Ichiro Kawachi

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Verified

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• MD, PhD
• Professor at Harvard University

Importance While many infants with low birth weight (LBW) are eligible for Supplemental Security Income (SSI), more evidence is needed about whether they receive benefits and whether income supports reach infants from the most socioeconomically disadvantaged households. Objective To assess receipt of SSI among LBW-eligible infants (infants eligibl...

Despite progress in legislation protecting the rights and welfare of sexual minorities, homophobic attitudes persist in many societies. To date, research has focused primarily on health consequences for individuals who are the target of homophobic attitudes, but not on those who harbor the prejudice. Using the European Social Survey, we found that...

Background The COVID-19 pandemic was associated with an increase in conspiracy theories worldwide. However, in Japan, the prevalence of COVID-19 conspiracy beliefs has remained unclear. This study aimed to estimate the prevalence and correlates of COVID-19 conspiracy beliefs using a survey of 28,175 residents of Japan aged 16–81 years old. Methods...

Background The Republic of Korea has reported the highest suicide rate globally since 2018. Previous studies have highlighted disability as a significant risk factor for suicide. However, comprehensive examination on the association between suicide mortality and severities and types of disabilities, and on how these associations vary according to s...

We sought to understand the impact of multimorbidity (MM) on the trajectories of functional decline in the last three years of life among older people in Japan. We used nationwide longitudinal cohort data with 6-year follow-up and analyzed 3731 functionally independent residents aged 65 years and older. The primary outcome was the five trajectory g...

Importance Older adults are at high risk for cognitive impairments following natural disasters, but the persistence of such effects is not well understood. Objective To track older adults’ postdisaster cognitive disability trajectories over a decade and examine associations of cognitive disability with disaster damage exposure. Design, Setting, a...

IMPORTANCE Little is known about the spatial accessibility to dental clinics across the US. OBJECTIVE To map the spatial accessibility of dental clinics nationally and to examine the characteristics of counties and US Census block groups with dental care shortage areas. DESIGN, SETTING, AND PARTICIPANTS Cross-sectional study of US dental clinics...

We prospectively examined whether community-level social capital plays a significant role in developing Posttraumatic Growth (PTG) among older survivors of the 2011 Japan Earthquake and Tsunami. The baseline survey was conducted 7 months before the disaster among residents of a city located 80km west of the earthquake epicenter. The survey inquired...

Objectives We examined long-term trajectories of depressive symptoms among older adults following exposure to the 2011 Great East Japan Earthquake and Tsunami. We further characterized the pre- and post-disaster social relationship factors that predicted membership in each trajectory group. Method Data from four time points (including pre-disaster...

This cross-sectional study examines international variations in neonatal mortality rates with and without minimum thresholds for gestational age (22 weeks) and birth weight (500 g) in 2010 and 2020.

Background Relative deprivation is a critical mechanism for understanding how income inequality affects mental health. However, few studies have compared the effects of objective and subjective relative deprivation on health outcomes. This study compared how objective and subjective relative deprivation and their interaction relate to human flouris...

Background Taiso is a Japanese term encompassing meanings akin to calisthenics. Taiso is a widely used exercise program in Japan but whether it prevents functional disability and dementia remains unclear. This study aimed to elucidate the association between practicing Taiso, especially focusing on the well-known Radio-Taiso, and functional disabil...

Importance Millions of adults with low incomes lose Medicaid eligibility when transitioning to Medicare at age 65 years. However, it remains unclear how this transition is associated with dental care. Objective To examine the consequences of transitions from Medicaid to Medicare on coverage and use of dental services. Design, Setting, and Partici...

We examined the associations between the use of different types of media and COVID-19 vaccine hesitancy, as well as risk behaviors of COVID-19 infection, in Japan in late 2021. Cross-sectional surveys were conducted using rapid online surveys of residents in Iwate Prefecture from February 5 to 7, 2021, and from October 1 to 3, 2021. Each individual...

