Japanese Population-based Cohort Research Articles

Fatty Liver Index and the Risk of Atrial Fibrillation in a General Japanese Population - The Suita Study.

Atrial fibrillation (AF) is the most diagnosed arrhythmia in clinical settings. The fatty liver index (FLI) is a marker of liver steatosis with potential cardiovascular implications. This study investigated whether FLI could predict the risk of AF.Methods and Results: We used data from the Suita Study, a Japanese population-based prospective cohort study. A total of 2,346 men and 3,543 women, aged 30-84 years, without prevalent AF were included and followed up. The diagnosis of AF was established during follow-up using electrocardiograms, hospital records, and death certificates. FLI was assessed during a baseline health checkup. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated for incident AF per FLI quintile and log-transformed FLI. Within a median 14.5 years of follow-up, 142 men and 105 women developed AF. Compared with women in the third (middle) FLI quintile, women in the first (lowest), fourth, and fifth (highest) quintiles showed a higher risk of AF, with multivariable-adjusted HRs of 2.37 (95% CI 1.06-5.31), 2.60 (95% CI 1.30-5.17), and 2.04 (95% CI 1.00-4.18), respectively. No corresponding associations were observed in men. The change in log-transformed FLI was not associated with the risk of AF in either sex. A U-shaped association between FLI and AF risk was detected in Japanese women. FLI could be a screening tool to detect women at high risk of developing AF.

Liver Enzymes and the Risk of Stroke among the General Japanese Population: A Prospective Cohort Study

Introduction: Stroke is a major cause of morbidity and mortality. Liver enzymes, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyl transpeptidase (GGT), are markers of liver diseases with potential cardiovascular implications. This study aimed to investigate the prospective association between liver enzymes and stroke risk. Methods: We analyzed data from 3,379 men and 4,007 women without cardiovascular disease and registered in the Suita Study, a Japanese population-based prospective cohort study. The hazard ratios (HRs) and 95% confidence intervals (95% CIs) of stroke risk were estimated per quintiles of ALT, AST, and GGT in men and women. Results: Within a median follow-up period of 16.7 years, 438 incident stroke events were diagnosed. In men, compared to the second quintiles, the fifth (highest) quintiles of liver enzymes showed increased stroke risks: HRs (95% CIs) = 2.07 (1.35, 3.18) in ALT, 1.66 (1.10, 2.53) in AST, and 1.76 (1.11, 2.81) in GGT. The associations did not change with cerebral infarction risk: HRs (95% CIs) = 2.09 (1.24, 3.50) in ALT, 1.84 (1.11, 3.06) in AST, and 1.74 (1.00, 3.04) in GGT. The lowest ALT, AST, and GGT quintiles tended to show increased stroke and cerebral infarction risks, yet these associations were statistically insignificant. No such associations were shown in women. Conclusion: Elevated ALT, AST, and GGT levels were associated with increased stroke and cerebral infarction risks among Japanese men.

Prevalence, Associated Factors, and Inter-Eye Differences of Refractive Errors in a Population-Based Japanese Cohort: The Tohoku Medical Megabank Eye Study

ABSTRACT Purpose To investigate the prevalence, associated factors, and inter-eye differences of myopia and astigmatism in an adult Japanese population-based cohort. Methods A total of 4282 participants from the Tohoku Medical Megabank Organization Eye Study (ToMMo Eye Study) underwent comprehensive ocular examinations as well as extensive physiological tests and a lifestyle questionnaire. The spherical equivalent (SE) and cylinder power were obtained as refractive parameters. The age- and gender-stratified prevalences of high myopia (SE < −5D), myopia (SE < −0.5D), hyperopia (SE > 0.5D), astigmatism (cylinder power < −0.5D), and anisometropia (SE difference >1D) were calculated. Multivariable analyses were performed to identify associated factors for refractive error (RE). Distribution and associated factors of the inter-eye difference in RE were also investigated. Results The age-adjusted prevalence of high myopia, myopia, hyperopia, astigmatism, and anisometropia was 15.9%, 63.5%, 14.7%, 51.1%, and 14.7%, respectively. Both myopia and high myopia were more prevalent in the younger age group, while astigmatism was more prevalent in the older age group. Age, education, blood pressure, intraocular pressure, and corneal thickness are significantly associated with myopic refraction. Age, gender, intraocular pressure, and corneal thickness are correlated with astigmatism. Older age was associated with against-the-rule astigmatism. Older age, myopia, and longer education showed a significant correlation with large inter-eye differences in SERE. Conclusions This study demonstrated the high prevalence of myopia in young Japanese, which may be caused by a generational shift. This study also confirmed the influence of age and education on both the prevalence and inter-eye differences of RE.

