Early and current socio-economic position and cardiometabolic risk factors in the Indian Migration Study

Childhood Socioeconomic Position and Risk of Cardiovascular Disease in Adulthood: Systematic Review of Evidence From Low- and Middle-Income Countries

INTRODUCTION

Socioeconomic disadvantage in childhood is strongly associated with a higher risk of cardiovascular disease in high-income countries. However, the association in low- and middle-income countries, where childhood poverty remains prevalent, has not been reviewed.

METHODS

The authors systematically searched Embase, MEDLINE, and Global Health databases for articles on the association between childhood socioeconomic position and risk of cardiovascular disease in adulthood in low- and middle-income countries until September 2020. Outcomes included measures of cardiovascular disease, its subclinical markers (e.g., carotid intima-media thickness), and its major risk factors (e.g., hypertension, dyslipidemia, diabetes). Where available, associations were extracted before and after adjustment for socioeconomic position in adulthood. Results were synthesized qualitatively by outcome. The study protocol is registered on PROSPERO (CRD42018086984).

RESULTS

The search returned 3,568 unique abstracts, from which 29 eligible articles from 14 middle-income countries were identified, representing >150,000 participants. The most commonly reported outcomes were cardiovascular risk factors; very few studies reported prevalent measures of cardiovascular disease, and no studies reported cardiovascular disease incidence or mortality. Of the 46 reported associations between childhood socioeconomic position and risk of cardiovascular disease, 8 were inverse, 0 were positive, and 38 showed no clear evidence of association. All articles had high (16/29) or medium (13/29) risk of bias.

CONCLUSIONS

Current evidence from middle-income countries provides little support for an association between childhood socioeconomic position and risk of cardiovascular disease, and evidence from low-income countries is lacking. It would be premature to consider childhood poverty as a target for cardiovascular disease prevention in these settings.

Childhood socio-economic conditions and risk of cardiovascular disease: results from a pooled sample of 14 011 adults from India

Background

South Asians are at an increased risk of premature cardiovascular disease, but the reasons for this are unclear. Poor socio-economic conditions in childhood are associated with an increased risk of cardiovascular disease in many high-income countries and may be particularly relevant to South Asia, where socio-economic deprivation is more prevalent and severe. However, evidence from South Asia is limited.

Methods

We pooled data from two large population-based studies in India to provide a geographically representative and adequately powered sample of Indian adults. We used multilevel linear regression models to assess associations between standard of living index (SLI) in childhood (measured by recalled household assets at age 10–12 years) and major cardiovascular risk factors including adiposity, blood pressure, and fasting blood lipids, glucose and insulin.

Results

Data on 14 011 adults (median age 39 years, 56% men) were analysed. SLI in childhood was inversely associated with systolic and diastolic blood pressure, independent of socio-economic conditions in adulthood, with beta coefficients (95% CIs) of −0.70 mmHg (−1.17 to −0.23) and −0.56 mmHg (−0.91 to −0.22), respectively, per SD increase in SLI in childhood. There was no strong evidence for an association between SLI in childhood and other risk factors of cardiovascular disease.

Conclusions

Poor socio-economic conditions in childhood may contribute to the increased risk of premature cardiovascular disease among South Asians by raising their blood pressure. Elucidating the mechanisms and improving socio-economic conditions for children in South Asia could provide major reductions in the burden of cardiovascular disease.

Cardiometabolic risk profile and diet quality among internal migrants in Brazil: a population-based study

PURPOSE

Studies of migrants can improve understanding of the environmental influence on the risk of chronic diseases. In continental countries, internal migration has been associated with changes in diet and health status. The objective of this study is to assess differences in diet quality and the cardiometabolic risk profile between migrants and the host population.

METHODS

A cross-sectional, population-based study was conducted in the city of São Paulo. The study population included internal migrants, defined as individuals born outside São Paulo city who had lived in the city for ten years or longer. The final population (n = 537) was divided into three groups: natives of São Paulo (45.5%), migrants from the Southeast (26.9%) and migrants from the Northeast (27.5%). The joint interim statement consensus criteria were used for diagnosing MetSyn. Diet quality was estimated using the revised version of the Brazilian Healthy Eating Index (BHEI-R). Comparisons between the data of BHEI-R, cardiometabolic risk factors and MetSyn in migrants and natives were performed using generalized linear models adjusted for confounding factors, respectively.

