Educational inequalities in all-cause and cause-specific mortality in Japan: national census-linked mortality data for 2010-15.

BACKGROUND: Due to the lack of a national mortality inequality monitoring framework, the overall picture in Japan remains unclear. Here, we investigated educational inequalities in mortality and their cause-specific contribution in Japan. METHOD: Data were obtained by linking the 2010 Japanese population census and death records between 1 October 2010 and 30 September 2015. We included 7 984 451 Japanese people aged 30-79 years who had a unique 'matching key' generated by sex, birth year/month, address (municipality), marital status and age of spouse (9.9% of the total census population). We computed population-weighted all-cause and cause-specific age-standardized mortality rates (ASMRs) by education level. In addition, we calculated the slope index of inequality (SII), relative index inequality (RII) by education level, and population attributable fraction (PAF) referenced with the highest education (e.g. university graduation). RESULTS: Individuals with less education had higher all-cause and cause-specific ASMRs than highly educated individuals. All-cause SII (per 100 000 person-years) values were 433 (95% CI: 410-457) for men and 235 (95% CI: 217-252) for women. RII values were 1.48 (95% CI: 1.45-1.51) for men and 1.47 (95% CI: 1.43-1.51) for women. Estimated PAFs, excess premature deaths caused by educational inequalities, were 11.6% for men and 16.3% for women, respectively. Cerebrovascular diseases, ischaemic heart diseases and lung cancer were the major contributors to mortality inequalities for both sexes. CONCLUSIONS: This first census-based comprehensive report on cause-specific educational mortality inequalities suggested that differences in unfavourable health risk factors by educational background might be associated with these inequalities in Japan.

Association between spatial access and hospitalization for ambulatory care sensitive conditions: A retrospective cohort study using claims data.

Background: Hospitalization for ambulatory care sensitive conditions (ACSCs) is potentially preventable with timely and effective primary care but may increase owing to poor access. Spatial access inequalities exist between Japan and other countries. This retrospective cohort study examined the association between admission for ACSC and spatial accessibility to primary care. Methods: We used claims data and spatial data of 50-74 years-old beneficiaries of the National Health Insurance program in a large city in Japan from April 2013-March 2014 and followed them until March 2015. We used a multilevel Poisson regression model to assess the association between the number of ACSC admissions, the distance to the nearest clinic, and the number of physicians in a given area, adjusting for age, gender, comorbidities, number of visits, and household income. Results: Among 126,666 eligible beneficiaries (mean age 65.8 years, 54% were women), 1,793 (1.4%) were hospitalized for ACSCs. The ACSC admission rate was significantly higher in those with a distance to the nearest clinic of >1 km than in those with <0.3 km (incident rate ratio [IRR] 1.32, 95% confidence interval [CI] 1.03-1.69). In the stratified analyses, a longer distance to the nearest clinic was associated with higher ACSC admission rates among women (≥0.3 km and <0.5 km: IRR 1.48, 95% CI 1.01-2.17; ≥0.5 km and <1 km: IRR 1.74, 95% CI 1.19-2.56; >1 km: IRR 1.98, 95% CI 1.29-3.03, respectively) and those aged ≥65 years (≥0.3 km and <0.5 km: IRR 1.38, 95% CI 1.07-1.79; ≥0.5 km and <1 km: IRR 1.38, 95% CI 1.06-1.80; >1 km: IRR 1.48, 95% CI 1.10-1.98). Conclusion: Unfavorable spatial access was associated with ACSC admissions, particularly among women and older adults.

Different incidences of diabetic retinopathy requiring treatment since diagnosis according to the course of diabetes diagnosis: a retrospective cohort study.

