Exposure to the Chinese famine in early life and the risk of anaemia in adulthood

Association of adverse childhood experiences with anemia in older Chinese: Guangzhou Biobank Cohort Study

To examine the association of adverse childhood experiences (ACEs) with anemia among older people. 24,116 participants aged 50 years or above were recruited. Multivariable linear and logistic regression was used to assess the associations of self-reported ACEs number with hemoglobin concentrations (g/dL) and presence of anemia. Older individuals with two or more ACEs, versus no ACEs, showed lower hemoglobin concentrations (β =  - 0.08 g/dL, 95% confidence intervals (CI) - 0.12 to - 0.03) and higher odds of anemia (odds ratio = 1.26, 95% CI 1.01-1.59). A more pronounced association between ACEs and anemia in the lower education group was found, while the association became non-significant in those with higher education (P for ACEs-education interaction = 0.02). ACEs was associated with anemia in older people, and the association was stronger in those with lower education, highlighting the significance of early-life psychological stressors assessment and consideration of education background in geriatric care.

[Multigenerational epigenetic inheritance in human: the past, present and perspectives]

Nowadays, a growing body of evidence suggests that the developmental programs of each individual could be modified. The acquired new phenotypic changes could be persistent throughout the individual's life and even transmitted to the next generation. While the exact mechanism for that preservation is not well understood yet, there are many evidences showing that epigenetic alterations, which are robust and dynamic in response to the influence of the environmental factors, could be responsible for that inheritance. A growing number of external factors such as social stress, environmental pollution and climate changes make adaptation to these environmental changes rather challenging. According to the Developmental Origin of Human Disease theory, formulated by David Barker, environmental conditions experienced during the first phases of development can have long term effects on later phases of life. This phenomenon is linked to the biological plasticity of development, which allows reprogramming of physiological functions in response to different stimuli. Consequently, in utero exposure to environmental pollutants can increase predisposition to different pathologies that can occur both in early and later phases of life not only in the living generation but also in subsequent ones. Here, we have summarised some findings in human epigenetic research studies performed for the past few years which address the question whether transgenerational effects observed in model organisms could also occur in humans.

Association between severe acute malnutrition in childhood and hematological disorders in adulthood: the Lwiro follow-up study in the Eastern Democratic Republic of the Congo

BACKGROUND

Despite growing evidence on the short-term deleterious effects of severe acute malnutrition (SAM) in childhood on hematopoiesis, little is known about the long-term hematological effects of SAM in low-income countries (LICs). Our study explored the association between childhood SAM and hematological disorders in adults 11 to 30 years after post-SAM nutritional rehabilitation.

METHODS

This follow up study investigated 97 adults (mean age 32 years) treated for SAM during childhood in eastern Democratic Republic of the Congo (DRC) between 1988 and 2007. Participants were compared to 97 aged- and sex-matched adult controls living in the same community with no history of SAM. Outcomes of interest were hematological characteristics and disorders in adulthood, assessed by various biological markers. Logistic and linear regression models were used to estimate the association between SAM in childhood and risk of hematological abnormalities.

RESULTS

Compared to the unexposed, the exposed had higher mean white blood cells (/μl) [+ 840 (179 to 1501), p = 0.013], neutrophils [+ 504 (83 to 925), p = 0.019] and platelets (*103) [11.9 (8.1 to 17.9), p = 0.038] even after adjustment for food consumption in adulthood. No difference was observed in red blood cells (RBC), hemoglobin and erythrocytes parameters. With regard to the risk of hematological disorders, in contrast to the unexposed, exposed subjects had a risk of leukocytosis approximately three times higher [adjusted OR (95% CI): 2.98 (1.01 to 8.79), p = 0.048]. No difference was observed in terms of anemia, leukopenia, increased platelets and thrombocytopenia between the 2 groups.

CONCLUSION

Adults with a history of SAM in childhood have hematological characteristics that would be markers associated with chronic low-grade inflammatory or infectious diseases in an environment with no nutritional transition. Larger cohort studies with bone marrow analyses could provide further understanding of the impact of SAM on the overall hematological profile in adult life.

