St. Vincent's University Hospital / University College Dublin Sleep Apnea Database

@article{pollard_physionet_2026, title = {{PhysioNet} as a global platform for biomedical research}, volume = {1}, issn = {3005-0693}, url = {https://doi.org/10.1038/s44360-026-00096-z}, doi = {10.1038/s44360-026-00096-z}, abstract = {Twenty-five years after its first public repository was established, the PhysioNet resource for biomedical and clinical data has enabled tens of thousands of research papers. Further efforts are ongoing to advance secure data sharing, community engagement and scalable research infrastructure.}, number = {8}, journal = {Nature Health}, author = {Pollard, Tom and Moody, Benjamin E. and Lehman, Li-wei H. and Gow, Brian J. and Fernandes, Chrystinne and Xie, Chen and Johnson, Alistair and Mark, Roger G. and Heldt, Thomas}, month = aug, year = {2026}, pages = {792--795},}

Abstract

This database contains 25 full overnight polysomnograms with simultaneous three-channel Holter ECG, from adult subjects with suspected sleep-disordered breathing. A revised version of this database was posted on 1 September 2011.

Subjects

Subjects were randomly selected over a 6-month period (September 02 to February 03) from patients referred to the Sleep Disorders Clinic at St Vincent's University Hospital, Dublin, for possible diagnosis of obstructive sleep apnea, central sleep apnea or primary snoring. Subjects had to be above 18 years of age, with no known cardiac disease, autonomic dysfunction, and not on medication known to interfere with heart rate. Twenty-five subjects (21M, 4F) were selected (age: 50 ± 10 years, range 28-68 years; BMI: 31.6 ± 4.0 kg/m², range 25.1-42.5 kg/m²; AHI: 24.1 ± 20.3, range 1.7-90.9). Details are shown in SubjectDetails.xls.)

Signals

Polysomnograms were obtained using the Jaeger-Toennies system (Erich Jaeger GmbH, Germany). Signals recorded were: EEG (C3-A2), EEG (C4-A1), left EOG, right EOG, submental EMG, ECG (modified lead V2), oro-nasal airflow (thermistor), ribcage movements, abdomen movements (uncalibrated strain gauges), oxygen saturation (finger pulse oximeter), snoring (tracheal microphone) and body position. The files named with .rec suffixes contain these signals in EDF format.

Three-channel Holter ECGs (V5, CC5, V5R) were recorded using a Reynolds Lifecard CF system (Reynolds Medical, UK); the files named with _lifecard.edf suffixes contain these ECG signals in EDF format. The recording dates and times are not available. In record ucddb002, only two distinct ECG signals were recorded; the second ECG signal was also used as the third signal.

Annotations

Sleep stages were scored by an experienced sleep technologist according to standard Rechtschaffen and Kales rules (see the _stage.txt files). Annotations/meanings in these files are:

• 0 - Wake
• 1 - REM
• 2 - Stage 1
• 3 - Stage 2
• 4 - Stage 3
• 5 - Stage 4
• 6 - Artifact
• 7 - Indeterminate

Onset time and duration of respiratory events (obstructive, central, mixed apneas and hypopneas, and periodic breathing episodes) were annotated by the same sleep technologist (see the _respevt.txt files). Terms used in these files include:

• 1st column - Time of occurrence (time of day)
• 2nd column
  • HYP - Hypopnea
  • C - Central
  • O - Obstructive
  • M - Mixed
• 3rd column - Periodic breathing (PB)/ Cheynes-Stokes (CS)
• 9th & 10th columns - Bradycardia/ Tachycardia

Acknowledgments

These recordings were collected at St. Vincent's University Hospital Sleep Disorders Clinic, under the direction of Prof. Walter McNicholas. Dr. Liam Doherty, Dr. Silke Ryan, and Dr. John Garvey collected and assembled the clinical and demographic information, and Ms. Patricia Boyle was responsible for polysomnogram scoring and annotation. Eric Chua was responsible for de-identification and electronic archiving of records.

Contact information

Conor Heneghan, PhD
School of Electrical, Electronic and Mechanical Engineering
University College Dublin
Belfield
Dublin 4
Ireland
Email: conor.heneghan at ucd dot ie

Technical contact: Eric C.-P. Chua (eric dot chua dot 2 at gmail dot com)

Cited by

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• Polysomnography Dataset for Sleep Analysis in Ischemic Stroke Patients
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View all 19 publications

Citation data from OpenAlex. Papers that use the project without citing it may be missing.