To investigate whether a positive transition into retirement may be associated with later cognitive aging, we included a subset of 4,926 Nurses’ Health Study participants who retired from work at ages 60–69, then provided a subjective assessment of the change in overall quality of life (QOL) with retirement. Subsequently (range: 1 month to 4.7 year...

Background: The COVID-19 pandemic was associated with an increase in conspiracy theories worldwide. However, the prevalence of COVID-19 conspiracy beliefs among Japanese has remained unclear. This study aimed to estimate the prevalence and correlates of COVID-19 conspiracy beliefs in Japan using a nationwide survey of 28,175 residents aged 16–81 ye...

Background Previous studies have shown that job strain is associated with low birthweight (LBW), preterm birth (PTB), and small for gestational age (SGA). We conducted a scoping review and meta‐analysis to assess the association between job strain and adverse pregnancy outcomes. Methods A literature search was performed on PubMed. We included Engl...

Importance Understanding how attachment to pets can alleviate depression and anxiety offers valuable insights for developing preventive and therapeutic strategies, particularly for those with insecure attachment styles from childhood trauma. Objective To determine if a close bond with a pet is associated with reduced depression and anxiety, especi...

Since 2009, China has made large investments in strengthening the primary healthcare system. This study aimed to examine the trends in the number and distribution of health resources in rural China following the health system reform and to decompose the sources of inequalities. Data were collected from standardized reports compiled by each county i...

This study assessed the quality of cause-of-death reporting in the US before and during the COVID-19 pandemic. We used the selection rate and the adjusted odds ratio (aOR) to analyze each cause identified by the National Center for Health Statistics as unsuitable for the underlying cause of death (UCOD). The selection rate was defined as the propor...

Background Loneliness has been implicated as a stroke risk factor, yet studies have examined loneliness at only one time point. The association of loneliness changes and risk of incident stroke remains understudied. Our aim was to examine the association of loneliness with incident stroke, particularly the role of loneliness chronicity. Methods Th...

The COVID-19 pandemic has become and remains a major acute global public health threat. COVID-19 is a severe and complex respiratory disease caused by a highly contagious coronavirus, SARS-CoV-2. The COVID-19 pandemic has transformed everything from daily routines to global supply chains and has had devastating impacts on populations around the wor...

The COVID-19 pandemic has become and remains a major acute global public health threat. COVID-19 is a severe and complex respiratory disease caused by a highly contagious coronavirus, SARS-CoV-2. The COVID-19 pandemic has transformed everything from daily routines to global supply chains and has had devastating impacts on populations around the wor...

This cross-sectional study investigated the association between experiences of discrimination and oral health self-perception among a probabilistic cluster sample of Brazilian adults who participated in the 2013 National Health Survey. Oral health self-perception was categorized into three groups (very good + good; fair; poor + very poor). Reported...

Background Suicide is one of the ten leading causes of death globally, and previous research has revealed a link between economic conditions and mental health. However, the literature has focused primarily on recessions and unemployment, i.e. actual economic developments, as opposed to uncertainty, which relates to economic developments that have n...

Importance Socioeconomic status (SES) is associated with dementia. However, the role of SES transitions in dementia is less explored; such evidence would be useful to understand whether social mobility is associated with healthy longevity at older ages. Objective To investigate the association of lifetime SES transition with risk of dementia. Des...

Introduction Research on the health and economic costs due to insufficient sleep remains scant in developing countries. This study aims to estimate the years of life lost (YLLs) due to short sleep and quantify its economic burden in China. Methods This study estimated both individual and aggregate YLLs due to short sleep (i.e., ≤ 6 h) among Chines...

Introduction Suicide is a global public health problem, and the Republic of Korea has one of the highest suicide rates worldwide. In 2011, the Act on the Prevention of Suicide and the Creation of Culture of Respect for Life (Suicide Prevention Act) was introduced in the Republic of Korea to promote necessary matters for suicide prevention policies....