Association between low back pain and psychological stress response in a Japanese population-based study

BackgroundPsychological stress response refers to the negative emotional states generated when an individual perceives that they do not have the resources to cope with or respond to a threat. Low back pain (LBP) is a complex condition with multiple contributors, including psychological factors. However, whether LBP is a stressor that causes a psychological stress response remains unknown. This study aimed to investigate the association between LBP and psychological stress response in a Japanese population-based cohort. MethodsParticipants aged >50 years were recruited from inhabitants of a mountain village in Japan. The participants completed the following patient-reported outcome measures. The extent of the psychological stress response was measured using the Stress response scale (SRS)-18, which includes the subscales “Depression/Anxiety”, “Irritability/Anger”, and “Helplessness”. LBP intensity in several situations/positions was measured using a numerical rating scale (NRS). Quality of life (QOL) was measured using the Oswestry Disability Index, EuroQol 5-dimension, and EuroQol visual analog scales. The association between SRS-18 and each parameter was statistically evaluated. ResultsA total of 282 participants (72.1 years old) were analyzed in this study, and 29.1% had chronic LBP. The SRS-18 total score of all participants ranged from 0 to 43, and the average SRS-18 total score was 7.7 ± 8.8 (depression/anxiety: 2.3 ± 3.2, irritability/anger: 2.4 ± 3.3, helplessness: 2.9 ± 3.2). SRS-18 scores of participants with LBP were significantly higher than those of participants without LBP. SRS-18 scores were significantly correlated with QOL scores (P < 0.01, correlation coefficient = 0.22–0.46). Multiple regression analysis showed that the NRS score of LBP during morning awakening was significantly associated with the SRS-18 total, depression/anxiety, and helplessness scores. ConclusionsPsychological stress responses were associated with LBP and LBP-related QOL among residents of a Japanese mountain village.

Genomics of perivascular space burden unravels early mechanisms of cerebral small vessel disease

Perivascular space (PVS) burden is an emerging, poorly understood, magnetic resonance imaging marker of cerebral small vessel disease, a leading cause of stroke and dementia. Genome-wide association studies in up to 40,095 participants (18 population-based cohorts, 66.3 ± 8.6 yr, 96.9% European ancestry) revealed 24 genome-wide significant PVS risk loci, mainly in the white matter. These were associated with white matter PVS already in young adults (N = 1,748; 22.1 ± 2.3 yr) and were enriched in early-onset leukodystrophy genes and genes expressed in fetal brain endothelial cells, suggesting early-life mechanisms. In total, 53% of white matter PVS risk loci showed nominally significant associations (27% after multiple-testing correction) in a Japanese population-based cohort (N = 2,862; 68.3 ± 5.3 yr). Mendelian randomization supported causal associations of high blood pressure with basal ganglia and hippocampal PVS, and of basal ganglia PVS and hippocampal PVS with stroke, accounting for blood pressure. Our findings provide insight into the biology of PVS and cerebral small vessel disease, pointing to pathways involving extracellular matrix, membrane transport and developmental processes, and the potential for genetically informed prioritization of drug targets.

Life satisfaction and the risk of atherosclerotic cardiovascular disease in the general Japanese population: the Suita Study.

