EPID799C section 01: Social justice and inequality – in search of John Cassel’s epidemiology

Main points

Overview

Introductions – Bill Jenkins, Vic Schoenbach, course participants

John Cassel’s epidemiology

Conceptual model of determinants of public health

Organization of the course

The quest for social justice and equality

Phase 1, 1890’s - 1950's:  Working on communities

Phase 2, 1960’s - 1990’s - Working for communities

Phase 3, 2000’s - present’s - Working with communities

 

Contextual factors

Conditions of living are major determinants of health and disease.

These contextual factors include exposure to hazardous (microorganisms, toxic substances, injury, and violence) and protective factors.

Access to resources and power enable people to avoid harmful exposures and to take advantage of protective factors.

As knowledge and capability to prevent or cure diseases become available, then differences in access to that knowledge and capability become primary determinants of health for those diseases.

Dramatically different access to knowledge, resources, and power is the key contextual factor in health inequities in the U.S.

Underlying determinants

Economics

Economic disparities are both the basis of health disparities and in turn are maintained and aggravated by health disparities.

Economic influences are powerful motives for actions that are harmful to other individuals, public health, the environment, and the future.

The economic system has also grown up along with affluence and technological advancement that have transformed human society. Relatively few of us would like to live in the preindustrial era.

Concepts of economics underlie a wide variety of phenomena (investment vs. expenditure, present vs. future, inventory vs. JIT, produce versus trade, etc.)

Evolution

Evolutionary theory – whether one believes in it or not(!) – provides insight into fundamental processes by which life proceeds.

Evolutionary principles apply to plants, animals, people, organizations, societies.

Basic concepts of evolution include: what exists today has, for the most part, survived from the past; over a very long period of time, many things change and unusual events occur; surviving over a very long period of time requires reproduction, diversity, and inheritance.

Cognition

Thinking and behavior greatly influence public health, the environment, and the future.

Thinking may not be what we think it is.

Thinking is influenced by many things that we don’t think about except when we want to influence others.

Short-sightedness, narrow-mindedness, fixations and distractions, failures to see connections and implications, and other shortcomings make our actions less successful than they could be.

In order to improve outcomes, we need to change the way people think.

Neurobiology

The human brain is a community of hundreds of billions of cells and trillions of connections, that forms over an extended period as precursor cells develop into neurons and glial cells, switching some genes on and others off, migrating to appropriate positions, extending axons to make synaptic connections, and undergoing two pruning processes to fine-tune these initial neuronal networks. “Both pruning processes seem to involve competition for limited amounts of specific trophic signals released by the target cells.” Martin Raff, 1996, p1063.

Human thinking and behavior arises from the interactions of this vastly complex world with an environment that includes additional such worlds.

The detailed circuitry of each brain (the “connectome”) is unique, reflecting her blend of genetics, environmental influences, and life experiences.

The developing and adult brain can be influenced by hormonal, nutritional, pharmacologic, microbial, chemical, physical, and social factors.

Early life experiences – or their absence – have lasting impacts on the structure and functioning of the brain, with enduring influence on cognitive and non-cognitive skills, emotions, and resilience.

Consciousness

The quality of functioning of the nervous system determines the quality of our thoughts, actions, and experience of consciousness.

Nervous system functioning and, therefore thinking, behavior, and consciousness, are influenced by genetics,  early life experiences, hormonal milieu, nutrition, sleep, activity, substance use, medications, the physical environment, and the social environment.

Transdisciplinary epidemiologic research could identify and evaluate influences on nervous system functioning, including interventions to improve functioning.

The epidemiology of consciousness could also identify and evaluate influences on breadth of awareness, such as varying tendencies to focus on short term, nearby, highly visible implications of actions to the exclusion of longer term, more distant, and more subtle implications.

Broader awareness could conceivably improve humans’ ability to advance their own wellbeing in the present without sacrificing future wellbeing, the wellbeing of others, and the environment.