Rapid weight change as a predictor of disability among community-dwelling Japanese older adults.

AIM: To fill the knowledge gap regarding weight change and the onset of disability in community-dwelling Japanese older adults, we investigated the potential effects of rapid weight change on disability risk as defined by Japan's long-term care insurance (LTCI) system. METHODS: We analyzed data from a longitudinal study of 10 375 community-dwelling older Japanese adults (≥65 years) who were not LTCI needs certified at baseline and joined the study from 2002 to 2005. Weight change (percentage) was calculated by subtracting participants' weight in the previous year from that measured during a physical examination at study commencement. The five weight-change categories ranged from sizable weight loss (≤ -8.0%) to sizable weight gain (≥ +8.0%). Disability was defined according to LTCI certifications at follow-up. Hazard ratios (HRs) and 95% confidence intervals were calculated for new-onset disability using a Cox proportional hazards model that fitted the proportional subdistribution hazards regression model with weights for competing risks of death. RESULTS: During the mean 10.5-year follow-up, 2994 participants developed a disability. Sizable weight loss (HR [95% confidence intervals], 1.41 [1.17-1.71]) and weight loss (1.20 [1.05-1.36]) were significant predictors of disability onset. Sizable weight gain (1.45 [1.07-1.97]) corresponded to severe disability. Stratified analyses by lifestyle and initial body mass index categories revealed more pronounced associations between weight change and disability risk in the unhealthy lifestyle and below initial normal body mass index groups. CONCLUSIONS: Rapid and sizable weight gain could be additional criteria for disability risk in older adults. Geriatr Gerontol Int 2023; 23: 809-816.

Occupational disparities in COVID-19 vaccine hesitancy in Japan.

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 odds ratios for vaccine hesitancy among occupational groups using logistic regression models controlling for covariates and stratified by age and sex groups. Results: The overall prevalence of vaccine hesitancy was 5.5% in our sample of working-age adults. Women <40 years were also 1.6 times more likely to be vaccine hesitant, citing concerns about adverse effects on pregnancy or breastfeeding. Among people aged 40-59 years, workers in the service industry, manufacturing industry, and the unemployed were significantly more likely to have perceived vaccine hesitancy regardless of sex. Young service workers viewed themselves as being more vulnerable to risk of infection but less susceptible to getting severe disease, whilst exhibiting low levels of vaccine knowledge. Middle-aged (40-59 years) workers in the manufacturing industry underestimated both vulnerability to infection and disease severity, as well as demonstrated low knowledge of vaccines and practice of preventive measures. Conclusions: While complex and heterogeneous reasons for COVID-19 vaccine hesitancy have been cited in Western countries (e.g., mistrust of government, medical mistrust, and conspiracy beliefs), the situation in Japan may be more amenable to educational interventions targeting specific occupations. Policymakers should target interventions for increasing vaccine readiness in high risk occupations.

A high level of vaccine knowledge increases people's behavioral risks for contracting COVID-19 in Japan.

BACKGROUND: There has been no study in which the association between levels of vaccine knowledge and preventive behaviors was examined during the COVID-19 pandemic. We examined the transition to risky (transmission) behavior according to level of vaccine knowledge over a seven-month period when vaccines became widely available in Japan. METHODS: A series of cross-sectional surveys were conducted using rapid online surveys of residents in Iwate Prefecture from December 4 to 7 in 2020 (the first survey) and from July 2 to 4 in 2021 (the fourth survey). We calculated each individual's risk of acquiring SARS-CoV-2 infection using a quantitative assessment tool (the microCOVID calculator). The respondents' level of knowledge regarding the COVID-19 vaccine was assessed by a questionnaire and was divided into four groups: very low level, low level, moderate level, and high level of vaccine knowledge. RESULTS: People with a high-level knowledge about the vaccine had significantly higher odds ratios (ORs) of transitioning to high-risk behavior compared to people with a low level of vaccine knowledge (OR [95% confidence interval (CI)], 1.50 [1.17-1.93]; P = 0.001). There was a dose-response association according to the four levels of vaccine knowledge, while engagement in preventive measures in the first survey was not associated with high-risk behavior in the follow-up survey. CONCLUSIONS: Since new variants of SARS-CoV-2 have evolved, policy makers should continue to communicate strong messages to keep a high level of consciousness and maintain basic preventive measures even after widespread vaccination.

