Dietary behaviours and related lifestyles according to the presence or absence of skipping breakfast in Japanese adults: the JPHC-NEXT study.

OBJECTIVE: To assess dietary behaviours and related lifestyles according to the presence or absence of skipping breakfast. DESIGN: We analysed the cross-sectional data from a baseline survey of a large-scale population-based cohort study in Japan conducted in 2011-2016. Participants provided information on dietary behaviours and lifestyles through a self-administered questionnaire. Skipping breakfast was defined as not eating breakfast at least once a week and was classified according to the frequency of skipping breakfast as 1-2, 3-4 or ≥5 times/week. SETTING: Sixteen municipalities in seven prefectural areas across Japan under the Japan Public Health Centre-based prospective study for the Next Generation. PARTICIPANTS: 112 785 residents (51 952 males and 60 833 females) aged 40-74 years. RESULTS: After adjustment for age, socio-demographic status, drinking status and smoking status, individuals who skipped breakfast at least once a week, compared with those who ate breakfast every day, were more likely to have adverse dietary behaviours such as frequent eating out (multivariable OR = 2·08, 95 % CI (1·96, 2·21) in males and 2·15, 95 % CI (1·99, 2·33) in females), frequent eating instant foods (1·89, 95 % CI (1·77, 2·01) in males and 1·72, 95 % CI (1·56, 1·89) in females). They had late bedtime (1·85, 95 % CI (1·75, 1·95) in males and 1·98, 95 % CI (1·86, 2·11) in females) and living alone (2·37, 95 % CI (2·17, 2·58) in males and 2·02, 95 % CI (1·83, 2·21) in females), using the logistic regression model. CONCLUSIONS: Both adult males and females who skipped breakfast were likely to eat out, to have a dietary habit of eating instant foods and have lifestyles such as late bedtime and living alone than those who ate breakfast.

Long-term Response of Helicobacter pylori Antibody Titer After Eradication Treatment in Middle-aged Japanese: JPHC-NEXT Study.

BACKGROUND: Helicobacter pylori (H. pylori) is an established causative factor of gastric cancer. Although the expansion of insurance coverage has led to an increase in the number of patients treated for H. pylori, the population impact of eradication treatment for H. pylori has been scarcely investigated. This study aimed to clarify the long-term responses of H. pylori antibody titer after eradication treatment using large scale cross-sectional data from the Japan Public Health Center-based Prospective Study for the Next Generation (JPHC-NEXT Study). METHODS: A total of 55,282 Japanese participants aged 40 to 74 years residing in 16 areas provided blood samples from 2011 through 2016. From these, treated (n = 6,276) and untreated subjects who were seropositive for H. pylori or had serological atrophy (n = 22,420) formed the study population (n = 28,696). Seropositivity was defined as an anti-H. pylori IgG titer of ≥10 U/mL. Antibody level was compared among subjects according to self-reported treatment history as untreated, and treated for less than 1 year (<1Y), 1 through 5 years (1-5Y), and 6 or more years ago (6Y+). RESULTS: Median serum antibody titer was 34.0 U/mL, 7.9 U/mL, 4.0 U/mL, and 2.9 U/mL for the untreated, <1Y, 1-5Y, and 6Y+ groups, respectively. While those treated for H. pylori within the previous year had a 76.8% lower antibody titer compared to untreated subjects, approximately 41% of subjects were still seropositive. CONCLUSION: A significant reduction in H. pylori antibody titer occurs within 1 year after eradication treatment, but that a long period is needed to achieve complete negative conversion.

Role of insulin resistance in the association between resting heart rate and type 2 diabetes: A prospective study.