Atherosclerotic cardiovascular disease (ASCVD) is a major cause of morbidity and mortality. Life satisfaction is a measure of mental health with a potential cardioprotective role. This study aimed to investigate the association between life satisfaction and ASCVD risk in the general Japanese population. We used data from 6,877 people (30-84 years) registered in the Suita Study, a Japanese population-based prospective cohort study. All participants were free from stroke and coronary heart disease (CHD) at baseline. Then, participants were followed up for incident ASCVD, including cerebral infarction and CHD. Cox proportional hazards models were used to calculate the hazard ratio (HR) and 95% confidence interval (95% CI) of incident ASCVD according to life satisfaction. Within 102,545 person-years (median follow-up = 16.6 years), 482 incident ASCVD events were identified. In the age- and sex-adjusted model, being very satisfied, rather satisfied, or not sure, compared to being dissatisfied with life, showed a lower risk of ASCVD: HR (95% CI) = 0.55 (0.41, 0.74), 0.67 (0.50, 0.89), and 0.57 (0.36, 0.88), respectively (p-trend < 0.001). The associations remained consistent after adjusting for stress and unfortunate events: HR (95% CI) = 0.57 (0.42, 0.77), 0.68 (0.50, 0.91), and 0.54 (0.35, 0.84), respectively (p-trend < 0.001). The results did not vary between cerebral infarction and CHD: HR (95% CI) for being very satisfied with life = 0.58 (0.37, 0.91) and 0.55 (0.36, 0.84), respectively. Life satisfaction was inversely associated with the risk of ASCVD in the investigated general Japanese population.

The long-term association between paternal involvement in infant care and children's psychological well-being at age 16 years: An analysis of the Japanese Longitudinal Survey of Newborns in the 21st Century 2001 cohort

BackgroundSome studies conducted in the United Kingdom have shown long-term associations between paternal involvement in childcare and adolescents' mental health issues. However, findings were inconsistent, and similar epidemiologic studies have not been conducted in other countries in Europe or Asia. Thus, we aimed to examine this association using Japanese population-based cohort study data. MethodsThe Japanese Longitudinal Survey of Newborns in the 21st Century commenced in 2001. Data from 18,568 16-year-olds enrolled in the survey were analyzed. Poor psychological well-being was assessed using the WHO-5 Well-being Index. Paternal involvement in childcare—in tasks such as changing diapers—was assessed at the children's 6 months of age. We created four groups from least involvement to most active involvement based on the frequency of fathers' performing the tasks. ResultsThe risk of poor psychological well-being was lower among more active involvement groups compared with the least involvement group, after adjusting for potential confounders (risk ratios = 0.90 [95 % confidence intervals: 0.85, 0.95] for the most active group). LimitationsDue to 16 years of follow-up, loss to follow-up may have caused a selection bias. ConclusionsOur study is the first in Asian countries to show that fathers' active involvement in childcare is associated with poor psychological well-being in adolescence. Encouraging fathers' involvement in childcare may ameliorate prevalent issues of school refusals and withdrawals in the long term in Japan.

Effectiveness and safety of chemotherapy for patients with malignant gastrointestinal obstruction: A Japanese population-based cohort study.

BACKGROUNDThe impacts of chemotherapy on patients with malignant gastrointestinal obstructions remain unclear, and multicenter evidence is lacking.AIMTo evaluate the effectiveness and safety of chemotherapy in patients with unresectable malignant gastrointestinal obstructions.METHODSWe conducted a multicenter retrospective cohort study that compared the chemotherapy group who received any chemotherapeutics after interventions, including palliative surgery or self-expandable metal stent placement, for unresectable malignant gastrointestinal obstruction vs the best supportive care (BSC) group between 2014 and 2019 in nine hospitals. The primary outcome was overall survival, and the secondary outcomes were patency duration and adverse events, including gastrointestinal perforation and gastrointestinal bleeding.RESULTSIn total, 470 patients in the chemotherapy group and 652 patients in the BSC group were analyzed. During the follow-up period of 54.1 mo, the median overall survival durations were 19.3 mo in the chemotherapy group and 5.4 mo in the BSC group (log-rank test, P < 0.01). The median patency durations were 9.7 mo [95% confidence interval (CI): 7.7-11.5 mo] in the chemotherapy group and 2.5 mo (95%CI: 2.0-2.9 mo) in the BSC group (log-rank test, P < 0.01). The perforation rate was 1.3% (6/470) in the chemotherapy group and 0.9% (6/652) in the BSC group (P = 0.567). The gastrointestinal bleeding rate was 1.5% (7/470) in the chemotherapy group and 0.5% (3/652) in the BSC group (P = 0.105).CONCLUSIONChemotherapy after interventions for unresectable malignant gastrointestinal obstruction was associated with increased overall survival and patency duration.