We aimed to estimate the cumulative incidence of treatment-requiring diabetic retinopathy since clinical diagnosis of diabetes based on the course of diagnosis in a retrospective cohort study using Japan's medical claims and health checkup data (JMDC Claims Database; 2009-2020). We included patients whose diabetes was first diagnosed at medical facilities (hospitals/clinics). We grouped them by health checkup participation before diagnosis, health checkup results, and antidiabetic medication promptly after the diagnosis. The incidence of treatment-requiring diabetic retinopathy (laser photocoagulation, intraocular injection, or vitrectomy) was compared among the groups. Of 126,696 patients, those who started an antidiabetic medication promptly after diabetes diagnosis without a recent health checkup faced the highest risk of treatment-requiring diabetic retinopathy (1-/5-year cumulative incidence: 3.1%/6.0%). This increased risk was consistently observed across various analyses, including the Cox proportional hazard model, sensitivity analysis restricting to those with an eye examination, and sensitivity analysis using vitrectomy as the outcome. Among patients with HbA1c ≥ 6.5% at recent health checkups, those who promptly started an antidiabetic medication had a higher risk (1.4%/3.8%) than those who did not (0.7%/2.7%). Taking the information about the course of diabetes diagnosis is important to manage risk stratification for diabetic retinopathy appropriately.

Socioeconomic inequalities in self-rated health in Japan, 32 European countries and the United States: an international comparative study.

AIMS: Japan is known as a country with low self-rated health despite high life expectancy. We compared socioeconomic inequalities in self-rated health in Japan with those in 32 European countries and the US using nationally representative samples. METHODS: We analysed individual data from the Comprehensive Survey of Living Conditions (Japan), the European Union Statistics on Income and Living Conditions, and the Behavioral Risk Factor Surveillance System (US) in 2016. We used ordered logistic regression models with four ordinal categories of self-rated health as an outcome, and educational level or occupational class as independent variables, controlling for age. RESULTS: In Japan, about half the population perceived their health as 'fair', which was much higher than in Europe (≈20-40%). The odds ratios of lower self-rated health among less educated men compared with more educated were 1.72 (95% confidence interval (CI) 1.61-1.85) in Japan, and ranged from 1.67 to 4.74 in Europe (pooled; 2.10 (95% CI 2.01-2.20)), and 6.65 (95% CI 6.22-7.12) in the US. The odds ratios of lower self-rated health among less educated women were 1.79 (95% CI 1.65-1.95) in Japan, and ranged from 1.89 to 5.30 in Europe (pooled; 2.43 (95% CI 2.33-2.54)), and 8.82 (95% CI 8.29-9.38) in the US. Socioeconomic inequalities were large when self-rated health was low for European countries, but Japan and the US did not follow the pattern. CONCLUSIONS: Japan has similar socioeconomic gradient patterns to European countries for self-rated health, and our findings revealed smaller socioeconomic inequalities in self-rated health in Japan compared with those in western countries.

Estimation of Socioeconomic Inequalities in Mortality in Japan Using National Census-linked Longitudinal Mortality Data.

BACKGROUND: We aimed to develop census-linked longitudinal mortality data for Japan and assess their validity as a new resource for estimating socioeconomic inequalities in health. METHODS: Using deterministic linkage, we identified, from national censuses for 2000 and 2010 and national death records, persons and deceased persons who had unique personal identifiers (generated using sex, birth year/month, address, and marital status). For the period 2010-2015, 1,537,337 Japanese men and women aged 30-79 years (1.9% in national census) were extracted to represent the sample population. This population was weighted to adjust for confounding factors. We estimated age-standardized mortality rates (ASMRs) by education level and occupational class. The slope index of inequality (SII) and relative index inequality (RII) by educational level were calculated as inequality measures. RESULTS: The reweighted sample population's mortality rates were somewhat higher than those of the complete registry, especially in younger age-groups and for external causes. All-cause ASMRs (per 100,000 person-years) for individuals aged 40-79 years with high, middle, and low education levels were 1,078 (95% confidence interval [CI], 1,051-1,105), 1,299 (95% CI, 1,279-1,320), and 1,670 (95% CI, 1,634-1,707) for men, and 561 (95% CI, 536-587), 601 (95% CI, 589-613), and 777 (95% CI, 745-808) for women, respectively, during 2010-2015. SII and RII by educational level increased among both sexes between 2000-2005 and 2010-2015, which indicates that mortality inequalities increased. CONCLUSION: The developed census-linked longitudinal mortality data provide new estimates of socioeconomic inequalities in Japan that can be triangulated with estimates obtained with other methods.

Effects of cost sharing on long-term care service utilization among home-dwelling older adults in Japan.

