1. Social Determinants Hypertension: A Review of Studies from Jamaica
Trevor S Ferguson, MBBS, DM, MSc, FACP
Senior Lecturer (Epidemiology), Caribbean Institute for Health Research, UWI
Honorary Consultant (General Internal Medicine), UHWI
Caribbean Institute of Nephrology
11th Annual International Conference on Nephrology and Hypertension
January 18 & 19, 2019

2. Introduction
Social factors are now recognized as important contributors to the burden of HTN and elevated BP
Over the last 2 -3 decades, a large body of literature has emerged, documenting associations between HTN and several social factors

3. Globally HTN Prevalence Highest in Low Income Countries
Strong social gradient in global burden of HTN
28% in low income countries to 18% in high income countries
Gradient similar in men and women
Data source: WHO Global Health Observatory data repository

4. Social Factors and HTN in Epidemiological Studies
Social factors associated with HTN include:
Individual level socioeconomic status (SES) – income, education, and occupation
Household SES – household assets (e.g. television, internet, motor vehicles, …)
Neighbourhood SES - physical and social characteristics of communities in which persons live
Levels of psychosocial stress

5. Socioeconomic status and hypertension Leng et al. – Meta-analysis
Recent meta-analysis of 51 studies published in 2015
Overall increased risk of HTN with lower SES
Income - pooled OR 1.19, 95% CI 0.96–1.48 1
Occupation - pooled OR 1.31, 95% CI 1.04–1.64 1
Education - pooled OR 2.02, 95% CI 1.55–2.63 1
Associations were significant in high-income countries
Association more consistent among women
1Pooled OR – lowest vs highest SES groups
Source: Leng et al. Socioeconomic status and hypertension: a meta-analysis; J Hypertens 33:221–229. DOI: /HJH

6. Socioeconomic status and blood pressure Colhoun – Narrative Review
Colhoun et al., 1998 – narrative review; 57 studies from developed countries, 13 studies from developing countries
Overall, lower SES was associated with higher mean blood pressures in developed countries
Stronger & more consistent association in women vs. men
Substantial component of the SES gradient was explained by differences in BMI
In developing countries, direction of association was often different - higher SES being associated with higher BP
Journal of Human Hypertension volume 12, pages 91–110 (1998)

7. Potential pathways by which socioeconomic status may be associated with blood pressure
Source: Colhoun et al. Journal of Human Hypertension (1998) 12, 91–110

8. Hypertension and socioeconomic status Grotto – Narrative Review, 2008
Reported associations between hypertension and several social determinants - occupation, education, urban or rural dwelling, among others
In general, they found that lower SES was associated with higher BP
Current Opinion in Cardiology: July Volume 23 - Issue 4 - p 335–339; doi: /HCO.0b013e c70

9. Hypertension and socioeconomic status Grotto – Narrative Review, 2008
Suggested explanations for differences:
Better awareness of HTN prevention and controls measures among higher SES groups
Low birth weight and higher job strain among lower SES groups
Current Opinion in Cardiology: July Volume 23 - Issue 4 - p 335–339; doi: /HCO.0b013e c70

10. Hypertension and SES in Jamaica

11. SBP
Spanish Town Cohort ( )
Mendez and colleagues
Mean SBP highest in men and women with higher income and lowest among those in the middle income groups
J-shaped pattern in association between income and SBP
Similar pattern for DBP
DBP

12. SBP
For education, distribution of mean SBP and DBP also J-shaped among men
Among women those with college/university level education had lowest SBP
Again, patterns for DBP were similar
DBP

13. EDUCATION
INCOME
INCOME: Prevalence of hypertension showed similar J-shaped distribution by income category for both men and women and for education categories among men
EDUCATION: For women prevalence of hypertension was again lowest among those with college/university education

14. Education and HTN Spanish Town Cohort vs. Jackson Heart Study

15. Education and HTN Spanish Town Cohort vs. Jackson Heart Study
Prevalence of hypertension - adjusted for age and BMI
STC - prevalence highest among men with better education and among women with lower education
JHS – prevalence highest among those with less education for both men and women; statistically significant for women only