Background: Research on the health and economic costs due to insufficient sleep remains scant in developing countries. In this study we aimed to estimate the years of life lost (YLLs) due to short sleep and quantify its economic burden in China. Methods: We estimated both individual and aggregate YLLs due to short sleep (ie, ≤6 hours) among Chin...

Importance Racial disparities in sleep health may mediate the broader health outcomes of structural racism. Objective To assess changes in sleep duration in the Black population after officer-involved killings of unarmed Black people, a cardinal manifestation of structural racism. Design, Setting, and Participants Two distinct difference-in-diffe...

Objective: This study examines associations between sleep apnea risk and hypertension in a sample of immigrant Chinese and Korean Americans. Design: The dataset included Chinese and Korean patients ages 50-75 recruited from primary care physicians' offices from April 2018 to June 2020 in the Baltimore-Washington DC Metropolitan Area (n = 394). H...

Background We examined associations between dog ownership, morning dog walking and its timing and duration, and depression risk in female nurses, exploring effect modification by chronotype. We hypothesized that dog ownership and morning walking with the dog are associated with lower odds of depression, and that the latter is particularly beneficia...

Traumatic experiences from disasters have enduring effects on health, both directly and indirectly by influencing health behaviors. Among potential pathways, the impact of disaster-related trauma on dietary patterns has been understudied. This study investigated the relationship between disaster-related trauma and dietary inflammatory index (DII ®...

Introduction Research is beginning to examine the health outcomes of migrators of the Great Migration, a movement of up to eight million African Americans from the South to the North and West during the twentieth century. However, sparse evidence exists studying the health outcomes of the descendants of Great Migration movers. The aim for this stud...

[This corrects the article DOI: 10.2196/42149.].

Background This study aimed to investigate the impact of tobacco industry interference on the implementation and management of tobacco control and the tobacco epidemic using the Tobacco Industry Interference Index (TIII) and MPOWER—a package of measures for tobacco control—and adult daily smoking prevalence in 30 countries. Methods The TIII was ex...

BACKGROUND Health advocates and the media often use the rankings of the leading causes of death (CODs) to draw attention to health issues with relatively high mortality burdens in a population. The National Center for Health Statistics (NCHS) publishes “Deaths: leading causes” annually. The ranking list used by the NCHS and statistical offices in s...

Background The most effective and simple intervention for preventing oral disease is toothbrushing. However, there is substantial variation in the timing of brushing teeth during the day. We aimed to identify a comprehensive set of predictors of toothbrushing after lunch and after dinner and estimated contextual (i.e., geographic) variation in brus...

The relationship between economic recessions and cardiovascular mortality has been widely explored. However, there is limited evidence on whether economic uncertainty alone is linked to cardiovascular disease deaths. This study examines the association between economic uncertainty and mortality from diseases of the circulatory system in the United...

Importance Access to routine dental care prevents advanced dental disease and improves oral and overall health. Identifying individuals at risk of foregoing preventive dental care can direct prevention efforts toward high-risk populations. Objective To predict foregone preventive dental care among adults overall and in sociodemographic subgroups a...

Objective This review comprehensively examines interventions which sought to improve the occupational safety and/or health of construction workers. Factors that explain the (in)effectiveness of interventions were also summarized. Data Source This review consisted of a search using two electronic databases, PubMed and Web of Science. Study Inclusi...

Background Research suggests that people in disadvantaged social positions are more likely to perceive barriers to accessing healthcare, especially to specialists and preventive services. In this study, we analyze if adversity during past employment histories (e.g. spells of unemployment) is linked to subsequent subjectively perceived barriers in h...

We examined whether pre-disaster Sense of Coherence (SOC) mitigated the impact of housing damage on health and well-being of older survivors after the 2011 Japan Earthquake and Tsunami. A panel survey was conducted in a city located 80 km west of the epicenter seven months before and three years after the disaster (3594 respondents). Among responde...

