Why should health psychologists care about socioeconomic status?

Karen A. Matthews, Ph.D.

Low education associated with:

• high BP• high cholesterol• high insulin• high 2-hour glucose• ever smoker• low consumption alcohol• physical inactivity• high BMI• history of hysterectomy*• taking medications for chronic conditions*

*ineligible

Matthews et al., Am J Epidemiol. 129: 1132-1144, 1989.

Low education associated with:

• not discussing anger• high (trait) anger• high anger-in• high depression symptoms• low social support • high pessimism

Matthews et al. , Am J Epidemiol. 129: 1132-1144, 1989.

Why should we care about SES?

Selection of study populationsUnderstand limits of generalizability of findingsEvaluation of psychosocial processes that may

mediate or moderate associations between SES and health

Designing targeted interventions on health-damaging processes associated with poor health

Matthews KA: Health Psychology 8:641-648, 1989.

Questions:

1. What is the definition of SES and how is it measured?

2. What are the relationships between SES and health? When does the association start in the life span?

3. Why is SES related to health?

4. What can be done?

Socioeconomic Status: One’s social position linked to both access to resources and prestige in a social hierarchy.

Common Measures: • Education• Occupational rank• IncomeOther Measures:• Wealth (savings, material resources)• Subjective rank• Childhood SES• Income loss/gain

Median Net Worth in 1991 by Monthly Household Income Quintiles for Whites, Blacks, and Hispanics

Household Income White Black Hispanic

All $44,408 $4,604 $5,345

Lowest Quintile $10,257 $1 $645

Second Quintile $25,602 $3,299 $3,182

Third Quintile $33,503 $7,987 $7,150

Fourth Quintile $52,767 $20,547 $19,413

Highest Quintile $129,394 $54,449 $67,435

Eller TJ: Household wealth and asset ownership; 1991. US Bureau of Census, Current Population Reports, P70-34. Washington, D.C.: US GPO, 1994.

Measures can be taken at an individual, neighborhood,

or national Level

Davey-Smith, et al. BMJ. 1992, 304:431-434.

All-Cause Mortality by IncomeNLMS, 25+ years

SMR (O/E)

Rogot, et al. 1992

0

20

40

60

80

100

120

140

White Male Af-Am Male WhiteFemale

Af-AmFemale

<$50005-9,99910-14,99915-19,99920-24,99925-49,999>50,000

Association of CHD among Black and White Women aged 45-54 by State in 1994 against

Race-Specific Educational Attainment

Percent of not-a-high-school graduate

CH

D m

orta

lity

(41

0-41

4, 4

29.2

) am

ong

wom

en a

ged

45-

54 (

/100

,000

)

J Womens Health Gend Based Med, 2000; 9: 545-558

Race black white

Chronic Conditions More Prevalent Among Those with <12 Year of Education

NHS, 1989: 65 + years

Arthritis Gout Intervertebral disc dis.

Gastritis Kidney dis. Indigestion

Cerebrovascular dis. Hardening of the arteries Varicose veins

Bunions Psoriasis Visual impairment

Diverticulitis Constipation Goiter

Chronic bronchitis Asthma Hay fever

Cataracts Hearing impairment Speech impairment

Diabetes Anemias Migraine

Chronic Sinusitis Emphysema Abd. Hernia

Abs. Of extremities Paralysis Deformity or orth. Impairment Ulcer

Neuralgia/Neuritis Kidney trouble Ischemic heart dis. Other heart dis. Hypertension

Series 10, No. 129

Odds Ratio of Life Time Psychiatric Disorders from National Comorbidity

Study Comparing Those < 19K and > 70K

1

1.4

1.8

2.2

2.6

Affective Disorder

AnxietyDisorder

SubstanceAbuse

AntisocialPersonality

3 Disorders

Kessler, Arch Gen Psychiatry, 1994

Explanations for SES-Health Link

• Poor health causes lowering of SES• Poverty is all that matters• Poor quality health care• Toxic environments • Low intelligence• Adverse health behaviors• High stress environments • Low resources

Risk of Subsequent Income Loss (<$25K) in Depressed (> 16 CES-D) Compared

with Non-depressed Participantsin CARDIA (N=2781)

OR (95% CI) P

White Men 2.4 (1.0 – 5.5) 0.05

White Women 2.2 (1.0 – 4.6) 0.05

African American Men 3.1 (1.5 – 6.6) 0.003

African American Women 1.8 (1.0 – 3.3) 0.05

Whooley et al., Annals of Internal Medicine, in press

Psychol Bull 128:295-329, 2002

0

3

6

9

12

15

18

1 2 3 4 5

Any limiting chronic condition

Asthma prevalence

Ear disease

Injury

Physical inactivity

Prevalence of Health Problems in Children

SES (lowest to highest)

Per

cen

tag

e

Is the association between educational attainment and adult health due in part to poor health in childhood limiting achievement?