Risk Factors of Long-Term Care Insurance Certification in Japan: A Scoping Review.

This study aimed to review evidence on future long-term care associated with pre-existing factors among community-dwelling Japanese older adults. We systematically searched cohort and nested case-control studies published between 2000 and 2019 that assessed long-term care certification using the PubMed, CINAHL, and EMBASE databases. The relationship between long-term care insurance information and risk factors was investigated. The protocol was registered with the Open Science Framework. We extracted 91 studies for synthesis, including 84 prospective cohort studies, 1 retrospective cohort study, and 6 nested case-control studies. Certification for long-term care was classified into two endpoints: onset of functional disability and dementia. There were 72 studies that used long-term care certification as a proxy for functional disability, and 22 used long-term care information to indicate the onset of dementia. Common risk factors related to functional disability were physical function, frailty, and oral condition. Motor function and nutritional status were common risk factors for dementia. We found consistent associations between premorbid risk factors and functional disability and dementia. The accumulation of evidence on the incidence of long-term care and associated factors can aid the development of preventive measures. Future studies should aim to integrate this evidence.

Increase in people's behavioural risks for contracting COVID-19 during the 2021 New Year holiday season: longitudinal survey of the general population in Japan.

OBJECTIVES: There has been no study in Japan on the predictors of risk for acquiring SARS-CoV-2 infection based on people's behaviour during the COVID-19 pandemic. The aim of this study was to document changes in risk behaviour during the New Year's holiday season in 2021 and to identify factors associated with high-risk behaviour for infection using a quantitative assessment tool. DESIGN: A longitudinal survey. SETTING: Multiphasic health check-ups for the general population in Iwate Prefecture. PARTICIPANTS: Serial cross-sectional data were obtained using rapid online surveys of residents in Iwate Prefecture from 4 to 7 December 2020 (baseline survey) and from 5 to 7 February 2021 (follow-up survey). The data in those two surveys were available for a total of 9741 participants. MAIN OUTCOME MEASURES: We estimated each individual's risk of acquiring SARS-CoV-2 infection based on the microCOVID calculator. We defined four trajectories of individual risk behaviours based on the probabilities of remaining at low risk, increasing to high risk, improving to low risk and persistence of high risk. RESULTS: Among people in the low-risk group in the first survey, 3.6% increased to high risk, while high risk persisted in 80.0% of people who were in the high-risk group at baseline. While healthcare workers were significantly more likely to be represented in both the increasing risk and persistently high-risk group, workers in the education setting were also associated with persistence of high risk (OR 2.58, 95% CI 1.52 to 4.39; p<0.001). CONCLUSIONS: In determining countermeasures against COVID-19 (as well as future outbreaks), health officials should take into account population changes in behaviour during large-scale public events.

The differences of poor SRH among municipalities in Iwate after the Great East Japan Earthquake.

The health of communities has been observed to recover at differential rates in the wake of disasters. In the present study, the 5-year trends in poor self-rated health (SRH) in three municipalities of Iwate Prefecture following the 2011 Great East Japan Earthquake and Tsunami were compared. Annual surveys were conducted from 2011 to 2015 in three municipalities (Otsuchi, Rikuzentakata, and Yamada) that were heavily damaged by the tsunami. We tracked the prevalence of poor SRH in 10,052 participants (mean age, 61.0 years; 39.0% men). Trends in the prevalence of poor SRH were analyzed using generalized linear mixed effect models with control for covariates. Immediately after the disaster (2011), all three municipalities reported similar prevalences of poor SRH (around 15%). Among people under the age of 65 years, there was a gradual improvement in health for residents of Rikuzentakata and Yamada, but the prevalence of poor SRH remained persistently high in Otsuchi. Among people over the age of 65 years, the prevalence of poor SRH remained constant in Rikuzentakata and Yamada but increased over a 5-year follow-up period in Otsuchi. The delayed health recovery in Otsuchi may be due to the characteristics of the local health system. Examination of the variations in health recovery may provide clues about the sources of disaster resilience.

