Causes and „causes of the causes‟ of chronic conditions Professor Brian Oldenburg

Learning objectives 1. To identify causes and „causes of causes‟ for common chronic NCDs. 2. To understand the interrelationships and „web of causation‟ among these causes and influences 3. To understand the important role of neighbourhood or environmental level factors.

Health 

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“Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity” Health Promotion Glossary…. http://www.who.int/hpr/NPH/docs/hp_glossary_ en.pdf

A framework for understanding the ‘causes of the causes’ of health and ill health Broad features of society

Socioeconomic influences

Culture Resources Systems Policies Affluence Social cohesion Media

Education Employment Income and wealth Family, neighbourhood Access to services Housing

Environmental factors

Knowledge, attitudes and beliefs

Health behaviours Tobacco use Physical activity Alcohol consumption Use of illicit drugs Dietary behaviour Sexual behaviours Vaccination status Psychological factors Safety factors

Natural environment Built environment

Individual physical and psychological makeup (genetics; ageing; life course and intergenerational influences)

Source: Australian Institute of Health and Welfare (AIHW) 2008. Fig 4.1

Biomedical risk factors Blood pressure Blood cholesterol Body weight Impaired glucose regulation Immune status ETC

Individual and population health and functioning

Proven Risk Factors for Cardiovascular Diseases Risk factors that are causally linked: Tobacco consumption Elevated LDL Low HDL High blood pressure Elevated glucose Physical inactivity* Obesity* Diet* * Predisposing risk factors

Yusuf et al Global Burden of Cardiovascular Diseases: Part I: General Considerations, the Epidemiologic Transition, Risk Factors, and Impact of Urbanization Circulation 2001; 104;2746-2753

www.monash.edu.au 6

Other (‘non-traditional’) Risk Factors for Cardiovascular Diseases Risk markers that show associations: 1. Low socioeconomic status* 2. Elevated prothrombotic factors: fibrinogen, plasminogen activator inhibitor 3. Markers of infection or inflammation 4. Elevated homocysteine 5. Elevated lipoprotein(a) 6. Psychosocial risk factors (partic. depression) and lack/loss of social support * Predisposing risk factors

www.monash.edu.au 7

Tobacco Tobacco use is a risk factor for six of the eight leading causes of death in the world

(WHO, 2008)

Noncommunicable diseases >

Top seven selected risk factors and the burden of disease

Source: Australian Institute of Health and Welfare (AIHW) 2008. Table 4.1

DRIVERS OF THE CVD EPIDEMIC

• Urbanisation • Global trade and marketing developments • Tobacco industry

• Physical inactivity Tobacco use, inappropriate diet and physical inactivity (expressed through unfavourable lipid profiles, overweight and raised BP) explain at least 75% of new CHD cases Global CVD

Links between social structure, health & disease Social structure

Material factors

Work

Social environment

Psychological Brain

Health behaviours

Neuroendocrine and immune response

Pathophysiological changes Organ impairment

Early life Genes Culture

Well-being Morbidity Mortality

Source: WHO Commission on Social Determinants of Health 2005

Social determinants of health

Causal pathways 

Necessary causes

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Sufficient causes

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Statisical argument

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Contested

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Not well understood

Health inequalities 

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Due to many factors 

Age

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Socioeconomic status

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Aboriginal origin

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Rural residence

Views of these vary

Health promotion and public health responses to these also vary

Health and GDP

Health system and health

When was this written? 

“Medicine has imperceptibly led us into the social field and placed us in a position of confronting directly the great problems of our time...we must begin to promote the advancement of the entire population...”

