Breastfeeding in Infancy in Relation to Subsequent Physical Size: A 20-year Follow-up of the Ibaraki Children's Cohort Study (IBACHIL).

BACKGROUND: Breastfeeding is said to prevent overweight and obesity in childhood but the evidence about its long-term impact on body size into adolescence and adulthood is scarce. We sought to examine the association between feeding types and subsequent physical size at the ages of 3, 6, 12, and 22 years. METHODS: The Ibaraki Children's Cohort (IBACHIL) Study, which began in 1992, involved a cohort of 4,592 Japanese children from 87 communities of a single prefecture whose parents answered health questionnaires about their child's health and life habits at the age of 3 years. Follow-up questionnaires were distributed to the same cohort when they were 6, 12, and 22 years old. Self-reported height and weight, body mass index (BMI), and overweight status at ages of 3 (n = 4,290), 6 (n = 1,999; proportion of participants analyzed = 47%), 12 (n = 2,227; 52%), and 22 (n = 1,459; 34%) years were compared according to feeding type (breastfeeding, formula feeding, and mixed feeding) during infancy. RESULTS: At the age of 3 years, multivariable adjusted-mean weight and prevalence of overweight were less for breastfed children than those formula-fed in both boys (weight: 14.6 kg vs 14.7 kg, P = 0.07, overweight: 6.3% vs 9.3%, P = 0.03) and in girls (14.0 kg vs 14.2 kg, P = 0.01 and 10.4% vs 13.6%, P = 0.06). However, there were no statistically significant differences in weight, BMI, and overweight at the ages of 6, 12, and 22 years according to feeding type. CONCLUSION: Breastfeeding may prevent overweight in childhood, but its impact is not significant in adolescence and adulthood.

Right bundle branch block and risk of cardiovascular mortality: the Ibaraki Prefectural Health Study.

Historically, a right bundle branch block has been considered a benign finding in asymptomatic individuals. However, this conclusion is based on a few old studies with small sample sizes. We examined the association between a complete right bundle branch block (CRBBB) and subsequent cardiovascular mortality in the general population in Japan. In this large community-based cohort study, data of 90,022 individuals (mean age, 58.5 ± 10.2 years; 66.2% women) who participated in annual community-based health check-ups were assessed. Subjects were followed up from 1993 to the end of 2016. Cox proportional hazards' models and log-rank tests were used for the data analysis. CRBBB was documented in 1,344 participants (1.5%). Among all included participants, CRBBB was associated with an increased risk of cardiovascular mortality after adjustment for all potential confounders (hazard ratio [HR] 1.21; 95% confidence interval [CI] 1.06-1.38). The increased risk of cardiovascular mortality was particularly evident in women aged < 65 years (HR 2.00; 95% CI 1.34-2.98) and men aged ≥ 65 years (HR 1.28; 95% CI 1.06-1.55). CRBBB is associated with an increased risk of cardiovascular mortality in women aged < 65 years and men aged ≥ 65 years. Clinicians should be aware of the presence of CRBBB in young women and elderly men, even if they exhibit no symptoms.

Does Cigarette Smoking Increase Traffic Accident Death During 20 Years Follow-up in Japan? The Ibaraki Prefectural Health Study.

BACKGROUND: Annually, more than 1.2 million deaths due to road traffic accidents occur worldwide. Although previous studies have examined the association between cigarette smoking and injury death, the mortality outcome often included non-traffic accident-related deaths. This study aimed to examine the association between cigarette smoking and traffic accident death. METHODS: We conducted a prospective cohort study using data from the Ibaraki Prefectural Health Study conducted from 1993 through 2013. The cohort included 97,078 adults (33,138 men and 63,940 women) living in Ibaraki Prefecture who were aged 40-79 years at an annual health checkup in 1993. We divided participants into four smoking status groups: non-smokers, ex-smokers, and current smokers who smoked <20 and ≥20 cigarettes per day. Hazard ratios (HRs) of traffic accident death were calculated using a Cox proportional hazards model. RESULTS: During 20 years of follow-up, the average person-years of follow-up were 16.8 and 18.2 in men and women, respectively. Among men, after adjusting for age and alcohol intake, HRs for traffic accident death among current smokers of <20 cigarettes/day and ≥20 cigarettes/day compared to non-smokers were 1.32 (95% confidence interval [CI], 0.79-2.20) and 1.54 (95% CI, 0.99-2.39), respectively. In contrast, among women, we found no association between smoking status and traffic accident deaths. CONCLUSION: In this prospective cohort study, we found a positive association, though marginally significant, between smoking and traffic accident death among men in Japan. Among women, because of the smaller number of deaths among smokers, adequate estimation could not be obtained.