BACKGROUND: Elevated resting heart rate (RHR) is a predictor of incident type 2 diabetes (T2D). Insulin resistance is thought to play a role in this association; however, the extent to which insulin resistance mediates this association is unclear. METHODS: 1309 Japanese individuals without diabetes were recruited during 2009-2012 and followed for 5 years, of whom 78 developed T2D, as diagnosed by the 75 g oral glucose tolerance test. Supine RHR was measured by electrocardiography. Using logistic regression analysis, we examined the association between RHR and incident T2D, and interaction with the homeostasis model assessment of insulin resistance (HOMA-IR) index. Causal mediation analysis was applied to decompose the effect of RHR on the outcome and estimate the proportion mediated by the HOMA-IR index. RESULTS: The sex- and age-adjusted cumulative incidence rate of T2D increased with increasing RHR. After adjustment for sex, age, waist circumference, current smoking status, alcohol use, habitual exercise, and cardiovascular disease medications, individuals with a RHR ≥80 bpm, compared with <60 bpm, showed an increased risk of incident T2D [odds ratio (OR), 2.89; 95 % confidence interval (CI), 1.07 to 7.80]. Multivariate adjusted OR for the total effect per 1 SD increase in RHR on incident T2D was 1.37 (95 % CI, 1.01 to 1.74) in the mediation analysis, and the proportion of the total indirect effect mediated by the HOMA-IR index was 27.5 % (95 % CI, 1.5 to 53.5). CONCLUSIONS: Approximately 30 % of the effect of RHR on incident T2D was explained by the indirect effect of insulin resistance.

Relation Between Body Mass Index and Dry Eye Disease: The Japan Public Health Center-Based Prospective Study for the Next Generation.

OBJECTIVE: To investigate the relation between body mass index (BMI) and dry eye disease (DED). METHODS: We conducted a cross-sectional questionnaire-based survey in 85,264 Japanese men and women aged 40 to 74 years who participated in the Japan Public Health Center-based Prospective Study for the Next Generation (JPHC-NEXT Study). Dry eye disease was defined as the presence of severe symptoms or clinical diagnosis. A multivariable logistic regression model was used to estimate the odds ratios (ORs) of DED associated with BMI and their two-sided 95% confidence intervals (CIs). We adjusted for age, cohort area, visual display terminal time, smoking status, alcohol intake, education status, income status, as well as history of hormone replacement therapy for women. RESULTS: Prevalence of DED was 23.4% (n = 19,985; 6,289 men, 13,696 women). Higher BMI was correlated with a lower prevalence of DED in a dose-response fashion, with an adjusted OR of DED (95% CI) per 1 kg/m2 increment of BMI of 0.98 (95% CI: 0.97-0.99) for men and 0.97 (95% CI: 0.97-0.98) for women. CONCLUSIONS: This large population-based study showed an inverse relationship between BMI and prevalence of DED in a Japanese population. Underestimation of DED is warned, especially for participants with high BMI.

Working cancer survivors' physical and mental characteristics compared to cancer-free workers in Japan: a nationwide general population-based study.

PURPOSE: This study compared working cancer survivors' self-rated health status (SRHS), physical functional capacity, depressive symptoms, and happiness to those of cancer-free workers. METHODS: A nationwide general population-based cross-sectional study on a sample of Japanese was conducted. Prevalence of deteriorated SRHS, restricted physical functional capacity, depressive symptoms, and perceived happiness were compared between working cancer survivors and cancer-free workers with multivariable logistic regression analysis adjusted for age and sociodemographic and health-related backgrounds. RESULTS: Of the 28,311 male and 26,068 female workers, 977 (3.5%) and 1267 (4.9%) were cancer survivors, respectively. Working cancer survivors reported deteriorated SRHS more frequently than cancer-free workers: 21.3% vs. 13.8%, multivariable-adjusted odds ratio (95% confidence interval), 1.64 (1.39-1.95) for men, 23.8% vs. 17.5%, 1.34 (1.16-1.54) for women. Restricted physical functional capacity was reported more frequently in working cancer survivors than cancer-free workers: 6.8% vs. 2.6%, 1.76 (1.34-2.32) for men, 4.9% vs. 2.0%, 2.06 (1.56-2.71) for women. No significant difference was found for depressive symptoms: 21.6% vs. 22.9% in men, 30.0% vs. 28.5% in women. Working cancer survivors felt happiness more frequently than cancer-free survivors in men (77.3% vs. 71.7%, 1.21 (1.01-1.45)) but not in women (76.1% vs. 74.9%). CONCLUSIONS: Working cancer survivors had worse SRHS and more restricted physical functional capacity than cancer-free workers. In men, working cancer survivors felt happiness more frequently than cancer-free workers. IMPLICATIONS FOR CANCER SURVIVORS: Continuous support to improve cancer survivors' SRHS and physical functional capacity would be necessary even while they are working.

The Japan Public Health Center-based Prospective Study for the Next Generation (JPHC-NEXT): Study Design and Participants.

