Relationship Between Hemoglobin Concentration and Cardiovascular Disease Mortality in a 25-Year Follow-up Study of a Japanese General Population - NIPPON DATA90

BACKGROUND

Deviations of hemoglobin from normal levels may be a factor in cardiovascular disease (CVD) risk; however, conclusive evidence is lacking. In addition, preclinical conditions may influence hemoglobin concentrations, but studies focusing on reverse causation are limited. Thus, we examined the relationship between hemoglobin concentrations and CVD mortality risk, considering reverse causation.Methods and Results: In a prospective cohort representative of the general Japanese population (1990-2015), we studied 7,217 individuals (mean age 52.3 years; 4,219 women) without clinical CVD at baseline. Participants were categorized into sex-specific hemoglobin quintiles (Q1-Q5) and data were analyzed using the Cox proportional hazards model adjusted for possible confounders. During a 25-year follow-up, 272 men and 334 women died from CVD. Adjusted hazard ratios for CVD mortality across sex-specific quintiles, using Q3 as the reference, were significantly higher for Q1 (1.40; 95% confidence interval [CI] 1.08-1.82) and Q5 (1.49; 95% CI 1.14-1.96), and remained significant after excluding deaths within the first 5 years of follow-up to consider reverse causation (1.35 [95% CI 1.02-1.79] and 1.45 [95% CI 1.09-1.94], respectively). A similar U-shaped association was seen between transferrin saturation levels and CVD mortality, but after excluding deaths within the first 5 years the association was significant only for Q1.

CONCLUSIONS

Low and high hemoglobin concentrations were associated with an increased risk of CVD mortality.

High blood pressure and colorectal cancer mortality in a 29-year follow-up of the Japanese general population: NIPPON DATA80

Onco-hypertension has been proposed, although associations of high blood pressure (BP) with cancer risk remain inconsistent. We examined associations of high BP with risk of mortality from stomach, lung, colorectal, liver, and pancreatic cancers independent of possible confounders in an analysis that excluded deaths within the first 5 years of follow-up to consider the reverse causality. In a prospective cohort representative of the general Japanese population (1980-2009), we studied 8088 participants (mean age, 48.2 years; 56.0% women) without clinical cardiovascular disease or antihypertensive medication at baseline. Fine-Gray competing risks regression was used to estimate hazard ratios for 10 mmHg higher BP adjusted for confounders including smoking, alcohol-drinking, obesity, and diabetes mellitus. During 29-year follow-up, 159 (2.0%), 159 (2.0%), 89 (1.1%), 86 (1.1%), and 68 (0.8%) participants died from stomach, lung, colorectal, liver, and pancreatic cancers, respectively. We observed a positive association of high BP with risk of colorectal cancer mortality but not with mortality risks from any other cancers. The association with colorectal cancer mortality for systolic and diastolic BP was evident in those aged 30-49 years (hazard ratios 1.43 [95% confidence interval, 1.22-1.67] and 1.86 [1.32-2.62], respectively) but not in those aged 50-59 years and ≥60 years (P for age interaction <0.01 for systolic and diastolic BP). The associations with colorectal cancer mortality were similar in the analyses stratified by smoking, alcohol-drinking, obesity, and diabetic status. In conclusion, high BP among young to middle-aged adults was independently associated with risk of colorectal cancer mortality later in life.

Association between Dietary Patterns and Serum Low Density Lipoprotein Cholesterol in Japanese Women and Men: The Japan Multi-Institutional Collaborative Cohort (J-MICC) Study

AIMS

The association between dietary patterns and serum low density lipoprotein (LDL) cholesterol would be changing in recent dietary habits in Japan. We investigated the relationship between dietary patterns and serum LDL cholesterol in a large general population.

METHODS

From the baseline survey of Japan Multi-Institutional Collaborative Cohort Study between 2005 and 2013, 27,237 participants (13,994 were women) aged 35-69 years were cross-sectionally analyzed. Using a semi-quantitative food frequency questionnaire, five major sex-specific dietary patterns were identified using factor analysis. We assessed serum LDL cholesterol by quintiles of dietary pattern factor score.

RESULTS

We identified dietary patterns; "vegetable rich pattern" , "meat and fried food rich pattern" and "high bread and low rice pattern" in women and men; "fish and shellfish rich pattern" and "high confectioneries and low alcohol pattern" in men; "healthy Japanese diet pattern" and "high alcohol and low rice pattern" in women. Serum LDL cholesterol in men was associated with "high bread and low rice pattern" score (Q5 was 4.2 mg/dL higher than Q1, p for trend ＜0.001) and "high confectioneries and low alcohol pattern" scores (Q5 was 9.5 mg/dL higher than Q1, p for trend ＜0.001). In women, serum LDL cholesterol was associated with "high bread and low rice pattern" score (Q5 was 7.1 mg/dL higher than Q1, p for trend ＜0.001).

CONCLUSION

Some recent dietary patterns in Japan were associated with serum LDL cholesterol. Serum LDL cholesterol was associated with high bread and low rice pattern in both sex, and high confectioneries and low alcohol pattern in men.

Incidence and In-Hospital Mortality of Acute Myocardial Infarction: A Report from a Population-Based Registry in Japan

AIM

To investigate the incidence and in-hospital mortality of acute myocardial infarction (AMI) by conforming to the Universal Definition of Myocardial Infarction (UDMI) in a population-based registry.

METHODS

The Shiga Stroke and Heart Attack Registry is a multicenter, population-based registry in the Shiga Prefecture, designed to evaluate the incidence and prognosis of acute cerebro-cardiovascular diseases. We registered patients with AMI as defined by the UDMI, who developed AMI from January 2014 to December 2015 in the Shiga Prefecture. The incidence rate of AMI was calculated and standardized for age by a direct method using the 2015 Japanese population. We also evaluated the in-hospital mortality among hospitalized patients with ST-elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI).

RESULTS

A total of 1,587 patients were diagnosed with AMI, and the age-adjusted incidence rate was 61.9 per 100,000 person-years. The proportions of patients with STEMI, NSTEMI, and type 3 myocardial infarction were 57%, 30%, and 12%, respectively. The incidence rates of AMI increased with age regardless of sex, which was the highest in those 85 years and older, with 389.7 per 100,000 person-years in men and 221.8 per 100,000 person-years in women. Age-adjusted in-hospital mortality among hospitalized patients with STEMI and NSTEMI was 12.3% and 5.8%, respectively.

CONCLUSIONS

This population-based registry clarified the age-adjusted incidence rate of AMI under the application of the UDMI, highlighting that in-hospital mortality is still high among patients with STEMI in Japan.

Epidemiology of Acute Aortic Dissection in a General Population of 1.4 Million People in Japan - Shiga Stroke and Heart Attack Registry

BACKGROUND

Acute aortic dissection (AAD) is a life-threatening cardiovascular disease, with a reported incidence rate ranging from 2.5 to 7.2 per 100,000 person-years in several population-based registries in Western countries, but epidemiological data are lacking in Japan.Methods and Results: The Shiga Stroke and Heart Attack Registry is an ongoing multicenter population-based registry of cerebro-cardiovascular diseases. We enrolled patients who developed AAD, defined by any imaging examination method from 2014 to 2015 in Shiga Prefecture. Death certificates were used to identify cases that were not registered at acute care hospitals. The incidence rates of AAD were calculated by age categories and adjusted using standard populations for comparison. We evaluated differences in patient characteristics between Stanford type A-AAD and type B-AAD subtypes. A total of 402 incident cases with AAD were analyzed. The age-adjusted incidence rates using the 2015 Japanese population and the 2013 European Standard Population were 15.8 and 12.2 per 100,000 person-years, respectively. Compared with cases of type B-AAD, those with type A-AAD were older (75.0 vs. 69.9 years, P=0.001) and more likely to be women (62.3% vs. 28.6%, P<0.001).