High Hematocrit Levels Are Associated with Risk of Cardiovascular Mortality among Middle-Aged Japanese Women: The Ibaraki Prefectural Health Study (IPHS).

In Japan, heart disease and cerebrovascular disease were the second and fourth leading cause of death, respectively in 2014. Hematocrit, the ratio of the red blood cells to the total volume of blood is known to play a role in cardiovascular diseases. However, the relationship between elevated hematocrit and the risk of cardiovascular disease based on sex has not been examined in Asian countries. We analyzed data from the Ibaraki Prefectural Health Study, a community-based large cohort study, which included 87,533 individuals, aged 40 to 79 years living in 38 municipalities of the Ibaraki Prefecture, who had completed an annual health checkup in 1993, and were followed until 2013. The hematocrit levels of the subjects were categorized into 5 quintiles (Q1-Q5), and hazard ratios for cause-specific mortality were calculated using the Cox proportional hazards regression models. Age and other cardiovascular risk factors were the covariates in the study. During the follow-up for a mean of 17.9 years, 1,207 deaths (615 men and 592 women) due to acute myocardial infarction (AMI) were reported in this population. The p values for the trend in the Q3-Q5 groups were 0.661 for men and 0.020 for women. Additionally, these values were significant in younger (40 to 59 years) women but not in older (60 to 79 years) women. This study is the first one to demonstrate an association between high hematocrit level and risk of AMI mortality in younger Japanese women, but not in men and older women.

Validity of a Risk Prediction Equation for CKD After 10 Years of Follow-up in a Japanese Population: The Ibaraki Prefectural Health Study.

BACKGROUND: Chronic kidney disease (CKD) is an important health problem for which risk equations have been developed for Western populations. This study aimed to develop and validate a risk prediction equation for CKD in a Japanese population. STUDY DESIGN: Observational cohort study. SETTING & PARTICIPANTS: The study included 135,007 participants who completed an annual health checkup in 1993 to 1996 in the Ibaraki Prefecture in Japan. Participants were initially free of CKD (defined as stage 3, 4, or 5 CKD or proteinuria [2+ or 3+] by dipstick). Follow-up information was available from health checkups 10 years after the initial evaluation. We used data from 40,963 women and 17,892 men in the northern region of the prefecture for the development of risk prediction equations and 53,042 women and 23,110 men in the southern region for external validation. PREDICTORS: Age, estimated glomerular filtration rate (eGFR), body mass index, proteinuria, hematuria, hypertension, diabetes mellitus, smoking, and drinking. OUTCOME: Occurrence of CKD (defined as eGFR<60mL/min/1.73m2 and/or proteinuria [2+ or 3+] by dipstick). ANALYTICAL APPROACH: Logistic regression analysis to estimate risk for CKD stratified by sex. RESULTS: During follow-up, 7,500 cases of CKD developed in the northern region and 8,964, in the southern region. Older age, proteinuria (1+), higher systolic blood pressure, medication for hypertension, and current smoking were associated with increased risk for CKD in both sexes, whereas higher eGFR and daily alcohol intake were associated with lower risk. C statistics of risk estimation equations for CKD at 10 years were >0.8 for both the development and external validation populations, and discrimination of the risk estimation was fairly good in women and men. LIMITATIONS: Fluctuations in variables were not evaluated because the study used annual health checkups. This study excluded a large number of people for whom a 10-year health checkup was not available. CONCLUSIONS: Estimations of risk for CKD after 10 years of follow-up in a general Japanese population can be achieved with a high level of validity.

