomic burden due to its clinical daytime consequences such as excessive daytime sleepiness, impaired cognitive performance and reduced quality of life. Oral appliances that protrude the mandible, the mandibular advancement devices (MAD), significantly reduce OSA severity in the majority of patients. However, in a third of patients, the efficacy is not medically appropriate to reduce the long-term consequences of OSA. Furthermore, the efficacy of MAD therapy is inconsistent among patients. Therefore, a high need exists for upfront prediction of treatment outcome in the individual OSA patient. There is no validated method that can achieve upfront selection of candidates for MAD therapy in an accurate and reliable way. Nowadays, it is increasingly recognized that OSA is a multifactorial disease. In the proposed research project, a prospective prediction model with a combination of different pathophysiological traits will be assessed. Furthermore, up to now, our understanding of MAD therapy relies on relatively small studies lacking power. Therefore, we will evaluate this predictive model, as well as the long-term effectiveness, morbidity and mortality in a large international cohort of patients treated with MAD.

Researcher(s)

• Promoter: Vanderveken Olivier
• Co-promoter: Braem Marc
• Co-promoter: Verbraecken Johan
• Fellow: Dieltjens Marijke

Research team(s)

• Translational Neurosciences (TNW)

Project type(s)

• Research Project

Abstract

Obstructive sleep apnea (OSA) is a prevalent public health issue and strong and independent risk factor for cardio- and cerebrovascular diseases. Therefore, adequate treatment is important. Continuous positive airway pressure (CPAP) is considered the gold standard non-invasive treatment modality, although oral appliances that protrude the mandible are increasingly prescribed. Both non-invasive treatment modalities are symptomatic treatments and therefore lifelong device therapies, so the patient's compliance is of primary importance since it is only effective when appropriately used. The therapeutic effectiveness of both therapies is given by the product of efficacy with objective compliance. For both CPAP and oral appliance therapies, it is important to determine the therapeutic effectiveness in the optimal 'dose', being pressure for CPAP and mandibular protrusion for oral appliances. However, in the absence of a gold standard protocol to find the optimal mandibular protrusion for oral appliance therapy, the titration procedure remains 'trial and error'. Therefore, in the proposed research project, the feasibility of a titration procedure during polysomnography will be assessed and compared with a titration procedure under direct visualization of upper airway collapse during drug-induced sedation endoscopy, for both therapies. Furthermore, the pathophysiologic and cardiovascular alterations during both treatment modalities in the established optimal dose will be studied.

Researcher(s)

• Promoter: Van de Heyning Paul
• Co-promoter: Braem Marc
• Co-promoter: Vanderveken Olivier
• Fellow: Dieltjens Marijke

Research team(s)

• Translational Neurosciences (TNW)

Project type(s)

• Research Project