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Published on: June 18, 2021
Chronobiological Patterns of Aneurysmal Subarachnoid Hemorrhage in Central China
Yuehui Wu1,2, Nan Tang1, Liangtao Xia3
1Department of Neurosurgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, CN.
Insights
Aneurysmal subarachnoid hemorrhage (aSAH) shows clear seasonal and daily patterns in China, with higher incidence in winter and specific daily peaks. Chronobiological variations exist across different patient groups.
Area of Science:
- Cerebrovascular disease research
- Chronobiology
- Epidemiology
Background:
- Aneurysmal subarachnoid hemorrhage (aSAH) is a critical, often fatal cerebrovascular event.
- Global understanding of aSAH chronobiological patterns remains limited.
- This study investigates seasonal, monthly, weekly, and circadian aSAH distributions.
Purpose of the Study:
- To clarify the chronobiological patterns of aSAH in central China.
- To identify seasonal, monthly, weekly, and circadian variations in aSAH onset.
- To explore how patient demographics and aneurysm characteristics influence these patterns.
Main Methods:
- Retrospective analysis of 1469 aSAH patient medical records.
- Chi-squared goodness-of-fit test for seasonal and weekly distributions.
- Fourier models to analyze monthly and circadian rhythmicity.
- Subgroup analyses based on age, gender, hypertension, and aneurysm details.
Main Results:
- Significantly higher aSAH incidence in winter and January/December; lower in summer and July.
- No significant weekly variation in aSAH onset.
- Significant circadian pattern with morning (8:00) and late afternoon (16:00-20:00) peaks.
- Circadian rhythmicity differed across age, gender, and aneurysm location subgroups.
Conclusions:
- aSAH occurrence demonstrates significant circannual and circadian patterns in the Chinese population.
- Chronobiological patterns of aSAH vary based on patient age, gender, and aneurysm location.
Background:
Aneurysmal subarachnoid hemorrhage (aSAH) is an acute and sometimes fatal cerebrovascular disease. The chronobiological patterns of aSAH are still unclear worldwide. This 15-year time-series study aims to clarify the chronobiological patterns including seasonal, monthly, weekly, and circadian distributions of aSAH.
Methods:
We retrospectively analyzed the medical records of aSAH patients in central China. To investigate seasonal and weekly distributions, we used the χ2 goodness-of-fit test to analyze the uniformity of the onset time. To explore monthly and circadian distributions, we established Fourier models to show the rhythmicity in chronobiological patterns. Subgroup analyses were conducted to assess the impact of age, gender, hypertension statuses, and aneurysmal characteristics (number, size, and location) on the chronobiological patterns of aSAH.
Results:
A total of 1469 patients with aSAH were recruited in the study. The seasonal and monthly distribution exhibited significantly higher incidence in winter and January/December and lower incidence in summer and July. The weekly distribution of aSAH onset showed no significant uneven variation. The circadian distribution of aSAH exhibited a significant pattern (p = 0.0145), with a morning peak around 8:00, and a late afternoon peak at 16:00-20.00. The circadian rhythmicity varied in subgroups of different ages, genders, and aneurysmal locations.
Conclusion:
The occurrence of aSAH exhibits significant circannual and circadian patterns among the Chinese population. Patients with aSAH of different ages, genders, and aneurysmal locations would present different chronobiological patterns.