Impact of Speed-Eating Habit on Subsequent Body Mass Index and Blood Pressure Among Schoolchildren　- The Ibaraki Children's Cohort Study (IBACHIL).

BACKGROUND: Habitual speed eating is a risk factor of obesity but evidence of this in children is limited. We examined the association between speed-eating habit and subsequent body mass index (BMI) and blood pressure (BP) among Japanese children.Methods and Results:The community-based study comprised 1,490 Japanese boys and girls who were born in 1989, involved in the Ibaraki Children's Cohort Study at age 3 years, and had returned questionnaires at both ages 6 and 12 years. In a subsample, we measured BP (n=263). Speed-eating habit was categorized into 4 groups: Never, Quit, Newly, and Continuous. Sex-specific mean values of questionnaire-based BMI and measured BPs at age 12 were examined according to speed-eating habit. Children with continuous speed eating had a higher BMI at age 12 than those who had never had a speed-eating habit (20.0 vs. 17.9 kg/m2for boys (P<0.001); 20.0 vs. 18.4 kg/m2(P<0.001) for girls). Systolic BP at age 12 was higher in boys with continuous speed eating than in those without (117 vs. 110 mmHg, P=0.01), but such a difference was not observed in girls (112 vs. 111 mmHg, P=0.95). CONCLUSIONS: Habitualspeed eating was positively associated with subsequent BMI among boys and girls as well as with systolic BP among boys.

Impact and attribute of each obesity-related cardiovascular risk factor in combination with abdominal obesity on total health expenditures in adult Japanese National Health insurance beneficiaries: The Ibaraki Prefectural health study.

BACKGROUND: The aim of this study was to examine the attribution of each cardiovascular risk factor in combination with abdominal obesity (AO) on Japanese health expenditures. METHODS: The health insurance claims of 43,469 National Health Insurance beneficiaries aged 40-75 years in Ibaraki, Japan, from the second cohort of the Ibaraki Prefectural Health Study were followed-up from 2009 through 2013. Multivariable health expenditure ratios (HERs) of diabetes mellitus (DM), high low-density lipoprotein cholesterol (LDL-C), low high-density lipoprotein cholesterol (HDL-C), and hypertension with and without AO were calculated with reference to no risk factors using a Tweedie regression model. RESULTS: Without AO, HERs were 1.58 for DM, 1.06 for high LDL-C, 1.27 for low HDL-C, and 1.31 for hypertension (all P < 0.05). With AO, HERs were 1.15 for AO, 1.42 for DM, 1.03 for high LDL-C, 1.11 for low HDL-C, and 1.26 for hypertension (all P < 0.05, except high LDL-C). Without AO, population attributable fractions (PAFs) were 2.8% for DM, 0.8% for high LDL-C, 0.7% for low HDL-C, and 6.5% for hypertension. With AO, PAFs were 1.0% for AO, 2.3% for DM, 0.4% for low HDL-C, and 5.0% for hypertension. CONCLUSIONS: Of the obesity-related cardiovascular risk factors, hypertension, independent of AO, appears to impose the greatest burden on Japanese health expenditures.

Prognostic impact of supraventricular premature complexes in community-based health checkups: the Ibaraki Prefectural Health Study.

AIMS: The long-term prognosis of subjects with supraventricular premature complexes (SVPCs) remains unclear in the general population. The aim of this study was to examine the prognostic significance of SVPCs in community-based health checkups. METHODS AND RESULTS: We assessed 63 197 individuals (mean age, 58.8 ± 9.9 years; 67.6% women) who participated in annual community-based health checkups in 1993 and were followed until 2008. The primary endpoint was stroke death, cardiovascular death (CVD), or all-cause death during a 14-year mean follow-up, and the secondary endpoint was first atrial fibrillation (AF) event in subjects without self-reported heart diseases or AF at baseline. Compared with subjects without SVPCs, the multivariate-adjusted hazard ratios (HRs) [95% confidence interval (CI)] of stroke death, CVD, and all-cause death in subjects with SVPCs were 1.24 (0.98-1.56) for men and 1.63 (1.30-2.05) for women, 1.22 (1.04-1.44) for men and 1.48 (1.25-1.74) for women, and 1.08 (0.99-1.18) for men and 1.21 (1.09-1.34) for women, respectively. Atrial fibrillation occurred in 386 subjects during the follow-up (1.05/1000 person-years). The presence of SVPCs at baseline was the significant predictor of AF onset [HRs (95% CI): 4.87 (3.61-6.57) for men and 3.87 (2.69-5.57) for women]. Propensity score matched analyses also revealed the presence of SVPCs was significantly associated with increased risks of AF incidence and CVD even after adjusting the potential confounders. CONCLUSION: The presence of SVPCs in 12-lead electrocardiograms was a strong predictor of AF development, and associated with increased risk of CVD in general population.