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Education

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Employment

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Social participation

The web of causation………

UPSTREAM (MACRO) FACTORS

MIDSTREAM (INTERMEDIATE) FACTORS Health Care System

Government Policies Global Forces

Determinants of Health

Physiological Systems

Psychosocial Factors

(social, physical, economic, environmental)

Culture

DOWNSTREAM (MICRO) FACTORS

Health

Health Behaviours

Biological Reactions

Culture Priority Groups

Life Stages

Settings & Contexts

©Queensland University of Technology, School of Public Health , Centre for Public Health Research (Turrell et al, )

Upstream (Macro Factors) Determinants of Health Government

(social, physical, economic, environmental) Education

Policies

Economic Global Forces

Welfare Health Housing

Transport Taxation

Employment Occupation

Income Working Conditions Housing & Residence Area

Midstream (Intermediate) Factors Psychosocial Factors stress

perceptions

demand

networks

depression

expectations

social support

coping

attachment

control

self esteem

anger

Health Care System Access Availability Affordability Utilisation

Health Behaviours Nutrition

Self Harm

Smoking

Alcohol

Preventive Care

Activity

Priority Groups low income low education Indigenous unemployed

Life Stages infants children adolescents adult elderly

Settings & Contexts employment home clubs community education

Ecological models of health and behaviour  If our goal is to generally improve health, we need to look beyond behaviors, and ecological models can play a role  Can we really improve behavior and health when we ignore known environmental and policy influences?

 Psychosocial + Ecological models of health and behavior

Which factors are more likely to explain the obesity epidemic? “Psychosocial” explanation  Less knowledge of relation to diet to health  Lower self-efficacy for walking  Less use of processes of change for diet  Less social support for physical activity etc

“Environmental” explanation  Increased food serving sizes  Building more homes where you must drive for all purposes  Increased availability of fast foods  More TV‟s, DVD‟s, computers, game boys  Subsidies for cars & foods  Less physical activity etc

Studying characteristics of environments relevant to health e.g. neighborhoodlevel measurement

Why study neighborhood characteristics and relationships to health?  Neighborhood environments shape social interaction patterns and determine, in part, resources available to residents and stressors to which they are exposed.  Neighborhood-level social and physical environments (i.e., availability of goods and services) may affect residents above and beyond their individual characteristics.

Melnick, A.L. (2002).

Introduction to geographic information systems in public health. Gaithersburg, Maryland: Aspen Publications.

Geographical Information System (GIS)  Geocodes linked with point (e.g., latitude and longitude of individuals‟ addresses) and theme (e.g., poverty level of neighborhoods/census tracts) data  Data displayed as layers on maps

 Used to visualize database and create measures of health (density and proximity)

Neighbourhood characteristics in relation to socioeconomic status and nutrition (Turrell, Oldenburg et al.)

Model being tested Multi-level factors influencing purchasing behaviour

SES

Environmental Economic & Material Inter-personal Intra-personal

Food Purchasing Behaviour

Food & nutrient intake

Health Status

Relationships being examined in our research Measures reported in this presentation

1

Relationships established or more extensively examined on the basis of previous research

Healthy Food Purchasing

Quantity Type

Size

Opening Transport hours

Private Public

Type Coverage Frequency

FOOD SHOPS

MICRO LEVEL

MACRO LEVEL

Characteristics of the neighbourhood environment

Availability

Variety

Quality

NUTRITIOUS FOODS Healthier choices

Regular choices

Prices

Multi-level determinants of food purchasing behaviour Level

Food Purchasing Related Data

Environmental Objective

Actual accessibility, location & availability of food shops and healthy food, public transport, proximity of shops & houses, number & types of shops, availability & pricing of healthy foods

Subjective Individual

Perceptions of: accessibility, availability & location of food shops, availability of health food, food prices, accessibility to public transport

Inter-personal

Relative influence of household members to food purchasing, demographic profile of household

Intra-personal

Attitudes, concerns, beliefs, knowledge, preferences,

Sample Stratified multi-stage cluster sample of private dwellings in Brisbane City

1517 Census Collectors Districts (CCDs) ranked according to Index of Relative Disadvantage Score (range 547-1200)

Distribution divided into 10 strata

5 CCDs selected from each strata

20 dwelling units randomly sampled from each of the 5 CCDs Final sample: 50 CCD, 1000 households

Map showing sampled census collector‟s districts

Map showing identified food shops and three catchment areas

See next slide

Map showing one catchment area, defined from the centroid of one census collector‟s district

Summary of findings  Significant associations between each socioeconomic indicator and food purchasing e.g. fruit and vegetables (Turrell, et al, J. Human Diet. & Nutrition, 2002)