RESULTS

Southeastern and Northeastern migrants younger than 60 years had a higher average of for whole fruit and oil components, respectively. Northeastern migrants older than 60 years had higher systolic and diastolic blood pressure, atherogenic ratio concentrations, lower HDL-C and were more likely to present metabolic syndrome compared to those born in São Paulo of the same age group.

CONCLUSION

Native and internal migrants from Brazil resident in São Paulo exhibited differences in diet quality and cardiometabolic risk factors.

Independent urban effect on hypertension of older Indians: identification of a knowledge gap from a Study on Global AGEing and Health

Among older Indians, more cardiovascular diseases and risk factors are observed in the city dwellers than in the rural population. Clustering of socioeconomic privileges and consequent obesity in the Indian cities are known to underlie this phenomenon. But, it is unclear whether an independent urban effect exists on age-related ailments, unexplained by concentration of privileges and excess weight in the Indian cities. Hence, we aimed to estimate the independent urban effect on hypertension among older Indians after controlling for these factors. Nationally representative data of Indians aged 50 years and older (n = 7273) were collected by Study on global AGEing and health. Hypertension was defined as systolic and/or diastolic blood pressure >139 and > 89 mm Hg, respectively, and/or someone receiving antihypertensive medications. Permanent place of residence (urban/rural) during interview was recorded. Socioeconomic determinants included caste, occupation, assets, and education. Body mass index, abdominal circumference, smoking, alcohol, and physical activity were also controlled. The age- and sex-adjusted odds ratio of hypertension for urban residents was 1.64 (146-1.83), which partially attenuated to 1.22 (1.07-1.38) after controlling for all the covariates. This study highlights 22% excess odds of hypertension among the older Indian city dwellers, unexplained by the greater urban concentration of socioeconomic privileges and obesity. Future research should explore the constituents of this urban effect.

The Association of Levels of and Decline in Grip Strength in Old Age with Trajectories of Life Course Occupational Position

Background

The study of the influence of life course occupational position (OP) on health in old age demands analysis of time patterns in both OP and health. We study associations between life course time patterns of OP and decline in grip strength in old age.

Methods

We analyze 5 waves from the Survey of Health Ageing and Retirement in Europe (n = 5108, ages 65–90). We use a pattern-mixture latent growth model to predict the level and decline in grip strength in old age by trajectory of life course OP. We extend and generalize the structured regression approach to establish the explanatory power of different life course models for both the level and decline of grip strength.

Results

Grip strength declined linearly by 0.70 kg (95% CI -0.74;-0.66) for men and 0.42 kg (95% CI -0.45;-0.39) for women per year. The level of men’s grip strength can best be explained by a critical period during midlife, with those exposed to low OP during this period having 1.67 kg (95% CI -2.33;-1.00) less grip strength. These differences remain constant over age. For women, no association between OP and levels of or decline in grip strength was found.

Conclusions

Men’s OP in midlife seems to be a critical period for the level of grip strength in old age. Inequalities remain constant over age. The integration of the structured regression approach and latent growth modelling offers new possibilities for life course epidemiology.

Living in an urban environment and non-communicable disease risk in Thailand: Does timing matter?

BACKGROUND

This paper uses a life-course approach to explore whether the timing and/or duration of urban (vs rural) exposure was associated with risk factors for NCDs.

METHODS

A cross-sectional survey was conducted among health care workers in two hospitals in Thailand. Two measures of urbanicity were considered: early-life urban exposure and the proportion of urban life years. We explored four behavioral NCD risk factors, two physiological risk factors and four biological risk factors.

RESULTS

Both measures of urbanicity were each independently associated with increases in all behavioral and physiological risk factors. For some biological risk factors, people spending their early life in an urban area may be more susceptible to the effect of increasing proportion of urban life years than those growing up in rural areas.

CONCLUSION

Urbanicity was associated with increases in behavioral and physiological risk factors. However, these associations may not translate directly into increases in biological risk factors. It is likely that these biological risk factors were results of a complex interaction between both long term accumulation of exposure and early life exposures.

The magnitude of obesity and its relationship to blood pressure among the residents of enugu metropolis in South East Nigeria

Background:

Obesity in developing nations is no longer as uncommon as it was thought to be decades ago however paucity of data on the burden of obesity from urban communities was observed by previous workers.

Aim:

To determine the magnitude of obesity and its relationship to blood pressure among urban adult residents in Enugu metropolis.