Impact of Caregiver Type for 3-Year-Old Children on Subsequent Between-Meal Eating Habits and Being Overweight From Childhood to Adulthood: A 20-Year Follow-up of the Ibaraki Children's Cohort (IBACHIL) Study.

BACKGROUND: Because of the increasing number of mothers who continue to work after childbirth, participation in childcare has diversified. However, the impact of the main caregiver on children's habits has not been determined. We sought to examine the effect of caregiver differences on childhood habituation of between-meal eating and body mass index (BMI). METHODS: The Ibaraki Children's Cohort Study involved 4592 Japanese children whose parents answered health questionnaires at age 3. Follow-up questionnaires were distributed to parents when children were 6 and 12 years old and to study subjects directly when they were 22 years old. We compared prevalence of between-meal eating and overweight as well as mean BMI at ages 6, 12, and 22 years, by their main daytime caregiver at age 3. RESULTS: Compared to children cared for by mothers, those cared for by grandparents had a higher prevalence of between-meal eating before dinner for boys and girls at ages 6 and 12 years. At age 22 years, boys cared for by grandparents had a higher prevalence of overweight than those cared for by mothers (18.5% versus 11.2%, P = 0.037), but no such difference was noted in girls. However, both boys and girls cared for by grandparents had higher mean BMI over time than those cared for by mothers (coefficient = 0.47 kg/m(2) for boys and coefficient = 0.35 kg/m(2) for girls). CONCLUSIONS: Being cared for by grandparents at age 3 was associated with subsequent between-meal eating habits, being overweight, and increased mean BMI from childhood to adulthood.

The dose-response relationship between body mass index and the risk of incident stage ≥3 chronic kidney disease in a general japanese population: the Ibaraki prefectural health study (IPHS).

PURPOSE: To examine the relationship between body mass index (BMI) and the risk of stage ≥3 chronic kidney disease (CKD) in a general Japanese population. METHODS: A total of 105 611 participants aged 40-79 years who completed health checkups in Ibaraki Prefecture, Japan, and were free of CKD in 1993 were followed-up through 2006. Stage ≥3 CKD was defined by an estimated glomerular filtration rate <60 mL/min/1.73 m(2) reported during at least 2 successive annual surveys or as treatment for kidney disease. Hazard ratios (HRs) for the development of stage ≥3 CKD relative to the BMI categories were calculated using the Cox proportional hazards regression model, which was adjusted for possible confounders and mediators. RESULTS: During a mean follow-up of 5 years, 19 384 participants (18.4%) developed stage ≥3 CKD. Compared to a BMI of 21.0-22.9 kg/m(2), elevated multivariable-adjusted HRs were observed among men with a BMI ≥23.0 kg/m(2) and women with a BMI ≥27.0 kg/m(2). Significant dose-response relationships between BMI and the incidence of stage ≥3 CKD were observed in both sexes (P for trend <0.001). CONCLUSIONS: Obesity was associated with the risk of developing stage ≥3 CKD among men and women.

Defect passivation in methylammonium/bromine free inverted perovskite solar cells using charge-modulated molecular bonding.

