Objectives Numerous studies have shown a positive relationship between temperature variability and mortality, but few studies have investigated the effect of temperature variability on blood pressure (BP). We aimed to estimate the effect of temperature variability on BP in Guangdong Province, southern China. Methods Data on meteorological factors were obtained from the Guangdong Meteorological Center, and BP was collected from a series of cross-sectional surveys conducted in Guangdong Province, China, from 2004 to 2015. There were 38 088 participants aged 18 years and over. A generalized additive model was used to estimate the association between temperature variability and BP after adjusting for confounding variables. Results Our study found a significant positive association between temperature variability and SBP, and this effect increased with the increment of exposure days in total population. The highest estimate was for temperature variability at 7 days lag (TV0–7) with a 0.497 (95% confidence interval, 0.335–0.660) mmHg rise of SBP for each 1°C increase of TV0–7. The effects of TV0–1 and TV0–2 on SBP were higher for hypertensives than that for normotensives, and in warm season higher than that in cold season. However, we did not observe statistical significance between temperature variability and DBP. Conclusions There was a positive association between temperature variability and SBP in Guangdong Province, which should be considered in clinical management and epidemiological survey of hypertension.

Background: Numerous studies have found a positive relationship between temperature variability and mortality, but few studies regarding the effects of temperature variability on blood pressure (BP) are available.Objective: To investigate the effects of temperature variability on BP in Guangdong province, southern China.Methods: Data on Meteorology and BP in Guangdong Province from 2004 to 2015 were collected from Guangdong Provincial Center for Disease Control and Prevention. There were 38088 participants aged 18 years and over. The generalized additive model (GAM) was used to estimate the relationship between temperature variability and BP after adjusting for confounding variables.Result: Our study found that there was a significant positively correlation between temperature variability and systolic blood pressure (SBP), and the estimate increase with the increment of exposure days in total population. The highest estimate was found at 7 days lag with increased 0.497 mmHg of SBP (95%CI: 0.335–0.660) for a 1 °C increase of TV0-7. There was insignificant association between temperature variability and diastolic blood pressure (DBP). The effects of temperature variability on BP among subpopulations with different hypertension statuses were various, and the estimates of Temperature variability with different exposure days on SBP were all higher in known hypertensives than that in normotensives.Conclusion: There was a significant association between temperature variability and SBP in Guangdong province with various effects for different populations. Our findings provide evidence that temperature variability is an independent risk factor for SBP changes, and temperature variability should be considered in hypertension clinic management and epidemiological survey.