Cross-sectional associations between the types/amounts of beverages consumed and the glycemia status: The Japan Public Health Center-based Prospective Diabetes study

BackgroundThe associations between the types/amounts of beverages consumed in daily life and measures of the glycemia status were investigated in a Japanese population-based cohort. MethodsData from the baseline survey of the Japan Public Health Center-based Prospective Diabetes cohort were used. A cross-sectional analysis was performed in 3852 men and 6003 women who were evaluated under the fasting condition. The daily consumptions of coffee, green tea, oolong tea, black tea, soft drinks, fruit juices, or plain water were assessed using a self-reported questionnaire. Multivariable-adjusted linear regression analyses were performed using measures of the glycemia status (fasting plasma glucose (FPG) and glycated hemoglobin (HbA1c) ) as dependent variables and the types/amounts of beverages consumed as the independent variables, to calculate the differences according to the types/amounts of beverages consumed. ResultsIn the multivariable-adjusted models, coffee consumption of ≥240 mL/day was significantly associated with a change of the FPG level by −1.9 mg/dL in men (p = 0.013) and −1.4 mg/dL in women (p = 0.015), as compared to coffee consumption of 0 mL/day. No significant association of the FPG level was observed with any of the other types/amounts of beverages consumed. On the other hand, significant associations were found between the HbA1c levels and consumption of several types of beverages. ConclusionsHigh coffee consumption was associated with lower FPG levels in this Japanese population. Some unexpected associations of the HbA1c levels with the consumption of some types of beverages were observed, which need to be further investigated.

Survival following an out-of-hospital cardiac arrest in Japan in 2020 versus 2019 according to the cause.

AimThe coronavirus disease (COVID‐19) pandemic has led to an increase in out‐of‐hospital cardiac arrests (OHCAs) and mortality. However, there has been no reports in Japan using nationwide registry data. We compared survival among patients with OHCAs and detailed information on the cause during the COVID‐19 pandemic (2020), and during the pre‐pandemic period (2019).MethodsUsing a Japanese population‐based retrospective cohort study design, we analyzed registry data on 39,324 and 39,170 patients with OHCAs in 2019 and 2020, respectively. We compared patient outcomes in 2019 and 2020 using univariable and multivariable logistic regression analyses.ResultsThe proportion of OHCAs of cardiac origin increased significantly from 61.6% in 2019 to 62.7% in 2020 (P = 0.001). The use of bystander CPR (6.9% versus 5.7%, P < 0.001) and publicaccess automated external defibrillator pads (3.7% versus 3.0%, P < 0.001) decreased significantly from 2019 to 2020. The 1‐month survival for OHCA of cardiac origin (12.1% versus 10.7%; adjusted odds ratio [OR] 0.93, 95% confidence interval [CI] 0.87–1.00), asphyxia (10.9% versus 8.8%; adjusted OR 0.80, 95% CI 0.70–0.92), and external causes (adjusted OR 0.66; 95% CI 0.46–0.96), also decreased significantly from 2019 to 2020.ConclusionsIn Japan, the 1‐month survival after OHCA of cardiac origin, or due to asphyxia or external causes, decreased significantly during the COVID‐19 pandemic period.

Low-carbohydrate diet and risk of cancer incidence: The Japan Public Health Center-based prospective study.

Epidemiological evidence on the effects of a long‐term low‐carbohydrate diet (LCD) on cancer incidence remains sparse. We investigate the association between LCD and the risk of overall and specific cancer site incidence in a Japanese population‐based prospective cohort study among 90 171 participants aged 45‐74. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). During a median 17.0 y of follow‐up, we identified 15 203 cancer cases. A higher overall LCD score was associated with increased overall cancer risk (HR = 1.08 [CI: 1.02‐1.14], P‐trend = .012), while it was associated with decreased gastric cancer (GC) risk (0.81 [0.71‐0.93], P‐trend = .006). A higher animal‐based LCD score was associated with higher risk of overall cancer (1.08 [1.02‐1.14], P‐trend = .003), colorectal cancer (CRC) (1.11 [0.98‐1.25], P‐trend = .018), rectal cancer (RC) (1.24 [1.00‐1.54], P‐trend = .025), lung cancer (LC) (1.16 [1.00‐1.34], P‐trend = .042), and lower risk of GC (0.90 [0.79‐1.01], P‐trend = .033). Furthermore, we found that plant‐based LCD score was related to lower GC incidence (0.87 [0.77‐0.99], P‐trend = .031). Additionally, adjusted for plant fat intake amplified the adverse associations (overall cancer: 1.08 [1.02‐1.14] vs. 1.11 [1.05‐1.18]; CRC: 1.08 [0.95‐1.22] vs. 1.13 [0.99‐1.30]; LC: 1.14 [0.98‐1.33] vs. 1.19 [1.01‐1.41]). We conclude that LCD enriching with animal products was associated with increased overall cancer, CRC, and LC incidence. These adverse associations could be attenuated by plant fat consumption. LCD reduces the risk of developing GC. Long‐term adherence to LCD without paying attention to the balance between animal and plant food source consumption might cause adverse overall cancer incidence consequences.