Molecular passivation is a prominent approach for improving the performance and operation stability of halide perovskite solar cells (HPSCs). Herein, we reveal discernible effects of diammonium molecules with either an aryl or alkyl core onto Methylammonium-free perovskites. Piperazine dihydriodide (PZDI), characterized by an alkyl core-electron cloud-rich-NH terminal, proves effective in mitigating surface and bulk defects and modifying surface chemistry or interfacial energy band, ultimately leading to improved carrier extraction. Benefiting from superior PZDI passivation, the device achieves an impressive efficiency of 23.17% (area ~1 cm2) (low open circuit voltage deficit ~0.327 V) along with superior operational stability. We achieve a certified efficiency of ~21.47% (area ~1.024 cm2) for inverted HPSC. PZDI strengthens adhesion to the perovskite via -NH2I and Mulliken charge distribution. Device analysis corroborates that stronger bonding interaction attenuates the defect densities and suppresses ion migration. This work underscores the crucial role of bifunctional molecules with stronger surface adsorption in defect mitigation, setting the stage for the design of charge-regulated molecular passivation to enhance the performance and stability of HPSC.

Relationship between cold temperature and cardiovascular mortality, with assessment of effect modification by individual characteristics: Ibaraki Prefectural Health Study.

BACKGROUND: Cold temperature has been reported to contribute to cardiovascular mortality, but it is not clear which people are more susceptible to cold temperature. METHODS AND RESULTS: The relationship between ambient temperature and mortality was examined in 3,593 subjects from the Ibaraki Prefectural Health Study who died of cardiovascular disease during a mean follow-up period of 9.7±4.0 years. Daily values of meteorological variables were obtained from the Japan Meteorological Agency. Time-stratified case cross-over analysis was used. The multivariate odds ratios (ORs; 95% confidence interval) per 1°C decrease in daily maximum temperature over the day of death and the 2 days prior to this day adjusted for relative humidity were 1.018 (1.003-1.034) for all cardiovascular deaths and 1.025 (1.003-1.048) for stroke deaths. Risk-stratified analysis showed that younger subjects aged <80 years and those with hyperglycemia were more susceptible to cold temperature. The OR of all cardiovascular deaths related to cold temperature was 1.034 (1.012-1.056) for subjects aged <80 years, and that of stroke deaths was 1.076 (1.023-1.131) for those with hyperglycemia. CONCLUSIONS: Exposure to cold temperature triggers cardiovascular deaths. Additionally, younger age and hyperglycemia could enhance susceptibility to cold temperature.

Low serum LDL cholesterol levels are associated with elevated mortality from liver cancer in Japan: the Ibaraki Prefectural health study.

Liver cancer a global public health concern and well known for poor prognosis. The association between low total cholesterol level and liver cancer has been reported. However, the association between low low-density lipoprotein (LDL) cholesterol levels and liver cancer is still unclear. The aim of this study was to examine the relationship between LDL cholesterol level and liver cancer mortality. A total of 16,217 persons (5,551 men and 10,666 women) aged 40-79 years in 1993 were followed until 2008. LDL cholesterol levels were divided into four categories (<80 mg/dl, 80-99 mg/dl, 100-119 mg/dl, and ≥120 mg/dl). Hazard ratio of LDL cholesterol level for liver cancer mortality was calculated using a multivariable Cox proportional hazards model. Covariates were age, sex, alanine transaminase, body mass index, alcohol intake and smoking status, all of which were correlated with LDL cholesterol levels. There were 51 deaths (32 men and 19 women) from liver cancer. Multivariable hazard ratios of liver cancer deaths for LDL cholesterol levels of <80 mg/dl was 4.33 (95% confident interval [CI]: 1.94, 9.68), for LDL cholesterol levels of 80-99 mg/dl was 1.03 (95% CI: 0.42, 2.53), and for LDL cholesterol levels of ≥120 mg/dl was 0.43 (95% CI: 0.20, 0.92) compared with LDL cholesterol levels of 100-199 mg/dl (p for trend<0.01). Therefore, low LDL cholesterol levels are associated with elevated risk of liver cancer mortality. Low LDL cholesterol may be a predictive marker for death due to liver cancer.

Risk Factors for Mortality From Aortic Aneurysm and Dissection: Results From a 26-Year Follow-Up of a Community-Based Population.