The Great Migration was a movement of roughly eight million Black Southerners relocating to the North and West from 1910 to 1980. Despite being one of the most significant mass internal migrations during the twentieth century, little is known about the health outcomes resulting from migration and whether migrators’ destination choices were potentia...

The extent to which the COVID-19 pandemic has affected early changes in health coverage and access to dental care services in states that expanded Medicaid versus those that did not is currently not well known. Using data from the National Health Interview Survey, we find that during the first year of the COVID-19 pandemic states that had previousl...

Objectives: The sense of coherence refers to effectively using available resources to manage stress and promote overall health. Previous studies have linked it to various health outcomes; however, evidence regarding its association with the risk of incident dementia is limited. Hence, this study aimed to fill this research gap using data from a la...

Background Relative deprivation induced by social comparisons is hypothesised to deleteriously affect health. Previous work has proposed the C R ∼ i index as a measure of relative deprivation; however, the performance of this novel index still needs further testing in the working-age population. This study examined the association of three relative...

Background: Identifying subpopulations that are particularly vulnerable to long-term adverse health consequences of disaster-related trauma is needed. We examined whether child adversities (ACEs) potentiate the association between disaster-related trauma and subsequent cognitive disability among older adult disaster survivors. Methods: Data were fr...

Racial inequities in blood pressure levels have been extensively documented. Experiences of racial discrimination could explain some of this disparity, although findings from previous studies have been inconsistent. To address limitations of prior literature, including measurement error, we implemented instrumental variable analysis (IV) to assess...

Importance: Increasing mortality from suicide, drug overdose, and alcohol-related liver disease (collectively referred to as deaths of despair) is a critical public health crisis. Income inequality and social mobility have been separately associated with all-cause mortality; however, no studies have examined their interaction with these preventabl...

Purpose: Although increasing vaccine uptake is a key strategy to minimize COVID-19 deaths, evidence of the role of vaccination rates in attenuating the socioeconomic disparity in COVID-19 deaths is limited. We thus aimed to quantify the extent to which vaccination rates contribute to the association between US county-level poverty rates and COVID-...

Background Previous studies suggest that experience of natural disasters may heighten present bias. Research also suggests that impaired self-control (in particular, heightened present bias) could be linked to delayed-onset post-traumatic stress symptoms (PTSS) among survivors of natural disasters. We examined a hypothesis that the association betw...

Background This study aimed to investigate the impact of tobacco industry interference on the implementation and management of tobacco control and the tobacco epidemic using the Tobacco Industry Interference Index (TIII), and MPOWER—a package of measures for tobacco control—and adult daily smoking prevalence in 30 countries. Methods The TIII was e...

Background: Population-based longitudinal studies on bereaved children and youth's mental health care use are scarce and few have assessed the role of surviving parents' mental health status. Methods: Using register data of individuals born in Sweden in 1992-1999, we performed a matched cohort study (n = 117,518) on the association between paren...

Objectives To estimate the risk of Long COVID by socioeconomic deprivation and to further examine the inequality by sex and occupation. Design We conducted a retrospective population-based cohort study using data from the ONS COVID-19 Infection Survey between 26 April 2020 and 31 January 2022. This is the largest nationally representative survey o...

Background: Many countries have been increasing their state pension age (SPA); nonetheless, there is little consensus on whether retirement affects the risk of cardiovascular disease (CVD). This study examined the associations of retirement with CVD and risk factors. Methods: We used harmonized longitudinal datasets from the Health and Retiremen...

Objective: The Great Migration was a mass movement in the United States during the twentieth century of roughly eight million Black Southerners to the Northeast, Midwest, and West. Despite its significance, little is known about the health outcomes associated with this internal migration. This study assessed the relationship between migration and...

[This corrects the article DOI: 10.2196/45358.].

Study objectives: We sought to examine the bidirectional associations between posttraumatic stress symptoms (PTSS) and sleep quality in a sample of older disaster survivors. Methods: We used 4 waves (2010, 2013, 2016 & 2020) of the Iwanuma Study, which included pre-disaster information and 9-years of follow-up data among older survivors of the 2...

