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A Magnetic Resonance Imaging Protocol for Stroke Onset Time Estimation in Permanent Cerebral Ischemia
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A Magnetic Resonance Imaging Protocol for Stroke Onset Time Estimation in Permanent Cerebral Ischemia

Published on: September 16, 2017

The related causes in very early morning onset of stroke

Abdulkadir Kocer1, Atilla Ilhan, Nurhan Ince

  • 1Department of Neurology, Dr. Lütfi Kýrdar Teaching Hospital, Istanbul, Turkey. abdulkadirkocer@yahoo.com

Progress in Neuro-Psychopharmacology & Biological Psychiatry
|July 16, 2005
PubMed

Insights

Early awakening increases cerebrovascular disease (CVD) risk, particularly between 3-6 AM. This early morning stroke risk, influenced by weather and physiology, affects nearly one-third of all stroke cases.

Area of Science:

  • Neurology
  • Epidemiology
  • Circadian Biology

Background:

  • Cerebrovascular disease (CVD) represents a significant global health burden.
  • The circadian pattern of stroke onset, particularly the influence of early morning hours, requires further investigation.
  • Understanding temporal risk factors is crucial for effective prevention strategies.

Purpose of the Study:

  • To investigate the influence of early awakening and related factors on the onset time of cerebrovascular disease (CVD).
  • To analyze the circadian pattern of stroke occurrence in a large patient cohort.
  • To identify specific time windows associated with increased stroke risk.

Main Methods:

  • Retrospective analysis of 1199 stroke patients with known onset times from three reference hospitals.
  • Categorization of stroke types: ischemic stroke (cerebral infarction), intracerebral hemorrhage (CH), and subarachnoid hemorrhage (SAH).
  • Statistical analysis of demographic, medical, and pathophysiological factors related to stroke onset timing.

Main Results:

  • The highest incidence of strokes (32.5%) occurred between 03:00 and 06:00 a.m.
  • Nearly half of all analyzed strokes happened in the early to mid-morning hours.
  • A significantly higher risk of stroke was observed between 03:00 a.m. and 06:00 a.m. compared to nighttime (21:00 p.m. to midnight).
  • Approximately one in three strokes, including ischemic, hemorrhagic, and subarachnoid types, were attributable to this early morning peak.

Conclusions:

  • Early morning hours (03:00-06:00 a.m.) are a period of significantly elevated risk for cerebrovascular events.
  • The observed early morning excess in stroke incidence may be linked to factors such as cold weather, religious practices, and physiological mechanisms.
  • Further research is warranted to elucidate the precise mechanisms underlying the circadian variation in stroke onset.

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