title: Short-term effects of air temperature on blood pressure and pulse pressure in potentially susceptible individuals.
abstract: BACKGROUND
  Only few epidemiological studies have investigated the association between air temperature and blood pressure (BP) or pulse pressure (PP), with inconsistent findings. We examined whether short-term changes in air temperature were associated with changes in BP or PP in three different populations.
  
  
  METHODS
  Between March 2007 and December 2008, 371 systolic and diastolic BP measurements were collected in 30 individuals with type-2 diabetes mellitus (T2D), 30 persons with impaired glucose tolerance and 42 healthy individuals without a metabolic disorder from Augsburg, Germany. Hourly means of ambient meteorological data were obtained from a fixed measurement station. Personal temperature measurements were conducted using data loggers. Temperature effects were evaluated using additive mixed models adjusting for time trend and relative humidity.
  
  
  RESULTS
  Decreases in air temperature were associated with an increase in systolic BP, diastolic BP and PP in individuals with T2D. For example, a 1°C decrease in ambient temperature was associated with an immediate increase in systolic BP of 1.0 mmHg (95%-confidence interval: [0.5;1.4]mmHg). Effects of personally measured air temperature were similar. Temperature effects were modified by age, body mass index, gender, antihypertensive medication and whereabouts, such as being indoors.
  
  
  CONCLUSIONS
  We observed associations between decreases in air temperature and increases in BP as well as PP in persons with T2D indicating that these people might be potentially more susceptible to changes in air temperature. Our findings may provide a hypothesis for a mechanism between air temperature decreases and short-term increases of cardiovascular events.
authors.affiliation: Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Epidemiology II, 85764 Neuherberg, Germany. Electronic address: stefanie.lanzinger@helmholtz-muenchen.de.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Lanzinger
authors.affiliation: Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Epidemiology II, 85764 Neuherberg, Germany.
authors.forename: Regina
authors.initials: R
authors.lastname: Hampel
authors.affiliation: Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Epidemiology II, 85764 Neuherberg, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Breitner
authors.affiliation: Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Epidemiology II, 85764 Neuherberg, Germany; University of Augsburg, Environmental Science Center, 86159 Augsburg, Germany.
authors.forename: Regina
authors.initials: R
authors.lastname: Rückerl
authors.affiliation: Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Epidemiology II, 85764 Neuherberg, Germany; Ludwig-Maximilians-Universität Munich, Institute for Medical Informatics, Biometrics and Epidemiology, 81377 Munich, Germany.
authors.forename: Ute
authors.initials: U
authors.lastname: Kraus
authors.affiliation: Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Epidemiology II, 85764 Neuherberg, Germany; University of Augsburg, Environmental Science Center, 86159 Augsburg, Germany.
authors.forename: Josef
authors.initials: J
authors.lastname: Cyrys
authors.affiliation: Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Epidemiology II, 85764 Neuherberg, Germany.
authors.forename: Uta
authors.initials: U
authors.lastname: Geruschkat
authors.affiliation: Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Epidemiology II, 85764 Neuherberg, Germany.
authors.forename: Annette
authors.initials: A
authors.lastname: Peters
authors.affiliation: Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Epidemiology II, 85764 Neuherberg, Germany.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Schneider
mesh_terms: D000367:Age Factors; D000368:Aged; D000959:Antihypertensive Agents / Q000627:therapeutic use; D001794:Blood Pressure / Q000502:physiology*; D015992:Body Mass Index; D004781:Environmental Exposure / Q000032:analysis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012737:Sex Factors; D013696:Temperature
chemical_list: D000959:Antihypertensive Agents
keywords: Blood pressure; Epidemiology; Personal measurements; Pulse pressure; Temperature