Physical activity and bronchial hyperresponsiveness: European Community Respiratory Health Survey II.
BACKGROUND
Identification of the risk factors for bronchial hyperresponsiveness (BHR) would increase the understanding of the causes of asthma. The relationship between physical activity and BHR in men and women aged 28.0-56.5 years randomly selected from 24 centres in 11 countries participating in the European Community Respiratory Health Survey II was investigated.


METHODS
5158 subjects answered questionnaires about physical activity and performed BHR tests. Participants were asked about the frequency and duration of usual weekly exercise resulting in breathlessness or sweating. BHR was defined as a decrease in forced expiratory volume in 1 s of at least 20% of its post-saline value for a maximum methacholine dose of 2 mg.


RESULTS
Both frequency and duration of physical activity were inversely related to BHR. The prevalence of BHR in subjects exercising <or=1, 2-3 and >or=4 times a week was 14.5%, 11.6% and 10.9%, respectively (p<0.001). The corresponding odds ratios were 1.00, 0.78 (95% CI 0.62 to 0.99) and 0.69 (95% CI 0.50 to 0.94) after controlling for potential confounding factors. The frequency of BHR in subjects exercising <1 h, 1-3 h and >or=4 h a week was 15.9%, 10.9% and 10.7%, respectively (p<0.001). The corresponding adjusted odds ratios were 1.00, 0.70 (95% CI 0.57 to 0.87) and 0.67 (95% CI 0.50 to 0.90). Physical activity was associated with BHR in all studied subgroups.


CONCLUSIONS
These results suggest that BHR is strongly and independently associated with decreased physical activity. Further studies are needed to determine the mechanisms underlying this association.
Shaaban
Rafea
R
INSERM U700, Epidémiologie des Maladies Respiratoires, Faculté Xavier Bichat, BP 416, 16 rue Henri Huchard, 75018 Paris, France. shaaban@bichat.inserm.fr
Leynaert
Bénédicte
B
Soussan
David
D
Antó
Josep M
JM
Chinn
Susan
S
de Marco
Roberto
R
Garcia-Aymerich
Judith
J
Heinrich
Joachim
J
Janson
Christer
C
Jarvis
Deborah
D
Sunyer
Jordi
J
Svanes
Cecilie
C
Wjst
Matthias
M
Burney
Peter G
PG
Neukirch
Françoise
F
Zureik
Mahmoud
M
D000328:Adult; D000368:Aged; D001249:Asthma / Q000209:etiology* / Q000503:physiopathology; D015992:Body Mass Index; D016535:Bronchial Hyperreactivity / Q000209:etiology* / Q000503:physiopathology; D001991:Bronchitis; D015444:Exercise / Q000502:physiology*; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D014797:Vital Capacity / Q000502:physiology
D007073:Immunoglobulin E