Postural hemodynamic parameters in older persons have a seasonal dependency : A pilot study

Area of Science:

• Cardiovascular Physiology
• Seasonal Variations in Health
• Geriatric Medicine

Background:

• Blood pressure regulation exhibits known seasonal variations.
• The cardiovascular system's response to postural changes in stroke patients across seasons remains understudied.

Purpose of the Study:

• To investigate seasonal influences on hemodynamic responses and heart rate variability during a sit-to-stand test in stroke patients and controls.
• To compare the effects of cold and warm seasons on cardiovascular adjustments to orthostatic stress.

Main Methods:

• Assessed hemodynamic responses (SBP, DBP, MBP, HR) and heart rate variability (HRV) during a 5-minute sitting to 5-minute standing test.
• Monitored beat-to-beat cardiovascular parameters in stroke patients and a control group across two distinct seasons (cold and warm).

Main Results:

• In colder months, both groups showed higher sitting baseline diastolic blood pressure (DBP) and mean blood pressure (MBP).
• Stroke patients exhibited lower stroke index (SI) in colder months during sitting.
• A significant decrease in systolic blood pressure (SBP) and DBP was observed in warmer months post-standing for non-stroke participants.

Conclusions:

• Elderly individuals, with or without stroke, exhibit a more pronounced blood pressure drop in response to orthostatic stress during warmer seasons.
• Seasonal temperature significantly influences the cardiovascular system's adaptation to postural changes in the elderly population.