Abstract 9502: Prehospital Variables Associated With Neurologically Intact Survival in Elderly Survivors After Out-of-Hospital Cardiac Arrest: Evidence from a Japanese Nationwide Population-based Cohort Study

Introduction: Prehospital variables associated with neurologically intact survival in elderly survivors after out-of-hospital cardiac arrest (OHCA) are unclear and could differ according to age. Methods: We evaluated 6,349 elderly patients with OHCA (age ≥ 65 years) of cardiac origin who achieved prehospital return of spontaneous circulation (ROSC) and survived for at least 1-month after OHCA. Data were obtained from the prospectively recorded All-Japan Utstein Registry between 2011 and 2016. Patients witnessed by emergency medical service providers were excluded. The primary outcome was 1-month neurologically intact survival, defined as a cerebral performance category (CPC) score of 1-2. Patients were divided into three groups by age (65-74, 75-89, or ≥ 90 years). The time from call receipt to ROSC was calculated. Results: The rates of 1-month CPC 1-2 in patients aged 65-74, 75-89, and ≥ 90 years were 66.5% (2,079/3,125), 52.9% (1,557/2,943), and 42.7% (120/281), respectively (p for trend &lt; 0.001). In multivariate logistic regression analysis, initial shockable rhythm and witnessed arrest were significantly associated with 1-month CPC 1-2 for all age groups (Table). However, the presence of bystander cardiopulmonary resuscitation (CPR) was significantly associated with 1-month CPC 1-2 only for patients aged 65-74 years. Time from call receipt to ROSC was not associated with 1-month CPC 1-2 for patients aged ≥ 90 years. In recursive partitioning analysis, the best single predictor for 1-month CPC 1-2 was initial shockable rhythm for all age groups. The next predictor for patients aged 65-74 years with initial shockable rhythm was the presence of bystander CPR, whereas the witnessed arrest was the next predictor for patients aged 65-74 years with initial non-shockable rhythm and other age groups regardless of the initial rhythm. Conclusions: Prehospital variables associated with neurologically intact survival in elderly survivors after OHCA varied with age.

Dose-response relationship between spino-pelvic alignment determined by sagittal modifiers and back pain-specific quality of life

PurposeTo determine whether abnormalities of the sagittal modifiers (SMs) of the Scoliosis Research Society (SRS)-Schwab classification truly reflect back pain (BP)-specific quality of life (QOL), it is necessary to examine their dose–response relationships and to determine clinically impactful thresholds for declines in BP-specific QOL. This study aimed to analyse the continuous dose–response relationship between each SM and BP-specific QOL.MethodsThis cross-sectional study, using data from a Japanese population-based cohort study, included 519 community-dwelling residents aged ≥ 50 years who participated in the annual health examination. The participants completed the Roland–Morris Disability Questionnaire (RDQ) on BP-specific QOL. Spino-pelvic alignment based on SMs was assessed by whole-spine X-ray examinations. We fitted general linear models with or without nonlinear terms to estimate the dose–response relationship between each SM and BP-specific QOL.ResultsPelvic tilt, pelvic incidence minus lumbar lordosis (PI-LL), and sagittal vertical axis showed dose–response relationships with BP-specific QOL measured as the RDQ score. PI-LL was most likely to predict a minimally clinically important RDQ score when its value exceeded the 90th percentile. A nonlinear relationship between PI-LL and the BP-specific QOL score was found. RDQ increased when PI-LL exceeded 10°.ConclusionPI-LL might be the most sensitive of the three modifiers of the SRS-Schwab classification for determining BP-specific QOL. Moreover, BP-specific QOL worsens rapidly when the compensatory mechanism against malalignment exceeds a critical value. Therefore, we suggest that traditional classifications and surgical strategies should be re-examined regarding the dose-dependent abnormalities of the SMs to develop a more reliable classification strategy.