CONCLUSIONS

Population-based incidence rates of AAD in Japan appear to be higher than in previous reports from Western countries. Incident cases with type A-AAD were older and female predominance.

Comparison of the loci associated with HbA1c and blood glucose levels identified by a genome-wide association study in the Japanese population

Aims

Hemoglobin A1c (HbA1c) levels are widely employed to diagnose diabetes. However, estimates of the heritability of HbA1c and glucose levels are different. Therefore, we explored HbA1c- and blood glucose-associated loci in a non-diabetic Japanese population.

Methods

We conducted a two-stage genome-wide association study (GWAS) on variants associated with HbA1c and blood glucose levels in a Japanese population. In the initial stage, data of 4911 participants of the Japan Multi-Institutional Collaborative Cohort (J-MICC) were subjected to discovery analysis. In the second stage, two datasets from the Tohoku Medical Megabank project, with 8175 and 40,519 participants, were used for the replication study. Association of the imputed variants with HbA1c and blood glucose levels was determined via linear regression analyses adjusted for age, sex, body mass index (BMI), smoking, and genetic principal components (PC1-PC10). Moreover, we performed a BMI-stratified GWAS on HbA1c levels in the J-MICC. The discovery analysis and BMI-stratified GWAS results were validated with re-analyses of normalized HbA1c levels adjusted for site in addition to the above, and blood glucose adjusted for fasting time as an additional covariate.

Results

Genetic variants associated with HbA1c levels were identified in KCNQ1 and TMC6. None of the genetic variants associated with blood glucose levels in the discovery analysis were replicated. Association of rs2299620 in KCNQ1 with HbA1c levels showed heterogeneity between individuals with BMI ≥ 25 kg/m2 and BMI < 25 kg/m2.

Conclusions

The variant rs2299620 in KCNQ1 might affect HbA1c levels differentially based on BMI grouping in the Japanese population.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13340-023-00618-0.

Relationship of Higher-level Functional Capacity With Long-term Mortality in Japanese Older People: NIPPON DATA90

BACKGROUND

Basic and instrumental activities of daily living (BADL and IADL, respectively) are known predictors of mortality. However, the relationship between higher-level functional capacity (HLFC) and mortality and related sex differences have rarely been investigated.

METHODS

A prospective population-based cohort study was conducted in 1,824 older residents (≥65 years) with independent BADL from 300 randomly selected areas in Japan from 1995, and the participants were followed up until 2010. Using the Cox proportional hazards model, the relationship between HLFC and mortality risk was investigated, with adjustment for possible confounders. HLFC was assessed using the Tokyo Metropolitan Institute of Gerontology Index of Competence. Baseline data were collected using a questionnaire or by home-visit interviews.

RESULTS

During an average 12.2-year follow-up, all-cause death was observed in 836 (45.8%) participants. Impaired HLFC was significantly associated with mortality (hazard ratio [HR] 1.37; 95% confidence interval [CI], 1.13-1.65). Lower social role was significantly associated with higher mortality risk in men (HR 1.38; 95% CI, 1.13-1.68). Lower IADL and intellectual activity were significantly associated with higher mortality risk in women (HR 1.50; 95% CI, 1.15-1.95 and HR 1.46; 95% CI, 1.19-1.79, respectively). The relationship between HLFC and mortality risk showed a similar tendency among cardiovascular diseases, stroke, cancer, and pneumonia.

CONCLUSION

Impaired HLFC was associated with a high risk of all-cause mortality among community-dwelling older people with independent BADL. In particular, social role in men and IADL and intellectual activity in women were associated with long-term mortality risk.

Association between C-Reactive Protein Levels and Functional Disability in the General Older-Population: The Takashima Study

AIMS

High-sensitivity C-reactive protein (hsCRP) associates with atherosclerotic diseases such as stroke. However, previous results on the association between hsCRP levels and functional disability were controversial.

METHODS

We analyzed 2,610 men and women who did not exhibit functional disability or death within the first 3 years of the baseline survey and those aged 65 years or older at the end of follow-up. The levels of hsCRP were assessed using latex agglutination assay at baseline survey from 2006 to 2014. Functional disability was followed up using the long-term care insurance (LTCI) program until November 1, 2019. Functional disability was defined as a new LTCI program certification. Cox proportional hazards model with competing risk analysis for death was used to evaluate the association between hsCRP levels and future functional disability.

RESULTS

During a 9-year follow-up period, we observed 328 cases of functional disability and 67 deaths without prior functional disability incidence. The multivariable-adjusted hazard ratio (HR, 95% confidence interval [CI]) of functional disability in log-transferred hsCRP levels was 1.43 (1.22-1.67) in men and 0.97 (0.81-1.15) in women. When hsCRP level was analyzed as a categorical variable, low hsCRP levels (＜1.0 mg/l) as the reference, the multivariable-adjusted HR (95% CI) of functional disability in high hsCRP levels (≥ 3.0 mg/l) was 2.37 (1.56-3.62). Similar results were observed when stratified by sex, but it was not significant in women.

CONCLUSIONS

This study demonstrates that low-grade systemic inflammation to assess hsCRP might predict the future incidence of functional disability, especially in men.

Control of Diabetes Mellitus and Long-Term Prognosis in Stroke Patients: The Shiga Stroke and Heart Attack Registry

BACKGROUND

The relationship between diabetes control status and long-term prognosis after stroke incidence remains unclear. This study aimed to investigate the effect of diabetes status at admission on long-term survival in patients with first-ever stroke.

METHODS

A retrospective cohort study was conducted based on the Shiga Stroke and Heart Attack Registry in Japan. Patients were classified according to their diabetes status and glycated hemoglobin (HbA1c) value at hospital admission into the following: (1) free of diabetes (no history of diabetes and HbA1c <6.5%); (2) good control (history of diabetes and HbA1c <7%; free of history and 6.5% ≤HbA1c <7%); and (3) poor control (with or without a history of diabetes and HbA1c ≥7%). Multivariable Cox regression models were used to evaluate the association between diabetes status and long-term survival from stroke onset. Additionally, we also evaluated the association between diabetes status and conditional survival, beginning 29 days after stroke onset.

RESULTS

A total of 6,331 first-ever stroke patients were eligible for this study. Among study patients, the mean (±SD) age was 72.85 ± 13.19 years, and the mean (±SD) follow-up year was 2.76 ± 1.66 years; additionally, 42.09% of patients were women. Among patients with all strokes, considering the free-of-diabetes group as the reference group, the adjusted hazard ratio (95% confidence interval) for mortality was 1.26 (1.10, 1.44) in the good control group and 1.22 (1.05, 1.41) in the poor control group. Among patients with ischemic stroke, the adjusted hazard ratio was 1.24 (1.06, 1.46) in good control group and 1.27 (1.08, 1.50) in poor control group. After excluding patients who died within 28 days, the adjusted hazard ratio for conditional mortality in the poor control group was 1.31 (1.12, 1.54) among all stroke patients and 1.29 (1.08, 1.54) among ischemic stroke patients. No significant associations were observed between diabetic status and long-term mortality in intracerebral hemorrhage patients.

CONCLUSIONS

The findings suggest that first-ever stroke patients with diabetes exhibited a higher risk of all-cause mortality than those without diabetes, particularly in the overall stroke and ischemic stroke populations. Additionally, in stroke populations after 28 days of onset, high risk of long-term mortality was stated in stroke patients with poor HbA1c control.

Characteristics of shifting ability in children with mild intellectual disabilities: an experimental study with a task-switching paradigm

BACKGROUND

Shifting enables flexible switch between tasks or mental sets. It is a component of the executive function that plays critical roles in human behaviour control. However, shifting ability in individuals with intellectual disability (ID) has not been well clarified because of the use of intellectually demanding tasks in previous studies. The present study invented a novel shifting task with minimal intellectual demands and aimed to clarify the characteristics of shifting in adolescents with ID.

