Only a few studies have attempted to
quantify the effect of socioeconomic status on
indices of lung function. In a study comparing
mortality in manual and non-manual workers
in two British towns, respiratory symptoms and
impairment of lung function was found to differ
across social class. The difference in
forced expiratory volume in one second (FEV1)
was 7–15% of FEV1% predicted and was not
affected by stratification by smoking history. In
a study of 410 male non-smokers, Stebbings et
al14 found that the difference in FEV1 between
the highest and lowest social class was 400 ml.14 A similar result was found in the
Copenhagen City Heart Study in which the
difference between the highest and lowest
socioeconomic group was 400 ml for men and
259 ml for women after adjustment for
smoking.25 This difference was reflected in a
threefold higher risk of admission to hospital
for chronic obstructive pulmonary disease
(COPD) in subjects of the lowest compared
with the highest socioeconomic group, and was
not affected by adjustment for smoking. Interestingly,
similar risk ratios for death from respiratory
disease were seen in the Whitehall
study.