Subjects and Methods:

A cross-sectional community survey of adults who were not known to have diabetes or hypertension by self-report was carried out. Four parts of the metropolis selected by simple random sampling were used and consenting individuals aged 18-70 years were consecutively recruited. Anthropometric measurements were done using standard procedures as specified in the World Health Organization STEPs instrument. Obesity was determined using widely acknowledged body mass index (BMI) ≥30 kg/m². Descriptive and inferential statistical analyses was performed using SPSS with P value set at <0.05.

Results:

A high prevalence of obesity of 21.2% (95% confidence interval [CI]: 18.3-24.1) was found among the participants with significant female gender preponderance. The burden increased with age with the middle age group highly involved. Attainment of age of 40 years and above had an increased odd of developing obesity (odds ratio = 1.8; 95% CI: 1.3-2.6). There was a relationship between blood pressure and BMI as shown by positive correlation, higher BMI among hypertensive subjects and high burden of elevated blood pressure among obese subjects (91/164; 55.5%).

Conclusion:

A high magnitude of obesity existed among this apparently healthy unaware adults resident in an urban Nigerian city and obesity is associated with elevation in blood pressure.

Palm oil taxes and cardiovascular disease mortality in India: economic-epidemiologic model

OBJECTIVE

To examine the potential effect of a tax on palm oil on hyperlipidemia and on mortality due to cardiovascular disease in India.

DESIGN

Economic-epidemiologic model.

MODELING METHODS

A microsimulation model of mortality due to myocardial infarction and stroke among Indian populations was constructed, incorporating nationally representative data on systolic blood pressure, total cholesterol, tobacco smoking, diabetes, and cardiovascular event history, and stratified by age, sex, and urban/rural residence. Household expenditure data were used to estimate the change in consumption of palm oil following changes in oil price and the potential substitution of alternative oils that might occur after imposition of a tax. A 20% excise tax on palm oil purchases was simulated over the period 2014-23.

MAIN OUTCOME MEASURES

The model was used to project future mortality due to myocardial infarction and stroke, as well as the potential effect of a tax on food insecurity, accounting for the effect of increased food prices.

RESULTS

A 20% tax on palm oil purchases would be expected to avert approximately 363,000 (95% confidence interval 247,000 to 479,000) deaths from myocardial infarctions and strokes over the period 2014-23 in India (1.3% reduction in cardiovascular deaths) if people do not substitute other oils for reduced palm oil consumption. Given estimates of substitution of palm oil with other oils following a 20% price increase for palm oil, the beneficial effects of increased polyunsaturated fat consumption would be expected to enhance the projected reduction in deaths to as much as 421,000 (256,000 to 586,000). The tax would be expected to benefit men more than women and urban populations more than rural populations, given differential consumption and cardiovascular risk. In a scenario incorporating the effect of taxation on overall food expenditures, the tax may increase food insecurity by <1%, resulting in 16,000 (95% confidence interval 12,000 to 22,000) deaths.

CONCLUSIONS

Curtailing palm oil intake through taxation may modestly reduce hyperlipidemia and cardiovascular mortality, but with potential distributional consequences differentially benefiting male and urban populations, as well as affecting food security.

Migration and DNA methylation: a comparison of methylation patterns in type 2 diabetes susceptibility genes between indians and europeans

BACKGROUND

Type 2 diabetes is a global problem that is increasingly prevalent in low and middle income countries including India, and is partly attributed to increased urbanisation. Genotype clearly plays a role in type 2 diabetes susceptibility. However, the role of DNA methylation and its interaction with genotype and metabolic measures is poorly understood. This study aimed to establish whether methylation patterns of type 2 diabetes genes differ between distinct Indian and European populations and/or change following rural to urban migration in India.

METHODS

Quantitative DNA methylation analysis in Indians and Europeans using Sequenom® EpiTYPER® technology was undertaken in three genes: ADCY5, FTO and KCNJ11. Metabolic measures and genotype data were also analysed.

RESULTS

Consistent differences in DNA methylation patterns were observed between Indian and European populations in ADCY5, FTO and KCNJ11. Associations were demonstrated between FTO rs9939609 and BMI and between ADCY5rs17295401 and HDL levels in Europeans. However, these observations were not linked to local variation in DNA methylation levels. No differences in methylation patterns were observed in urban-dwelling migrants compared to their non-migrant rural-dwelling siblings in India.

CONCLUSIONS

Analysis of DNA methylation at three type 2 diabetes susceptibility loci highlighted geographical and ethnic differences in methylation patterns. These differences may be attributed to genetic and/or region-specific environmental factors.