METHODS

Adolescents with ID (n = 21) and chronological-age-matched (n = 10) and mental-age-matched controls (n = 33) performed a novel shifting task with simple rule switching (i.e. change in direction). Analyses focused on the switch cost or the increase in the reaction time associated with rule switching.

RESULTS

Two subtypes of adolescents with ID were found with respect to the switch cost: one that lacks it and another with an increased switch cost. The lack of a switch cost was unique to the subgroup adolescents with ID and was not indicated in the control group.

CONCLUSIONS

The present study indicated that shifting in adolescents with ID does not depend solely on their intellectual function and is highly heterogeneous. This finding further implies that executive functions, including shifting, must be evaluated separately from their intellectual functions.

Genetic polymorphism of pleiotrophin is associated with pain experience in Japanese adults: Case-control study

Genetic factors play a role in individual differences in pain experience. Here, we performed a genome-wide association study (GWAS) to identify novel loci regulating pain processing. We conducted a 2-stage GWAS and the candidate single-nucleotide polymorphisms (SNPs) association study on pain experience using an exploratory cohort of patients with cancer pain. The confirmatory cohort comprised of participants from the general population with and without habitual use of analgesic medication. In the exploratory cohort, we evaluated pain intensity using a numerical rating scale, recorded daily opioid dosages, and calculated pain reduction rate. In the confirmatory cohort, pain experience was defined as habitual nonsteroidal anti-inflammatory drug usage. Using linear regression models, we identified candidate SNP in the exploratory samples, and tested the association between phenotype and experienced pain in the confirmatory samples. We found 1 novel SNP (rs11764598)-located on the gene encoding for pleiotrophin on chromosome 7-that passed the genome-wide suggestive significance at 20% false discovery rate (FDR) correction in the exploratory samples of patients with cancer pain (P = 1.31 × 10-7, FDR = 0.101). We confirmed its significant association with daily analgesic usage in the confirmatory cohort (P = .028), although the minor allele affected pain experience in an opposite manner. We identified a novel genetic variant associated with pain experience. Further studies are required to validate the role of pleiotrophin in pain processing.

Associations of Genome-Wide Polygenic Risk Score and Risk Factors With Hypertension in a Japanese Population

Background:

Although many polygenic risk scores (PRS) for cardiovascular traits have been developed in European populations, it is an urgent task to construct a PRS and to evaluate its ability in non-European populations. We developed a genome-wide PRS for blood pressure in a Japanese population and examined the associations between this PRS and hypertension prevalence.

Methods:

We performed a cross-sectional study in 11 252 Japanese individuals who participated in the J-MICC (Japan Multi-Institutional Collaborative Cohort) study. Using publicly available GWAS summary statistics from Biobank Japan, we developed the PRS in the target data (n=7876). With >30 000 single nucleotide polymorphisms, we evaluated PRS performance in the test data (n=3376). Hypertension was defined as systolic blood pressure of 130 mm Hg or more, or diastolic blood pressure of 85 mm Hg or more, or taking an antihypertensive drug.

Results:

Compared with the middle PRS quintile, the prevalence of hypertension at the top PRS quintile was higher independently from traditional risk factors (odds ratio, 1.73 [95% CI, 1.32–2.27]). The difference of mean systolic blood pressure and diastolic blood pressure between the middle and the top PRS quintile was 4.55 (95% CI, 2.26–6.85) and 2.32 (95% CI, 0.86–3.78) mm Hg, respectively. Subgroups reflecting combinations of Japanese PRS and modifiable lifestyles and factors (smoking, alcohol intake, sedentary time, and obesity) were associated with the prevalence of hypertension. A European-derived PRS was not associated with hypertension in our participants.

Conclusions:

A PRS for blood pressure was significantly associated with hypertension and BP traits in a general Japanese population. Our findings also highlighted the importance of a combination of PRS and risk factors for identifying high-risk subgroups.

Relationship of leisure-time and household physical activity level and type with cardiovascular disease: secondary analysis of the Takashima Study data

Background

High levels of participation in leisure-time and household physical activity lower the risk of cardiovascular disease (CVD), although it is unclear whether the number of activity types is related to new-onset CVD. We aimed to evaluate the effect of the amount of leisure-time physical activity and the number of types of leisure-time physical activities on the risk of CVD incidence.

Methods

From 2002 to 2003, 3,741 participants without any history of CVD participated in the Takashima Study. Data on the amount of leisure-time and household physical activity and the types of leisure-time and household physical activity were obtained from a self-administered questionnaire. Hazard ratios for CVD (acute myocardial infarction and stroke) incidence (follow-up data from 2002 to 2013), according to the participation level and number of activity types, were calculated using Cox proportional hazards models.

Results

The mean age of the subjects was 58.7 ± 13.1 years. During the mean follow-up period of 8.0 ± 1.1 years, 92 participants developed CVD. An inverse dose–response relationship was noted between the amount of leisure-time and household physical activity and CVD events. After adjusting for baseline characteristics, lifestyle-related diseases, and the amount of physical activity other than leisure-time and household, the risk of CVD onset was compared by dividing the participants into two groups by the level of participation; the highest activity group had an adjusted hazard ratio (95% confidence interval) of 0.40 (0.20–0.82) compared to the lowest activity group. Compared to participants who engaged in 0–1 type of activity, participants who engaged in two or more types of activities had a multivariable-adjusted hazard ratio (95% confidence interval) of 0.31 (0.12–0.79).

Conclusion

Increasing the amount of leisure-time and household physical activity and promoting engagement in two or more types of such activities may reduce the rate of CVD incidence in the Japanese general population.

Predictors of lower limb fractures in general Japanese: NIPPON DATA90

Objective

This study aimed to investigate the incidence rates and predictors of lower limb fractures in a general Japanese population.

Methods

NIPPON DATA is a nationwide, long-term, prospective cohort study of individuals who participated in the National Cardiovascular Survey Japan and the National Nutrition Survey in 1990. Overall, 3,134 individuals (1,827 women, 1,307 men) who participated in follow-up assessments in 1995, 2000, and/or 2006 were included in the present analysis. The outcomes of this study were lower limb fractures (including proximal femur fractures).

Results

The mean age at baseline was 63.8 years in women and 63.1 years in men. The average body mass index (BMI) was 23.3 kg/m² in women and 22.9 kg/m² in men. During a mean follow-up of 12.1 years, 271 total lower limb fractures were observed. In women, older age, lower BMI, and less intake of vegetables were associated with increased risks of proximal femur fractures. With regard to the outcome of total lower limb fractures, less intake of vegetables and regular exercise were significant predictors in women. Calcium intake was not significantly associated with proximal femur or total lower limb fractures. There were no significant predictors of proximal femur or total lower limb fractures in men, except for age.

Conclusions

Aging was a significant risk factor for proximal femur and total lower limb fractures in both men and women. With regard to modifiable risk factors, low BMI and low intake of vegetables were associated with increased risks of proximal femur and/or total lower limb fractures in the general population of Japanese women.

The 21-Year Trend of Stroke Incidence in a General Japanese Population: Results from the Takashima Stroke Registry, 1990-2010

INTRODUCTION

Since the 1960s, the stroke morality rate in Japan has declined significantly. Although several risk factors for stroke have become more evident due to increasingly Westernized lifestyle, there have been no population-based registry data on recent time trends in stroke incidence in Japan. The purpose of this study is to determine these trends in stroke incidence using a population-based registry.

METHODS

Data were obtained from the Takashima Stroke Registry, which covers approximately 50,000 residents in Takashima City, Japan. The age- and sex-standardized stroke incidence rate was estimated using the direct method. Average annual relative changes of stroke incidence were estimated using Poisson regression models.