Low educational level increases functional disability risk subsequent to heart failure in Japan: On behalf of the Iwate KENCO study group.

OBJECTIVES: The risk factors that contribute to future functional disability after heart failure (HF) are poorly understood. The aim of this study was to determine potential risk factors to future functional disability after HF in the general older adult population in Japan. METHODS: The subjects who were community-dwelling older adults aged 65 or older without a history of cardiovascular diseases and functional disability were followed in this prospective study for 11 years. Two case groups were determined from the 4,644 subjects: no long-term care insurance (LTCI) after HF (n = 52) and LTCI after HF (n = 44). We selected the controls by randomly matching each case of HF with three of the remaining 4,548 subjects who were event-free during the period: those with no LTCI and no HF with age +/-1 years and of the same sex, control for the no LTCI after HF group (n = 156), and control for the LTCI after HF group (n = 132). HF was diagnosed according to the Framingham diagnostic criteria. Individuals with a functional disability were those who had been newly certified by the LTCI during the observation period. Objective data including blood samples and several socioeconomic items in the baseline survey were assessed using a self-reported questionnaire. RESULTS: Significantly associated risk factors were lower educational levels (odds ratio (OR) [95% confidence interval (CI)]: 3.72 [1.63-8.48]) in the LTCI after HF group and hypertension (2.20 [1.10-4.43]) in no LTCI after HF group. Regular alcohol consumption and unmarried status were marginally significantly associated with LTCI after HF (OR [95% CI]; drinker = 2.69 [0.95-7.66]; P = 0.063; unmarried status = 2.54 [0.91-7.15]; P = 0.076). CONCLUSION: Preventive measures must be taken to protect older adults with unfavorable social factors from disability after HF via a multidisciplinary approach.

Five-year blood pressure trajectories of survivors of the tsunami following the Great East Japan Earthquake in Iwate.

Whether tsunami survivors who suffered substantial damage experienced increases in blood pressure (BP) immediately after the disaster and in the medium to long term is unclear. We divided tsunami survivors into groups, those who relocated (substantial damage) and those who did not (little damage) and compared the BP trajectories between the groups over the first 5 years after the disaster. Of the 42,831 residents, 3914 were assessed from 2010 to 2015. Subgroup analysis was performed among the 2037 subjects with no information on antihypertensive medications between 2010 and 2015 (no antihypertensive medication group). The BP trajectories in the relocation and no relocation groups were compared using linear mixed models. The multivariate-adjusted mean systolic BP (SBP) values for all subjects significantly decreased after the disaster in both the group who relocated (2010: 130.6 mmHg, 2015: 124.8 mmHg) and the group who did not relocate (2010: 130.7 mmHg, 2015: 126.7 mmHg). The interaction between relocation and time points on SBP was significant (P = 0.017). In the no antihypertensive medication group, the SBP values in the subgroup who relocated were significantly lower in the second, third, and fifth years after the disaster than those in the subgroup who did not relocate. It was concluded that the SBP values of survivors of the tsunami caused by Great East Japan Earthquake decreased in the medium to long term after the disaster, and the group who relocated had a larger decrease in SBP than the group who did not relocate.

Increase in Body Weight Following Residential Displacement: 5-year Follow-up After the 2011 Great East Japan Earthquake and Tsunami.

