Abrupt Shift of the Pattern of Diurnal Variation in Stroke Onset With Daylight Saving Time Transitions

Abstract

Background-Stroke onset shows a pattern of diurnal variation, with a peak in morning hours. Rhythmic changes in blood pressure, hormones, and other parameters have been suggested as underlying mechanisms, but exogenous factors such as increasing physical activity after awakening may also be of relevance. To characterize the impact of external clock changes on the rhythmic variation in stroke onset, this parameter was recorded in patients during transition periods into and out of Daylight Saving Time (DST). Methods and Results-The present study was based on a prospective stroke registry in Germany that contains time points of stroke onset from 44 251 patients admitted between 2000 and 2005. To achieve a uniform timeline, time points of stroke onset were set back from Central European Summer Time (CEST) to Central European Time (CET) for patients admitted during DST periods. Compared with the last week before the clock change, transition to or from DST resulted in an immediate shift of stroke onset time points within the first week after the clock change in reference to the uniform timeline (transition from CET to CEST Ϫ60 minutes for the time points in both the 25th and 50th percentiles of the diurnal pattern, PϽ0.001; transition from CEST to CET ϩ60 minutes for the time points in both the 25th and 50th percentiles, PϽ0.001; patients pooled on a weekly basis). A significant shift was already present the first and second day after the transitions (ie, Monday and Tuesday). Conclusions-Transition to or from DST is coupled with an immediate shift in the time pattern of stroke onset. This strengthens the idea that exogenous factors associated with awakening are important determinants of the pattern of diurnal variation of stroke onset, because entrainment of the human circadian clock within hours is unlikely.

Circadian misalignment and health

“…(Janszky et al, 2012; Janszky & Ljung, 2008). This relationship has also been documented in stroke (Foerch, Korf, Steinmetz, & Sitzer, 2008). Fewer studies have focused on the psychiatric effects of daylight saving time.…”

Diurnal Variation in Onset of Hemorrhagic Stroke Is Independent of Risk Factor Status: Takashima Stroke Registry

“…The physiological processes related to these physical activity components may trigger the acute event. In a recent study, it was observed that transition to or out from daylight saving time is coupled with an immediate shift of the time pattern of stroke onset [5] . This suggests an association between the exogenous factors associated with awakening and the diurnal pattern of stroke.…”

Circadian rhythm of stroke onset during the month of Ramadan

“…Exogenous factors associated with awakening are important determinants of the pattern of diurnal variation of stroke onset. A recent study demonstrated that transition into or out of DST is coupled with an immediate shift of the time pattern of stroke onset (16). An abrupt change in physical activity is not only a major determinant of the diurnal variation of blood pressure but also an important triggering factor for a cerebrovascular event (39).…”

“…The circadian pattern of onset is less certain for hemorrhagic stroke; however, a study noted significant increase in the time of onset of intracerebral hemorhage and subarachnoid hemorrhage between 8.00 and 16.00 h (15). Transition into or out of daylight saving time (DST) is coupled with an immediate shift of the time pattern of stroke onset (16).…”