Assessment of hypertension based on chronoengineering

Area of Science:

• Cardiovascular Physiology
• Biomedical Engineering
• Chronobiology

Background:

• Automatic ambulatory recording systems enhance blood pressure data collection and interpretation.
• Assessing circadian variability of human blood pressure requires specialized software modules.
• Understanding within-day blood pressure fluctuations is crucial for health assessment.

Purpose of the Study:

• To evaluate changes in blood pressure within a day using automatic monitoring.
• To develop a method for assessing circadian blood pressure variability and establishing health reference limits.
• To improve the accuracy of blood pressure diagnosis and treatment monitoring.

Main Methods:

• Analysis of 303 series of systolic and diastolic blood pressures and heart rates monitored automatically every 30 minutes for at least 48 hours.
• Application of least-squares rhythmometry to compute individual circadian rhythm parameters.
• Computation of a time-specified prediction region (paradesm) for amplitude-acrophase pairs and time-specified tolerance limits for blood pressure and heart rate.

Main Results:

• Established reference limits for circadian amplitude of blood pressure, identifying amplitude-hypertension.
• Computed time-specified tolerance limits for blood pressure and heart rate in clinically healthy individuals.
• Demonstrated that the combined hardware-software method allows assessment of rhythmic changes and interpretation of single values.

Conclusions:

• The developed system facilitates objective definition of health and screening/diagnosis of diseases.
• Reference limits derived from this method can eliminate false positive and negative diagnoses.
• The method provides a tool for gauging treatment response and interpreting single blood pressure values accurately.