Integrated Yoga/Meditation-Based Therapy for Complex Sleep Apnea

Awardee Recipient

  • Amit Anand, MD

    Amit Anand, MD

    Faculty Member and Instructor in Medicine

    Beth Israel Deaconess Medical Center and Harvard Medical School

    Amit N. Anand, MD is a faculty member in the Division of Pulmonary, Critical Care and Sleep Medicine at Beth Israel Deaconess Medical Center and an Instructor in Medicine at Harvard Medical School. He received his Bachelor in Medicine, Bachelor...

Award

  • 2016 - Pilot Grant

Specific Aims

The respiratory chemoreflex is central to the pathophysiology of obstructive sleep apnea, periodic breathing at high altitude, congestive heart failure, hypoventilation syndromes and chronic obstructive lung disease. Activation of the respiratory chemoreflex in these chronic conditions also causes sustained increases in sympathetic drive. Excessive sympathetic activation has a range of adverse consequences on health, including hypertension, anxiety, impaired glucose handling, cardiac arrhythmogenesis, endothelial dysfunction, and induction / progression of myocardial dysfunction.

We propose a novel central hypothesis – that a persistently hyper-responsive respiratory chemoreflex causes 1) a wide variety of sleep apnea syndromes, including syndromes currently termed ‘complex sleep apnea’, ‘idiopathic central sleep apnea’ (ICSA), heart failure related CSA, a subset of ‘obstructive sleep apnea’, and high-altitude sleep apnea (High Chemosensitivity Sleep Apnea, HCSA); 2) pervasive multi system effects of sustained day and night chemoreflex activation. HCSA, we propose, is the sleep state expression of a more generalized “chemoreflex syndrome”.

The core pathology in HCSA is an enhanced hypercapnic ventilatory response. During sleep, this high respiratory control system “gain” causes sleep apnea during non-rapid eye movement (NREM) sleep. Thus one biomarker of HCSA is the occurrence of non-REM dominant sleep apnea identified during conventional polysomnography.

Continuous positive airway pressure (CPAP) is not a fully effective therapy for HCSA – sleep fragmentation, periodic breathing or obstructive events persist in NREM but not REM sleep, while central apneas tend to decrease with time on treatment. We have developed an improved treatment for HSCA that minimizes CO2 fluctuations during CPAP. This treatment uses a non-vented mask and adjunctive dead space, and it can improve the clinical management of NREM-dominant sleep apnea. However, residual sleep fragmentation and sleep apnea (readily quantifiable on the high resolution flow data available in current generation CPAP devices) is common. This results in persistently unrefreshing sleep, fatigue, and we suspect, non-dipping of blood pressure.

Meditation and certain yogic breathing practices have profound effects on the autonomic nervous system, including sympathetic drive and vagal tone. The pervasive effects of these maneuvers is demonstrated by functional magnetic imaging studies, showing modulation of activity in the central autonomic network, including the insula, the anterior cingulate and the ventromedial prefrontal cortex. Meditation and slow breathing approaches also reduce the slope of the hypercapnic ventilatory response, of key importance in our thinking.

Several innovations enable our proposal. Frist, current CPAP technology allows easy tracking of actual breathing even on a nightly basis, transmitted wirelessly via Wi-Fi modems – the dynamics and time constants of the effects of therapy are readily quantified. Second, technology developed at the Beth Israel Deaconess Medical Center (BIDMC) by co-investigator Dr. Thomas used ECG-based analysis of cardiopulmonary coupling, providing unique measures of sleep quality and stability. The software is implemented in a FDA approved wearable device (M1, www.slepeimage.com) that we will use to track the efficacy of our integrated breathing modulation approach, which we term IYBAM (pronounced “e-bam”, Integrated Yogic Breathing and Meditation. Finally, we introduce smartphone-based cognitive tracking to sleep apnea medicine.

Hypothesis 1: IYBAM reduces the slope of the hypercapnic ventilatory response (HCVR) in complex apnea.
Aim 1: Assess HCVR pre and post a 60-day IYBAM vs. sham protocol, in compliant patients with residual apnea on therapy flow waveforms.

Hypothesis 2: IYBAM increases stable breathing and subjective/objective sleep quality in complex apnea.
Aim 2: Assess home therapy respiratory waveforms including quantifying stable breathing, and high frequency cardiopulmonary coupling, and subjective sleep quality, pre/post 60-days of IYBAM.

Hypothesis 3: IYBAM improve nocturnal blood pressure in complex apnea.
Aim 3: Measure ambulatory BP pre/post 60 days of IYBAM.

Hypothesis 4: IYBAM improves vigilance, attention, and information processing speed
Aim 4: Assess, using the Defense Automated Neurobehavioral Assessment (DANA) smartphone-based cognition App, the impact of IYBAM on cognitive function.

Successful completion of the pilot project will provide key new information, understanding and delineate appropriate targets for further investigating the effect of Yoga and Meditation practices on sleep, sleep- respiration, and sleep/global autonomic regulation.

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