Scientists from Beth Israel Deaconess Medical Center had developed a novel way to assess sleep and diagnose sleep related problems in a very cost effective manner. They had reported in the journal Sleep that it is possible to use the information from the heartbeats to develop the procedures that will successfully measure the quality of sleep of the problems associated with it.
Known as a "sleep spectrogram," the novel graph is based on data obtained solely from a simple electrocardiogram (ECG). The spectrogram is described in a study in the Sept. 1 issue of the medical journal Sleep, which currently appears on-line.
The new study, the researchers had identified two distinct types of behavior exhibited throughout the course of a person's sleep, the first being stable and restful, the second being unstable and aroused. The results show that conventional approaches to categorize non-REM (non-rapid-eye-movement) sleep into grades of depth do not capture this potentially important dimension.
Among healthy adults, physiological behaviors will show relatively abrupt shifts - a occurring over minutes - between both stable and unstable sleep, but the stable stage clearly dominates. But in a variety of disease states, the spectrogram shows that an unstable sleep pattern is predominant, and among patients with severe cases of sleep apnea, virtually all of the patient's non-REM sleep is unstable.
The creation of the spectrogram could serve as an important complement to traditional sleep staging, which shows cycles of rapid eye movement (REM) and non-REM sleep and is obtained through polysomnography, a series of measurements that require the use an electroencephalogram (EEG) to record patients' brain waves.