Association between influenza and the incidence rate of new-onset type 1 diabetes in Japan.

ABSTRACTAimThis study aimed to determine whether there is an association between influenza and new‐onset type 1 diabetes.Materials and methodsThis population‐based retrospective cohort study used data from the National Database of Health Insurance Claims and Specific Health Check‐ups of Japan. Influenza was defined based on drug prescriptions and the onset of type 1 diabetes was defined using specific medical codes indicating a diagnosis of type 1 diabetes. The incidence rate ratio of new‐onset type 1 diabetes within 180 days after an influenza diagnosis was calculated and it was compared with that at other times using Poisson regression and generalized estimating equations. Sensitivity analyses were performed to confirm the robustness of this finding.ResultsThe data of 10,400 patients with new‐onset type 1 diabetes were analyzed, including 2,196 (952 male 1,244 female) patients diagnosed with influenza between 1 September 2014 and 31 August 2017. Although only patients with type 1 diabetes were included, adjusted analysis showed that individuals had a 1.3‐fold (95% confidence interval: 1.15–1.46) higher risk of developing type 1 diabetes in the first 180 days after influenza diagnosis than that at other times.ConclusionsIn this Japanese population‐based cohort, the risk of new‐onset type 1 diabetes may increase after the diagnosis of influenza. These results, which must be confirmed in other populations, suggest that influenza may be a causal factor for new‐onset type 1 diabetes. The molecular mechanisms underlying the potential etiological relationship between influenza and type 1 diabetes should be elucidated.

Abstract 309: Prediction Chart for Neurological Outcomes of Elderly Patients with Out-of-hospital Cardiac Arrest and the Corresponding Time to Termination of Resuscitation: Evidence from a Japanese Nationwide Population-based Cohort Study

Introduction: Neurological outcomes and the appropriate duration from call receipt to termination of resuscitation (TOR) in patients with out-of-hospital cardiac arrest (OHCA) could differ according to patient characteristics. Hypothesis: We hypothesized that a prediction chart comprising prehospital variables, including age, could be useful for predicting neurological outcomes and determining the time to TOR in the field or at the emergency department. Methods: We evaluated 19,829 elderly patients with OHCA (age ≥65 years) of cardiac origin who achieved prehospital return of spontaneous circulation (ROSC). Data were obtained from the prospectively recorded All-Japan Utstein Registry between 2011 and 2016. Patients with OHCA witnessed by emergency medical service providers were excluded. The primary outcome was 1-month neurologically intact survival, defined as a cerebral performance category (CPC) score of 1-2. Patients with OHCA were divided into 12 groups according to shockable rhythm (YES/NO), witness status (YES/NO), and age (65-74, 75-89, or ≥90 years). The time from call receipt to ROSC was calculated and categorized by 5-min intervals. The time from call receipt to ROSC at which the probability of 1-month CPC 1-2 decreased to &lt;1% was defined as the call to TOR duration. Results: The overall 1-month CPC 1-2 rate was 18.9% (n = 3,756). When stratified by patient characteristics, the 1-month CPC 1-2 rates ranged from 52.3% in patients aged 65-74 years with shockable rhythm and witnessed OHCA (best-case scenario) to 1.6% in patients aged ≥90 years with non-shockable rhythm and un-witnessed OHCA (worst-case scenario). The corresponding call to TOR duration ranged from 35 to 10 min (Table). Conclusions: Neurological outcomes and the appropriate call to TOR duration differed according to patient characteristics, including age. Our prediction chart for elderly patients with OHCA could be useful for determining TOR in the field or at the emergency department.

Population-based prevalence of femoroacetabular impingement in Japan

Objectives The prevalence of femoroacetabular impingement (FAI) was evaluated using a Japanese population-based cohort of participants aged ≥50 years. Methods Radiographs (n = 854) of bilateral hips of 427 participants (279 women, 148 men) were used for the analysis. The prevalence of cam type, pincer type, and mixed type FAI as well as osteoarthritis was evaluated. The association of FAI and osteoarthritis (OA), and pain were also evaluated. Results The prevalence of cam type and pincer type FAI were 4.2% and 20.3%, respectively. Mixed type FAI was 0.7%. OA was found in 4.0% of patients, and 17 hips (2.0%) with any FAI also had OA. A significant relationship between cam type FAI and OA was found, whereas no significant relationship between pincer type FAI and OA was seen. Sixty (7.0%) of all the hips were reported to be painful, and 14 of those painful hips (1.6%) had FAI. No significant relationship between FAI and hip pain was found. Conclusion We reported the first population-based prevalence of FAI in Japan. Radiological FAI was common, and pincer type was more common than cam type. The anatomical abnormalities associated with FAI, although often asymptomatic, are risk factors for OA.