16. Educational Health Disparities in HTN from JHLS-II

17. Age-adjusted prevalence of hypertension among men in JHLS-II
Prevalence of hypertension now lowest among those with post-secondary education
Reversal of pattern seen in Spanish Town Cohort; possibly due to epidemiological transition – pattern now more similar to that seen in developed countries
Differences were not statistically significant
Ferguson et at. Frontiers in Cardiovasculat Medicine 2017; doi: /fcvm

18. Age-specific prevalence of HTN by education category women for in JHLS-II
Significant interaction by age
In general, prevalence lower among those with better education;
Highest prevalence varied by age-group – highest among persons with lowest education in the age group, but among those with full secondary education for the age group and those with junior secondary education among those years

19. Early life SES and blood pressure
Jamaica 1986 Birth Cohort
Early life SES and blood pressure

20. Males whose mothers had lower occupation classification had higher SBP
Maternal Occupation at time of birth and SBP at years old in multi-level regression models in 1986 Birth Cohort Study
Variable
Males
Females
 (95% CI)
Maternal occupation
Highly Skilled/Skilled
Reference
Semi-skilled/Unskilled
3.67 (0.49, 6.85)*
1.81 (-0.65, 4.29)
Unemployed
4.81 (1.99, 7.64)**
2.10 (-0.37, 4.39)
Housewife
3.37 (0.64, 6.11)*
1.85 (-0.57, 4.26)
* p<0.05; ** p<0.01; *** p<0.001
In the fully adjusted model, one standard deviation increase in BWT was associated with 1.16 mmHg reduction in SBP among men (95%CI 2.15 to 0.17; p=0.021) and 1.34 mmHg reduction in SBP among women (95%CI 2.21 to 0.47; p=0.003). Participants whose mothers had lower SEC had higher SBP compared to those with mothers of high SEC (β, mmHg for men, p<0.05 for all SEC categories, and for women, p>0.05)
Males whose mothers had lower occupation classification had higher SBP
Association for females not statistically significant
Ferguson et al. (2015) Birth weight and maternal socioeconomic circumstances were inversely related to systolic blood pressure among Afro-Caribbean young adults. J Clin Epidemiol Feb 12. doi: /j.jclinepi

21. Predicted systolic blood pressure by birth weight and mothers occupation category
Male
Female
These figures show predicted SBP by maternal occupation at birth and birth weight z-scores, based on the final SBP model. Among men, there was a consistent gradient in SBP by maternal occupation and birth weight SD distribution, with SBP consistently highest for those whose mothers were unemployed and lowest for those whose mothers were in a highly skilled/skilled occupation. Among women, the trend was less delineated by maternal occupation. SBP was lowest among whose mothers were in a highly skilled/skilled occupation category but there was little difference in SBP between the other groups.
skilled/highly skilled
semi-skilled/unskilled
unemployed
housewife
Ferguson et al. (2015) Birth weight and maternal socioeconomic circumstances were inversely related to systolic blood pressure among Afro-Caribbean young adults. J Clin Epidemiol Feb 12. doi: /j.jclinepi

22. Household SES and blood pressure at age 18-20 years
Jamaica 1986 Birth Cohort
Household SES and blood pressure at age years

23. Factors associated with elevated BP or HTN among males and females in multivariable logistic regression models
Variable
Odds Ratio
95% CI
P-Value
Household possessions
High (15-17 items)
1.0 -
Moderate (10-14 items)
0.62
0.33 – 1.18
0.147
Low (0-9 items)
1.21
0.59 – 2.45
0.604
Variable
Odds Ratio
95% CI
P-Value
Household possessions
High (15-17 items)
1.0 -
Moderate (10-14 items)
4.63
1.31 – 16.4
0.017
Low (0-9 items)
2.61
0.70 – 9.77
0.154
Among females those from households with fewer household assets were more likely to have elevated blood pressure or hypertension
Association among males not statistically significant

24. Neighbourhood SES and BP – Pooled Analysis
1986 Birth Cohort, JHLS-II, JYRRBS
Sa1106

25. Methods
A pooled analysis was conducted using data from 2 national surveys and a birth cohort; combined sample size = 2556
Data on neighbourhood SES were obtained from the Mona GeoInformatics Institute
Community characteristics included poverty, unemployment, dependency ratio, population density, house size, and proportion with tertiary education
Principal component analysis was used to derive community SES scores, then categorized into tertiles

