As World Heart Day approaches, we are reminded of people who live with complex sleep disorders and how we can adequately address their unique needs. Through our research, we have learned that patients living with sleep disorders, such as narcolepsy and idiopathic hypersomnia, experience the effects of their conditions across many aspects of their lives, from their sleep health to overall well-being.
To commemorate this important awareness milestone, Jazz Pharmaceuticals’ own Kelvin Tan, MB BCh, MRCPCH, Senior Vice President, Chief Medical Officer, spoke with sleep specialist Logan Schneider, MD, Clinical Assistant Professor (affiliated) of Sleep Medicine, Stanford Sleep Center and Consultant Neurologist, Stanford/VA Alzheimer’s Center, about cardiovascular comorbidities associated with sleep disorders and what recent studies show about improving the overall health of people living with these disorders.
Kelvin Tan, MB BCh, MRCPCH, Senior Vice President, Chief Medical Officer at Jazz Pharmaceuticals: My Jazz colleagues and I are grounded in our long-standing, deep commitment to sleep patients. Part of that commitment is reflected in increased education and awareness around rare and complex disorders to help educate patients and physicians alike. To start off, could you tell us about narcolepsy and idiopathic hypersomnia?
Logan Schneider, MD, Clinical Assistant Professor (affiliated) of Sleep Medicine, Stanford Sleep Center and Consultant Neurologist, Stanford/VA Alzheimer’s Center: Narcolepsy and idiopathic hypersomnia are two distinct sleep disorders. Narcolepsy is a chronic, debilitating neurologic sleep disorder.1 Excessive daytime sleepiness (EDS) is the primary symptom of narcolepsy and is present in all people with the disorder.2 It is described as the inability to stay awake and alert during the day resulting in the irrepressible need to sleep or unplanned lapses into sleep or drowsiness, commonly referred to as “sleep attacks”.2,3,4 Additional key symptoms include, cataplexy, disrupted nighttime sleep, sleep-related hallucinations, and sleep paralysis.5 While all people with narcolepsy experience EDS, not all individuals with narcolepsy experience all five symptoms.3,6
In contrast, while patients with idiopathic hypersomnia also experience EDS, this debilitating sleep disorder goes beyond chronic sleepiness. People living with idiopathic hypersomnia experience a 24-hour disease with severe sleep inertia (or sleep drunkenness, which is a prolonged difficulty waking from sleep with frequent entries into sleep, confusion, and irritability), prolonged but non-restorative nighttime sleep, as well as, cognitive impairment often described as brain fog, and long and unrefreshing naps.2,7,8,9,10
In sum, although individuals with narcolepsy may experience “refreshed” after sleep, those with idiopathic hypersomnia often report that they never feel fully awake. Thus, even though both narcolepsy and idiopathic hypersomnia are considered sleep central disorders of hypersomnolence, there exists a vast spectrum of disease and variation in how their symptoms manifest among patients.
Kelvin: Yes, I am all too familiar with the distinctions between each disorder but despite their differences, our recent research has revealed that both disorders are associated with cardiovascular and cardiometabolic comorbidities. Could you talk about these studies and highlight some of the comorbidities?
Dr. Schneider: Two recent studies, “Cardiovascular Burden of Narcolepsy Disease (CV-BOND): A Real-World Evidence Study” and “Cardiovascular Burden of Patients Diagnosed With Idiopathic Hypersomnia: Real-World Idiopathic Hypersomnia Total Health Model (CV-RHYTHM)” have showed us that these two sleep disorders have in common—an increased prevalence of cardiovascular comorbidities, including heart failure and stroke.
The CV-BOND study findings, which were based upon a retrospective analysis of U.S. healthcare claims data, showed that individuals with narcolepsy are at an increased risk of developing new-onset cardiovascular events compared to individuals without narcolepsy. These included any stroke, cardiovascular disease and heart failure. In practice, this means that even if patients with narcolepsy did not present with cardiovascular diseases early on in their diagnosis, they had a higher rate of developing these complications later on as compared to patients without the sleep disorder.11
Similar findings were revealed as part of the CV-RHYTHM study, which compared cardiovascular comorbidities of people diagnosed with idiopathic hypersomnia to people without idiopathic hypersomnia based on administrative claims data. The study found that when compared to those without idiopathic hypersomnia, patients experienced a significantly higher prevalence of cardiovascular comorbidities, including cardiovascular disease, stroke, heart attacks and heart failure.12
While the exact reasoning for this increased risk is still not clearly understood, experts suspect that biological reasons and other variables, from sleep interruptions (which are known to impact heart health as it’s tied to nocturnal blood pressure) to lifestyle and dietary choices may be factors.13,14,15,16,17
Kelvin: What are the most important takeaways from the CV-BOND and CV-RHYTHM studies, and how can healthcare professionals implement them into their practice?
Dr. Schneider: Findings from both studies further cement that people with sleep disorders are more likely to have cardiovascular comorbidities when compared to their peers without sleep disorders. Narcolepsy and idiopathic hypersomnia are both chronic conditions that require lifelong treatment. Both patients and healthcare providers must bear this in mind as they navigate their lives and how best to manage the symptoms, respectively.
For patients, it is important to note that sodium is a modifiable risk factor for cardiovascular diseases. Thus, patients and their doctors working closely together to evaluate sodium intake is one way to help in taking the necessary steps to reduce the risk of developing cardiovascular comorbidities. Also, when discussing management plans with their doctor, patients should be sure to share their concerns regarding sodium intake, cardiovascular risk, and any other comorbidities.
For physicians, they must consider their patients’ holistic health when developing a management plan. Patient management plans should not only address the core symptoms of their sleep disorder but also the surrounding aspects of their lives. In order to choose the best management plan that will provide the highest quality of care, physicians should consider the patients’ lifestyle choices, all while keeping in mind any factors for increased risk of cardiovascular and cardiometabolic issues.
