The Interplay between Obstructive Sleep Apnea, Chronic Obstructive Pulmonary Disease, and Congestive Heart Failure: Time to Collectively Refer to Them as Triple Overlap Syndrome?

Big data approaches for novel mechanistic insights on sleep and circadian rhythms: a workshop summary

The National Center on Sleep Disorders Research of the National Heart, Lung, and Blood Institute at the National Institutes of Health hosted a 2-day virtual workshop titled Big Data Approaches for Novel Mechanistic Insights on Disorders of Sleep and Circadian Rhythms on May 2nd and 3rd, 2024. The goals of this workshop were to establish a comprehensive understanding of the current state of sleep and circadian rhythm disorders research to identify opportunities to advance the field by using approaches based on artificial intelligence and machine learning. The workshop showcased rapidly developing technologies for sensitive and comprehensive remote analysis of sleep and its disorders that can account for physiological, environmental, and social influences, potentially leading to novel insights on long-term health consequences of sleep disorders and disparities of these health problems in specific populations.

A Foundation Model for Sleep-Based Risk Stratification and Clinical Outcomes

Clinical diagnosis of sleep disorders, which are recognized contributors to morbidity and mortality, often relies on polysomnography (PSG) data. However, the vast physiologic data collected during PSG is underutilized, presenting a key opportunity to enhance characterization of sleep dysfunction and predict clinical outcomes. We introduce a sleep foundation model that uniquely integrates PSG time-series signals and electronic medical record data. Using a diverse dataset (n=10,000; mean observation period 14.5±7.1 years), our transformer-based model generates data-driven representations of latent physiological patterns. When clustered, we identified subpopulations with differential health trajectories. The highest risk-group exhibited strong correlations with all-cause mortality (unadjusted hazard ratio [HR] 4.83, 95% confidence interval [CI] 3.60-6.50, p<0.001) as well as cardiovascular outcomes and neurological outcomes, even after accounting for traditional measures. External validation in a National Sleep Research Resource cohort confirmed findings. We created a novel, clinically applicable framework leveraging information-dense PSG data to inform risk stratification and predict health outcomes beyond traditional methods.

Advancements in the neurocirculatory reflex response to hypoxia

Hypoxia is a pivotal factor in the pathophysiology of various clinical conditions, including obstructive sleep apnea, which has a strong association with cardiovascular diseases like hypertension, posing significant health risks. Although the precise mechanisms linking hypoxemia-associated clinical conditions with hypertension remains incompletely understood, compelling evidence suggests that hypoxia induces plasticity of the neurocirculatory control system. Despite variations in experimental designs and the severity, frequency, and duration of hypoxia exposure, evidence from animal and human models consistently demonstrates the robust effects of hypoxemia in triggering reflex-mediated sympathetic activation. Both acute and chronic hypoxia alters neurocirculatory regulation and, in some circumstances, leads to sympathetic outflow and elevated blood pressures that persist beyond the hypoxic stimulus. Dysregulation of autonomic control could lead to adverse cardiovascular outcomes and increase the risk of developing hypertension.

Exploring Current Concepts and Challenges in the Identification and Management of Early-Stage COPD

The need to improve health outcomes, as well as disease prognosis, has led clinicians and researchers to propose new ways of identifying COPD in its earliest forms. This initiative is based on the hypothesis that an earlier intervention would have a greater prognostic impact. However, the operational definition of a patient in the initial stages of the disease is complex, and there is still no unanimously accepted definition. GOLD has recently proposed different concepts to identify COPD in its early stages, such as COPD in young people or COPD with mild functional impairment. In addition, GOLD proposes two other concepts, called pre-COPD (symptomatic non-obstructive patients) and PRISm (preserved ratio with impaired spirometry), which aim to identify the patient at risk of developing this chronic airflow obstruction. However, despite the attractiveness of these concepts, none have been taken up universally by the medical community. A universally accepted identification of how to define COPD in its early stages is necessary as a preliminary step in order to design clinical trials to find out the best way to treat these patients. This review deals with these concepts of COPD at the onset of the disease, highlighting their importance and the problems involved in identifying them as therapeutic targets in real clinical practice.