Green tea consumption and mortality in Japanese men and women: a pooled analysis of eight population-based cohort studies in Japan.

The aim of our study was to assess the association between green tea consumption and all-cause and cause-specific mortality in a pooled analysis of eight Japanese population-based cohort studies. Pooled hazard ratios (HR) and 95% confidence intervals (CI), derived from random effects models, were used to evaluate the associations between green tea consumption, based on self-report at baseline, and risk of all-cause and cause-specific mortality. During a mean follow-up of 17.3years, among 313,381 persons, 52,943 deaths occurred. Compared with individuals who consumed < 1 cup/day, those in the highest consumption category (≥ 5 cups/day) had a decreased risk of all-cause mortality [the multivariate-adjusted HR was 0.90 (95% CI 0.87-0.94) for men and 0.82 (0.74-0.90) for women]. A similar inverse association was observed for heart disease mortality [HR 0.82 (0.75-0.90) for men, and 0.75 (0.68-0.84) for women], and cerebrovascular disease mortality [HR 0.76 (0.68-0.85) for men, and 0.78 (0.68-0.89) for women]. Among women, green tea consumption was associated with decreased risk of total cancer mortality: 0.89 (0.83-0.96) for the 1-2 cups/day category and 0.91 (0.85-0.98) for the 3-4 cups/day category. Results for respiratory disease mortality were [HR 0.75 (0.61-0.94)] among 3-4 cup daily consumers and [HR 0.66 (0.55-0.79)] for ≥ 5 cups/day. Higher consumption of green tea is associated with lower risk for all-cause mortality in Japanese, especially for heart and cerebrovascular disease. Moderate consumption decreased the risk of total cancer and respiratory disease mortality in women.

Genome-Wide Association Study of Renal Function Traits: Results from the Japan Multi-Institutional Collaborative Cohort Study

Background: Chronic kidney disease (CKD) is a rapidly growing, worldwide public health problem. Recent advances in genome-wide-association studies (GWAS) revealed several genetic loci associated with renal function traits worldwide. Methods: We investigated the association of genetic factors with the levels of serum creatinine (SCr) and the estimated glomerular filtration rate (eGFR) in Japanese population-based cohorts analyzing the GWAS imputed data with 11,221 subjects and 12,617,569 variants, and replicated the findings with the 148,829 hospital-based Japanese subjects. Results: In the discovery phase, 28 variants within 4 loci (chromosome [chr] 2 with 8 variants including rs3770636 in the LDL receptor related protein 2 gene locus, on chr 5 with 2 variants including rs270184, chr 17 with 15 variants including rs3785837 in the BCAS3 gene locus, and chr 18 with 3 variants including rs74183647 in the nuclear factor of ­activated T-cells 1 gene locus) reached the suggestive level of p < 1 × 10^–6 in association with eGFR and SCr, and 2 variants on chr 4 (including rs78351985 in the microsomal triglyceride transfer protein gene locus) fulfilled the suggestive level in association with the risk of CKD. In the replication phase, 25 variants within 3 loci (chr 2 with 7 variants, chr 17 with 15 variants and chr 18 with 3 variants) in association with eGFR and SCr, and 2 variants on chr 4 associated with the risk of CKD became nominally statistically significant after Bonferroni correction, among which 15 variants on chr 17 and 3 variants on chr 18 reached genome-wide significance of p < 5 × 10^–8 in the combined study meta-analysis. The associations of the loci on chr 2 and 18 with eGFR and SCr as well as that on chr 4 with CKD risk have not been previously reported in the Japanese and East Asian populations. Conclusion: Although the present GWAS of renal function traits included the largest sample of Japanese participants to date, we did not identify novel loci for renal traits. However, we identified the novel associations of the genetic loci on chr 2, 4, and 18 with renal function traits in the Japanese population, suggesting these are transethnic loci. Further investigations of these associations are expected to further validate our findings for the potential establishment of personalized prevention of renal disease in the Japanese and East Asian populations.