RESULTS

We identified a total of 2,371 patients with first-ever stroke during the period 1990-2010. Crude incidence rates of total stroke (per 100,000 person-years) were 225 in the early period (1990-2001) and 187 in the late period (2002-2010), and the mean age at onset of stroke increased from 71.9 years in the early period to 74.8 years in the late period. Age- and sex-standardized incidence rates of stroke (per 100,000 person-years) decreased from 327 in the early part of this study period and 206 in the later period. During the 21-year period, age- and sex-standardized average annual relative reduction in stroke incidence was statistically significant (-3.7% per year). When stratified into early and late periods, the adjusted annual relative reduction in stroke incidence was observed during the early period (-2.1% per year), and there were no significant changes during the late period.

CONCLUSIONS

In this population-based registry, there was a significant reduction in incidence of stroke from 1990 to 2010. Although the speed of reduction in stroke incidence appears to have slowed down after 2000, continuous public health measures are required to provide further protection against stroke.

A genome-wide association study on meat consumption in a Japanese population: the Japan Multi-Institutional Collaborative Cohort study

Recent genome-wide association studies (GWAS) on the dietary habits of the Japanese population have shown that an effect rs671 allele was inversely associated with fish consumption, whereas it was directly associated with coffee consumption. Although meat is a major source of protein and fat in the diet, whether genetic factors that influence meat-eating habits in healthy populations are unknown. This study aimed to conduct a GWAS to find genetic variations that affect meat consumption in a Japanese population. We analysed GWAS data using 14 076 participants from the Japan Multi-Institutional Collaborative Cohort (J-MICC) study. We used a semi-quantitative food frequency questionnaire to estimate food intake that was validated previously. Association of the imputed variants with total meat consumption per 1000 kcal energy was performed by linear regression analysis with adjustments for age, sex, and principal component analysis components 1-10. We found that no genetic variant, including rs671, was associated with meat consumption. The previously reported single nucleotide polymorphisms that were associated with meat consumption in samples of European ancestry could not be replicated in our J-MICC data. In conclusion, significant genetic factors that affect meat consumption were not observed in a Japanese population.

Association between Stress-Coping Strategy and Functional Disability in the General Older Adult Population: The Takashima Study

BACKGROUND

Both physical and psychological factors have been associated with functional disability. However, the associations between stress-coping strategies and future functional disability remain unclear.

METHODS

We analyzed 2,924 participants who did not have incidence of functional disability or death within the first 3 years of the baseline survey and were aged 65 years or more at the end of follow-up. Stress-coping strategies were assessed via a self-administered questionnaire (emotional expression, emotional support seeking, positive thought, problem-solving, and disengagement) in a baseline survey from 2006 to 2014. Levels of coping strategies were classified as low, middle, and high based of frequency. Functional disability decline was followed up using the long-term-care insurance program until November 1, 2019. Functional disability decline was defined as a new long-term-care insurance program certification. Cox proportional hazards model with competing risk analysis for death was used to evaluate associations between coping strategy levels and functional disability.

RESULTS

During the follow-up period, we observed 341 cases of functional disability and 73 deaths without previous incidence of functional disability. A significant inverse association between "positive thought" and "problem-solving" and future functional disability was observed. Multivariable adjusted hazard ratios (95% confidence interval) for functional disability were 0.68 (0.51-0.92) for high levels of "positive thought" and 0.73 (0.55-0.95) for high levels of "problem-solving," compared with low levels of the coping strategies. The inverse association was stronger in men.

CONCLUSIONS

Some subcomponents of stress-coping strategies might be associated with future incidence of functional disability among older adults.

74Relationship of higher-level functional capacity on long-term mortality in Japanese population: NIPPON DATA90

Background

Little is known about the relationships between higher-level functional capacity (HLFC) and mortality, and its gender difference.

Methods

NIPPON DATA90 is the cohort study of the National Cardiovascular Survey of Japan in 1990. We followed up 1824 Japanese adults over 65 years who were independent in basic activities of daily living in 1995 until 2010. HLFC was measured in 1995 using the total score and 3 subscales (instrumental activities of daily living [IADL], intellectual activity, social role) by the Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC). The association of HLFC to mortality was evaluated by adjusted hazard ratio (HR) and 95% confidence interval (CI) using the Cox proportional hazard model.

Results

During average 12.2-year follow-up, 836 participants (45.8%) died. Participants with impaired total TMIG-IC score showed significantly higher risk of mortality (adjusted HR 1.37; 95%CI 1.14-1.66) compared with normal participants, even after adjusting for other variables. The corresponding HR was significant only in women (HR 1.42; 95% CI 1.10-1.83). Among the 3 subscales, only impaired social role showed significantly higher risk of mortality (HR 1.37; 95%CI 1.12-1.67) in men. In contrast, IADL and intellectual activity showed significantly higher risk in women (HR 1.51; 95%CI 1.16-1.96) (HR 1.46; 95%CI 1.19-1.80).

Conclusions

Impaired HLFC was related to higher risk of long-term mortality in Japanese elderly at baseline. Especially among women, IADL and intellectual activity were important predictors, whereas social role was important in men.

Key messages

Impaired HLFC was related to long-term mortality in Japanese elderly.

Seasonal Variation in Incidence of Stroke in a General Population of 1.4 Million Japanese: The Shiga Stroke Registry

INTRODUCTION

The purpose of this study was to investigate seasonal variation in stroke incidence using data from a large-scale stroke registry of general population in current Japan.

METHODS

Shiga Stroke Registry (SSR) is an ongoing population-based registry of stroke that occurred in the Shiga Prefecture in central Honshu, Japan. A total 6,688 cases of first-ever stroke, with onset dates ranging from 1 January 2011 to 31 December in 2013 were included in this study. Incidence rates of first-ever stroke in each season were estimated using the person-year approach and adjusted for age and sex using the Poisson regression models.

RESULTS

From 2011 to 2013, we identified a total of 6,688 stroke cases (3,570 men, 3,118 women), of which 4,480 cases had ischemic stroke (2,518 men, 1,962 women), 1,588 had intracerebral hemorrhage (857 men, 731 women) and 563 had subarachnoid hemorrhage (166 men, 397 women). Age- and sex-adjusted incidence rates of total stroke were 151 (95% confidence interval [CI] 144-160, p = <0.001 vs. summer) in spring, 130 (95% CI 122-137) in summer, 141 (95% CI 133-149, p = 0.020 vs. summer) in autumn and 170 (95% CI 161-179, p = <0.001 vs. summer) in winter. Seasonal variation was more pronounced in intracerebral hemorrhage than in ischemic stroke.

CONCLUSION

In the present large-scale stroke registry of general population, incidence rates of stroke were highest in winter and lowest in summer in current Japan.

Relationship of Ambient Temperature Parameters to Stroke Incidence in a Japanese Population - Takashima Stroke Registry, Japan, 1988-2010

BACKGROUND

Using a population-based stroke registry system, we evaluated the relationship between ambient temperature parameters and stroke incidence in a Japanese population.Methods and Results:We analyzed data from the Takashima Stroke Registry, which records all stroke occurrences in Takashima City, Japan. The study period of 8,401 days was divided into quintiles of daily weather parameters, and the middle quintile was used as the reference category. Incidence rates (IR per 100,000 person-years) were calculated across the quintiles. Poisson regression analysis was used to calculate the effect of temperature parameters on stroke incidence. There were 2,405 first-ever strokes (1,294 men), including 1,625 ischemic, 545 cerebral hemorrhages, 213 subarachnoid hemorrhages, and 22 unclassified strokes. The stroke IR was higher in the middle quintile of average temperature, 357.3 (328.4-388.8), and for other parameters. After adjustment for age and sex, for all stroke, the incidence rate ratio (IRR) in the highest (Q5: IRR 0.81, 95% confidence interval (CI) 0.71-0.92) and the second-highest (Q4: IRR 0.80, 95% CI 0.71-0.91) quintile was lower than that in the middle quintile (Q3: Reference). Analogous results were observed for the minimum, maximum, and lag-days temperatures, also in the subtypes and across ≥65 years of age, also in females.

