Serum carotenoids, vitamins A and E, and 8 year lung function decline in a general population.
BACKGROUND
Oxidative stress is thought to have a major role in the pathogenesis of airway obstruction. A study was undertaken to determine whether subjects with low levels of antioxidants (serum beta-carotene, alpha-carotene, vitamins A and E) would be at a higher risk of accelerated decline in forced expiratory volume in 1 second (FEV1) as their lungs would be less protected against oxidative stress.


METHODS
1194 French subjects aged 20-44 years were examined in 1992 as part of the European Community Respiratory Health Survey (ECRHS); 864 were followed up in 2000 and 535 (50% men, 40% lifelong non-smokers) had complete data for analysis.


RESULTS
During the 8 year study period the mean annual decrease in FEV1 (adjusted for sex, centre, baseline FEV1, age, smoking, body mass index and low density lipoprotein cholesterol) was 29.8 ml/year. The rate of decrease was lower for the subjects in tertile I of beta-carotene at baseline than for those in the two other tertiles (-36.5 v -27.6 ml/year; p = 0.004). An increase in beta-carotene between the two surveys was associated with a slower decline in FEV1. No association was observed between alpha-carotene, vitamin A, or vitamin E and FEV(1) decline. However, being a heavy smoker (> or =20 cigarettes/day) in combination with a low level of beta-carotene or vitamin E was associated with the steepest decline in FEV1 (-52.5 ml/year, p = 0.0002 and -50.1 ml/year, p = 0.010, respectively).


CONCLUSIONS
These results strongly suggest that beta-carotene protects against the decline in FEV1 over an 8 year period in the general population, and that beta-carotene and vitamin E are protective in heavy smokers.
Guénégou
A
A
Department of Epidemiology INSERM Unit 700, University of Medicine Bichat, 16 rue Henry Huchard, 75018 Paris, France. guenegou@bichat.inserm.fr
Leynaert
B
B
Pin
I
I
Le Moël
G
G
Zureik
M
M
Neukirch
F
F
D000328:Adult; D000402:Airway Obstruction / Q000097:blood / Q000503:physiopathology*; D000975:Antioxidants / Q000378:metabolism*; D015992:Body Mass Index; D002338:Carotenoids / Q000097:blood*; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012907:Smoking / Q000097:blood / Q000503:physiopathology; D014801:Vitamin A / Q000097:blood*; D014810:Vitamin E / Q000097:blood*; D019207:beta Carotene / Q000097:blood*
D000975:Antioxidants; D019207:beta Carotene; D014801:Vitamin A; D014810:Vitamin E; D002338:Carotenoids; C041635:alpha-carotene