Combined effects of air pollution in adulthood and famine exposure in early life on type 2 diabetes

Famine exposure or air pollution is linked to type 2 diabetes mellitus (T2DM). However, their combined effects on T2DM remain largely unknown. A total of 11,640 individuals were obtained from the Henan Rural Cohort Study. According to their birthdate, participants were divided into three famine exposure subgroups: fetal exposed, childhood exposed, and unexposed groups. The air pollutants (particles with aerodynamics diameters ≤ 1.0 µm (PM₁), ≤ 2.5 µm, and ≤ 10 µm, and nitrogen dioxide) concentrations of each individual were estimated by a spatiotemporal model. Participants were divided into low or high air pollution exposure groups taking the 1st quartile value of air pollutants as the cut-off point. Logistic regression model was used to analyze independent and joint associations between air pollution exposure, famine exposure, and T2DM. Positive associations of air pollution and famine exposure with T2DM were found. Participants who experienced fetal or childhood famine and also were exposed to high concentrations of any kind of the air pollutants had a much higher risk for T2DM than those with no famine and low air pollutants exposure (taking PM_1.0 for example, the odds ratio [OR]: 1.76, 95% confidence interval [CI]: 1.25, 2.47 for fetal famine, and OR: 1.64, 95%CI: 1.13, 2.40 for childhood famine). After stratified analysis, similar results were observed in women. The results indicated that both famine exposure in early life and air pollution exposure in adulthood are related to increased risk for prevalent T2DM, and they have combined effects on T2DM.

Extrinsic and intrinsic factors influencing metabolic memory in type 2 diabetes

Direct and indirect influence of pathological conditions in Type 2 Diabetes (T2D) on vasculature manifests in micro and/or macro vascular complications that act as a major source of morbidity and mortality. Although preventive therapies exist to control hyperglycemia, diabetic subjects are always at risk to accrue vascular complications. One of the hypotheses explained is 'glycemic' or 'metabolic' memory, a process of permanent epigenetic change in different cell types whereby diabetes associated vascular complications continue despite glycemic control by antidiabetic drugs. Epigenetic mechanisms including DNA methylation possess a strong influence on the association between environment and gene expression, thus indicating its importance in the pathogenesis of a complex disease such as T2D. The vascular system is more prone to environmental influences and present high flexibility in response to physiological and pathological challenges. DNA methylation based epigenetic changes during metabolic memory are influenced by sustained hyperglycemia, inflammatory mediators, gut microbiome composition, lifestyle modifications and gene-nutrient interactions. Hence, understanding underlying mechanisms in manifesting vascular complications regulated by DNA methylation is of high clinical importance. The review provides an insight into various extrinsic and intrinsic factors influencing the regulation of DNA methyltransferases contributing to the pathogenesis of vascular complications during T2D.

Concurrency of Early-Age Exposure to Chinese Famine and Diabetes Increases Recurrence of Ischemic Stroke

Background and Purpose: Early age exposure to the Chinese Great Leap Forward famine (1959–1961) is associated with the incidence of risk factors for ischemic stroke. This study aims to examine the relationship between early age famine exposure and 12-month stroke recurrence. We sought to explore the interaction between famine exposure status and metabolic phenotypes on stroke recurrence and how the adherence of crucial evidence-based key performance indicators (KPI) would modify this interaction.

Methods: We analyzed data of patients who were born between 1953 and 1964 in the China National Stroke Registry II (CNSR-II). The study population was further divided into five subgroups for comparing 12-month stroke recurrence. A multivariate Cox proportional hazard regression model was used in analyzing the impact of the concurrence of metabolic phenotypes—type 2 diabetes (T2D) or metabolic syndrome (MetS)—and early-age famine exposure on recurrent risk. The influence of the adherence to predefined KPI and concurrency of metabolic phenotype was also evaluated.

Results: Concurrent T2D and early age famine exposure was associated with an increased recurrence risk of ischemic stroke with 12 months [adjusted hazard ratio (HR): 1.63, 95% confidence interval (CI) 1.28–2.07]. Optimal adherence to KPI was not associated with significantly reduced risk of 12-month stroke recurrence (adjusted HR: 0.80, 95% CI: 0.51–1.26).

Conclusions: Concurrency of early-age famine exposure and diabetes mellitus was associated with a higher risk of stroke recurrence within 12 months, and adherence to evidence-based KPI did not reduce the risk significantly.

