Reference No.: 58
Title: Employment grade and coronary heart disease in British civil servants (a.k.a The Whitehall study)
Author: M G Marmot, G Rose, M Shipley, P J Hamilton
Primary Topic: Health
Year: 1978
URL: https://doi.org/10.1136/jech.32.4.244
My notes on this reference #
Background
- The study investigated the relationship between employment grade, coronary risk factors, and coronary heart disease (CHD) mortality in British civil servants.
- A total of 17,530 men in London were followed over 7.5 years.
Findings on Employment Grade and CHD
- CHD mortality was inversely related to employment grade.
- Men in the lowest grade (“other”) had 3.6 times the CHD mortality rate of those in the highest grade (administrators).
- This gradient persisted even after adjusting for risk factors like smoking, blood pressure, and physical activity.
Coronary Risk Factors
- Lower-grade men exhibited:
- Higher rates of smoking (60.9% in “other” grade vs. 28.8% in administrators).
- Increased inactivity during leisure time (56% in “other” grade vs. 26.3% in administrators).
- Higher blood pressure, plasma glucose, and body mass index.
- Higher-grade men had higher plasma cholesterol levels.
Residual Risk Factors
- Approximately 60% of the grade differences in CHD mortality could not be explained by traditional risk factors.
- Other factors, such as psychosocial stress and unmeasured environmental or lifestyle variables, were suggested as potential contributors.
Height and CHD
- Men in lower grades were shorter on average.
- Height was independently associated with CHD risk, possibly reflecting genetic or early-life nutritional factors.
Selection and Bias Considerations
- Selection into lower-grade jobs due to pre-existing health issues was evaluated.
- The mortality gradient persisted even among healthy men at baseline, indicating minimal impact from selection bias.
Implications
- Employment grade is a strong predictor of CHD mortality, stronger than many established risk factors.
- Further research was suggested into psychosocial stress, diet, and other unmeasured contributors to the social gradient in CHD.