BACKGROUND: Previous studies have linked residential displacement as a result of the 2011 East Japan Earthquake to increases in body weight. However, no study has examined longer-term trajectories of body weight among displaced survivors. We compared body weight change between survivors relocated to temporary housing (TH) group versus other types of accommodation for up to 5 years after the Great East Japan Earthquake. METHODS: Longitudinal follow-up was conducted from 2011 to 2015 in a cohort of 9,909 residents of 42,831. We compared trends in body weight in the TH group (n = 3,169) and the non-TH group (n = 6,740) using a mixed linear regression model stratified by sex (mean age, 61.0 years old; male, 38.9%). RESULTS: In age-adjusted analysis, the body weight in the 2011 survey was not significantly different between two groups for either sex. In men, the TH group significantly increased body weight compared to the non-TH group since 2012. In women, body weight sharply increased in the TH group while body weight did not change in the non-TH group during survey time points. The interaction of living conditions and survey years was statistically significant in both sexes (men; F-value, 6.958; P < 0.001: women; F-value, 19.127; P < 0.001). CONCLUSION: Survivors relocated to temporary housing had an increased risk of weight gain. The weight gain in this group is a potential risk factor for metabolic syndrome in the post-disaster period.

Telomere shortening as a stress-related biomarker in children exposed to maternal chronic stress in utero measured 7 years after the Great East Japan Earthquake.

Seven years after the Great East Japan Earthquake, we investigated telomeres as a potential biomarker of maternal chronic stress in children according to the timing of exposure to the disaster. The subjects were children aged 5-9 years living in Rikuzentakata, Japan. Relative telomere length (rTL) was measured with PCR in saliva samples. The partial regression coefficient of the rTL was significantly shorter in the group of children conceived after the disaster than in the children who were in utero on the day of the disaster. Telomere length should be investigated as a biomarker for assessing disaster-related trauma in future studies.

Effect of temporary housing on incidence of diabetes mellitus in survivors of a tsunami-stricken area in 2011 Japan disaster: a serial cross-sectional RIAS study.

The association between incidence of diabetes mellitus (DM) and living conditions has not been studied after natural disasters. We compared the incidence of DM between individuals living in temporary housing (TH) and those living in other types of accommodation (non-TH) five years after the 2011 Great East Japan Earthquake. Longitudinal follow-up was conducted from 2011 to 2015 in a cohort of 7,491 residents of coastal communities in Iwate Prefecture directly impacted by the 2011 disaster (mean age, 61.6 years; men, 36.0%). We calculated the odds ratio of new onset of DM in the TH group (n = 2,372) compared with the non-TH group (n = 5,119) using discrete-time logit models stratified by sex and age classes (64 years or younger and older than 65 years). The TH group showed a significantly higher odds ratio (OR) for DM in men aged 64 years or younger (OR [95% confidence interval (CI)], 1.71 [1.03-2.85]; P-value = 0.040). In women, living conditions were not significantly associated DM. Survivors relocated to TH appeared to be at an increased risk of new onset DM.

Poor self-rated health predicts the incidence of functional disability in elderly community dwellers in Japan: a prospective cohort study.

BACKGROUND: Although previous large population studies showed elderly with poor self-rated health (SRH) to be at a high risk of functional disability in Western countries, there have been few studies in which the association between SRH and functional disability was investigated in Japanese community dwellers. The association between SRH and functional disability, defined as certification of the long-term care insurance (LTCI) system, in Japanese elderly community dwellers was examined in this study. METHODS: A total of 10,690 individuals (39.5% men, mean age of 71.4 years) who were 65 years of age or more who did not have a history of cardiovascular disease or LTCI certification were followed in this prospective study for 10.5 years. SRH was classified into four categories: good, rather good, neither good nor poor, and poor. A Cox proportional-hazards model was used to determine the hazard ratios (HRs) for the incidence of functional disability among the SRH groups for each sex. RESULTS: The number of individuals with functional disability was 3377. Men who rated poor for SRH scored significantly higher for functional disability (HR [95% confidence interval]: poor = 1.74 [1.42, 2.14]) while women who rated rather good, neither good nor poor, and poor scored significantly higher for functional disability (rather good =1.12 [1.00, 1.25], neither good nor poor = 1.29 [1.13, 1.48], poor = 1.92 [1.65, 2.24]: p for trend < 0.001 in both sexes). CONCLUSION: Self-rated health, therefore, might be a useful predictor of functional disability in elderly people.

Increased incidence of metabolic syndrome among older survivors relocated to temporary housing after the 2011 Great East Japan earthquake & tsunami.