Importance: Bereavement following parental death experienced in adulthood may be associated with suicide over many years, but this risk has received scant attention. Objective: To investigate whether the risk of suicide increases among adult children around the anniversary of a parent's death. Design, setting, and participants: This case-cross...

Introduction: Research is beginning to examine the health outcomes of migrators of the Great Migration, a movement of up to eight million African Americans from the South to the North and West during the 20th century. However, sparse evidence exists studying the health outcomes of the children of Great Migration movers. The aims for this study were...

Objective To reduce premature deaths due to secondhand smoke (SHS) exposure among non-smokers, the Republic of Korea (ROK) adopted changes to the National Health Promotion Act, which allowed local governments to enact municipal ordinances to strengthen their authority to designate smoke-free areas and levy penalty fines. In this study, we examined...

Previous studies have found a link between economic conditions, such as recessions and unemployment, and cardiovascular disease as well as other health outcomes. More recent research argues that economic uncertainty—independently of unemployment—can affect health outcomes. Using data from England and Wales, we study the association between fluctuat...

In weighing the question of whether AJE should accept preprints that have received press coverage, we need to keep in mind three sets of interests: the public interest, the publisher's interest, and the author's interest. During public health emergencies, such as a pandemic, the author's interests (rapid communication of scientific findings to the...

Background and Objectives Fear of falling and falls are common in older adults. However, their associations with natural disaster exposures remain poorly understood. This study aims to examine longitudinal associations between disaster damage with fear of falling/falls among older disaster survivors. Research Design and Methods In this natural exp...

Natural disasters may affect oral health as a result of serious damage to social function and public health. However, no article has systematically summarized the impact of natural disasters on oral health. This review aimed to map the existing literature on the impact of natural disasters on oral health. Targeted literature was searched using PubM...

Childhood adversity is a risk factor for poor health in late life and includes economic hardship and family violence, whose prevalence is high among offspring of military conscripted father. We assessed the association between paternal military conscription (PMC) and paternal war death (PWD) during Second World War and self-rated health (SRH) among...

Background: Alcohol consumption during pregnancy is associated with a range of adverse birth-related outcomes, including stillbirth, low birth weight, preterm birth, and fetal alcohol syndrome (FAS). With more than 10% of women consuming alcohol during pregnancy worldwide, it is increasingly important to understand how racial/ethnic variations aff...

BACKGROUND Alcohol consumption during pregnancy is associated with a range of adverse birth-related outcomes, including stillbirth, low birth weight, preterm birth, and fetal alcohol syndrome (FAS). With more than 10% of women consuming alcohol during pregnancy worldwide, it is increasingly important to understand how racial/ethnic variations affec...

Unlabelled: Few studies have prospectively examined long-term associations between neighborhood socioeconomic status (nSES) and mortality risk, independent of demographic and lifestyle risk factors. Methods: We assessed associations between nSES and all-cause, nonaccidental mortality among women in the Nurses' Health Study (NHS) 1986-2014 (N = 1...

A new concept called complex multimorbidity (CMM) provides a more reliable measure of disease burden than multimorbidity (MM) based on a simple count of diseases, by categorizing diseases by the body system they affect. This study aims to examine associations between sleep measures and CMM among Chinese and Korean Americans in Baltimore-Washington...

BACKGROUND Fetal Alcohol Syndrome (FAS) is a lifelong developmental disability which occurs among individuals with prenatal alcohol exposure. With improved prediction models, FAS can be diagnosed/treated early, if not completely prevented. OBJECTIVE In this study, we sought to compare different machine learning algorithms and their FAS predictive...

Background Fetal alcohol syndrome (FAS) is a lifelong developmental disability that occurs among individuals with prenatal alcohol exposure (PAE). With improved prediction models, FAS can be diagnosed or treated early, if not completely prevented. Objective In this study, we sought to compare different machine learning algorithms and their FAS pre...

