Abstract
The objective of this study is to investigate the association between occupational social class and respiratory function, as measured by forced expiratory volume in one-second (FEV1). We examined the cross sectional relationship between lung function and social class in a population study of 21,991 men and women aged 39–79 years living in the general community in Norfolk, United Kingdom, recruited using general practice age–sex registers in 1993–1997. There was a significant socioeconomic gradient in age adjusted lung function with a difference of 0.37 in mean FEV1 in men and 0.20 in women, respectively between social class I and V. The age adjusted OR for having poor lung function was 4.13 (95% CI 2.66–6.42) in men and 2.64 (95% CI 1.74–3.99) in women for social class V compared to I. This difference was substantially attenuated after adjustment for height, weight, smoking status, respiratory illness, educational level, living in a deprived area, physical activity and plasma vitamin C levels. There was a strong socioeconomic gradient in respiratory function. In men the gradient appeared to be largely explained by smoking status and height; in women a large part of the gradient was explained by potentially modifiable factors. This suggests that socioeconomic inequalities in respiratory function may be preventable or modifiable and highlights factors for further exploration.
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Abbreviations
- EPIC-Norfolk:
-
European prospective investigation of cancer and nutrition in Norfolk
- FEV1 :
-
Forced expiratory volume in one-second
- SES:
-
Socioeconomic status
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Acknowledgments
We thank the participants and general practitioners who took part in the study and the staff of EPIC-Norfolk.
Competing interests
The authors declare that they have no competing interests.
Funding
EPIC-Norfolk is supported by research programme grant funding from Cancer Research UK and the Medical Research Council with additional support from the Stroke Association, British Heart Foundation, and Research into Ageing.
Contributors
KTK, SB, and NW are principal investigators in the EPIC-Norfolk population study. SB is responsible for the dietary measurements and analyses. RL is responsible for data management and computing and data linkages for post coding. EM conducted the data analyses and wrote the paper with KTK with contributions from other co-authors.
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McFadden, E., Luben, R., Wareham, N. et al. How far can we explain the social class differential in respiratory function? A cross-sectional population study of 21,991 men and women from EPIC-Norfolk. Eur J Epidemiol 24, 193–201 (2009). https://doi.org/10.1007/s10654-009-9326-y
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DOI: https://doi.org/10.1007/s10654-009-9326-y