OBJECTIVES: This study aimed to examine the effect of increased cost sharing on long-term care (LTC) service utilization among home-dwelling older adults, using nationwide long-term care insurance (LTCI) claims data in Japan. METHODS: In August 2015, the coinsurance rate for Japanese LTCI increased from 10% to 20% for higher-income beneficiaries. We analyzed 27,911,076 person-month observations between April 2015 and July 2016 from 1,983,163 home-dwelling older adults (aged ≥ 65 years). We employed a difference-in-differences approach to estimate the effect of the increased coinsurance rate on overall LTC service utilization and for each of the four main service subcategories. The control group comprised those whose coinsurance rates remained at 10%. RESULTS: The treatment group, whose coinsurance rate increased, accounted for 9.6% of all participants. The raised coinsurance rate caused statistically significant reductions of 0.46% (95% confidence interval [CI]: 0.36%, 0.56%) and $25.7 (95% CI: $23.7, $27.8) in the percentage of utilization of LTC services and total monthly LTC expenditures per person, respectively. Service utilization decreased in each of the four service subcategories. CONCLUSIONS: The increased coinsurance rate resulted in statistically significant but small reductions in LTC service utilization overall and in each service type among higher-income home-dwelling beneficiaries. Requiring more cost sharing from higher-income individuals may alleviate the fiscal burden on LTC systems without serious reductions in service utilization.

Prevalence and changes of low-value care at acute care hospitals: a multicentre observational study in Japan.

OBJECTIVES: We aimed to examine the use and factors associated with the provision of low-value care in Japan. DESIGN: A multicentre observational study. SETTING: Routinely collected claims data that include all inpatient and outpatient visits in 242 large acute care hospitals (accounting for approximately 11% of all acute hospitalisations in Japan). PARTICIPANTS: 345 564 patients (median age (IQR): 62 (40-75) years; 182 938 (52.9%) women) seeking care at least once in the hospitals in the fiscal year 2019. PRIMARY AND SECONDARY OUTCOME MEASURES: We identified 33 low-value services, as defined by clinical evidence, and developed two versions of claims-based measures of low-value services with different sensitivity and specificity (broader and narrower definitions). We examined the number of low-value services, the proportion of patients receiving these services and the proportion of total healthcare spending incurred by these services in 2019. We also evaluated the 2015-2019 trends in the number of low-value services. RESULTS: Services identified by broader low-value care definition occurred in 7.5% of patients and accounted for 0.5% of overall annual healthcare spending. Services identified by narrower low-value care definition occurred in 4.9% of patients and constituted 0.2% of overall annual healthcare spending. Overall, there was no clear trend in the prevalence of low-value services between 2015 and 2019. When focusing on each of the 17 services accounting for more than 99% of all low-value services identified (narrower definition), 6 showed decreasing trends from 2015 to 2019, while 4 showed increasing trends. Hospital size and patients' age, sex and comorbidities were associated with the probability of receiving low-value service. CONCLUSIONS: A substantial number of patients received low-value care in Japan. Several low-value services with high frequency, especially with increasing trends, require further investigation and policy interventions for better resource allocation.

Out-of-pocket payment and patients' treatment choice for assisted reproductive technology by household income: a conjoint analysis using an online social research panel in Japan.

BACKGROUND: Economic disparities affect access to assisted reproductive technology (ART) treatment in many countries. At the time of this survey, Japan provided partial reimbursement for ART treatment only for those in low- or middle-income classes due to limited governmental budgets. However, the optimal level of financial support by income class remains unclear. METHODS: We conducted a conjoint analysis of ART in Japan in January 2020. We recruited 824 women with fertility problems aged 25 to 44 years via an online social research panel. They completed a questionnaire of 16 hypothetical scenarios measuring six relevant ART attributes (i.e., out-of-pocket payment, pregnancy rate, risk of adverse effects, number of visits to outpatient clinics, consultation hours and kindness of staff) and their relations to treatment choice. RESULTS: Mixed-effect logistic regression models showed that all six attributes significantly influenced treatment preferences, with participants valuing out-of-pocket payment the most, followed by pregnancy rates and kindness of staff. Significant interactions occurred between high household income (≥ 8 million JPY) and high out-of-pocket payment (≥ 500,000 JPY). However, the average marginal probability of the highest-income patients (i.e., ≥ 10 million JPY, ineligible for the subsidy) receiving ART treatment at the average cost of 400,000 JPY was 47%, compared to 56 - 61% of other income participants, who opted to receive ART at an average cost of 100,000 JPY after a 300,000 JPY subsidy. CONCLUSION: Our results suggest that out-of-pocket payment is the primary determinant in patients' decision to opt for ART treatment. High-income patients were more likely to choose treatment, even at a high cost, but their income-based ineligibility for government financial support might discourage some from receiving treatment.

