The protective effect of beta-carotene and retinol on ventilatory function in an asbestos-exposed cohort.
The association between serum beta-carotene or retinol concentration and level of ventilatory function was investigated in a population of asbestos-exposed men with a high rate of current and former cigarette smoking. The study population consisted of 816 subjects enrolled in the pilot component of the Carotene and Retinol Efficacy Trial (CARET), a placebo-controlled trial of supplemental beta-carotene and retinyl palmitate for the chemoprevention of lung cancer. Data available for analysis included baseline questionnaire, spirometry, chest X-ray, food frequency questionnaire, and serum beta-carotene and retinol concentrations. Serum beta-carotene concentration was associated with FEV1 (p < 0.05) and FVC (p < 0.05), with an approximately 100-ml increase over predicted values associated with raising the serum concentration from the 25th to the 75th percentile of the distribution in the study population (absolute difference = 155 ng/ml), even after adjustment for the confounding effects of asbestos exposure and cigarette smoking. Raising the serum retinol concentration from the 25th to the 75th percentile (absolute difference = 211 ng/ml) was associated with an approximately 70 ml increase in FVC (p < 0.05) over the predicted value. These results provide support for the hypothesis that beta-carotene and retinol have a protective effect on loss of ventilatory function.
Chuwers
P
P
Department of Medicine, University of California, San Francisco 94143-0843, USA.
Barnhart
S
S
Blanc
P
P
Brodkin
C A
CA
Cullen
M
M
Kelly
T
T
Keogh
J
J
Omenn
G
G
Williams
J
J
Balmes
J R
JR
D000368:Aged; D001194:Asbestos; D002986:Clinical Trials as Topic; D003430:Cross-Sectional Studies; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure; D010865:Pilot Projects; D012119:Respiration / Q000502:physiology*; D018570:Risk Assessment; D012907:Smoking / Q000503:physiopathology; D013997:Time Factors; D014797:Vital Capacity; D014801:Vitamin A / Q000097:blood*; D019207:beta Carotene / Q000097:blood*
D019207:beta Carotene; D014801:Vitamin A; D001194:Asbestos