Epidemiological chronorisk of stroke

Area of Science:

• Neurology
• Chronobiology
• Epidemiology

Background:

• Stroke is a leading cause of death and disability worldwide.
• Understanding temporal patterns in stroke occurrence may inform prevention and treatment strategies.
• Previous research has suggested potential daily and seasonal variations in stroke incidence.

Purpose of the Study:

• To investigate the circadian, circaseptan, and circannual rhythms in the onset of symptoms for 667 out-of-hospital stroke cases.
• To differentiate temporal patterns between cerebral infarction and cerebral hemorrhage.
• To examine potential sex-based differences in stroke occurrence timing.

Main Methods:

• Retrospective analysis of 667 stroke cases (508 cerebral infarction, 159 cerebral hemorrhage) from 1971-1988.
• Application of the single cosinor method to analyze temporal patterns.
• Statistical comparison of rhythmicity between stroke subtypes and sexes.

Main Results:

• Significant circadian, circaseptan, and circannual rhythms were observed in overall stroke occurrence.
• Peak stroke incidence occurred in morning hours, on weekends, and during winter.
• Cerebral hemorrhages lacked circadian rhythmicity but showed circaseptan and circannual patterns; cerebral infarctions exhibited all three rhythms. No sex differences were found.

Conclusions:

• Stroke occurrence exhibits distinct temporal patterns, with specific variations between cerebral infarction and hemorrhage.
• Understanding these chronobiological patterns is crucial for advancing stroke pathogenesis research and optimizing treatment timing.
• These findings highlight the importance of considering daily, weekly, and seasonal factors in stroke management.