26. Summary statistics for participant characteristics
1986 Birth Cohort
n = 893
Youth Risk Survey
n = 1200
JHLS-II
n = 463
Age (years) ***
18.8 ± 0.44
16.5 ± 0.8
19.8 ± 1.9
BMI (kg/m2) ***
23.0 ± 3.0
22.3 ± 2.3
24.0 ± 5.4
SBP (mmHg) ***
110.4 ± 7.0
111.4 ± 7.1
113.9 ± 10.4
DBP (mmHg) ***
67.9 ± 5.9
70.4 ± 7.1
71.8 ± 7.8
Elevated BP / HTN ***
188 (21.1)
388 (32.3)
173 (37.4)
*** P<0.001
Values are mean ± SD except for elevated BP/HTN which is number and percent
Age range: 1986 Birth Cohort years; Youth Risk years; JHLS-II years
JHLS-II = Jamaica Health and Lifestyle Survey ; BMI = body mass index; SBP = systolic blood pressure; DBP = diastolic blood pressure; BP = blood pressure; HTN = hypertension

27. Map of communities included in the analysis by study and socioeconomic status tertiles
Communities coloured red represent those in the lowest socioeconomic status (SES) tertile, those coloured yellow are in the middle SES tertile and those coloured blue are in the upper SES tertile. Most upper tertile communities are from the urban areas in the parishes of Kingston, St Andrew and St Catherine.

28. Final multivariable models1 for association between SBP for individual and community characteristics
Males
-coefficient (95% CI)
Females
PCA SES Component 1
Lower Tertile
Reference category
Middle Tertile
-2.41 (-4.05, -0.77) **
-1.43 (-2.91, 0.03)
Upper Tertile
-4.08 (-6.04, -2.11) ***
-1.03 (-2.86, 0.80)
PCA SES Component 2
0.11 (-1.73, 1.95)
2.59 (0.95, 4.21) **
0.25 (-1.54, 2.05)
1.51 (-0.19, 3.21)
Household Possessions
-1.29 (-2.78, 0.20)
-0.56 (-1.67, 0.55)
-0.88 (-2.47, 0.72)
-1.44 (-2.68, -0.19) *
*p<0.05; **p<0.01; ***p<0.001
1Separate models computed for males and females
PCA-SES1 – higher value = higher SES; Males with higher SES had lower SBP
PCA-SES2 – higher value = lower SES; Females with lower SES had higher SBP

29. Spike plots with LOWESS mean-smoothing curve for predicted mean systolic blood pressure for each community ranked by PCA derived socioeconomic status (PCA SES component 1) suggest lower SBP with higher community SES
PCA = principal component analysis; A SBP = systolic blood pressure; SES = socioeconomic status
LOWESS = Locally Weighted Scatterplot Smoothing

30. Conclusion
Higher neighbourhood SES was inversely associated with BP among Jamaican youth
There were some significant gender differences in these associations
Findings from this study suggest that the neighbourhood context may be an important factor in the aetiology of hypertension
Interventions to address this growing public health challenges should include evaluation of neighbourhoods
Key References
1. Arcaya MC, Tucker-Seeley RD, Kim R, Schnake-Mahl A, So M, Subramanian SV. Research on neighborhood effects on health in the United States: A systematic review of study characteristics. Social science & medicine (1982) ;168:16-29.
2. Diez Roux AV. Neighborhoods and Health: What Do We Know? What Should We Do? American journal of public health. 2016;106(3):430-1.
3. Diez Roux AV, Mair C. Neighborhoods and health. Annals of the New York Academy of Sciences ;1186(1):

31. Summary and Implications
Consistent evidence for a relationship between hypertension and SES
Findings vary by sex and SES measure used
More research needed to clarify associations and work out mechanisms
Given general relationship between poor social circumstances and health, interventions to improve living conditions and social status are needed.

32. QUESTIONS / DISCUSSION
THANK YOU
QUESTIONS / DISCUSSION