Hospitalizations for Ambulatory Care Sensitive Conditions in a Large City of Japan: a Descriptive Analysis Using Claims Data.

BACKGROUND: Hospitalization for ambulatory care sensitive conditions (ACSCs) is an indicator of the quality of primary care in different health systems. In Japan, where patients can choose any healthcare facility with universal health coverage (UHC), data on these admissions are unknown. OBJECTIVE: To describe the current situation of ACSC admissions in a city of Japan. DESIGN: Retrospective observational study using claims data. PARTICIPANTS: Beneficiaries aged 0-74 years of the National Health Insurance (NHI) program in a large city in the Greater Tokyo Area. We extracted ACSC admissions from all inpatient claims between April 2013 and March 2017. MAIN MEASURES: We calculated age- and sex-specific annual ACSC admission rates for three categories: acute, chronic, and vaccine-preventable. We estimated the age-adjusted admission rates by ACSC category according to administrative districts and rate ratios using Poisson regression models. We also estimated medical expenditures and lengths of stay for ACSC admissions. KEY RESULTS: Of 91,350 hospitalization episodes, we identified 7666 (8.4%) that were ACSC admissions. Males had higher annual ACSC admission rates than females (p < 0.001), especially for chronic ACSCs. Admission rates were lowest in those aged 15-39 years and higher in the youngest (0-4 years) and oldest (70-74 years) age groups. Age-adjusted chronic ACSC admission rates were lower in a newly developed area (rate ratio [RR]: 0.79, 95% confidence interval [CI]: 0.71-0.87) and higher in a residential area (RR: 1.14, 95% CI: 1.04-1.24) than in the center of the city. Total medical expenditures for all ACSC admissions accounted for 5.8% of the total inpatient expenditures of NHI in the city. CONCLUSIONS: ACSC admission rates in Japan were higher for males than for females and showed a U-shaped trend in terms of age, as in other countries with UHC, and deferred by region. This study provided possible factors to reduce ACSC admissions.

Incidence of interventions for diabetic retinopathy and serious lower-limb complications and its related factors in patients with type 2 diabetes using a real-world large claims database.

Aims: To examine the incidence of interventions for diabetic retinopathy and serious limb complications and to elucidate the patient attributes related to the incidence of each intervention based on real-world claims data from Japan. Materials and methods: A retrospective longitudinal study design involving a 9 year (2009-2018) claims database obtained from the JMDC Inc. Patients with type 2 diabetes aged 20-74 years taking antidiabetic medications were divided into two groups: "patients with newly initiated antidiabetic medication" (Group 1, n = 47,201) and "patients with continuing antidiabetic medication" (Group 2, n = 82,332). The incidence rate for each intervention was analyzed. We also divided Group 1 into the former and latter periods and investigated temporal changes. Results: The incidences of the first retinopathy intervention (laser photocoagulation, vitrectomy, or intraocular injection), vitrectomy, and lower-limb amputations in Group 1 were 7.46, 2.37, and 0.31 /1000 person-years, respectively. Those in Group 2 were about 1.2-1.5 times higher. Older age, insulin use, and being dependents rather than insured persons were associated with a higher incidence in both groups after adjustment. While the incidence of the interventions for retinopathy hardly changed during the observation period, that of lower-limb amputations decreased by 40%, with less statistical significance (p = 0.11). Conclusions: We showed the incidences of the first retinopathy interventions and lower-limb amputations and their secular trends in patients with diabetes, stratified by whether the antidiabetic medication was newly initiated or not. Older age, insulin use, and being dependents were risk factors of these interventions for diabetic complications. Supplementary Information: The online version contains supplementary material available at 10.1007/s13340-021-00566-7.

Occupational disparities in tumor grade and cytosolic HMGB1 expression in renal cell cancer.