Background Aortic aneurysm rupture and acute aortic dissection are life-threatening conditions and represent an ever-growing public health challenge. Comprehensive epidemiologic investigations for their risk factors are scant. We aimed to investigate risk factors associated with mortality from aortic diseases through analysis of a community-based Japanese cohort. Methods and Results IPHS (Ibaraki Prefectural Health Study) comprises 95 723 participants who took part in municipal health checkups in 1993. Factors considered for analysis included age, sex, body mass index, blood pressure, serum lipids (high-density lipoprotein [HDL] cholesterol, non-HDL cholesterol, and triglycerides), diabetes, antihypertensive and lipid-lowering drug use, and smoking and drinking habits. Cox proportional hazards models were applied to evaluate the associations between these variables and mortality from aortic diseases. During the median 26-year follow-up, 190 participants died of aortic aneurysm rupture, and 188 died of aortic dissection. An increased multivariable hazard ratio (HR) for mortality from total aortic diseases was observed for high systolic blood pressure (1.61 [1.00-2.59]), diastolic blood pressure (2.95 [1.95-4.48]), high non-HDL cholesterol (1.63 [1.19-2.24]), low HDL cholesterol (1.86 [1.29-2.68]), and heavy (>20 cigarettes/day) smoking habit (2.46 [1.66-3.63]). A lower multivariable HR was observed for diabetes (0.50 [0.28-0.89]). Conclusions Smoking habit, higher systolic blood pressure and diastolic blood pressure levels, higher non-HDL, and lower HDL cholesterol levels were positively associated with mortality from total aortic diseases, whereas diabetes was inversely associated.

Mild retinopathy is a risk factor for cardiovascular mortality in Japanese with and without hypertension: the Ibaraki Prefectural Health Study.

BACKGROUND: It is unclear whether mild hypertensive retinopathy is a risk factor for mortality. This study examined whether mild hypertensive retinopathy could be a risk factor for cardiovascular mortality in subjects with and without hypertension. METHODS AND RESULTS: In this cohort study, 87 890 individuals (29 917 men and 57 973 women) 40 to 79 years of age in 1993 were followed up until 2008. Retinal photography was classified as normal, grade 1, or grade 2 based on the Keith-Wagener-Barker system. Risk ratios for all-cause and cause-specific mortality for each classification were calculated with Cox proportional hazards regression models. Covariates included age, systolic blood pressure, antihypertensive medication use, and other cardiovascular risk factors. Multivariable hazard ratios for total cardiovascular disease mortality were 1.24 (95% confidence interval [CI], 1.12-1.38) and 1.23 (95% CI, 1.03-1.47) for grades 1 and 2 among men and 1.12 (95% CI, 1.01-1.24) and 1.44 (95% CI, 1.24-1.68) for grades 1 and 2 among women, respectively. Hazard ratios for total stroke mortality were 1.31 (95% CI, 1.13-1.53) and 1.38 (95% CI, 1.08-1.77) for grades 1 and 2 among men and 1.30 (95% CI, 1.12-1.50) and 1.70 (95% CI, 1.36-2.11) for grades 1 and 2 among women, respectively. For both hypertensive and normotensive subjects of each sex, multivariable hazard ratios for all-cause mortality, total cardiovascular mortality, and total stroke mortality were significantly higher for grade 1 or 2 compared with normal. CONCLUSIONS: Mild hypertensive retinopathy is a risk factor for cardiovascular mortality independently of cardiovascular risk factors among men and women with and without hypertension.

Diabetes Mellitus Modifies the Association of Serum Triglycerides with Ischemic Cardiovascular Disease Mortality: The Ibaraki Prefectural Health Study (IPHS).

