Acute effects of temperature exposure on blood pressure: An hourly level panel study

Several epidemiological studies have shown that blood pressure changes with temperature based on the daily temperature and linear relationship assumption. However, little is known about the true curve shape of the relationship between temperature and blood pressure.

The objective of this study was to investigate the non-linear relationship between hourly temperature and blood pressure.

This is a prospective panel study comprising 100 participants in Suzhou, China. The blood pressure of each participant was measured >50 times between October 2013 and January 2016. Hourly temperature data were derived from the nearest monitoring station owned by the China Meteorological Administration. A Distributed Lag Nonlinear Model (DLNM) was used to investigate the relationship between hourly temperature and blood pressure.

We found that the relationship between hourly temperature and blood pressure was parabolic. Short-term exposure to hourly temperatures had significant cold and heat effects on systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP), and mean arterial pressure (MAP). The hourly temperature had a significant lag effect on blood pressure, with a lag time of 0-5 h. Alcohol users were more sensitive to the cold effects of hourly temperature, and the diabetic population was more sensitive to the heat effects of hourly temperature on PP.

Temperature imparts short-term effects on blood pressure. Therefore, timely protective measures during cold waves or cold weather are beneficial to maintain stable blood pressure levels to reduce the risk of blood pressure related diseases.