BACKGROUND: Beyond the immediate toll of injuries and deaths, major disasters are often associated with long-term increased risks of chronic disease. We sought to investigate the incidence of metabolic syndrome (MetS) among survivors of the 2011 Great East Japan Earthquake and tsunami. METHODS: Subjects aged ≥18 years from the tsunami-stricken area participated in a prospective cohort study of disaster survivors (the RIAS Study) from 2011 to 2015. After excluding subjects who were previously diagnosed with MetS, we observed the cumulative incidence of MetS across four annual examinations among 7318 subjects (mean age, 59.8 years; 43.5% men). We defined MetS using the International Diabetes Foundation criteria. RESULTS: The 4-year cumulative incidence of MetS was 18.0% in the overall sample. The incidence was significantly higher among older women survivors relocated to prefabricated temporary housing (40.9%, 95% confidence interval, 36.4-44.6), and other types of housing (36.2%, 95% CI: 32.3-40.6) compared to those who were not relocated (34.1%, 95% CI: 30.9-37.4). An increase in incidence of MetS was not observed for older men, or younger survivors aged ≤64 years. CONCLUSION: Relocation to prefabricated temporary housing was a risk factor for increased incidence of MetS in older women.

Socioeconomic disparities in self-rated health in two East Asian countries: Comparative study between Japan and Korea.

Although Japan and South Korea share a number of commonalities, social security systems are very different. We opt to compare socioeconomic disparities in self-rated health between these two countries. The analytic sample included those aged 20 years and older from the nationally representative surveys in Japan (Comprehensive Survey of Living Conditions) and South Korea (Korean Community Health Survey). As socioeconomic status, we used income (quintiles of equivalized annual household income) and education (five categories). We measured socioeconomic inequalities using two indices; the Slope Index of Inequality (SII) and the Relative Index of Inequality (RII), in each age group for each country. In Japan, we found relatively little evidence of socioeconomic inequalities in self-rated health over the life course, on either the absolute or relative scale. In Korea, the absolute inequality assessed by SII of self-rated poor health was higher in middle and old age groups compared to other age groups, while relative inequality measured by RII was significantly higher in younger ages. In Japan with more generous welfare system to the older generations, health inequality was relatively lower compared to Korea. The gaps in health status for Korean people suggest where social policy might direct their efforts in the future - (a) reducing inequalities in working-age people by addressing the gap between standard workers & non-standard workers; and (b) improving the financial conditions of older people by shoring up the social security system.

Gender inequalities in poor self-rated health: Cross-national comparison of South Korea and Japan.

BACKGROUND: Japan and South Korea represent "outliers" among rich nations with regard to having achieved high life expectancy but also ranking near the bottom on United Nations indices of gender equality. In the present study, we compared gender inequalities in self-rated health (SRH) across the life course captured in nationally representative surveys from South Korea and Japan. Our comparative analysis focused on the following questions, (1) Do Japan and South Korea exhibit similar patterns of gender inequalities in health as found in western settings (e.g. the "gender paradox" whereby women enjoy longer life expectancy, but worseself-rated health compared to men)? (2) Can gender differences in educational attainment and income account for gender differences in health in Japan & Korea? (3) Do gender inequalities in self-rated health differ over the life-course in Japan compared to South Korea? METHODS: Cross-sectional data were drawn from nationally representative surveys in South Korea and Japan. We analyzed data for 239,076 participants aged 20 years or older (226,105 in South Korea and 12,971 in Japan). We evaluated the gender gap in poor SRH between two countries using logistic regression models controlling for covariates sequentially. RESULTS: (1) The absolute female/male gap in prevalence of poor SRH was much narrower in Japan compared to South Korea; (2) the prevalence ratios of poor SRH (women relative to men) were significantly higher in South Korea than in Japan after retirement age; (3) but the difference in the prevalence ratios of poor SRH by gender between two countries largely disappeared after adjusting for educational attainment & comorbidity. CONCLUSIONS: Each country needs to analyze their specific situations to understand what determines their population health status. In addition, there must exist other reasons for the"gender paradox" - i.e. why Japan & Korea have managed to achieve high longevity without gender equality.