CONCLUSIONS

Higher temperatures, irrespective of the parameter (average, minimum, or maximum), had a protective effect against stroke occurrence in Japan.

Differential Effect of Polymorphisms on Body Mass Index Across the Life Course of Japanese: The Japan Multi-Institutional Collaborative Cohort Study

BACKGROUND

Obesity is a reported risk factor for various health problems. Genome-wide association studies (GWASs) have identified numerous independent loci associated with body mass index (BMI). However, most of these have been focused on Europeans, and little evidence is available on the genetic effects across the life course of other ethnicities.

METHODS

We conducted a cross-sectional study to examine the associations of 282 GWAS-identified single nucleotide polymorphisms with three BMI-related traits, current BMI, BMI at 20 years old (BMI at 20), and change in BMI (BMI change), among 11,586 Japanese individuals enrolled in the Japan Multi-Institutional Collaborative Cohort study. Associations were examined using multivariable linear regression models.

RESULTS

We found a significant association (P < 0.05/282 = 1.77 × 10-4) between BMI and 11 polymorphisms in or near FTO, BDNF, TMEM18, HS6ST3, and BORCS7. The trend was similar between current BMI and BMI change, but differed from that of the BMI at 20. Among the significant variants, those on FTO were associated with all BMI traits, whereas those on TMEM18 and HS6SR3 were only associated with BMI at 20. The association of FTO loci with BMI remained, even after additional adjustment for dietary energy intake.

CONCLUSIONS

Previously reported BMI-associated loci discovered in Europeans were also identified in the Japanese population. Additionally, our results suggest that the effects of each loci on BMI may vary across the life course and that this variation may be caused by the differential effects of individual genes on BMI via different pathways.

Relationship between non-fasting triglycerides and cardiovascular disease mortality in a 20-year follow-up study of a Japanese general population: NIPPON DATA90

Background

Non-fasting triglycerides (TG) are considered a better predictor of cardiovascular disease (CVD) than fasting TG. However, the effect of non-fasting TG on fatal CVD events remains unclear. In the present study, we aimed to explore the relationship between non-fasting TG and CVD mortality in a Japanese general population.

Methods

A total of 6,831 participants without a history of CVD, in which those who had a blood sampling over 8 hours or more after a meal were excluded, were followed for 18.0 years. We divided participants into seven groups according to non-fasting TG levels: ≤59 mg/dL, 60–89 mg/dL, 90–119 mg/dL, 120–149 mg/dL, 150–179 mg/dL, 180–209 mg/dL, and ≥210 mg/dL, and estimated the multivariable-adjusted hazard ratios (HRs) of each TG group for CVD mortality after adjusting for potential confounders, including high density lipoprotein cholesterol. Additionally, we performed analysis stratified by age <65 and ≥65 years.

Results

During the follow-up period, 433 deaths due to CVD were detected. Compared with a non-fasting TG of 150–179 mg/dL, non-fasting TG ≥210 mg/dL was significantly associated with increased risk for CVD mortality (HR 1.56: 95% CI, 1.01–2.41). Additionally, lower levels of non-fasting TG were also significantly associated with increased risk for fatal CVD. In participants aged ≥65 years, lower levels of non-fasting TG had a stronger impact on increased risk for CVD mortality, while higher levels of non-fasting TG had a stronger impact in those aged <65 years.

Conclusion

In a general Japanese population, we observed a U-shaped association between non-fasting TG and fatal CVD events.

A genome-wide association study in Japanese identified one variant associated with a preference for a Japanese dietary pattern

BACKGROUND/OBJECTIVES

Individual eating habits may be influenced by genetic factors, in addition to environmental factors. Previous studies suggested that adherence to Japanese food patterns was associated with a decreased risk of all-cause and cardiovascular disease mortality. We conducted a genome-wide association study (GWAS) in a Japanese population to find genetic variations that affect adherence to a Japanese food pattern.

SUBJECTS/METHODS

We analyzed GWAS data using 14,079 participants from the Japan Multi-Institutional Collaborative Cohort study. We made a Japanese food score based on six food groups. Association of the imputed variants with the Japanese food score was performed by linear regression analysis with adjustments for age, sex, total energy intake, alcohol intake (g/day), and principal components 1-10 omitting variants in the major histocompatibility region.

RESULTS

We found one SNP in the 14q11.2 locus that was significantly associated with the Japanese food score with P values <5 × 10^-8. Functional annotation revealed that the expression levels of two genes (BCL2L2, SLC22A17) were significantly inversely associated with this SNP. These genes are known to be related to olfaction and obesity.

CONCLUSION

We found a new SNP that was associated with the Japanese food score in a Japanese population. This SNP is inversely associated with genes link to olfaction and obesity.

Association between alcohol intake pattern and metabolic syndrome components and simulated change by alcohol intake reduction: A cross-sectional study from the Japan Multi-Institutional Collaborative Cohort Study

To investigate the association between alcohol intake pattern in amount and frequency and metabolic syndrome (Mets) components, we simulated the change in the prevalence of Mets components by intake reduction. In order to manage Mets, alcohol intake reduction with moderation of intake pattern is required. However, evidence investigating the comparative impact of alcohol intake reduction in amount and frequency for Mets components is limited. We conducted a large-scale cross-sectional study in the general Japanese population. The study subjects included 37,371 non-drinkers and current drinkers recruited in the Japan Multi-Institutional Collaborative Cohort Study. Odds ratios (ORs) for Mets components according to alcohol intake amount and frequency were estimated using a multiple logistic regression model. The prevalence of Mets components was estimated after assumed alcohol intake reduction of a) none, b) 10 g/day (men) or 5 g/day (women), c) 20 g/day (men) or 10 g/day (women), d) less than 20 g/day (men) or 10 g/day (women) for moderate-to-heavy drinkers, e) 1-2 times/week, and f) 3-4 times/week. The ORs with alcohol intake amount and frequency increased with high blood pressure while decreasing with dyslipidemia. A J-shaped association was observed between intake amount and Mets. The estimated prevalence (%) of high blood pressure and dyslipidemia in men were a) 45.2, b) 43.0, c) 41.4, d) 40.4, e) 42.9, and f) 42.0; and a) 50.3, b) 51.8, c) 52.9, d) 50.2, e) 52.7, and f) 53.4 in women. The estimated prevalence of high blood pressure in women did not evidently decrease. Simulated alcohol intake reduction showed decreased prevalence for high blood pressure and increased prevalence for dyslipidemia in men after reduced intake amount and frequency. The largest decreased prevalence for high blood pressure was observed in men when all moderate-to-heavy drinkers reduced their alcohol intake amount to less than 20 g/day.

Exercise Habits Are Associated with Improved Long-Term Mortality Risks in the Nationwide General Japanese Population: A 20-Year Follow-Up of the NIPPON DATA90 Study

Exercise habits are known as a protective factor for a variety of diseases and thus recommended worldwide; however, few studies have examined long-term effects of exercise habits on mortality. We continuously monitored death status in a nationwide population sample of 7,709 eligible persons from the National Integrated Project for Prospective Observation of Noncommunicable Disease and its Trends in the Aged in 1990 (NIPPON DATA90), for which baseline data were obtained in 1990. To investigate the long-term impact of baseline exercise habits, we calculated the relative risk of non-exercisers (participants without regular voluntary exercise habits) in reference to exercisers (those with these habits) for all-cause or cause-specific mortality using a Cox proportional hazard model, in which the following confounding factors were appropriately adjusted: sex, age, body mass index, total energy intake, smoking, drinking, and history of cardiovascular disease. During a median 20 years of follow-up, 1,747 participants died, 99 of heart failure. The risk for all-cause mortality was 12% higher in non-exercisers than in exercisers (95% confidence interval, 1%-24%), which was also observed for mortality from heart failure, as 68% higher in non-exercisers than in exercises (95% confidence interval, 3%-173%). These associations were similarly observed when the participants were divided to subgroups by sex, age, and the light, moderate, or vigorous intensity of physical activity, without any significant heterogeneities (P > 0.1). The present study has revealed significant impact of exercise habits on long-term mortality risks, supporting worldwide recommendations for improvement of exercise habits.

