Background: Urban populations worldwide are of increasingly diverse ethnicity. International recommendations suggest that ethnically specific norms should be applied when assessing spirometry, although the lower forced vital capacity (FVC) in African Americans is associated with lower survival.
Objective: To assess differences in ventilatory function in a current, ethnically diverse British population.
Methods: In a cross-sectional survey of three primary care practices in West London, 677 participants aged ≥40 years provided acceptable post-bronchodilator spirometric data. Ethnicity was self-defined using the British Census questions and grouped as 'White', 'African-Caribbean' and 'Other'.
Results: After adjustment, the ratio of 1-second forced expiratory volume (FEV(1)) to FVC was 1.0% (95%CI -2.5 to 4.5) higher in Black men and 1.8% (-0.8 to 4.4) higher in Black women compared with the White population. In contrast, FVC was 870 ml (-1140 to -600) lower in Black men and 590 ml (-760 to -420) lower in Black women. Participants from 'Other' ethnic groups had results similar to those of Black participants.
Conclusions: The FEV(1)/FVC ratio can be used without regard to ethnic background to assess obstruction. However, FVC is systematically lower in all minority ethnic groups.