The urine albumin-creatinine ratio is a predictor for incident long-term care in a general population.

BACKGROUND: Several types of cardiovascular diseases (CVDs) impair the physical and mental status. The purpose of this study was to assess the predictive ability of several cardiovascular biomarkers for identifying the incidence of disability as future recipients of public long-term care (LTC) service. METHODS: The subjects of this study were community-dwelling elderly individuals ≥ 65 years of age without a history of CVD (n = 5,755; mean age, 71 years). The endpoint of this study was official certification as a recipient of LTC. The cohort was divided into quartiles (Qs) based on the levels of three CVD biomarkers: the urinary albumin-creatinine ratio (UACR), plasma B-type natriuretic peptide concentration (BNP), and serum high-sensitivity C-reactive protein concentration (hsCRP). A time-dependent Cox proportional hazard model was used to determine the multi-adjusted relative hazard ratios (HRs) for incident LTC among the quartiles of each biomarker. RESULTS: During the follow-up (mean 5.6 years), 710 subjects were authorized as recipients of LTC. The HR was only significantly increased in the higher Qs of UACR (Q3, p < 0.01; Q4, p < 0.001). However, other biomarkers were not significantly associated with the endpoint. The risk predictive performance for the incidence of LTC as evaluated by an essential model (i.e. age- and sex-adjusted) was significantly improved by incorporating the UACR (net reclassification improvement = 0.084, p < 0.01; integrated discrimination improvement = 0.0018, p < 0.01). CONCLUSIONS: These results suggest that an increased UACR is useful for predicting physical and cognitive dysfunction in an elderly general population.

Ability of B-Type Natriuretic Peptide Testing to Predict Cardioembolic Stroke in the General Population　- Comparisons With C-Reactive Protein and Urinary Albumin.

BACKGROUND: The ability of cardiovascular biomarkers to predict the incidence of stroke subtypes remains ill-defined in the general population.Methods and Results:The blood levels of B-type natriuretic peptide (BNP) and high-sensitivity C-reactive protein (hs-CRP) and urinary albumin corrected by urinary creatinine (UACR) were determined in a general population (n=13,575). The ability to predict the incidence of ischemic stroke subtypes (lacunar, atherothrombotic, cardioembolic) for each biomarker was assessed based on the area under the receiver-operating characteristic curve (AUC-ROC) and using Cox proportional hazard modeling. The predictive abilities of UACR and hs-CRP for any subtype of ischemic event were found to be suboptimal. However, the ability of BNP to predict the incidence of cardioembolic stroke was excellent (AUC-ROC=0.81). When BNP was added to established stroke risk factors, the ability to predict cardioembolic stroke in terms of the AUC-ROC significantly improved (4-year follow-up, P=0.018; 8-year follow-up, P=0.009). Furthermore, when BNP was added to the JPHC score, the ability to predict cardioembolic stroke was significantly improved (net reclassification improvement=0.968, P<0.0001: integrated discrimination improvement=0.039, P<0.05). CONCLUSIONS: In the general population, plasma BNP was an excellent biomarker for predicting the incidence of cardioembolic stroke when used alone or in combination with established stroke risk factors.

Disease and injury trends among evacuees in a shelter located at the epicenter of the 2016 Kumamoto earthquakes, Japan.

Two huge earthquakes struck Kumamoto, Japan, in April 2016, forcing residents to evacuate. Few studies have reported early-phase disease and injury trends among evacuees following major inland earthquakes. We evaluated the trends among evacuees who visited a medical clinic in a shelter located at the epicenter of the 2016 Kumamoto earthquakes. The clinic opened on April 15, the day after the foreshock, and closed 3 weeks later. We reviewed medical charts related to 929 outpatient visits and conducted descriptive analyses. The evacuees experienced mild injuries and common diseases. The types of diseases changed weekly. Elderly people needed medical support for longer than other age groups. Future earthquakes may be inevitable, but establishing arrangements for medical needs or making precautions for infectious diseases in shelters could reduce the effects of earthquake-related health problems.