Background Acute aortic dissection（AAD） is characterized by acute onset and rapid progress.Some patients die before reaching hospital.But available studies concerning time interval from onset of AAD to hospital admission are rare.Objective This study aimed to explore the time interval from onset of AAD to first hospital admission and associated factors in AAD patients，providing theoretical support for shortening prehospital time to timely obtain hospital care in such patients.Methods A total of 173 patients with AAD from department of cardiac macrovascular surgery of a grade A tertiary hospital，Wuhan were enrolled during March to November，2018.A self-developed questionnaire named Prehospital Time in Acute Aortic Dissection Patients was used to survey the patients to collect demographics，AAD-related factors and factors possibly associated with prehospital time.Multiple linear regression analysis was used to determine the factors associated with prehospital time.Results The survey obtained a response rate of 86.50%（173/200）.The prehospital time in the 173 respondents was 12-20 350 minutes〔averaged 70.0（36.5，150.0）〕 minutes.The prehospital time varied significantly according to education level，monthly income，prevalence of independent living，time required to access to the nearest medical institution from home，history of past illness（i.e.gastric disease），smoking and drinking prevalence，onset symptoms （chest or back pain，profuse sweating，dyspnea），level of pain at onset，prevalence of persistent pain at onset，history of symptoms similar to onset symptoms，perceptions of AAD，onset time，what is being done at the onset time，bystander response，self-perceived severity of disease，means of admission（by dialing 120 to call an ambulance，going to the hospital by oneself or under the help of others，by calling for help，seeking hospital care due to other diseases），and prehospital interventions（try to rest or relax，bearing the suffering till symptom relief，medication） （P<0.05）.Multiple linear regression analysis showed that education level，time required to access to the nearest medical institution from home，prevalence of persistent pain at onset，bystander response，self-perceived severity of disease，going to the hospital by taxi，and seeking hospital care due to other diseases were associated with the prehospital time（P<0.05）.Conclusion Higher education level was associated with shorter time used to access to the nearest medical institution from home.Higher self-perceived severity of disease was associated with shorter prehospital time.Moreover，having persistent pain at the onset，positive response of the bystanders，and dialing 120 to call an ambulance were associated with shorter prehospital time.However，seeking hospital care due to other diseases was associated with longer prehospital time.In view of this，to shorten the prehospital time to timely obtain hospital care，public perceptions and vigilance consciousness of AAD need to be improved，active interventions should be taken after the onset，and dialing 120 to call an ambulance is recommended.