Long-Term Survival after Stroke in 1.4 Million Japanese Population: Shiga Stroke and Heart Attack Registry

Background and Purpose

Although numerous measures for stroke exist, stroke remains one of the leading causes of death in Japan. In this study, we aimed to determine the long-term survival rate after first-ever stroke using data from a large-scale population-based stroke registry study in Japan.

Methods

Part of the Shiga Stroke and Heart Attack Registry, the Shiga Stroke Registry is an ongoing population-based registry study of stroke, which covers approximately 1.4 million residents of Shiga Prefecture in Japan. A total 1,880 patients with non-fatal first-ever stroke (among 29-day survivors after stroke onset) registered in 2011 were followed up until December 2016. Five-year cumulative survival rates were estimated using the Kaplan-Meier method, according to subtype of the index stroke. Cox proportional hazards models were used to assess predictors of subsequent all-cause death.

Results

During an average 4.3-year follow-up period, 677 patients died. The 5-year cumulative survival rate after non-fatal first-ever stroke was 65.9%. Heterogeneity was present in 5-year cumulative survival according to stroke subtype: lacunar infarction, 75.1%; large-artery infarction, 61.5%; cardioembolic infarction, 44.9%; intracerebral hemorrhage, 69.1%; and subarachnoid hemorrhage, 77.9%. Age, male sex, Japan Coma Scale score on admission, and modified Rankin Scale score before stroke onset were associated with increased mortality during the chronic phase of ischemic and hemorrhagic stroke.

Conclusions

In this study conducted in a real-world setting of Japan, the 5-year survival rate after non-fatal first-ever stroke remained low, particularly among patients with cardioembolic infarction and large-artery infarction in the present population-based stroke registry.

Study profile of the Japan Multi-institutional Collaborative Cohort (J-MICC) Study

BACKGROUND

The Japan Multi-institutional Collaborative Cohort (J-MICC) study was launched in 2005 to examine gene-environment interactions in lifestyle-related diseases, including cancers, among the Japanese. This report describes the study design and baseline profile of the study participants.

METHODS

The participants of the J-MICC Study were individuals aged 35 to 69 years enrolled from respondents to study announcements in specified regions, inhabitants attending health checkup examinations provided by local governments, visitors at health checkup centers, and first-visit patients at a cancer hospital in Japan. At the time of the baseline survey, from 2005 to 2014, we obtained comprehensive information regarding demographics, education, alcohol consumption, smoking, sleeping, exercise, food intake frequency, medication and supplement use, personal and family disease history, psychological stress, and female reproductive history, and collected peripheral blood samples.

RESULTS

The baseline survey included 92,610 adults (mean age: 55.2 [9.4] years, 44.1% men) from 14 study regions in 12 prefectures. The participation rate was 33.5%, with participation ranging from 19.7% to 69.8% in different study regions. The largest number of participants was in the age groups of 65-69 years for men and 60-64 years for women. There were differences in body mass index, educational attainment, alcohol consumption, smoking, and sleep duration between men and women.

CONCLUSIONS

The J-MICC Study collected lifestyle and clinical data and biospecimens from over 90,000 participants. This cohort is expected to be a valuable resource for the national and international scientific community in providing evidence to support longer healthy lives.

Abstract 3486: Body mass index and colorectal cancer risk in Japanese populations: a Mendelian randomization study

Background: Prospective cohort studies have shown a positive association between body mass index (BMI) and the risk of colorectal cancer (CRC). However, limitations inherent in traditional observational studies, such as reverse causality and residual confounding, might explain the association. To overcome these limitations, Mendelian randomization (MR) studies of the BMI-CRC association have been conducted in European and U.S. groups, but the association remains to be clarified in East Asians. Purpose: We performed MR analyses to investigate the causal association between BMI and CRC in Japanese populations.

Methods: Our study design consisted of 4 steps. (1) Based on a previous Genome-Wide Association Study in Japanese populations, we selected 68 BMI-associated single nucleotide polymorphisms (SNPs), which explained about 2.0% of the BMI variance, as instruments. (2) We examined the associations between 68 SNPs and BMI among general Japanese populations in the Japanese Consortium of Genetic Epidemiology studies (N=36,253). (3) We performed a fixed-effect meta-analysis to investigate associations between 68 SNPs and CRC using individual-level data and publicly available summary-statistic data of Japanese populations (cases=7,473, controls=33,322). (4) Finally, we used the inverse-variance weighted (IVW) method to calculate MR estimates. Several sensitivity analyses were applied to assess robustness or horizontal pleiotropy using weighted median, weighted mode, MR-Egger regression, and MR-Pleiotropy Residual Sum and Outlier (PRESSO) methods.

Results: In the main analysis using the IVW method, a one-unit increase in BMI was associated with an odds ratio of 1.12 (95% confidence interval [CI]: 1.06-1.20) for CRC. Sensitivity analyses consistently showed increased odds ratios for CRC per one-unit increase in BMI. The odds ratios for weighted median, weighted mode, and MR-Egger regression were 1.16 (95% CI: 1.06-1.27), 1.14 (95% CI: 1.05-1.24), and 1.10(95% CI: 0.98-1.23), respectively. The MR-Egger intercept P-value was 0.63. No outlier was detected using the MR-PRESSO method.

Conclusions: Our MR analyses provide evidence that BMI is positively associated with CRC in Japanese populations. Our findings seem to suggest that MR estimates for the BMI-CRC association may be consistent across different ethnicities.

Citation Format: Shiori Suzuki, Atsushi Goto, Masahiro Nakatochi, Akira Narita, Taiki Yamaji, Norie Sawada, Ryoko Katagiri, Tsuyoshi Hachiya, Yoichi Sutoh, Isao Oze, Yuriko Koyanagi, Yumiko Kasugai, Hidemi Ito, Hiroaki Ikezaki, Keitaro Tanaka, Takashi Tamura, Haruo Mikami, Toshiro Takezaki, Sadao Suzuki, Nagato Kuriyama, Kiyonori Kuriki, Yoshikuni Kita, Kokichi Arisawa, Kenji Takeuchi, Kozo Tanno, Atsushi Shimizu, Gen Tamiya, Atsushi Hozawa, Kengo Kinoshita, Kenji Wakai, Makoto Sasaki, Masayuki Yamamoto, Keitaro Matsuo, Shoichiro Tsugane, Motoki Iwasaki. Body mass index and colorectal cancer risk in Japanese populations: a Mendelian randomization study [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3486.

Two-Year Recurrence After First-Ever Stroke in a General Population of 1.4 Million Japanese Patients - The Shiga Stroke and Heart Attack Registry Study

BACKGROUND

Despite many effective strategies for the prevention of recurrent stroke, individuals who survive an initial stroke have been shown to be at high risk of recurrent stroke. The aim of this study was to investigate the current status of stroke recurrence after first-ever stroke using a population-based stroke registry in Japan.Methods and Results:As part of the Shiga Stroke and Heart Attack Registry, the Shiga Stroke Registry is an ongoing population-based stroke registry study that covers approximately 1.4 million residents of Shiga Prefecture, Japan. A total of 1,883 first-ever stroke survivors at 28 days was registered in 2011 and followed-up until the end of 2013. Recurrence was defined as any type of stroke after 28 days from the onset of an index event. Two-year cumulative recurrence rates were estimated using cumulative incidence function methods. Over a mean 2.1-year follow-up period, 120 patients experienced recurrent stroke and 389 patients died without recurrence. The 2-year cumulative recurrence rate was higher in patients with index ischemic stroke (6.8%) than in those with index hemorrhagic stroke (3.8%).