Epigenetic variations due to nutritional status in early-life and its later impact on aging and disease

Epigenetics refers to changes in gene function, not resulting from the primary DNA sequence, influenced by the environment. It provides a link between the molecular regulation of the genome and the environmental signals exposed during the life of individuals (including lifestyle, social behavior, development, and nutrition). Notably, early development (intrauterine or postnatal) is highly influenced by the adverse socioeconomic status that leads to malnutrition or obesity; these conditions induce changes over the fetal epigenetic programming and can be transferred by transgenerational inheritance, inducing alterations of the transcription of genes related to several metabolic and neurological processes. Moreover, obesity during pregnancy, and excessive gestational weight gain are associated with an increased risk of fatal pregnancy complications, and adverse cardio-metabolic, respiratory and cognitive-related outcomes of the future child. However, most of our knowledge in this field comes from experimental animal models, that partially resemble the nutritional effects of humans. In this context, nutritional effects implicated in historical famines represent valuable information about the transgenerational effects of undernutrition and stress. In the present review, we attempt to describe the most outstanding results from the most studied famines about the impact of malnutrition on the epigenome.

The impact of early life shocks on human capital formation: evidence from El Niño floods in Ecuador

This paper investigates the persistent effects of negative shocks in utero and in infancy on low-income children's health and cognitive outcomes and examines whether timing of exposure matters differentially by skill type. Specifically, I exploit the geographic intensity of extreme floods in Ecuador during the 1997-1998 El Niño phenomenon, which provides exogenous variation in exposure at different periods of early development. I show that children exposed to severe floods in utero, especially during the third trimester, are shorter in stature five and seven years later. Also, children affected by the floods in the first trimester of pregnancy score lower on cognitive tests. Additionally, I explore potential mechanisms by studying health at birth and family inputs (income, consumption, and breastfeeding). I find that children exposed to El Niño floods, especially during the third trimester in utero, were more likely to be born with low birth weight. Furthermore, households affected by El Niño suffered a decline in income, total consumption, and food consumption in the aftermath of the shock. Falsification exercises and robustness checks suggest that selection concerns such as selective fertility, mobility, and infant mortality do not drive these results.

Birthweight, Type 2 Diabetes Mellitus, and Cardiovascular Disease: Addressing the Barker Hypothesis With Mendelian Randomization

BACKGROUND

Low birthweight has been associated with a higher risk of hypertension, type 2 diabetes mellitus (T2D), and cardiovascular disease. The Barker hypothesis posits that intrauterine growth restriction resulting in lower birthweight is causal for these diseases, but causality is difficult to infer from observational studies.

METHODS

We performed regression analyses to assess associations of birthweight with cardiovascular disease and T2D in 237 631 individuals from the UK Biobank. Further, we assessed the causal relationship of such associations using Mendelian randomization.

RESULTS

In the observational analyses, birthweight showed inverse associations with systolic and diastolic blood pressure (β, -0.83 and -0.26; per raw unit in outcomes and SD change in birthweight; 95% confidence interval [CI], -0.90 to -0.75 and -0.31 to -0.22, respectively), T2D (odds ratio, 0.83; 95% CI, 0.79-0.87), lipid-lowering treatment (odds ratio, 0.84; 95% CI, 0.81-0.86), and coronary artery disease (hazard ratio, 0.85; 95% CI, 0.78-0.94), whereas the associations with adult body mass index and body fat (β, 0.04 and 0.02; per SD change in outcomes and birthweight; 95% CI, 0.03-0.04 and 0.01-0.02, respectively) were positive. The Mendelian randomization analyses indicated inverse causal associations of birthweight with low-density lipoprotein cholesterol, 2-hour glucose, coronary artery disease, and T2D and positive causal association with body mass index but no associations with blood pressure.

CONCLUSIONS

Our study indicates that lower birthweight, used as a proxy for intrauterine growth retardation, is causally related with increased susceptibility to coronary artery disease and T2D. This causal relationship is not mediated by adult obesity or hypertension.

Exposure to the Chinese famine of 1959-61 in early life and long-term health conditions: a systematic review and meta-analysis

Background

Most Chinese people over 55 years old today have experienced the Great Leap Forward Famine of 1959-61. Many reports suggested that the famine could have profound long-term health effects for exposed birth cohorts. A systematic review and meta-analysis was carried out to summarize reported famine effects on long-term health.

Methods

Relevant reports were identified by searching PubMed, Embase, Chinese Wanfang Data and Chinese National Knowledge Infrastructure databases. Long-term health conditions were compared in exposed birth cohorts and unexposed controls. Fixed-effects models and random-effects models were used to combine results on adult overweight, obesity, type 2 diabetes, hyperglycaemia, hypertension, the metabolic syndrome and schizophrenia. The heterogeneity across reports was assessed. Subgroup analyses were carried out using reported famine severity, provincial mortality during famine, sex and other report characteristics.

