Environmental Science and Pollution Research

, Volume 22, Issue 11, pp 8756–8762 | Cite as

Weather as physiologically equivalent was not associated with ischemic stroke onsets in Vienna, 2004–2010

  • Julia Ferrari
  • Ivy Shiue
  • Leonhard Seyfang
  • Andreas Matzarakis
  • Wilfried Lang
  • for the Austrian Stroke Registry Collaborators
Short Research and Discussion Article


Stroke rates were found to have seasonal variations. However, previous studies using air temperature, humidity, or air pressure separately were not adequate, and the study catchment was not clearly drawn. Therefore, here we proposed to use a thermal index called physiologically equivalent temperature (PET) that incorporates air temperature, humidity, wind speed, cloud cover, air pressure and radiation flux from a biometeorological approach to estimate the effect of weather as physiologically equivalent on ischemic stroke onsets in an Austrian population. Eight thousand four hundred eleven stroke events in Vienna registered within the Austrian Stroke Unit Register from January 1, 2004 to December 31, 2010 were included and were correlated with the weather data, obtained from the Central Institute for Meteorology and Geodynamics in the same area and study time period and calculated as PET (°C). Statistical analysis involved Poisson regression modeling. The median age was 74 years, and men made up 49 % of the entire population. Eighty percent had hypertension while 25.4 % were current smokers. Of note, 26.5 % had diabetes mellitus, 28.9 % had pre-stroke, and 11.5 % had pre-myocardial infarction. We have observed that onsets were higher on the weekdays than on the weekend. However, we did not find any significant association between PETs and ischemic stroke onsets by subtypes in Vienna. We did not observe any significant associations between PETs and ischemic stroke onsets by subtypes in Vienna. Hospital admission peaks on the weekdays might be due to hospital administration reasons.


Stroke Risk factor Weather Biometeorology Hospital admissions 



IS was supported by University of Exeter Outward Mobility Fellowship when initiating the international research collaboration and is now supported by the Global Platform for Research Leaders scheme.

Conflict of interest



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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Julia Ferrari
    • 1
  • Ivy Shiue
    • 2
  • Leonhard Seyfang
    • 3
  • Andreas Matzarakis
    • 4
  • Wilfried Lang
    • 1
  • for the Austrian Stroke Registry Collaborators
  1. 1.Department of NeurologySt. John of God HospitalViennaAustria
  2. 2.School of Energy, Geoscience, Infrustructure & SocietyHeriot-Watt UniversityEdinburghUK
  3. 3.Department of Clinical Medicine and Preventive MedicineDanube University KremsKrems an der DonauAustria
  4. 4.Meteorological InstituteAlberts-Ludwigs-University FreiburgFreiburg im BreisgauGermany

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