CONCLUSIONS

Two-year cumulative recurrence rate after first-ever stroke remained high, particularly among patients with ischemic stroke, in the present population-based registry study in a real-world setting in Japan. Further intensive secondary prevention strategies are required for these high-risk individuals.

Challenges in a population-based registry of cardiovascular disease in Shiga, Japan

Background

Stroke and cardiovascular disease are one of the leading causes of death and disability in Japan. In order to investigate current burden, we conduct a population-based registry of cardiovascular disease in Shiga Prefecture, Japan since 2012. We will demonstrate challenges in conduct of the registry study.

Methods

In 2012, we established the Shiga Stroke Registry (SSR), a multicenter population-based registry study designed to build a complete information system for the management of stroke in Shiga Prefecture, Japan. The registry uses local monitoring, combined with remote data collection and quality control systems, to create an integrated surveillance system among a network of all acute care hospitals with neurology/neurosurgery facilities and smaller hospitals with rehabilitation facilities in the region. In 2019, study name has changed to Shiga Stroke and Heart Attack Registry (SSHR) and additional registration of coronary heart disease and aortic disease have started. Each case is reviewed and adjudicated by 2 or more specialists.

Results

In the financial year of 2018 (from April to March), a total of 4809 stroke cases were identified. From December 2018 to April 2019, a total of 515 coronary heart and aortic diseases were identified. A total 10 nurses work full-time for the registry and it takes average of 1 hour to collect information for each patient. Challenges in conduct of the cardiovascular registry involve regulatory and ethical approval, funding, associations with local hospitals, non-standardized hospital diagnosis, staff training for comprehensive data collection including pathophysiology, examination and treatment, and quality control of data collection.

Conclusions

SSHR is a population-based registry of wide range of stroke and cardiovascular disease in Shiga Prefecture, Japan. In order to keep quality of the data, we put a lot of efforts on staff training and quality control.

Key messages

Population-based registry of wide range of stroke and cardiovascular disease in Shiga, Japan. In order to keep quality of the data, we put a lot of efforts on staff training and quality control.

Genome-wide meta-analysis identifies multiple novel loci associated with serum uric acid levels in Japanese individuals

Gout is a common arthritis caused by elevated serum uric acid (SUA) levels. Here we investigated loci influencing SUA in a genome-wide meta-analysis with 121,745 Japanese subjects. We identified 8948 variants at 36 genomic loci (P<5 × 10-8) including eight novel loci. Of these, missense variants of SESN2 and PNPLA3 were predicted to be damaging to the function of these proteins; another five loci-TMEM18, TM4SF4, MXD3-LMAN2, PSORS1C1-PSORS1C2, and HNF4A-are related to cell metabolism, proliferation, or oxidative stress; and the remaining locus, LINC01578, is unknown. We also identified 132 correlated genes whose expression levels are associated with SUA-increasing alleles. These genes are enriched for the UniProt transport term, suggesting the importance of transport-related genes in SUA regulation. Furthermore, trans-ethnic meta-analysis across our own meta-analysis and the Global Urate Genetics Consortium has revealed 15 more novel loci associated with SUA. Our findings provide insight into the pathogenesis, treatment, and prevention of hyperuricemia/gout.

Abstract TP219: Two-Year Recurrence After First-Ever Stroke in a General Population of 1.4 Million Japanese: Shiga Stroke Registry

Introduction: Despite many effective strategies for the secondary prevention of stroke, individuals who survived an initial stroke have been shown to be at high risk of recurrent stroke. The aim of the present analysis is to investigate the current status of stroke recurrence after first-ever stroke using data from a large-scale population-based stroke registry in Japan.

Methods: Shiga Stroke Registry is an ongoing population-based registry of stroke, which covers approximately 1.4 million residents of the Shiga prefecture in central Japan (located central part of Honshu Island). There is an integrated surveillance system involving the registration of cases among a network of all acute care hospitals with neurology/neurosurgery facilities and smaller hospitals with rehabilitation facilities. A total of 2,176 first-ever stroke cases (1,398 cerebral infarction, 551 intracerebral hemorrhage, 227 others), who were registered in 2011, were followed up till December 2013. We defined recurrence as any type of stroke after 28days from the onset of index event. The 2-year cumulative recurrence rates were estimated using Kaplan-Meier method for total stroke cases and according to gender or subtypes of index stroke. The study has been approved by the Institutional Review Board of Shiga University of Medical Science.

Results: During a 2-year follow up period, 57 patients experienced recurrent stroke and 646 patients died without recurrence. One-year and two-year crude cumulative recurrence rates after first-ever stroke were 1.8% and 3.4%, respectively. Two-year crude cumulative recurrence rates were similar for men and women (3.4% vs 3.5%). Two-year crude cumulative recurrence rate was higher in patients with prior cerebral infarction (4.3%) than that in those with prior intracerebral hemorrhage (2.0%).

Conclusions: In the present population-based stroke registry with real-world setting in Japan, 2-year cumulative recurrence rate after first-ever stroke is still high, particularly among patients with a history of cerebral infarction. More intensive secondary prevention strategies are required for these high-risk individuals.

Abstract WP228: Seasonal Variation of Stroke Subtypes Incidence in Population-based Study in Shiga Prefecture, Japan

Introducution: Incidence rates of stroke have been shown to have seasonal variations. However, current evidence is limited for Japanese populations. The aim of this study was to investigate seasonal variation in incidence of stroke and its subtypes in a general population of 1.4 million Japanese.

Methods: Shiga Stroke Registry is an ongoing population-based registry of stroke, which covers approximately 1.4 million residents of the Shiga prefecture in central Japan (located central part of Honshu Island). There is an integrated surveillance system involving the registration of cases among a network of all acute care hospitals with neurology/neurosurgery facilities and smaller hospitals with rehabilitation facilities. A total of 2,753 adult (18 years) cases of stroke (1838 ischemic stroke,713 intracerebral hemorrhage,196 subarachnoid hemorrhage and 6 other/unclassified), who were registered in 2011, were included in the present analysis. Incidence of stroke in each month of the year was estimated using 2011 vital statistics by a Poisson regression model with adjustment for age and gender.

Results: The age- and gender-adjusted incidence rates of total stroke were 180, 176, 177, 162, 163, 149, 134, 128, 133, 152, 144, 177per 100,000 person-years from January to December, respectively. Incidence rates in summer were lower in summer (July to September) than those in winter (December to February) or spring (March to May). Similar patterns were also observed for both ischemic stroke and intracerebral hemorrhage although seasonal variation was much more remarkable for intracerebral hemorrhage.There were no clear differences between summer and winter for incidence rates of subarachnoid hemorrhage.

Conlusions: Incidence rates of ischemic stroke and intracerebral hemorrhage seem to be high in winter and spring based on large-scale population-based stroke registry in Japan.

