Aromatic amine exposure and oesophageal cancer.

Sir—We appreciate Dr Liu's suggestions regarding a number of factors that may account for the relationships we reported between pattern of alcohol intake and body mass index in the Lung Health Study. Some of these hypotheses can be addressed by supplementary analyses and others are beyond the scope of data obtained in the Lung Health Study. First, control for the degree of lung impairment— expressed as either the forced expiratory volume in one second (FEV1) or the ratio of this measure to the forced vital capacity (FEV1/FVC)—had no effect on the strength of the relationships we reported, although as would be expected, both lung function parameters had a significant independent relationship with body mass index. Second, collinearity between total weekly alcohol intake and drinks per drinking day is not a likely explanation for these findings. As noted in the original paper, the Lung Health Study specifically excluded