OBJECTIVES: We sought to examine occupational disparities in tumor grade and cytosolic expression of high-mobility group box-1 (HMGB1) among renal cell cancer (RCC) patients. METHODS: This retrospective study included 318 RCC patients with complete information on occupation and pathology in Kanagawa Cancer Registry (KCR). Longest-held occupations were grouped into manual workers (e.g., manufacturing, construction) versus "others." Odds ratios (OR) and 95% confidence intervals (CI) for high-grade histology were estimated by logistic regression, adjusted for age and sex. We also examined a sub-sample of 74 low-grade RCC inpatients to estimate the OR for positive cytosolic HMGB1 expression in manual workers, adjusting for age, sex, and other available covariates. RESULTS: High-grade tumors were more prevalent in manual workers compared to other occupations: 23.0% (14/61) versus 10.9% (28/257, p = .01) with an adjusted OR of 2.28 (95% CI, 1.11-4.69). In the sub-sample of low-grade RCCs, positive cytosolic HMGB1 expression was more prevalent in manual workers compared to other occupations: 71.4% (10/14) versus 38.3% (23/60, p = .03) with a sex- and age-adjusted OR of 3.76 (95% CI, 1.03-13.7). CONCLUSIONS: Manual workers are associated with increased risks of high-grade renal cell tumors and cytosolic HMGB1 expression.

Occupational disparities in survival from common cancers in Japan: Analysis of Kanagawa cancer registry.

BACKGROUND: Little is known about occupational disparities in survival for common cancer sites in Japan. METHODS: Using data from a population-based cancer registry, we identified 32,870 cancer patients diagnosed during 1992-2011. We followed the patients for 5 years (median follow-up time 5.0 years). For each individual, we classified their longest-held occupation into 5 classes (upper non-manual, lower non-manual, manual, farmer, and others) following the Erikson-Goldthorpe-Portocarero scheme. Poisson regression models were used to estimate overall and site-specific mortality rate ratios (MRRs) and 95% confidence intervals (CI) for each occupational class, adjusted for sex, age, and diagnosis year. Upper non-manual workers served as the reference group. Additionally, using a binary categorization of occupations (manual workers versus non-manual workers), a causal mediation analysis with 4-way decomposition was performed to investigate the potential mediation of the association between occupation and overall mortality by cancer stage. RESULTS: Overall prognosis was good in this population (5-year overall survival was 81.7%). Compared with upper non-manual workers, both overall and cancer-specific mortality was higher in lower non-manual workers (MRR=1.14, 95% CI 1.05-1.24) and manual workers (MRR=1.40, 95% CI 1.29-1.53). After adjusting for the mediating influence of prognostic factors (stage and treatment), the observed occupational differences were attenuated but remained significant in manual workers: MRR = 1.23 (95% CI 1.08-1.39). Observed occupational disparities tended to be attributable to common cancers, i.e., stomach and lung among men and female breast cancer. Additionally, manual workers had 1.25 times higher odds for advanced stage. In the mediation analysis, the overall proportion explained by mediating effect of cancer stage was 29% (4% due to mediated interaction and 25% due to pure indirect effect). CONCLUSION: We documented occupational disparities in survival from commonly-occurring cancers in Japan. Occupational differences in cancer stage may explain one-third of the survival disparities.

Impact of social support for mothers as caregivers of cerebral palsy children in Japan.

PURPOSE: Social supports are critical to alleviate the psychological and physical burden of primary caregivers of children with disabilities. This study aims to (1) clarify how cerebral palsy in children affects caregiving burden of the mother, and (2) identify the social supports that can effectively reduce that burden. DESIGN AND METHODS: This is a cross-sectional study in which mothers of children with cerebral palsy completed questionnaires and provided data regarding their child's condition, family support, social support usage, degree of satisfaction with supports, and caregiving burden. RESULTS: We analyzed responses from 1190 mothers. Support usage, particularly of home-visit nursing, home care, home-visit rehabilitation, and mobility support, was higher in severely burdened groups. However, the proportion of satisfaction with social support in groups with light or no burden were higher, particularly in home care, home-visit rehabilitation, training/treatment, and short stays. Mothers whose children have an intellectual disability and gross exercise ≥1 in addition to tube feeding or intravenous nutrition especially felt a strong sense of burden. The most effective measure in reducing mother's sense of burden was short stays. CONCLUSIONS: Mothers with children who can move and have an intellectual disability felt more burden compared with mothers of bedridden children. The findings clarify that supports, such as home care and short stays, have a significant impact on reducing the mother's sense of burden. PRACTICE IMPLICATIONS: Due to the large sample size, we believe that the results can inform efforts to increase social support for caregivers.

