Migration, nativity and cultural orientation as predictors of decline in cognitive status, incidence of dementia/CIND and all cause mortality in The Sacramento Area Latino Study on Aging

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Migration, nativity and cultural orientation as
predictors of decline in cognitive status,
incidence of dementia/CIND and all cause
mortality in The Sacramento Area Latino Study
on Aging

• Mary N. Haan, MPH, DrPH, Vivian Colon Lopez, MPH,
  Hector M Gonzalez, PhDKala Mehta, DSc Ladson
  Hinton, MDUniversity of Michigan, School of
  Public Health, EpidemiologyUniversity of
  California San Francisco, School of Medicine,
  Geriatrics University of California, Davis,
  School of Medicine, Psychiatry

Funding NIA AG 12975 1997-2008 NIDDK DK 60753,
AG10129, AG10220 USDA 00-35200-9073
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History of the Mexico-US Border and migration

• Fluctuations in
• Immigration policy and practice
• Economic and political motivations for migration
• Economic demand for cheap labor in agriculture
• Crossing Borders is not synonymous with
  cultural change Often borders change leaving
  people in place

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Why would migration influence health in old age?

• Early life exposures
• Social, cultural and socioeconomic
• Physical environmental, nutritional, infectious
• Transitions
• Cultural changes Acculturation
• Socioeconomic advances (or not)
• Differences in exposures to risk factors
• Environmental
• Behavioral
• Social
• Changes in exposures
• Timing of exposure early life vs later life
• Age-related effects of exposure at early vs later
  life

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Cultural orientation

• Acculturation
• - Adoption of behaviors/beliefs of culture in
  new country/location
• Immigration ? change in cultural orientation
• US born
• Socioeconomic status (SES), diversity of
  community (mono-ethnic vs. poly ethnic)
• Foreign born
• SES, timing of education, community,
  discrimination
• Defining cultural orientation
• Typical language, contact with own ethnic group
  vs. others, celebration of traditions
• Cultural flexibility ability to cross cultural
  boundaries
• Not synonymous with nativity

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Socioeconomic status a major predictor of health
and death in all populations

• SES and immigration
• Attainment of higher SES
• Age at migration (post-migration education)
• Education before and after migration
• Success in overcoming discrimination to improve
  status
• Languages spoken/learned
• Education vs. financial status
• Which is more influential for health?

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Sacramento Area Latino Study on Aging Cohort
Study

• Study Population
• 1,789 Latinos aged 60, primarily Mexican
  ancestry (85)
• 49 US born and 51 Mexico or another Latin
  American country
• 58.3 female
• Mean age at baseline 71 (60-101)
• 51 Spanish speaking
• Study period
• Baseline 1998-99
• Annual follow-up through 2008
• Semi annual phone interviews
• In home clinical evaluations and interview
• Cognitive testing, clinical assessments
• Socio-demographic factors
• Medical history

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Analysis questions

• Is there a difference by nativity for
• All cause mortality?
• Cognitive decline?
• Incidence of dementia combined with cognitive
  impairment without dementia (CIND)?
• Is cultural orientation associated with these
  outcomes?
• Are the associations between nativity or cultural
  orientation influenced by SES?

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Approach to analysis of 4-year follow-up

• Mortality or dementia/CIND
• incidence
• Non parametric survival analysis (life tables)
• Proportional hazards models
• Lost to follow-up treated as alive or as non
  demented
• Effect modification
• Adjustment for confounding

• Change in cognition
• Mixed linear models
• Testing for model fit with AIC
• 3MSE errors
• Log(101-3mse)
• Effect modification
• Adjustment for confounding

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Key Outcome Measures (four years)

• Mortality
• Ascertainment via multiple reports, NDI, vital
  statistics
• (n317 deaths 52 in US born)
• Dementia/CIND
• 3-stage evaluation process including screening,
  clinical evaluation and case adjudication using
  standard criteria
• (N111 36 in Mexican/Latin born)
• Cognitive change
• Modified Minimental State Exam (3MSE)

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Key exposure measures

• Nativity
• Country of birth (US, Mexico, Other Latin
  American)
• Cultural orientation
• Cuellar scale language, contact, friendships
• Sum of items (0-54), Alpha 0.88
• Health at baseline
• Stroke
• Type 2 diabetes
• Health insurance and source of medical care

