The association between wind-related variables and stroke symptom onset: A case-crossover study on Jeju Island.
Although several studies have investigated the effects of ambient temperature on the risk of stroke, few studies have examined the relationship between other meteorological conditions and stroke. Therefore, the aim of this study was to analyze the association between wind-related variables and stroke symptoms onset.



Data regarding the onset of stroke symptoms occurring between January 1, 2006, and December 31, 2007 on Jeju Island were collected from the Jeju National University Hospital stroke registry. A fixed-strata case-crossover analysis based on time of onset and adjusted for ambient temperature, relative humidity, air pressure, and pollutants was used to analyze the effects of wind speed, the daily wind speed range (DWR), and the wind chill index on stroke symptom onset using varied lag terms. Models examining the modification effects by age, sex, smoking status, season, and type of stroke were also analyzed.



A total of 409 stroke events (381 ischemic and 28 hemorrhagic) were registered between 2006 and 2007. The odds ratios (ORs) for wind speed, DWR, and wind chill among the total sample at lag 0-8 were 1.18 (95% confidence interval (CI): 1.06-1.31), 1.08 (95% CI: 1.02-1.14), and 1.22 (95% CI: 1.07-1.39) respectively. The ORs for wind speed, DWR, and wind chill for ischemic stroke patients were slightly greater than for patients in the total sample (OR=1.20, 95% CI: 1.08-1.34; OR=1.09, 95% CI: 1.03-1.15; and OR=1.22, 95% CI: 1.07-1.39, respectively). Statistically significant season-specific effects were found for spring and winter, and various delayed effects were observed. In addition, age, sex, and smoking status modified the effect size of wind speed, DWR, and wind chill.



Our analyses showed that the risk of stroke symptoms onset was associated with wind speed, DWR, and wind chill on Jeju Island.
Institute of Health and Environment, Seoul National University, Seoul, Republic of Korea.
Jayeun
J
Kim
Nursing Science Research Institute, Chung-Ang University, Seoul, Republic of Korea.
Kyuhyun
K
Yoon
Department of Neurology, School of Medicine, Jeju National University, Jeju, Republic of Korea.
Jay Chol
JC
Choi
Institute of Health and Environment, Seoul National University, Seoul, Republic of Korea; Department of Biostatistics and Epidemiology, Graduate School of Public Health, Seoul National University, Seoul, Republic of Korea.
Ho
H
Kim
Department of Preventive Medicine, School of Medicine, Jeju National University, 1-Ara-1-dong, Jeju-si, Jeju, Republic of Korea. Electronic address: salbab@hotmail.com.
Jung-Kook
JK
Song
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000393:Air Pollutants / Q000633:toxicity; D016022:Case-Control Studies; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D056910:Republic of Korea / Q000453:epidemiology; D012307:Risk Factors; D020521:Stroke / Q000139:chemically induced / Q000145:classification / Q000453:epidemiology* / Q000209:etiology; D014919:Wind; D055815:Young Adult
D000393:Air Pollutants
Case-crossover; Stroke; Temperature; Wind chill index; Wind speed