Factors associated with the degree of glycemic deterioration among patients with type 2 diabetes who dropped out of diabetes care: A longitudinal analysis using medical claims and health checkup data in Japan.

AIMS/INTRODUCTION: To identify factors associated with worsening glycemic control after discontinuing diabetes care among patients with type 2 diabetes. MATERIALS AND METHODS: This retrospective cohort study combined medical claims and health checkup data between January 2005 and April 2018. Adult Japanese workers with type 2 diabetes who had dropped out from diabetes care for ≥4 months after receiving ≥18 months of non-intermittent care and had health checkup information both before and after the dropout were included. Factors associated with changes in HbA1c during the dropout period were identified using multiple linear regression analyses and depicting restricted cubic spline (RCS) curves. RESULTS: A total of 1,125 patients (mean age: 51.2 years, baseline HbA1c: 6.8%, and number of males: 93.7%) whose follow-up HbA1c increased to 7.6% after a mean 9.3-month dropout period were included. Deterioration in HbA1c was associated with higher baseline HbA1c and sulfonylurea or insulin use. The RCS curves illustrated that patients without antidiabetic medication had small changes in HbA1c (+0.5% from a baseline HbA1c of 7.0%), whereas those using sulfonylureas or insulin had an approximately 2% or more increase in HbA1c even when maintaining reasonable glycemic control before dropping out. CONCLUSIONS: Overall in this study, glycemic control worsened during treatment interruptions among patients who were mainly male employees. However, changes in HbA1c greatly varied based on baseline HbA1c and antidiabetic medication type. Caring for patients at risk of worsening glycemic control due to treatment dropout, especially those using sulfonylurea and insulin, is imperative.

Social capital and use of assisted reproductive technology in young couples: Ecological study using application information for government subsidies in Japan.

BACKGROUND: Assisted reproductive technology (ART) is a globally established treatment; however, large disparities exist in ART use among young couples. We investigated regional-level factors associated with ART use in Japan. METHODS: We calculated the use rate of ART using the number of women aged <35 years who applied for government subsidies in 2017; we divided that figure by the number of women aged 20-35 years in each prefecture. Prefectural-level average household income; social capital indicators including voting rate, volunteer rate, and move-in rate; and Gini coefficients as indicators of income inequality were linked to ART use, adjusting for prefectural size, the mean age of women at first marriage, number of ART facilities, and additional prefectural subsidies. RESULTS: The rate of ART use (per 10,000 women) varied significantly from 22.0 to 58.8 across Japan's 47 prefectures. Multivariate analysis demonstrated that the use rate increased by 0.048 (95% confidence interval [CI], 0.007 to 0.088) for each 10,000-yen increase in average household income and 1.5 (95% CI, 0.65 to 2.3) for each 1% increase in volunteer rate. Conversely, the use rate decreased by 18.4 (95% CI, -28.6 to -8.1) for each 1% increase in the move-in rate. There was no significant association between ART use and income inequality. CONCLUSION: Although we cannot infer causal relationships, the findings suggest that improving financial access and enhancing social capital may increase access to ART. Further research, particularly multilevel analysis using individual data, is required to confirm these findings.

Trends and socioeconomic inequalities in self-rated health in Japan, 1986-2016.