Results

In all, 36 reports were eligible for systematic review and 21 could be used for meta-analysis. The number of events we analysed ranged from 1029 for hyperglycaemia to 8973 for hypertension. As reported by others, overweight, type 2 diabetes, hyperglycaemia, the metabolic syndrome, and schizophrenia were more common among adults born during the famine compared with controls born after the famine. By contrast, there were no increases in overweight [odds ratio (OR) 0.68; 95% confidence interval (CI): 0.27-1.72], type 2 diabetes (OR 0.96; 95% CI: 0.73-1.28), hyperglycaemia (OR 0.99; 95% CI: 0.72-1.36) or the metabolic syndrome (OR 1.11; 95% CI: 1.00-1.22) comparing adults born during the famine with controls born either after or before the famine. For schizophrenia, the effect estimates (OR 1.60; 95% CI: 1.50-1.70, combining control groups) were similar in the two scenarios.

Conclusions

Our findings suggest that uncontrolled age differences between famine and post-famine births could explain most effects commonly attributed to the famine. For more reliable estimates of long-term famine effects in China, other analyses will be needed with age-appropriate controls and better information on the severity and timing of the famine in the populations included.

PALTEM: What Parameters Should Be Collected in Disaster Settings to Assess the Long-Term Outcomes of Famine?

Evidence suggests that nutritional status during fetal development and early life leaves an imprint on the genome, which leads to health outcomes not only on a person as an adult but also on his offspring. The purpose of this study is to bring forth an overview of the relevant parameters that need to be collected to assess the long-term and transgenerational health outcomes of famine. A literature search was conducted for the most pertinent articles on the epigenetic effects of famine. The results were compiled, synthesized and discussed with an expert in genetics for critical input and validation. Prenatal and early life exposure to famine was associated with metabolic, cardiovascular, respiratory, reproductive, neuropsychiatric and oncologic diseases. We propose a set of parameters to be collected in disaster settings to assess the long-term outcomes of famine: PALTEM (parameters to assess long-term effects of malnutrition).

The relationship between famine exposure during early life and body mass index in adulthood: A systematic review and meta-analysis

Background

Previous epidemiologic studies have reported famine exposure during early life association with overweight or obesity in adulthood, but a consistent perspective has not been established to date.

Purpose

To determine, by conducting a systematic review and meta-analysis, whether exposure to famine could increase body mass index (BMI) in adult or not, and assess the association between famine exposure and the risk of overweight or obesity.

Methods

Published articles were systematically searched (until August, 2017) from PubMed, ScienceDirect, Cochrane, and China National Knowledge Infrastructure. Initially, comparing differences in BMI between exposed and non-exposed groups that weight mean difference (WMD) were used. Subsequently, the effect of famine exposure on overweight or obesity risk, which pooled relative risks (RRs), odds ratios (ORs) or hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated using a random-effects model.

Result

Twenty studies were included in this systematic review and meta-analysis. Compared with non-exposed group, famine exposure group significantly increased the risk of overweight (OR = 1.10, 95% CI: 1.04–1.16) and obesity (OR = 1.15, 95% CI: 1.05–1.24). Sensitivity analyses revealed no significant change in the famine exposure and BMI, the risk of overweight and obesity study when any one study was excluded. Subgroup analyses showed that age, gender, exposure type, study type, continent, famine cause and paper publication date were associated with BMI, the risk of overweight and obesity. Meta-regression analyses suggested that continent, famine cause could partially explain heterogeneity for famine exposure and BMI studies.

Conclusion

The systematic review and meta-analysis indicates that famine exposure during early life may increase BMI, the risk of overweight and obesity, especially for female, fetal famine exposure or subject age less than 50. Furthermore, famine exposure group the risk of overweight and obesity in cross-sectional studies, Asian studies, famine cause by natural disaster or paper published from 2015 to the present studies are higher than that of non-exposed group.

