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Circadian systolic and diastolic differences (CSDD) and circadian modulation of 1.7-h ultradians
Chronobiologia
|January 1, 1987
Insights
Ambulatory blood pressure monitoring reveals significant overlap between systolic and diastolic readings in most cases. An ultradian rhythm component, most prominent during sleep, influences these blood pressure patterns.
Area of Science:
- Cardiology
- Chronobiology
- Physiology
Background:
- Ambulatory blood pressure monitoring (ABPM) is crucial for assessing cardiovascular health.
- Understanding blood pressure variability, including systolic and diastolic overlap, is key to accurate diagnosis.
- Circadian and ultradian rhythms significantly influence physiological processes like blood pressure.
Purpose of the Study:
- To analyze the extent of overlap between systolic and diastolic pressures in 24-hour ABPM.
- To investigate the influence of ultradian rhythms on blood pressure patterns.
- To determine the relationship between ultradian rhythm prominence and circadian stage, particularly sleep.
Main Methods:
- Analysis of 24-hour ambulatory blood pressure monitoring data.
- Calculation of overlap between lowest systolic and highest diastolic pressures.
- Time-series analysis to identify and quantify ultradian rhythm components (around 1.7-hour period).
- Assessment of ultradian component prominence across different circadian stages, including sleep.
Main Results:
- Over 90% of 24-hour ABPM profiles showed overlap between lowest systolic and highest diastolic pressures.
- Approximately 75% of cases exhibited overlap when considering 90% ranges of pressure values.
- The 1.7-hour ultradian component's prominence varied significantly with circadian stage.
- This ultradian component was most pronounced during mid-sleep.
Conclusions:
- Significant overlap between systolic and diastolic blood pressure is a common finding in ABPM.
- Ultradian rhythms play a notable role in blood pressure variability, especially during sleep.
- Further research into these rhythmic patterns may enhance cardiovascular risk assessment.
Abstract:
In 24-h ambulatory blood pressure profiles there is overlap between the lowest systolic and the highest diastolic pressure in over 90% of the cases. An overlap is observed in about 75% of the cases when considering 90% ranges. The prominence of the 1.7-h ultradian component varies as a function of circadian stage and is found to be most prominent around mid-sleep.
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