Whitehall Study

The original Whitehall Study investigated social determinants of health, specifically the cardiorespiratory disease prevalence and mortality rates among British male civil servants between the ages of 20 and 64. The initial study, the Whitehall I Study, was conducted over a period of ten years, beginning in 1967. A second phase, the Whitehall II Study, examined the health of 10,308 civil servants aged 35 to 55, of whom two thirds were men and one third women. A long-term follow-up of study subjects from the first two phases is ongoing. The Whitehall studies found a strong association between grade levels of civil servant employment and mortality rates from a range of causes. Men in the lowest grade (messengers, doorkeepers, etc.) had a mortality rate three times higher than that of men in the highest grade (administrators).

Whitehall I

The first phase of the Whitehall studies, or Whitehall I, found there were higher mortality rates in men of lower employment grade specifically due to coronary heart disease, as well as increased mortality rates due to all causes for lower status men.

The initial Whitehall study found lower grades, and thus status, were clearly associated with greater propensities for significant risk factors, including obesity, smoking, reduced leisure time and physical activity, more baseline illness, higher blood pressure, and shorter height. Controlling for these risk factors accounted for no more than 40% of grade differences in cardiovascular disease mortality. Even after these standard risk factors were controlled for, the lowest grade still had a relative risk of 2.1 for cardiovascular disease mortality compared to the highest grade.

Whitehall II

Whitehall II is a longitudinal, prospective cohort study of 10,308 women and men all of whom were employed in the London offices of the British Civil Service on recruitment to the study in 1985. The baseline data collection included a clinical examination and self-report questionnaire. Since baseline, eight waves of data collection have been completed and the ninth wave began in October 2007. The name Whitehall II is derived from a previous study of over 18,000 civil servants (the first Whitehall study) all men. Further information is available from http://www.ucl.ac.uk/whitehallII/

The Whitehall studies have dispelled two myths. The first is that people in high status jobs have higher risks of heart disease. The second is that the gradient of health in industrialised societies is simply a matter of poor health for the disadvantaged and good health for everyone else.

How did the Whitehall studies dispel these misconceptions? The first Whitehall Study compared mortality of people in the highly stratified environment of the British Civil Service. It showed that among British civil servants, none of whom was poor in the absolute sense, there was a social gradient in mortality that ran from the bottom to the top of society. The more senior one was in the employment hierarchy, the longer one might expect to live compared to people in lower employment grades. Twenty years later, the Whitehall II study documented a similar gradient in morbidity in women as well as men. A striking finding from the Whitehall Studies was that the social gradient was observed for a range of different diseases: heart disease, some cancers, chronic lung disease, gastrointestinal disease, depression, suicide, sickness absence, back pain and general feelings of ill-health. A major challenge, and a reason for the importance of these studies, was to understand the causes of this social distribution of so many disorders.

The Whitehall studies have gone some way toward unravelling the mystery of why someone in the middle of the social hierarchy should have worse health than those above them and better health than those below them. Research continues to explore the pathways and mechanisms through which social position influences health. The research group aims to build a causal model leading from social position through psychosocial and behavioural pathways to pathophysiological changes, sub-clinical markers of disease, functional change, and clinical disease.

The Whitehall II study began as a study of working age people and investigated the relationships between work, stress, and health. Whitehall II found that the way work is organised, the work climate, social influences outside work, influences from early life, in addition to health behaviours all contribute to the social gradient in health. As participants in this study continue through adult life, the research is focusing on inequalities in health and functioning in an aging population. With an increasingly large population of older citizens in the UK, there is an urgent need to identify the causes of social inequalities and to study the long term effects of previous circumstances on people’s ability to function and stay healthy during retirement. Further information regarding findings from the Whitehall II study is available from http://www.ucl.ac.uk/whitehallII/findings/Whitehallbooklet.pdf.

The social gradient in health is not a phenomenon confined to the British Civil Service. Throughout the developed world, wherever researchers have had data to investigate, they have observed the social gradient in health. Health inequalities are a global issue affecting people across the social gradient in rich, middle income, and poor countries. In order to address inequalities in health it is necessary both to understand how social organisation affects health and to find ways to improve the conditions in which people work and live. Professor Sir Michael Marmot chairs the Commission on Social Determinants of Health (CSDH; 2005-2008) set up by the World Health Organisation (see http://www.who.int/social_determinants/advocacy/interview_marmot/en/). The Commission on Social Determinants of Health was set up in 2005. During the past couple of years, it has sought to engage with policy makers, global institutions and civil society on the issues around health inequalities within and between countries, the social determinants of health and action to address these issues. The CSDH is acting as a catalyst for change, working with countries, academics and civil society to bring health inequalities to the fore in the national policy dialogue. The overarching goals of the CSDH are to improve population health, to reduce health inequities, and to reduce disadvantages due to ill health.

Health risks associated with disparities of wealth and power

By design, the Whitehall studies have been focused upon a single swath of related occupations, wherein relatively little heterogeneity exists within occupational grades, yet clear social distinctions between grades are inherent. The studies were designed in this manner as an attempt to avoid certain research drawbacks associated with generalized social class groupings, drawbacks that otherwise would result from the diversity of occupations within social classes, which in turn would tend to reduce the potential objectivity of analyses.

The primary health risks under investigation in the Whitehall studies include cardiovascular function, smoking, car ownership, angina, leisure/hobbies, ECG measurements, and diabetes.

High blood pressure at work was associated with greater 'job stress', including 'lack of skill utilization', 'tension', and 'lack of clarity' in tasks assigned. The higher blood pressure among the lowest grade servants was found to be related to the highest job stress score, whereas blood pressure at home was not related to job stress level.

According to Whitehall study researchers, "a steep inverse association between social class, as assessed by grade of employment, and mortality from a wide range of diseases" has been demonstrated. Summing up the moral of the Whitehall studies, the researchers concluded that "more attention should be paid to the social environments, job design, and the consequences of income inequality."

Direction

The study is directed by Professor Michael Marmot of the Department of Epidemiology and Public Health at University College London. Marmot is currentlywhen the commissioner of the World Health Organization's Commission on Social Determinants of Health. [http://www.who.int/social_determinants/en/]

External links

* [http://www.statistics.gov.uk/STATBASE/Source.asp?vlnk=1326&More=Y Statistics.gov.uk] - 'Whitehall Study' (statistical database)
* [http://www.ucl.ac.uk/whitehallII/research/Cohortprofile.pdf UCL.ac.uk (pdf)] - 'Cohort Profile: The Whitehall II Study'
* [http://www.workhealth.org/projects/pwhitew.html WorkHealth.org] - 'The Whitehall Study' (summary), Michael Marmot
* [http://www.workhealth.org/projects/pwhiteabs.html WorkHealth.org] - 'Selected Abstracts from the Whitehall II Study', Marmot, "et al."