Children’sHealth

Children’sEducation

Duration & Quality

Adult Health

Risk

Parental Education

Low education of mother associated with:

• Low birth weight in Whites, Blacks, American Indians or Alaska Natives, not Hispanics

• Teenage births in all groups

• No prenatal care during first trimester in all groups

Health, United States, 1998, with Socioeconomic Status and Health Chartbook

Relationships between SES in Childhood and Health at 26 years: Dunedin Birth Cohort

SES

Adult health Child Adult Social Origin

Physical:

BMI

Waist/hip ratio

SBP

V02 max

Dental:

Tooth cleanliness

Dental caries > 4

Mental:

Major depression

Alcohol dependency

Tobacco dependency Lancet 2002; 360:1640-1645

Variations in Age-26 Health Outcomes as a Function of Alcohol Dependence and Waist:Hip Ratio

0

5

10

15

20

25

30

High Downwardmobility

Upwardmobility

Low76

78

80

82

84

High Downwardmobility

Upwardmobility

Low

% Alcohol Dependence Mean Waist:Hip Ratio

Lancet 360:1640-1645, 2002

Adjusted Hazard Ratios for Low Relative to High SES for CVD Mortality

in Alameda County Study

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

Haz

ard

Rat

io

ChildhoodSES

Education Occupation Income

Beebe-Dimmer: Am J Epidemiol 159:481-490, 2004.

Only in America…

The Reserve Capacity Model

Low SES

Access to

resources

Position in

social

hierarchy

Risk for

atherosclerosis

and

CHD

Threat of

or actual

loss/harm

Potential

for or

actual benefit/

gain

Reserve

Capacity

Tangible

Interpersonal

Intrapersonal

Negative

emotion and

cognition

Positive

emotion and

cognition

TimeC

A

B

D

E

Gallo & Matthews. Psychol Bull 129:10-51, 2003.

Reserve

Capacity

Tangible

Interpersonal

Intrapersonal

What is Reserve Capacity?Resource bank containing:

• Tangible, e.g., financial and material goods.

• Interpersonal, e.g., availability of social support, positive relationships.

• Intrapersonal, e.g., cognitive and social skill, sense of mastery, positive expectations.

Confronting Adversity

• Fewer resources associated with greater susceptibility to negative effects of adversity.

• Experiencing the negative effects of adversity leads to further depletion of resources or to not adding further to the resource bank.

Correlations between SES Indices, Ethnicity, and Life Events Categories among Children

Life Events Category Income Assets Ethnicity:

Black=1 White=0

Discrete, Negative, Independent

-.16* -.30**** .30****

Discrete, Ambiguous, Independent

-.29*** -.25*** .38****

Chronic, Negative, Independent -.17** -.24*** .10

Negative, Non-Independent -.17** -.24*** .21**

Positive, Non-Independent -.02 -.02 .02

Total -.28*** -.34**** .34****

J Ped Psychol 27:575-583, 2002

Negative Interpretations as a Potential Factor in SES-Health Link• Low SES persons grow up in

unpredictable, stressful environments.

• This may lead to a propensity toward interpreting the world as a threatening place that requires constant vigilance.

• Thus, low SES persons may interpret a wide range of stimuli, including ambiguous ones, as potentially threatening.

Negative Outcome:• A popular girl walks up to you and asks why you didn’t

attend her party last night. You hadn’t known there was a party. This girl tells you that she told another classmate of yours to tell you about the party

Ambiguous Outcome:• You are shopping and a clerk asks to take your back pack and count the clothing

articles that you will try on. The security guard and clerk chat and the clerk asks if you would like to keep anything. You say no and start toward the door. The clerk puts your articles back on the rack and stops abruptly, asking the guard where you are.

How do you think it happened that this person…?How would you feel in that situation?

Correlations among SES, Interpretations and Cynical Attitudes SES & Negative

Interpretations SES & Anger

Negative Interpretations &

Cynicism

Ambiguous 1

Ambiguous 2

-.31*

-.29*

-.32*

-.41**

.35**

.40**

Negative 1

Negative 2

-.14

-.20

-.16

-.20

.16

.17

Chen & Matthews, 2001.

*p < .05**p < .01

Mean SBP among Adolescents with Negative Interpretation Scores

SB

P

123

124

125

126

127

128

no one parents otherrelatives

friends schoolpersonnel

Mean Night Time Heart Rate

67

68

69

70

71

72

1 2 3 4

Quartile of Negative Interpretation Scores

HR

Mean Ambulatory SBP by Neighborhood Percent of Poverty

122

123

124

125

126

127

128

129

130

131

Low SES Medium SES High SES

SB

P

What can be done?

• Direct effects on SES thru enhanced education, job training, redistributions of income

• Indirect effects on pathways:

• Health behaviors

• Sense of purpose and commitment

• Stress exposure and coping

Summary

1. SES is a multi-dimensional construct

2. SES is strongly correlated with health

3. SES associations begin early in life

4. Many reasons why

5. Plausible psychological connections

6. Things can be done.