INTRODUCTION: Despite having very high life expectancy, Japan has relatively poor self-rated health, compared to other high-income countries. We studied trends and socioeconomic inequalities in self-rated health in Japan using nationally representative data. METHODS: The Comprehensive Survey of Living Conditions was analyzed, every 3 years (n ≈ 0.6-0.8 million/year) from 1986 to 2016. Whereas previous studies dichotomized self-rated health as an outcome, we used four categories: very good, good, fair, and bad/very bad. Proportional odds ordinal logistic regression models are used, with ordinal scale self-rated health as an outcome, and age category, survey year and occupational class or educational level as independent variables. RESULTS: In 2016, the age-adjusted percentages for self-rated health categorized as very good, good, fair, and bad/very bad, were 24.0, 17.1, 48.7, and 10.2% among working-age men, and 21.6, 17.5, 49.4, and 11.5% among working-age women, respectively. With 1986 as the reference year, the odds ratios (ORs) of less good self-rated health were lowest in 1995 (0.69; 95% Confidence Interval [95% CI]: 0.66-0.71 of working-age men), and highest in 2010 (1.23 [95% CI: 1.19-1.27]). The ORs of male, lower non-manual workers (compared to upper non-manual) increased from 1.12 (95% CI: 1.07-1.17) in 2010 to 1.20 (95% CI: 1.15-1.26) in 2016. Between 2010 and 2016, the ORs of working-age men with middle and low levels of education (compared to a high level of education) increased from 1.22 (95% CI: 1.18-1.27) to 1.34 (95% CI: 1.29-1.38), and from 1.47 (95% CI: 1.39-1.56) to 1.75 (95% CI: 1.63-1.88), respectively. The ORs of working-age women with middle and low levels of education also increased from 1.22 (95% CI: 1.17-1.28) to 1.32 (95% CI: 1.26-1.37), and from 1.74 (95% CI: 1.61-1.88) to 2.03 (95% CI: 1.87-2.21) during the same period. CONCLUSION: Japan has the unique feature that approximately 50% of the survey respondents rated their self-rated health as fair, but with important variations over time and between socioeconomic groups. In-depth studies of the role of socioeconomic conditions may shed light on the reasons for the high prevalence of poor self-rated health in Japan.

Adherence to Daily, Weekly, and Monthly Dosing Regimens of Bisphosphonates for Osteoporosis Treatment in Postmenopausal Women in Japan: A Retrospective Study Using Claims Data.

Poor medication adherence of osteoporosis patients is a major global medical problem because of its negative impact on health outcomes and quality of life. The aim of this study was to evaluate how differences in dosing regimens influence adherence to oral bisphosphonates using data from a large health insurance provider in Japan. This was a retrospective observational study using claims data obtained between October 2012 and January 2018, from the community-based National Health Insurance program of a large city in Japan. The data included in the analysis were obtained from women 60 to 74 years old whose oral bisphosphonate prescription was detected between April 2013 and February 2017. Treatment adherence was monitored from the initial prescription for one year, i.e., up to January 2018. Primary comparisons among the daily-dosing, weekly-dosing, and monthly-dosing groups were based on the mean medication possession ratio (MPR). Data from a total of 3,958 patients were analyzed. The numbers of patients aged 60-64, 65-69, and 70-74 were 425, 1,400, and 2,133, respectively. The highest mean MPR was 69.4% for the monthly-dosing of bisphosphonates, followed by the weekly-dosing at 63.5%, and daily-dosing at 57.2%. Using the Kruskal-Wallis test with Dunn-Bonferroni correction, there were significant differences in mean MPR for daily versus weekly (p < 0.01), daily versus monthly (p < 0.001), and weekly versus monthly dosing regimens (p < 0.05). These results suggest significantly more patients adhere to a monthly or weekly regimen of bisphosphonates in the treatment of osteoporosis than to a daily regimen.

Cumulative live birth rate according to the number of receiving governmental subsidies for assisted reproductive technology in Saitama Prefecture, Japan: A retrospective study using individual data for governmental subsidies.

PURPOSE: We investigated the cumulative live birth rate (CLBR) in women receiving governmental subsidies for assisted reproductive technology (ART) in Saitama Prefecture, Japan. METHODS: Women who applied for subsidies from Saitama Prefectural Government for the first time in 2016 were enrolled and followed up until the end of 2017. Treatment information, including live birth, was obtained from the Japanese ART registry by linking it with unique identification numbers for treatment. Patients' factors associated with having a live birth were investigated. RESULTS: Of 1,072 women (2,513 applications), 495 (46.2%) had a live birth with 8 (1.6%) twin pregnancies. The CLBR over six subsidized cycles was 53.7% for women aged <40 years, and 17.2% over three subsidized cycles for women 40-42 years; highest among women <35 years (58.4%), followed by those aged 35-39 years (49.3%). Multivariate analysis revealed patient age as the only independent factor for having a live birth. CONCLUSIONS: The CLBR of women receiving subsidies for ART was greatest in women aged <35 years. Effective policies for promoting ART among younger couples who seek infertility treatment are essential.

