People's blood pressure changes 24 hours a day, and it also changes with the seasons. In summer, blood pressure of many patients is easy to control or even low, but it will be significantly increased in winter, and it is still difficult to control even after increasing drugs..

Here are the reason. First, the cold weather in winter encourages blood vessels to constrict. Second, people get less exercise and reduce their sodium output.

Excessive elevation of blood pressure will significant increase the incidence of myocardial infarction, heart failure, cerebral thrombosis and cerebral hemorrhage,which are associated with increased mortality and disability.