[Circadian rhythm and lacunar syndromes]

Area of Science:

• Neurology
• Circadian Biology
• Stroke Medicine

Background:

• Limited understanding exists regarding the influence of circadian rhythms on the onset of lacunar syndromes.
• Investigating the temporal patterns of lacunar infarcts is crucial for understanding stroke mechanisms.

Purpose of the Study:

• To investigate the relationship between circadian rhythm and the onset of lacunar syndromes.
• To compare the onset times and clinical characteristics of lacunar infarcts (LI) versus non-infarct lacunar syndromes.
• To determine if the time of day influences the volume of brain injury in LI.

Main Methods:

• Prospective clinical analysis of 181 patients with LI and 47 with non-infarct lacunar syndromes.
• Recording the exact onset time of symptoms for each patient across four 6-hour intervals.
• Measuring infarct volume using computer analysis and comparing injury size based on onset time.

Main Results:

• 32.5% of LI cases began during nocturnal sleep, while 67.5% occurred during waking hours.
• Morning onset was significantly more frequent in cerebral hemorrhage-related lacunar syndromes (55.5%) than in LI (24.5%).
• LI with morning onset exhibited significantly larger infarct volumes (2,574 mm3) compared to afternoon (1,678 mm3) or night (1,328 mm3) onsets.

Conclusions:

• Approximately one-third of patients with lacunar infarcts experience symptom onset during sleep.
• The circadian timing of lacunar infarct onset, particularly in the morning, correlates with increased brain injury size.