Parental Socioeconomic Status and Weight Faltering in Infants in Japan.

Background: Previous studies in the UK and Denmark found no significant association between low socioeconomic status (SES) and weight faltering. However, to our knowledge, there are no studies from other developed countries. We examined the association between parental SES and weight faltering in infants up to 1.5 years of age, and investigated whether the inequalities changed between 2001 and 2010 in Japan.Methods: We used data from two Japanese population-based birth cohorts started in 2001 (n = 34,594) and 2010 (n = 21,189). Parental SES was assessed as household income and parental education when the infant was 6 months old. Weight faltering was defined as the slowest weight gaining in 5% of all children in each cohort. Logistic regression analyses were conducted with adjustment for covariates. The relative index of inequality was used to assess relative impact of parental SES on weight faltering.Results: Infants in the lowest quartile of household income were 1.29 (95% confidence interval [CI]: 1.10, 1.52) and 1.27 (95% CI: 1.03, 1.56) times more likely to experience weight faltering than those in the highest income quartile both in the 2001 and 2010 cohorts, respectively. The relative index of inequality for household income was 1.66 (95% CI: 1.36, 1.96) in 2001 and 1.86 (95% CI: 1.42, 2.31) in 2010.Conclusions: Infants from lower income families have a greater risk of weight faltering in Japan. Additionally, the income-related inequalities in weight faltering did not change between the two cohorts. Social policies to address maldistribution of weight faltering due to household income are needed.

Abstract PR15: Projecting individualized absolute risk of developing gastric cancer in Koreans

Abstract Background: Despite the rapid decline of the incidence and mortality over the past few decades, gastric cancer still remains to be the third leading cause of cancer death and the fifth most common cancer worldwide. Furthermore, the absolute number of gastric cancer cases is increasing globally due to the aging of the world population. With available methods to detect and treat precancerous and early stage lesions, development of a prediction model to estimate the probability of developing gastric cancer for various age intervals and risk profiles have important public health implications. Methods: Candidate predictors were selected combining expert opinion and literature search. Using a case-control study with 4,603 Korean subjects, a logistic regression model was used for estimating relative risks, separately for men and women. The discriminatory ability of the models was assessed by receiver operator characteristic area under the curve (AUC). Absolute risk parameters were then calculated combined with the relative risk estimates with baseline age-specific cancer hazard rates from Korean Cancer Registry data. The developed models were validated using an independent prospective cohort data, a Japanese population-based cohort study, which includes 40,173 subjects, by calculating the ratio of expected number (E) over observed number (O) and 95% confidence interval (CI). Results: The models for both men and women included low education, past medical history of diabetes mellitus, no regular use of nonsteroidal inflammatory drugs intake, smoking, no regular exercising, and consumption of high salted food, less fruit, less nonstarchy vegetables, and less nonfermented soy food. The AUC for the relative risk model was 0.73 (95% CI 0.71-0.75) for men and 0.76 (95% CI 0.74-0.79) for women. The overall E/O ratio was 1.05 (95% CI 0.98-1.12) in men, and 0.93 (95% CI 0.83-1.04) in women in the external validation population. Conclusions: To our knowledge this is the first study to estimate the absolute risk of gastric cancer in Korean population. The mathematical models developed in the present study will help predict the occurrence of gastric cancer for an individual considering combined risk factors which will help at a personalized level by enabling early detection and preventive efforts. A further development of a model incorporating biomarkers can provide strategies to select individuals at high risk, for screening for gastric cancer. This abstract is also being presented as Poster B11. Citation Format: Minkyo Song, Jae Jeong Yang, Hyuna Sung, Seong-Ho Kong, Hyuk-Joon Lee, Hyung-Ho Kim, Sang Gyun Kim, Han-Kwang Yang, Norie Sawada, Shoichiro Tsugane, Manami Inoue, Daehee Kang. Projecting individualized absolute risk of developing gastric cancer in Koreans. [abstract]. In: Proceedings of the AACR Special Conference: Improving Cancer Risk Prediction for Prevention and Early Detection; Nov 16-19, 2016; Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(5 Suppl):Abstract nr PR15.