AIM: Diabetes mellitus and hypertriglyceridemia may adversely interact with the development of ischemic cardiovascular disease, but epidemiological evidence on this issue is scarce. We hypothesized that the impact of hypertriglyceridemia on ischemic cardiovascular disease (ischemic heart disease and ischemic stroke) would differ according to the presence or absence of diabetes mellitus and tested our a priori hypothesis under a large population-based prospective study. METHODS: A total of 90,468 men and women aged 40-79 years in 1993 were enrolled in the Ibaraki Prefectural Health Study (IPHS), a community-based cohort study of Japanese. The participants' serum triglyceride levels (mostly nonfasting) were measured every 5 years, and the participants were followed up for mortality from ischemic cardiovascular disease through 2016. Hazard ratios (95% confidence intervals) were calculated according to 5-year updated triglyceride levels (＜100, 100-149, 150-199, 200-299, and ≥ 300 mg/dl). RESULTS: During 1,795,877 person-years, there were 3,323 deaths from ischemic cardiovascular diseases (1,968 ischemic heart diseases and 1,355 ischemic strokes). We found no association between triglyceride levels and the risk of mortality from ischemic cardiovascular disease after adjustment for known cardiovascular risk factors. However, when stratified by the presence or absence of diabetes mellitus, excess mortality from ischemic cardiovascular disease appeared among participants with diabetes mellitus with triglyceride levels of ≥ 300 mg/dl. Further adjustment for high-density lipoprotein-cholesterol attenuated the association toward being statistically nonsignificant. CONCLUSION: The impact of high serum triglyceride levels on the risk of ischemic cardiovascular disease mortality was confined to participants with diabetes mellitus.

Atrial Fibrillation With and Without Cardiovascular Risk Factors and Stroke Mortality.

AIM: The association between atrial fibrillation (AF) and risk of stroke mortality among men and women without traditional cerebrocardiovascular risk factors (TCVRFs) is unclear. This study aimed to determine whether AF was a risk factor for stroke and total cardiovascular disease mortality among individuals without TCVRFs. METHODS: A total of 90,629 Japanese subjects from the Ibaraki Prefectural Health Study aged 40-79 years, with and without TCVRFs, were studied from 1993 to 2013. Hazard ratios (HRs) were calculated using the Cox proportional hazard regression model stratified by sex and the presence of TCVRFs. Covariates were age, systolic blood pressure, anti-hypertensive medication use, and serum total cholesterol levels. A standard 12-lead electrocardiogram at rest was used to screen AF. Cause-specific mortality was classified according to the International Classification of Disease code. RESULTS: Compared with participants without AF, multivariable-adjusted hazard ratios (with 95% confidence intervals) for stroke mortality among participants without TCVRFs were 4.3 (1.1-17.8) and 15.0 (5.5-40.8) for men and women with AF, respectively. HRs for total cardiovascular disease mortality were 6.2 (2.8-14.2) for men and 10.7 (4.8-24.1) for women. For participants with TCVRFs, multivariable-adjusted HRs for stroke mortality were 3.1 (2.2-4.6) and 4.3 (2.6-7.3), whereas HRs for total cardiovascular disease mortality were 2.9 (2.2-3.8) and 3.5 (2.4-5.1) for men and women, respectively. CONCLUSIONS: AF was found to be an independent risk factor for stroke and total cardiovascular mortality even in individuals without other TCVRFs.

Long-Term Exposure to Particulate Matter and Mortality from Cardiovascular Diseases in Japan: The Ibaraki Prefectural Health Study (IPHS).

AIM: To examine the association between long-term exposure to suspended particulate matter (SPM) and cardiovascular mortality in Japan after controlling for known major confounding factors among a large middle and elderly cohort study in Ibaraki Prefecture, Japan. METHODS: We followed 91,808 residents (men 34%) who undertook a national health check-up at age 40-79 years for 17 years (1993-2010). Two different exposure indices were adopted: baseline SPM concentration (in the year 1990) and average SPM concentration for the first (average of 1990 and 1995) and the second half (average of 2005 to 2009) of the study period. Sex-specific adjusted risk ratios (RRs) for cardiovascular mortality were calculated using general mixed Poisson regression models after adjusting the age, BMI, history of diabetes mellitus and hypertension, creatinine, glutamic pyruvic transaminase, total cholesterol, high-density lipoprotein cholesterol, smoking, alcohol, and temperature. The variation between seven medical administration areas was also taken into account as a random effect. RESULTS: Baseline SPM concentration was associated with an increased risk of mortality from all cardiovascular diseases, coronary artery disease, and stroke. The adjusted RRs (95% confidence interval [CI]) per 10 µg/m3 increase in SPM concentration for all cardiovascular mortality were 1.147 (1.014-1.300) for men and 1.097 (0.985-1.222) for women. The point estimate of RR was highest for non-hemorrhagic stroke in men (1.248 [0.991-1.571]), although CI overlapped the unity. The RRs seemed slightly lower in the second half than in the first half, though the CIs widened in the second half. CONCLUSION: Our results suggest that long-term exposure to SPM is associated with an increased risk of all cardiovascular mortality for men in Ibaraki, Japan.

