Chronobiological variations of acute aortic dissection in a Northwest Chinese population

Background: The prevalence of acute aortic dissection (AAD) has been gradually increasing in recent years. This study aimed to investigate the circadian variations of AAD onset in a northwest Chinese population and provide scientific insights for AAD prevention.

Methods: The clinical data of 1,145 AAD patients admitted to our hospital between January 2010 and December 2020 were retrospectively collected, and the periodic features of AAD were analyzed.

Results: Stanford type A and type B AAD were present in 58.43% (669 cases) and 41.57% (476 cases) of the patients, respectively. The incidence rate was highest in the winter (358 cases, 31.27%) and lowest in the summer (225 cases, 19.65%). AAD occurred at the highest rate between 19:00-24:00 (321 cases, 28.03%) and the lowest rate between 1:00-6:00 (247 cases, 21.57%). Stanford type A AAD was most prevalent in the winter and the least prevalent in the spring, whereas Stanford type B AAD was most prevalent in the winter and the least prevalent in the summer. The difference between type A and type B in seasonal distribution was significant in spring (χ² = 17.666, P < 0.001) and summer (χ² = 6.228, P = 0.013). Stanford type A cases appeared most during 19:00-24:00 (236 cases, 35.28%) and least during 13:00-18:00 (73 cases, 10.91%), while Stanford type B cases appeared most during 13:00-18:00 (239 cases, 50.21%) and least during 1:00-6:00 (60 cases, 12.61%). The difference between type A and type B in period distribution was significant in all periods of time.

Conclusions: AAD onset followed a chronobiological pattern in patients from northwest China, with winter and 19:00-24:00 being the peak season and time period of AAD occurrence, respectively.