Studies have revealed the links between social capital and diet. However, the mediating role of psychological distress in this relationship has been understudied. This study aims to identify direct and indirect relationships between social capital and adherence to the Mediterranean diet among Lithuanian young adults and identify the mediating role...

Background Only few longitudinal studies with high risk of bias have examined relationship between pets and adolescents' mental health. Methods Our prospective cohort study followed depression-free US adolescents aged 12–18, enrolled in the Growing Up Today Study from pet ownership assessment in 1999 to possible occurrence of high depressive sympt...

The coronavirus disease 2019 (COVID-19) pandemic affected the physical and mental health, socioeconomic status, and community behavior of people worldwide. The aim of this retrospective cohort study was to analyze the impact of the COVID-19 pandemic on the oral health and nutritional status of Japanese older adults based on the results of preoperat...

Abstract Objective To estimate the risk of Long COVID by socioeconomic deprivation and to further examine the socioeconomic inequalities in Long COVID by sex and occupational groups. Design We analysed data from the COVID-19 Infection Survey conducted by the Office for National Statistics between 26/04/2020 and 31/01/2022. This is the largest and...

Objectives: While adverse childhood experiences (ACEs) have been shown to be associated with adulthood obesity, less is known about their association with underweight. We examined the associations between parental absence (i.e., a major component of ACEs) and both underweight and excess weight among middle-aged rural community dwellers in Vietnam,...

Objectives Epidemiological evidence linking long working hours and shift work to metabolic syndrome remains inadequate. We sought to evaluate the impact of reducing working hours on metabolic syndrome. Methods We compared the prevalence of metabolic syndrome among male manual workers in a manufacturing company (N=371) before and after the introduc...

This study examined heterogeneity in the association between disaster-related home loss and functional limitations of older adults and identified characteristics of vulnerable sub-populations. Data were from a prospective cohort study of Japanese older survivors of the 2011 Japan Earthquake. Complete home loss was objectively assessed. Outcomes in...

The activation of stress-related neuroendocrine systems helps to maintain homeostasis, but excessive stress can damage body functions. We review current evidence from basic sciences and epidemiology linking stress to the development and progression of metabolic disorders throughout life. Findings from rodents demonstrate that stress can affect feat...

Maintaining healthy behavior, especially in times of crisis like the COVID-19 pandemic, is particularly important for staying healthy. Nutrition is an everyday behavior and along with other health-related behaviors is associated with many health outcomes. The aim of this study was to assess and compare adherence to the Mediterranean diet (MedDiet)...

Background As ecological factors are getting attention as important determinants of suicide, it is important to identify the unit at which the largest variation exists for more tailed strategy to prevent suicide. We examined the relative importance of two administrative levels for geographic variation in the suicide rate between 2014–2016 in Seoul,...

Historically, AJE has played an important role in the development of social epidemiology as a field. To mark the centennial of the Journal we invited commentaries from three sets of authors in which we asked them to reflect on the role of AJE in advancing our understanding of the social determinants of population health and health disparities. Lisa...

Over the past several decades, the incidence of early-onset cancers, often defined as cancers diagnosed in adults <50 years of age, in the breast, colorectum, endometrium, oesophagus, extrahepatic bile duct, gallbladder, head and neck, kidney, liver, bone marrow, pancreas, prostate, stomach and thyroid has increased in multiple countries. Increased...

Background We examined occupational disparities in COVID-19 vaccine hesitancy in Japan. Methods Cross-sectional online surveys were conducted among of residents living in Iwate Prefecture from July 2 to 4 and from October 1 to 3 in 2021 (total n=17,914). Intention to get vaccinated for COVID-19 was assessed by self-report questions. We calculated...

Objectives: Disasters change survivors’ living circumstances, which can affect their happiness. We examined the trends in the association between disaster damage and happiness before and after a disaster. Methods: We analyzed 4,044 participants aged ≥65 years who had experienced the Great East Japan Earthquake in 2011. The baseline survey was condu...