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Key exposures Coding for socioeconomic status
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Part 1 Culture, immigration, health and
socio-demographic factors
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Socio-demographic and health differences by
nativity at baseline

• Higher in Mexican/Latin-
• Age 71 vs. 70
• Spanish speaking 89 vs. 31
• Fair or Poor Self rated health 57 vs. 41
• No medical insurance 16 vs. 2.5
• Residence in Latino neighborhood 42 vs. 28
• Main occupation in agriculture

• Higher in US-
• Mean years of education 9.6 years vs. 5.0 years
• Own your home 78 vs. 56
• Mean cultural scale 31 vs. 14
• Prevalence () of type diabetes 33 vs. 25
• Prevalence () of stroke 12 vs. 7

Significant differences only
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Mean years of education by total household
income by country of birth
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(No Transcript)
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Cultural orientation by SES and nativityfrom an
ANOVA including SES, nativity, gender, and age




Significant (plt.0001) by nativity
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Conclusions Part 1

• US born have higher education at every income
  level than Mexican/Latin born
• Mexican/Latin born are disproportionately in the
  lowest education and income group
• Cultural score increases with income and
  education
• Cultural score is lower for Mexican/Latin born at
  every level of SES vs. US born

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Part 2 All cause mortality
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All cause 4-year mortality by nativity and gender
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Predictors of all-cause mortality by gender in
SALSAfrom proportional hazards models with
simultaneous adjustment(only significant at
plt0.01 shown)
Reference for SES low income, low education
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Nativity and all cause mortality by gender and
agefrom proportional hazards models stratified
on gender
Adjusted for age, gender, nativity, SES,
diabetes, stroke, agenativity
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Part 2 Conclusions mortality

• There are no overall differences in mortality by
  nativity among men
• Women born in Mexico/Latin America have lower
  mortality risk than women born in US
• This advantage disappears with age so that older
  Mexican born women have higher mortality risk
  than older US born women
• Age, SES and health are major predictors of
  mortality independent of nativity and do not
  influence the association

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Part 3 Cognitive decline
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Change in Errors on the Modified Minimental State
Exam (3MSE) over 4 years by nativity and for a 1
SD difference in cultural orientation from an
adjusted mixed linear model
Age, gender, SES, diabetes, stroke p value for
timenativity 0.03
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SES as a predictor of change on the 3MSE from an
adjustedmixed linear model
Adjusted for age, gender, nativity, stroke,
diabetes, timeSES, P interaction0.005
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Part 3 Conclusions Cognitive Decline

• Errors on the 3MSE increased among those born in
  Mexico/Latin American increased more rapidly than
  among those born in the US
• A 1 SD difference (12 points) on the cultural
  scale was associated with an average increase in
  errors on the 3MSE of 2 points
• Those with low education and income had more
  errors on the 3MSE that persisted over 4 years
• Those with higher education, regardless of income
  or nativity, had fewer errors

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Part 4 Dementia/CIND incidence
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Risk of dementia/CIND and cultural orientation by
tertiles from adjusted proportional hazards
models
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Risk of dementia/CIND associated with 1 SD
difference in cultural score by nativity from
stratified proportional hazards models
(0.52-0.78)
(0.94-1.01)
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Predictors of dementia/CIND incidence in
SALSAfrom a proportional hazards model with
simultaneous adjustment
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Risk of dementia/CIND associated with combined
income and education in study participants from
proportional hazards models
Adjusted for age, gender, stroke, diabetes
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Part 4 Conclusions dementia/CIND

• Anglo cultural orientation is associated with a
  lower risk of dementia/CIND, even after
  adjustment for SES
• Anglo cultural orientation is associated with a
  lower risk of dementia/CIND among Mexican born
  but not among US born
• Older age, lower SES, presence of diabetes,
  stroke are associated with higher risk of
  dementia/CIND
• Nativity is not associated with incidence of
  dementia/CIND
• Higher education is associated with lower risk of
  dementia/CIND regardless of income

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Final Conclusions

• Nativity is not associated with mortality overall
• Aging may modify the risk of death among women so
  that the Mexican/Latin advantage disappears with
  increasing age
• Among Mexican/Latin born, dementia risk is lower
  for those with more Anglo orientation
• Lower socioeconomic status increases risk of
  outcomes regardless of nativity