Hb level, iron intake and mortality in Chinese adults: a 10-year follow-up study

Anaemia is prevalent in developing countries and is commonly Fe deficiency related. We aimed to assess the association between Fe status, Fe intake and mortality among Chinese adults. We prospectively studied 8291 adults aged 20-98 years with a mean follow-up of 9·9 years. All participants were measured for Hb at baseline in 2002. Food intake, measured by 3-d weighed food record (n 2832), and fasting serum ferritin were measured. We documented 491 deaths (including 192 CVD and 165 cancer deaths) during 81 527 person-years of follow-up. There was a U-shaped association between Hb levels and all-cause mortality. Compared with the second quartile of Hb (121 g/l), the first (105) and fourth quartile (144) had hazard ratios (HR) of 2·29 (95 % CI 1·51, 3·48) and 2·31 (95 % CI 1·46, 3·64) for all-cause mortality in women. In men, compared with third quartile of Hb (143 g/l), first (122) and fourth quartiles (154) had 61 and 65 % increased risk of all-cause mortality. Anaemia was associated with an increased risk of all-cause and CVD mortality in men but not in women after adjusting for potential confounders. Low and high Fe intake as percentage of Chinese recommended nutrient intake (RNI) were positively associated with all-cause mortality in women but not in men. In women, across quartiles of relative Fe intake, HR for all-cause mortality were 2·55 (95 % CI 0·99, 6·57), 1·00, 3·12 (95 % CI 1·35, 7·18) and 2·78 (95 % CI 1·02, 7·58). Both low and high Hb levels are related to increased risk of all-cause mortality. Both low and high intake of Fe as percentage of RNI was positively associated with mortality in women.

Fetal and infant exposure to the Chinese famine increases the risk of fatty liver disease in Chongqing, China

BACKGROUND AND AIM

Early life exposure to the famine may affect the susceptibility to the metabolic disorders. The objective of this study was to examine the associations of early life exposure to the Chinese Famine (1959-1961) with the risk of fatty liver disease, obesity, hypertension, and hyperglycemia in adulthood.

METHODS

We used the data of 10,935 adults born between 1956 and 1965 in Chongqing from check-up center at the 1st Affiliated Hospital of Chongqing Medical University in 2011. Logistic regression models were used to explore the effects of famine on the risk of fatty liver disease, obesity, hypertension, and hyperglycemia.

RESULTS

In Chongqing, prevalences of fatty liver disease among adults in non-exposed (1956-1958 plus 1963-1965) group and born in 1959, 1960, 1961, and 1962 were 34.01%, 36.42%, 34.63%, 40.27%, and 36.09%, respectively. Prevalences of fatty liver disease, obesity, hypertension, and hyperglycemia were significantly higher in males versus females. The risk of fatty liver disease was about 1.375-fold (1.303 (95% confidence interval, 1.066-1.594) for male, 1.547(95% confidence interval, 1.195-2.002) for female) higher in subjects born in 1961, and 1.142-fold (1.117 (95% confidence interval, 0.957-1.305) for male, 1.242 (95% confidence interval, 1.003-1.537) for female) higher in subjects born in 1962 after adjustment of age and sex, compared with non-exposed subjects. Early life exposure to the Chinese famine was also associated with the increased risk of obesity and hyperglycemia.

CONCLUSIONS

Exposure to the Chinese famine during fetal life and infancy was associated with an increased risk of fatty liver disease in adulthood.

Nutritional determinants of anemia among adults in Eastern China

Historically, Eastern China has the highest prevalence of anemia among adults in China. It is commonly believed that iron deficiency is the main cause of anemia in China. Iron fortified soysauce is used to prevent anemia. Findings from Jiangsu Nutrition Study suggest that diet is related to anemia in this region. However, iron deficiency is not the main cause. Micronutrients other than iron (e.g., riboflavin) need to be considered in the prevention of anemia in the region.

Prevalence and predictors of anaemia in patients with HIV infection at the initiation of combined antiretroviral therapy in Xinjiang, China

Summary

We retrospectively analysed routinely collected baseline data of 2252 patients with HIV infection registered in the National Free Antiretroviral Treatment Program in Xinjiang province, China, from 2006 to 2011 to estimate the prevalence and predictors of anaemia at the initiation of combined antiretroviral therapy. Anaemia was diagnosed using the criteria set forth by the World Health Organisation, and univariate and multivariate logistic regression analyses were performed to determine its predictors. The prevalences of mild, moderate, and severe anaemia at the initiation of combined antiretroviral therapy were 19.2%, 17.1%, and 2.6%, respectively. Overall, 38.9% of the patients were anaemic at the initiation of combined antiretroviral therapy. The multivariate logistic regression analysis indicated that Uyghur ethnicity, female gender, lower CD4 count, lower body mass index value, self-reported tuberculosis infection, and oral candidiasis were associated with a higher prevalence of anaemia, whereas higher serum alanine aminotransferase level was associated with a lower prevalence of anaemia. The results suggest that the overall prevalence of anaemia at the initiation of combined antiretroviral therapy in patients with HIV infection is high in Xinjiang, China, but severe anaemia is uncommon. Patients in China should be routinely checked for anaemia prior to combined antiretroviral therapy initiation, and healthcare providers should carefully select the appropriate first-line combined antiretroviral therapy regimens for anaemic patients.