Associations between metabolic syndrome and mortality from cardiovascular disease in Japanese general population, findings on overweight and non-overweight individuals. Ibaraki Prefectural Health Study.

BACKGROUND: The impact of being overweight, as a component of the metabolic syndrome (MetS), for cardiovascular disease (CVD) mortality was investigated and compared with the predictive value of MetS by 2 different definitions. METHODS AND RESULTS: A 12-year prospective study of 30,774 Japanese men and 60,383 women aged 40-79 years was conducted. The multivariate hazard ratio (HR; 95% confidence interval) of total CVD mortality for overweight subjects with >or=2 additional risk factors with reference to subjects with 0 of 4 MetS components was 1.83 (1.41-2.38) for men and 1.90 (1.45-2.49) for women, and for non-overweight subjects with >or=2 additional risk factors 1.75 (1.38-2.24) and 1.97 (1.52-2.55), respectively. The proportion of excess CVD deaths in the latter group was 1.5-fold higher than that in the former group. Multivariate HRs of coronary heart disease and total CVD mortality for MetS by the modified criteria of the American Heart Association/National Heart, Lung, and Blood Institute were 1.62 (1.31-2.00) and 1.23 (1.09-1.39), respectively, for men and 1.32 (1.05-1.65) and 1.12 (1.00-1.25), respectively, for women. The respective HRs for MetS by the International Diabetic Federation definition did not reach statistical significance, except for coronary heart disease in men. CONCLUSIONS: Non-overweight individuals with metabolic risk factors, as well as overweight individuals with such factors, should be targeted to reduce the CVD burden in the general population.

[Two-dimensional classification of prefectures by life expectancy and weighted disability prevalence (WDP) with a comparison of regional characteristics].

OBJECTIVES: The objectives of the present study were to classify 47 prefectures into clusters using mortality and disability data concerning elderly people in Japan, and to identify regional characteristics of each group using community healthcare welfare indicators. METHODS: Weighted disability prevalence (WDP) was computed using determined utilities and prevalence of long-term care insurance. Prefectures were classified by hierarchical cluster analysis of life expectancy at age 65 years and age-adjusted WDP at the ages of 65-89 years, and discrimination of community healthcare welfare among clusters was examined using ANOVA and the Games-Howell pairwise comparison test. The characteristics of each group were then compared by means of differences among identified clusters. RESULTS: Four clusters were identified: a long life expectancy low disability group, a long life expectancy high disability group, a short life expectancy low disability group, and a short life expectancy high disability group. For men, health expenditures for the elderly, long-term care insurance benefits and the number of doctors were significantly higher in the long life expectancy high disability group than in the short life expectancy low disability group (in order of indicators: P<0.01, P<0.05, P<0.01). Age-adjusted mortality rates from heart disease and stroke in men were significantly lower in the long life expectancy high disability group than in the short life expectancy low disability group (in order of indicators: P<0.01, P<0.001). For women, health expenditures for the elderly and long-term care insurance benefits were significantly higher in the long life high disability group than in the short life expectancy low disability group (both indicators: P<0.05). Cancer and heart disease mortality in women were significantly lower in the long life expectancy low disability group than in the short life expectancy high disability group (in order of indicators: P<0.05, P<0.01). CONCLUSION: Classification of prefectures in groups with similar regional characteristics, comparison among regions, and identification of group characteristics are useful for objective assessment of the present state of the regions, establishing policy goals, and objectively evaluating policy effectiveness.