title: Effects of Meteorological Conditions on the Risk of Ischemic Stroke Events in Patients Treated with Alteplase--HEWS-tPA.
abstract: BACKGROUND
  Predicting a day that presents a high risk for the occurrence of ischemic stroke events may enable health professionals to prepare for emergency stroke therapy more properly. We evaluated the association between meteorological conditions and the frequency of ischemic stroke events in Japanese patients.
  
  
  METHODS
  Ischemic stroke patients (n = 299) who were treated with alteplase at 9 stroke hospitals in 3 restricted areas were examined. The daily rates of ischemic stroke events were compared with the daily mean thermo-hydrological index (THI), the atmospheric pressure, and the daily changes of these variables for the 6 days preceding an ischemic stroke event using Poisson regression analysis.
  
  
  RESULTS
  We trisected onset days based on the THI (low-temperature, intermediate-temperature, and high-temperature), atmospheric pressure (low-pressure, intermediate-pressure, and high-pressure), changes in THI for preceding 6 days from the previous day (cooler, unchanged-temperature, and warmer), and changes in atmospheric pressure (decreased-pressure, unchanged-pressure, and increased-pressure). The frequency of ischemic stroke was significantly higher on low-temperature or high-pressure days (risk ratio, 1.398, P = .022; risk ratio, 1.374, P = .039), on warmer-temperature days, and when atmospheric pressure varied from the day before (P < .05). There were significantly lower risks for ischemic stroke events on cooler-temperature days, and higher risks were associated with a variation in atmospheric pressure 3 days before the onset from 4 days before (P < .05).
  
  
  CONCLUSIONS
  There were higher risks for ischemic stroke events associated with low ambient temperature, high atmospheric pressure, increased temperature, and varied atmospheric pressure. Also, atmospheric pressure variation 3 days before may be associated.
authors.affiliation: Department of Neurology, National Hospital Organization Kure Medical Center, Kure, Japan.
authors.forename: Yoshimasa
authors.initials: Y
authors.lastname: Sueda
authors.affiliation: Department of Clinical Neuroscience and Therapeutics, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan. Electronic address: nhosomi@hiroshima-u.ac.jp.
authors.forename: Naohisa
authors.initials: N
authors.lastname: Hosomi
authors.affiliation: Department of Health Informatics, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Miwako
authors.initials: M
authors.lastname: Tsunematsu
authors.affiliation: Department of Neurology, Brain Attack Center Ota Memorial Hospital, Fukuyama, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Takamatsu
authors.affiliation: Department of Neurology, Suiseikai Kajikawa Hospital, Hiroshima, Japan.
authors.forename: Eiichi
authors.initials: E
authors.lastname: Nomura
authors.affiliation: Department of Neurology, National Hospital Organization Kure Medical Center, Kure, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Torii
authors.affiliation: Department of Clinical Neuroscience and Therapeutics, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Toshiho
authors.initials: T
authors.lastname: Ohtsuki
authors.affiliation: Department of Clinical Neuroscience and Therapeutics, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Shiro
authors.initials: S
authors.lastname: Aoki
authors.affiliation: Department of Clinical Neuroscience and Therapeutics, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Mukai
authors.affiliation: Department of Clinical Neuroscience and Therapeutics, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Nezu
authors.affiliation: Department of Health Informatics, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Kakehashi
authors.affiliation: Department of Clinical Neuroscience and Therapeutics, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Masayasu
authors.initials: M
authors.lastname: Matsumoto
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001274:Atmospheric Pressure; D002545:Brain Ischemia / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology; D005260:Female; D005343:Fibrinolytic Agents / Q000008:administration & dosage / Q000009:adverse effects*; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D018570:Risk Assessment; D012307:Risk Factors; D020521:Stroke / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology; D013696:Temperature; D015912:Thrombolytic Therapy / Q000009:adverse effects*; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000008:administration & dosage / Q000009:adverse effects*; D016896:Treatment Outcome; D014887:Weather
chemical_list: D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator
keywords: Meteorological conditions; ischemic stroke; prediction; stroke