title: Season and outdoor temperature in relation to detection and control of hypertension in a large rural Chinese population.
abstract: BACKGROUND
  In many Western populations, blood pressure varies moderately with season and outdoor temperature. Relatively little is known about effects of seasonal changes in blood pressure on the detection and control of hypertension in general populations, especially in low- and middle-income countries.
  
  
  METHODS
  We analysed cross-sectional data of 57 375 (42% men) participants aged 30-79 (mean 52.3) years who were enrolled during 2004-08, as part of the China Kadoorie Biobank, from a rural county in the south-east costal Zhejiang Province. Analyses related daily mean outdoor temperature, obtained from local Meteorological Bureau, to mean systolic (SBP) and diastolic blood pressure (DBP), rate of newly detected hypertension and, among those with self-reported physician-diagnosed hypertension, rate of adequate blood pressure control, using multiple linear and logistic regression models.
  
  
  RESULTS
  The overall mean blood pressure was 135.9 mmHg for SBP and 80.5 mmHg for DBP. Daily outdoor temperature ranged between -2.9 and 33.7°C, with July being the hottest month (mean 29.4°C) and January the coldest (mean 4.0°C). Comparing January (the coldest month) with July (the warmest), the differences in the adjusted SBP/DBP were 19.2/7.7 mmHg. Each 10°C lower ambient temperature was associated with 6.9/2.9 mmHg higher SBP/DBP,14.1% higher prevalence of newly detected hypertension and, among those with pre-diagnosed hypertension, 13.0% lower hypertension control rate.
  
  
  CONCLUSIONS
  In rural China, lower outdoor temperature is strongly associated with higher mean blood pressure and hypertension prevalence as well as poorer hypertension control, and should be considered when conducting population-based hypertension surveys and providing treatment for hypertensive patients.
authors.affiliation: Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang, China, Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, Oxford, UK, Tongxiang Centre for Disease Control and Prevention, Zhejiang Province, China, Chinese Academy of Medical Sciences, Beijing, China and School of Public Health, Peking University Health Sciences Center, Beijing, China.
authors.forename: Danting
authors.initials: D
authors.lastname: Su
authors.affiliation: Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang, China, Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, Oxford, UK, Tongxiang Centre for Disease Control and Prevention, Zhejiang Province, China, Chinese Academy of Medical Sciences, Beijing, China and School of Public Health, Peking University Health Sciences Center, Beijing, China.
authors.forename: Huaidong
authors.initials: H
authors.lastname: Du
authors.affiliation: Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang, China, Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, Oxford, UK, Tongxiang Centre for Disease Control and Prevention, Zhejiang Province, China, Chinese Academy of Medical Sciences, Beijing, China and School of Public Health, Peking University Health Sciences Center, Beijing, China.
authors.forename: Xinwei
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang, China, Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, Oxford, UK, Tongxiang Centre for Disease Control and Prevention, Zhejiang Province, China, Chinese Academy of Medical Sciences, Beijing, China and School of Public Health, Peking University Health Sciences Center, Beijing, China.
authors.forename: Yijian
authors.initials: Y
authors.lastname: Qian
authors.affiliation: Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang, China, Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, Oxford, UK, Tongxiang Centre for Disease Control and Prevention, Zhejiang Province, China, Chinese Academy of Medical Sciences, Beijing, China and School of Public Health, Peking University Health Sciences Center, Beijing, China myu@cdc.zj.cn lmlee@vip.163.com zhengming.chen@ctsu.ox.ac.uk.
authors.forename: Lingli
authors.initials: L
authors.lastname: Chen
authors.affiliation: Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang, China, Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, Oxford, UK, Tongxiang Centre for Disease Control and Prevention, Zhejiang Province, China, Chinese Academy of Medical Sciences, Beijing, China and School of Public Health, Peking University Health Sciences Center, Beijing, China.
authors.forename: Yaping
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang, China, Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, Oxford, UK, Tongxiang Centre for Disease Control and Prevention, Zhejiang Province, China, Chinese Academy of Medical Sciences, Beijing, China and School of Public Health, Peking University Health Sciences Center, Beijing, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Guo
authors.affiliation: Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang, China, Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, Oxford, UK, Tongxiang Centre for Disease Control and Prevention, Zhejiang Province, China, Chinese Academy of Medical Sciences, Beijing, China and School of Public Health, Peking University Health Sciences Center, Beijing, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Bian
authors.affiliation: Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang, China, Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, Oxford, UK, Tongxiang Centre for Disease Control and Prevention, Zhejiang Province, China, Chinese Academy of Medical Sciences, Beijing, China and School of Public Health, Peking University Health Sciences Center, Beijing, China myu@cdc.zj.cn lmlee@vip.163.com zhengming.chen@ctsu.ox.ac.uk.
authors.forename: Zhengming
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang, China, Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, Oxford, UK, Tongxiang Centre for Disease Control and Prevention, Zhejiang Province, China, Chinese Academy of Medical Sciences, Beijing, China and School of Public Health, Peking University Health Sciences Center, Beijing, China Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang, China, Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, Oxford, UK, Tongxiang Centre for Disease Control and Prevention, Zhejiang Province, China, Chinese Academy of Medical Sciences, Beijing, China and School of Public Health, Peking University Health Sciences Center, Beijing, China myu@cdc.zj.cn lmlee@vip.163.com zhengming.chen@ctsu.ox.ac.uk.
authors.forename: Liming
authors.initials: L
authors.lastname: Li
authors.affiliation: Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang, China, Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, Oxford, UK, Tongxiang Centre for Disease Control and Prevention, Zhejiang Province, China, Chinese Academy of Medical Sciences, Beijing, China and School of Public Health, Peking University Health Sciences Center, Beijing, China myu@cdc.zj.cn lmlee@vip.163.com zhengming.chen@ctsu.ox.ac.uk.
authors.forename: Min
authors.initials: M
authors.lastname: Yu
mesh_terms: D000328:Adult; D000368:Aged; D000959:Antihypertensive Agents / Q000627:therapeutic use; D001794:Blood Pressure / Q000502:physiology; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D006973:Hypertension / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012424:Rural Population / Q000706:statistics & numerical data*; D012621:Seasons; D013696:Temperature; D016896:Treatment Outcome
chemical_list: D000959:Antihypertensive Agents
keywords: Blood pressure; China; hypertension control; hypertension detection; outdoor temperature; season