Diurnal Variation of and Activity during the Onset of Stroke

Abstract

The diurnal variation in the onset of stroke was examined in 557 consecutive patients aged over 70 years. These included 194 patients with subarachnoid hemorrhage, 118 with intracerebral hemorrhage, and 245 with thromboembolic cerebral infarction. All three types of strokes exhibited a peak incidence between 1000 and 1200 hours. Intracerebral hemorrhages occurred less frequently between 0400 and 0600 hours, but there were no differences between the groups for the other time periods. There was no difference in the time of onset of stroke between normotensive and treated or untreated hypertensive patients. There were more untreated hypertensive patients in the intracerebral hemorrhage group than in the other stroke type groups. Subarachnoid hemorrhage occurred more frequently in the lavatory and during sexual and sporting activity. Intracerebral hemorrhage occurred more commonly during driving or the consumption of alcohol. Cerebral infarction occurred more frequently during sleep or was noticed on waking. No differences were found for the other activities examined. The relationship between diurnal variation in stroke and the known variation in blood pressure is discussed.

Potential Triggering Factors of Intracerebral Hemorrhage

“…Since much time is normally spent sleeping or resting, ICH can be considered infrequent in these circumstances. This is in line with results of several studies in the circadian distribution of ICH, where a marked reduction in the incidence of ICH was found at night when people are usually sleeping [5, 10, 11]. However, the distribution of ICH was greatly influenced by the cause of bleeding.…”

“…An association has been suggested between the onset of SAH and strenuous physical activity, sexual intercourse, defecation/micturition and recent drinking of alcohol [10, 16]. The circumstances of onset of ICH and ischemic stroke are largely unknown.…”

“…The circumstances of onset of ICH and ischemic stroke are largely unknown. Apart from anecdotal observations associating onset of ICH with sexual activity [39], the dentist’s chair [40]or delivery [41]there have been few reports on the subject [10, 42]. …”

“…BP has a seasonal pattern related to temperature with higher values in winter and lower values in summer [1], and a circadian rhythm related to the sleep-wake cycle with lower values during rest/sleep and inactivity, a rise on awakening and higher values during the rest of the day [2]. The winter and morning rises in BP have been invoked to explain the increased number of vascular events in the cold months [3, 4, 5, 6, 7]and in the morning waking hours [5, 8, 9, 10, 11, 12, 13, 14]. …”

“…Unlike cardiovascular diseases [17, 18, 19, 20, 21]and aneurysmal subarachnoid hemorrhage (SAH) [10, 16], the circumstances surrounding the onset of ischemic stroke or intracerebral hemorrhage (ICH) and potential triggering factors are poorly documented [10]. …”