Association of exposure level to passive smoking with hypertension among lifetime nonsmokers in Japan: a cross-sectional study

Brief exposure to passive smoking immediately elevates blood pressure. However, little is known about the association between exposure to passive smoking and chronic hypertension. We aimed to examine this association in a cross-sectional study, after controlling multiple potential confounders.Participants included 32,098 lifetime nonsmokers (7,216 men and 24,882 women) enrolled in the Japan Multi-Institutional Collaborative Cohort Study. Passive smoking was assessed using a self-administered questionnaire. The single question about exposure to passive smoking had five response options: "sometimes or almost never," "almost every day, 2 hours/day or less," "almost every day, 2 to 4 hours/day," "almost every day, 4 to 6 hours/day," and "almost every day, 6 hours/day or longer." Hypertension was defined as any of the following: systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥90 mmHg, or use of antihypertensive medication. Multivariate-adjusted odds ratio (OR) and 95% confidence interval (CI) for hypertension were estimated by exposure level to passive smoking using unconditional logistic regression models.The multivariate-adjusted OR for hypertension in those exposed almost every day was 1.11 (95% CI: 1.03-1.20) compared with those exposed sometimes or almost never. The OR for a 1-hour per day increase in exposure was 1.03 (95% CI: 1.01-1.06, Pfor trend = .006). This association was stronger in men than in women; the ORs were 1.08 (95% CI: 1.01-1.15, Pfor trend = .036) and 1.03 (95% CI: 1.00-1.05, Pfor trend = .055), respectively.Our findings suggest importance of tobacco smoke control for preventing hypertension.

Two-Year Survival After First-Ever Stroke in a General Population of 1.4 Million Japanese - Shiga Stroke Registry

BACKGROUND

Stroke is one of the leading causes of disability and mortality in Japan. The aim of the present analysis was to determine the non-acute survival rate after first-ever stroke using data from a large-scale population-based stroke registry in Japan. Methods and Results: Shiga Stroke Registry is an ongoing population-based registry of stroke, which covers approximately 1.4 million residents of Shiga Prefecture in central Japan. A total of 2,176 first-ever stroke patients, who were registered in 2011, were followed up until December 2013. The 2-year cumulative survival rates were estimated using Kaplan-Meier method according to index stroke subtype. Cox proportional hazards models were used to assess predictors of all-cause death. During a 2-year follow-up period, 663 patients (30.5%) died. The 2-year cumulative survival rate after first-ever stroke was 69.5%. There was heterogeneity in 2-year cumulative survival according to stroke subtype: lacunar infarction, 87.2%; large artery infarction, 76.1%; cardioembolic infarction, 55.4%; intracerebral hemorrhage, 65.9%; and subarachnoid hemorrhage, 56.7%. Older age, male sex, medical history, higher Japan coma scale score on admission, and stroke subtype were associated with risk of all-cause death in ≤2 years.

CONCLUSIONS

In the present population-based stroke registry with a real-world setting in Japan, 2-year cumulative mortality after first-ever stroke is still high (>30%), particularly for cardioembolic infarction, subarachnoid hemorrhage and intracerebral hemorrhage.

The Association between Glomerular Filtration Rate Estimated on Admission and Acute Stroke Outcome: The Shiga Stroke Registry

AIM

Although renal dysfunction has been identified as a novel risk factor affecting stroke prognosis, few have analyzed the association within large-scale population-based setting, using wide-range estimated glomerular filtration rate (eGFR) category. We aimed to determine the association of admission eGFR with acute stroke outcomes using data from a registry established in Shiga Prefecture, Japan.

METHODS

Following exclusion of patients younger than 18 years, with missing serum creatinine data, and with onset more than 7 days prior to admission, 2,813 acute stroke patients registered in the Shiga Stroke Registry year 2011 were included in the final analysis. The Japanese Society of Nephrology equation was used to estimate GFR. Multivariable logistic regression was performed to analyze the association of eGFR with all-cause in-hospital death (modified Rankin Scale [mRS] 6), and at-discharge death/disability (mRS 2-6). Separate analyses were conducted within stroke subtypes.

RESULTS

Compared to eGFR 60-89 mL/min/1.73 m2, adjusted odds ratios (ORs) and 95% confidence interval [95% CI] for in-hospital death (in the order of eGFR ＜45, 45-59, and ≥90 mL/min/1.73 m2) were 1.54 [1.04-2.27], 1.07 [0.72-1.58], and 1.04 [0.67-1.59]. Likewise, adjusted ORs [95% CI] for at-discharge death/disability were 1.54 [1.02-2.32], 0.97 [0.73-1.31], and 1.48 [1.06-2.05]. Similar pattern was further evident in the eGFR ＜45 mL/min/1.73 m2 group for both outcomes within acute ischemic stroke patients.

CONCLUSIONS

Our study has ascertained that in acute stroke, particularly ischemic stroke, low eGFR was significantly associated with in-hospital death and at-discharge death/disability. Additionally, high eGFR was found to be associated with at-discharge death/disability.

Sex-specific relevance of diabetes to occlusive vascular and other mortality: a collaborative meta-analysis of individual data from 980 793 adults from 68 prospective studies

BACKGROUND

Several studies have shown that diabetes confers a higher relative risk of vascular mortality among women than among men, but whether this increased relative risk in women exists across age groups and within defined levels of other risk factors is uncertain. We aimed to determine whether differences in established risk factors, such as blood pressure, BMI, smoking, and cholesterol, explain the higher relative risks of vascular mortality among women than among men.

METHODS

In our meta-analysis, we obtained individual participant-level data from studies included in the Prospective Studies Collaboration and the Asia Pacific Cohort Studies Collaboration that had obtained baseline information on age, sex, diabetes, total cholesterol, blood pressure, tobacco use, height, and weight. Data on causes of death were obtained from medical death certificates. We used Cox regression models to assess the relevance of diabetes (any type) to occlusive vascular mortality (ischaemic heart disease, ischaemic stroke, or other atherosclerotic deaths) by age, sex, and other major vascular risk factors, and to assess whether the associations of blood pressure, total cholesterol, and body-mass index (BMI) to occlusive vascular mortality are modified by diabetes.

RESULTS

Individual participant-level data were analysed from 980 793 adults. During 9·8 million person-years of follow-up, among participants aged between 35 and 89 years, 19 686 (25·6%) of 76 965 deaths were attributed to occlusive vascular disease. After controlling for major vascular risk factors, diabetes roughly doubled occlusive vascular mortality risk among men (death rate ratio [RR] 2·10, 95% CI 1·97-2·24) and tripled risk among women (3·00, 2·71-3·33; χ2 test for heterogeneity p<0·0001). For both sexes combined, the occlusive vascular death RRs were higher in younger individuals (aged 35-59 years: 2·60, 2·30-2·94) than in older individuals (aged 70-89 years: 2·01, 1·85-2·19; p=0·0001 for trend across age groups), and, across age groups, the death RRs were higher among women than among men. Therefore, women aged 35-59 years had the highest death RR across all age and sex groups (5·55, 4·15-7·44). However, since underlying confounder-adjusted occlusive vascular mortality rates at any age were higher in men than in women, the adjusted absolute excess occlusive vascular mortality associated with diabetes was similar for men and women. At ages 35-59 years, the excess absolute risk was 0·05% (95% CI 0·03-0·07) per year in women compared with 0·08% (0·05-0·10) per year in men; the corresponding excess at ages 70-89 years was 1·08% (0·84-1·32) per year in women and 0·91% (0·77-1·05) per year in men. Total cholesterol, blood pressure, and BMI each showed continuous log-linear associations with occlusive vascular mortality that were similar among individuals with and without diabetes across both sexes.

INTERPRETATION

Independent of other major vascular risk factors, diabetes substantially increased vascular risk in both men and women. Lifestyle changes to reduce smoking and obesity and use of cost-effective drugs that target major vascular risks (eg, statins and antihypertensive drugs) are important in both men and women with diabetes, but might not reduce the relative excess risk of occlusive vascular disease in women with diabetes, which remains unexplained.

FUNDING

UK Medical Research Council, British Heart Foundation, Cancer Research UK, European Union BIOMED programme, and National Institute on Aging (US National Institutes of Health).