Persistent Chlamydia Pneumoniae serology is related to decline in lung function in women but not in men. Effect of persistent Chlamydia pneumoniae infection on lung function.
BACKGROUND
Chlamydia pneumoniae (C pn) infection causes an acute inflammation in the respiratory system that may become persistent, but little is known about the long-term respiratory effects of C pn infections.


OBJECTIVE
To estimate the long term respiratory effects of C pn with change in forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) as a main outcome variable.


METHODS
The study comprised of 1109 subjects (500 men and 609 women, mean age 28 ± 6 years) that participated in the Reykjavik Heart Study of the Young. Spirometry and blood samples for measurements of IgG antibodies for C pn were done at inclusion and at the end of the follow-up period (mean follow-up time 27 ± 4 years).


RESULTS
Having IgG against C pn at both examinations was significantly associated to a larger decrease in FEV1 (6 mL/year) and FVC (7 mL/year) in women but not in men. In women the association between C pn and larger FEV1 decline was only found in women that smoked at baseline where having C pn IgG was associated with 10 mL/year decline compared to smokers without C pn IgG. These results were still significant after adjustment for age, smoking and change in body weight.


CONCLUSIONS
Our results indicate that persistent C pn serology is related to increased decline in lung function in women but not in men. This effect was, however, primarily found in smoking women. This study is a further indication that the pathophysiological process leading to lung impairment may differ between men and women.
Gislason
Thorarinn
T
University of Iceland, Faculty of Medicine, Reykjavik, Iceland.
Guðdnason
Vilmundur
V
Benediktsdottir
Bryndis
B
Olafsson
Isleifur
I
Aspelund
Thor
T
Thjodleifsson
Bjarni
B
Janson
Christer
C
D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood; D023521:Chlamydophila Infections / Q000382:microbiology* / Q000503:physiopathology*; D016993:Chlamydophila pneumoniae / Q000276:immunology*; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D016014:Linear Models; D008137:Longitudinal Studies; D008168:Lung / Q000503:physiopathology*; D008297:Male; D018410:Pneumonia, Bacterial / Q000382:microbiology* / Q000503:physiopathology*; D012737:Sex Factors; D012907:Smoking / Q000503:physiopathology; D013147:Spirometry; D014797:Vital Capacity; D055815:Young Adult
D000907:Antibodies, Bacterial