Claims-based algorithms for common chronic conditions were efficiently constructed using machine learning methods.

Identification of medical conditions using claims data is generally conducted with algorithms based on subject-matter knowledge. However, these claims-based algorithms (CBAs) are highly dependent on the knowledge level and not necessarily optimized for target conditions. We investigated whether machine learning methods can supplement researchers' knowledge of target conditions in building CBAs. Retrospective cohort study using a claims database combined with annual health check-up results of employees' health insurance programs for fiscal year 2016-17 in Japan (study population for hypertension, N = 631,289; diabetes, N = 152,368; dyslipidemia, N = 614,434). We constructed CBAs with logistic regression, k-nearest neighbor, support vector machine, penalized logistic regression, tree-based model, and neural network for identifying patients with three common chronic conditions: hypertension, diabetes, and dyslipidemia. We then compared their association measures using a completely hold-out test set (25% of the study population). Among the test cohorts of 157,822, 38,092, and 153,608 enrollees for hypertension, diabetes, and dyslipidemia, 25.4%, 8.4%, and 38.7% of them had a diagnosis of the corresponding condition. The areas under the receiver operating characteristic curve (AUCs) of the logistic regression with/without subject-matter knowledge about the target condition were .923/.921 for hypertension, .957/.938 for diabetes, and .739/.747 for dyslipidemia. The logistic lasso, logistic elastic-net, and tree-based methods yielded AUCs comparable to those of the logistic regression with subject-matter knowledge: .923-.931 for hypertension; .958-.966 for diabetes; .747-.773 for dyslipidemia. We found that machine learning methods can attain AUCs comparable to the conventional knowledge-based method in building CBAs.

Household income and medical help-seeking for fertility problems among a representative population in Japan.

BACKGROUND: Fertility treatments help many infertile couples to have children. However, disparities exist in access to fertility tests and treatments. We investigated the association between household income and medical help-seeking for fertility in Japan. METHODS: We conducted a cross-sectional study using nationally representative data from the National Fertility Survey 2015. Respondents were 6598 married women younger than 50 years old. The primary outcome was medical help-seeking for fertility among those who experienced fertility problems. Multiple logistic regression models were used to assess the association between household income and medical help-seeking, adjusting for age, length of marriage, educational level, employment status, number of children, childbearing desires, living with parents, and region of residence. RESULTS: Among 2253 (34%) women who experienced fertility problems, 1154 (51%) sought medical help. The proportion of help-seekers increased linearly from 43% in the low-income group (< 4 million Japanese yen [JPY]) to 59% in the high-income group (≥ 8 million JPY) (P for trend < 0.001). Respondents with upper-middle (6-8 million JPY) or high household income were more likely to seek medical help, compared to those with low household income: adjusted odds ratio [aOR] 1.37 (95% confidence interval [CI]: 1.00-1.86) and aOR 1.78 (95% CI: 1.29-2.47), respectively. CONCLUSIONS: We found that higher household income was associated with a higher probability of seeking medical help among Japanese women who experienced fertility problem. Along with policy discussion about additional financial support, further studies from societal, cultural, or psychological views are required.

Fertility treatments have helped millions of people to have a child. Although financial factors are known to play an important role in the decision to use fertility treatments, no previous studies have investigated how socioeconomic factors affect medical help-seeking for fertility in Japan. Therefore, we assessed the association between household income and medical help-seeking among couples with fertility problems in Japan, using nationally representative data from the National Fertility Survey 2015. Of the 6598 respondents (married women under 50 years old), one-third (2253) reported worrying about fertility problems, and half of those women (1154) sought medical help for fertility-related issues. The proportion of help-seekers was highest (59%) among those with high household income and lowest (43%) among those with low household income with a significant linear trend. Even after accounting for age, length of marriage, educational level, employment status, and other possibly related factors, those with higher household income were more likely to seek medical help for fertility tests and treatments. Japan provides various sources of financial support for fertility-related care, such as health insurance coverage for tests and early-stage treatments and partial subsidies for assisted reproductive technology treatments. However, the results indicate that further policy discussion about additional financial support and further studies focusing on barriers to care in Japan could help improve the situations for those with fertility problems.