Sleep is such an essential part of human existence that we spend about a third of our lives doing it -- some more successfully than others. Sleep disorders afflict some 50-70 million people in the United States and are a major cause of disease and injury.
People who suffer from disturbed sleep have an increased risk of heart attack, stroke, hypertension, obesity, depression, and accidents. Nearly a fifth of all serious car crashes, in fact, are linked to sleeplessness.
Diagnosing sleep disorders is not necessarily easy. In standard "sleep studies," people spend one or more nights at hospitals or other inpatient centers, sleeping while sensors and electrodes attached to the head and torso record breathing, brain waves, heart rate, and other vital signs.
Now, a group of scientists in Israel and Germany has discovered a simple new way to monitor sleep and potentially diagnose sleep disorders just by recording someone's heart rate. Their method relies on using a mathematical technique to analyze these recordings and tease out information related to the synchronization between heartbeat and breathing, which might be a measure of fitness of the cardio-respiratory system.
Their work may one day help clinicians more easily diagnose sleep disorders and determine optimal treatments for people with congestive heart failure. Athletes might also be able analyze their own recordings to optimize workouts.
Conducted by researchers at Technische Universität Ilmenau in Germany, Bar-Ilan University in Ramat Gan, Israel, Martin-Luther-Universität Halle-Wittenberg in Germany, and Schlafmedizinisches Zentrum der Charité Berlin, the work appears in a special focus issue of the journal Chaos, which is published by the American Institute of Physics (AIP). The special issue is focused on nonlinear dynamics in cognitive and neural systems. It asks how chaos affects certain brain areas and presents interdisciplinary approaches to various problems in neuroscience -- including sleep disorders.
Monitoring the heartbeat provides information about breathing because the two physiological processes are weakly coupled. During inhalation, the heart beats faster. During exhalation, the heart slows down. These effects are seen during sleep as well. Moreover, the heart rate and breathing rate also change across certain stages of sleep. They are faster and fluctuate more during rapid eye movement (REM) sleep than they do during deep sleep, for instance.
In their new study, the Israeli and German scientists showed that the synchronization between the heartbeat and breathing pattern is significantly enhanced during certain stages of sleep. By mathematically analyzing someone's heart rate throughout the night, they could gain information on that person's breathing and sleep stage.
They looked at data from the European project SIESTA, which keeps a database of sleep data recorded in seven countries from 295 people -- about half of whom have sleep disorders. Subjects of this study spent two nights in sleep laboratories, slumbering while electrodes connected to their heads and torsos monitored things like brain and muscle activity, heart rate, and eye movement. This collection of physiological data is what normally enables doctors to reconstruct the phases of sleep and diagnose sleep disorders.
The Israeli and German scientists analyzed just the heart data for the 150 people in the SIESTA study who have no known sleep disorders. They then used the heartbeats to reconstruct the breathing patterns, and they showed that these reconstructions accurately reflect the actual recorded breathing data collected in sleep labs. Moreover, looking at the synchronization between heartbeat and breathing, the group could show that there is a significant relationship between sleep stages and cardio-respiratory synchronization patterns, i.e., heartbeat and breathing mostly synchronize during non-REM sleep (light and deep sleep), and cardio-respiratory synchronization is almost absent during REM sleep.
Next they plan to extend their study to people with sleep disorders to determine whether their technique can accurately diagnose these disorders. Analyzing the heartbeat using their technique may also reveal information about cardiorespiratory capacity, which may lead to diagnostic markers of cardiac diseases and ways to determine optimal treatments for people with congestive heart failure. Monitoring cardiorespiratory capacity may also help atheletes optimize workout routines.
Jason Bardi | EurekAlert!
Further reports about: > Brain waves > Depression > Heart Attack > REM sleep > SIESTA > accidents > brain area > cardio-respiratory system > congestive heart failure > eye movement > heart failure > heart rate > hypertension > obesity > serious car crashes > sleep disorders > sleep studies > sleeplessness > stroke > vital signs
Using fragment-based approaches to discover new antibiotics
21.06.2018 | SLAS (Society for Laboratory Automation and Screening)
Scientists learn more about how gene linked to autism affects brain
19.06.2018 | Cincinnati Children's Hospital Medical Center
In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.
Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
22.06.2018 | Materials Sciences
22.06.2018 | Earth Sciences
22.06.2018 | Life Sciences