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Circadian changes in the hemostatic system in healthy men and patients with cardiovascular diseases

Piotr Chrusciel1, Aleksander Goch, Maciej Banach

  • 1Department of Cardiology and Cardiac Surgery, Military University Hospital No. 10 with a Polyclinic in Bydgoszcz, Bydgoszcz, Poland.

Medical Science Monitor : International Medical Journal of Experimental and Clinical Research
|October 1, 2009
PubMed

Insights

Circadian rhythms significantly impact hemostasis, increasing cardiovascular event risk in the morning. These daily variations in blood clotting factors and platelet activity are crucial for understanding morning heart attack and stroke incidence.

Area of Science:

  • Circadian Biology
  • Hemostasis and Thrombosis
  • Cardiovascular Medicine

Background:

  • Cardiovascular events exhibit a pronounced morning peak, potentially linked to circadian variations in hemostasis.
  • Daily fluctuations in von Willebrand factor (vWF), platelet count, and platelet aggregability are observed.
  • Coagulation and fibrinolysis markers show distinct 24-hour patterns, influencing morning cardiovascular risk.

Purpose of the Study:

  • To review the circadian rhythms of key hemostatic components.
  • To explore the relationship between daily hemostatic changes and the morning incidence of cardiovascular events.
  • To highlight alterations in circadian hemostasis patterns in individuals with health issues.

Main Methods:

  • Systematic review of existing literature on circadian variations in hemostasis.
  • Analysis of 24-hour periodicity in endothelium, platelets, coagulation, and fibrinolysis.
  • Comparison of circadian hemostatic patterns in healthy subjects versus those with health problems.

Main Results:

  • Circadian variability noted in vWF, platelet number (peak afternoon), and platelet aggregability (peak morning).
  • Elevated morning levels of coagulation markers (fragment 1+2, factor VIIa, fibrinogen) and PAI-1 activity.
  • Coagulation inhibitors (protein C, antithrombin III, TFPI) show peak activity in the morning; fibrinolytic activators lack periodicity.

Conclusions:

  • Circadian changes in the hemostatic system, particularly morning increases in prothrombotic factors, contribute to elevated cardiovascular event risk.
  • Disrupted circadian hemostasis patterns in unhealthy individuals may exacerbate cardiovascular risk.
  • Understanding these diurnal rhythms is vital for cardiovascular event prevention strategies.

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