 Methodological advances (Turrell et al, J. Pub. Health Nut., 2003)

 Differences in spatial neighbourhood characteristics between communities and countries (Turrell, et al, J. Epidem & Community Health, 2004)

 Implications for interventions and policies etc (Oldenburg et al, Medical Journal of Australia, 2000)

Measurement of other environments    

Schools Primary care setting Other health care settings Worksites

Healthy Work Environment Intervention Model

Physical Environment EXERCISE

HEALTHY EATING Information Environment Policy Environment

ALCOHOL

SMOKING Harris, 1996

New questionnaire  CHEW - Checklist of Health Promoting Environments at Worksites  Oldenburg et al, American Journal of Health Promotion, 2002.  Audit of the workplace setting/environment combined with key informant interviews

Domains, risk behaviors & locations covered by CHEW DOMAINS

RISK BEHAVIORS

ENVIRONMENTAL CHARACTERISTICS

Physical environment

Nutrition Activity Smoking Alcohol

canteens, vending machines gym equipment, showers cigarette machines drinking areas

Information environment

Nutrition Activity Smoking Alcohol

Posters about healthy food posters about exercise anti-smoking signs/posters safe-drinking signs/posters

Neighborhood and surroundings

Nutrition Activity Smoking Alcohol

local shops, food outlets local gyms, facilities. cigarette outlets bars and bottle shops in the area

 There are new methods and models for researching the ways in which micro- and more macro-level features of the environment impact on individual‟s health behaviours and health.

Genetic & Biological Foundations and Individual Predispositions

Life-course exposures & development of risk or protective behaviours

Pregnancy

Social, Economic, Policy Environment etc …

Child’s family Adult Education/ Work Partner

Own Family

Independent family

Peer Group School Child care Family of Origin Immediate Community/ Neighbourhood Early Middle Adolescence childhood childhood

Early adulthood

Middle adulthood

Older Adulthood …

Genetic & Biological Foundations and Individual Predispositions

Life-course exposures & development of risk or protective behaviours

Pregnancy

Social, Economic, Policy Environment etc …

Child’s family Adult Education/ Work Partner

Own Family

Independent family

Peer Group School Child care Family of Origin Immediate Community/ Neighbourhood Early Middle Adolescence childhood childhood

Early adulthood

Middle adulthood

Older Adulthood …

Genetic & Biological Foundations and Individual Predispositions

Life-course exposures & development of risk or protective behaviours

Pregnancy

Social, Economic, Policy Environment etc …

Child’s family Adult Education/ Work Partner

Own Family

Independent family

Peer Group School Child care Family of Origin Immediate Community/ Neighbourhood Early Middle Adolescence childhood childhood

Early adulthood

Middle adulthood

Older Adulthood …

A Model of Causation of Morbidity and Mortality Genetics 30% Social Factors 15% Environ Exposures 5% Behaviors 40% Medical Care 10%

Diseases

Morbidity And Mortality

Estimates of mortality impact from McGinnis Williams-Russo, & Knickman. Health Affairs, 2002, 21, 78-93

A Model of Causation of Morbidity and Mortality Biological Interventions

Genetics 30% Social Factors 15% Environ Exposures 5% Behaviors 40%

Medical Care 10%

Diseases

Morbidity And Mortality

A Model of Causation of Morbidity and Mortality Biological Interventions PsychoSocial Interventions

Genetics 30% Social Factors 15% Environ Exposures 5% Behaviors 40% Medical Care 10%

Diseases

Morbidity And Mortality

A Model of Causation of Morbidity and Mortality Biological Interventions PsychoSocial Interventions

Genetics 30% Social Factors 15% Environ Exposures 5%

Macro-Level Environ And Policy Interventions

Behaviors 40% Medical Care 10%

Diseases

Morbidity And Mortality

Complementary Approaches to Prevention

Individual Behaviour Change

Healthy eating Healthy activity Healthy weight

Environmental Change Informing policy which decreases the gradient (eg. China salt substitute study, J Hypertension 2007; 25: 2011-18) Adapted from Puska P, 2004