BACKGROUND: Lifestyle and life-environment factors have undergone drastic changes in Japan over the last few decades. Further, many molecular epidemiologic studies have reported that genetic, epigenetic, and other biomarker information may be useful in predicting individual disease risk. METHODS: The Japan Public Health Center-based Prospective Study for the Next Generation (JPHC-NEXT) was launched in 2011 to identify risk factors for lifestyle-related disease, elucidate factors that extend healthy life expectancy, and contribute toward personalized healthcare based on our more than 20 years' experience with the JPHC Study. From 2011 through 2016, a baseline survey was conducted at 16 municipalities in seven prefectures across the country. A self-administered questionnaire was distributed to all registered residents aged 40-74, which mainly asked about lifestyle factors, such as socio-demographic situation, personal medical history, smoking, alcohol and dietary habits. We obtained informed consent from each participant to participate in this long follow-up study of at least 20 years, including consent to the potential use of their residence registry, medical records, medical fee receipts, care insurance etc., and to the provision of biospecimens (blood and urine), including genomic analysis. RESULTS: As of December 31, 2016, we have established a population-based cohort of 115,385 persons (Response rate 44.1%), among whom 55,278 (47.9% of participants) have provided blood and urine samples. The participation rate was slightly higher among females and in the older age group. CONCLUSION: We have established a large-scale population-based cohort for next-generation epidemiological study in Japan.

Association Between Heart Rate Variability and Home Blood Pressure: The Toon Health Study.

BACKGROUND: Although blood pressure (BP) is regulated by the autonomic nervous system, it is not fully understood how autonomic activity affects BP at home in the general population. METHODS: Subjects were enrolled from 2009 to 2012 and included 1,888 men and women aged 30-79 years. We measured casual BP in the morning during health checkups and asked participants to monitor BP at home twice in the morning and evening for 1 week. The mean of the two measurements of mean arterial pressure (MAP) was calculated. Five-minute recordings of the pulse wave from a fingertip sensor were used to determine the following indices of heart rate variability (HRV): standard deviation of normal-to-normal RR intervals (SDNN), root mean square of successive differences in RR intervals (RMSSD), high frequency (HF) power, low frequency (LF) power, and LF/HF. RESULTS: Sex- and age-adjusted means of casual MAP, and morning and evening MAP at home were significantly different among quartiles of SDNN, RMSSD, and HF. When further adjusted for smoking, alcohol drinking, medication for hypertension, diabetes, sleeping hours, snoring, and mental health status, the associations were somewhat attenuated. Inverse relationships were found between the means of morning home MAP, and RMSSD (P = 0.02) and HF (P = 0.051) after adjustment for confounders. The association between MAP and RMSSD, or MAP and HF was evident in individuals <65 years old. CONCLUSION: Low HF and RMSSD, which reflect impaired parasympathetic nervous system activity, were associated with increased home MAP in the morning rather than in the evening.

Skipping Breakfast is Correlated with Obesity.

OBJECTIVE: Despite the fact that the total energy intake of Japanese people has decreased, the percentage of obese people has increased. This suggests that the timing of meals is related to obesity. The purpose of the study was to investigate the relationship between the timing of meals and obesity, based on analyses of physical measurements, serum biochemical markers, nutrient intake, and lifestyle factors in the context of Chrononutrition. PARTICIPANTS AND METHODS: We analyzed data derived from 766 residents of Toon City (286 males and 480 females) aged 30 to 79 years who underwent detailed medical examinations between 2011 and 2013. These medical examinations included. (1) physical measurements (waist circumference, blood pressure, etc.); (2) serum biochemical markers (total cholesterol, etc.); (3) a detailed questionnaire concerning lifestyle factors such as family structure and daily habits (22 issues), exercise and eating habits (28 issues), alcohol intake and smoking habits; (4) a food frequency questionnaire based on food groups (FFQg); and (5) a questionnaire concerning the times at which meals and snacks are consumed. RESULTS: The values for body mass index (BMI) and waist circumference were higher for participants who ate dinner less than three hours before bedtime (<3-h group) than those who ate more than three hours before bedtime (>3-h group). The Chi-square test showed that there was a significant difference in eating habits, e.g., eating snacks, eating snacks at night, having dinner after 8 p.m., and having dinner after 9 p.m., between the <3-h group and the >3-h group. Multiple linear regression analysis showed that skipping breakfast significantly influenced both waist circumference (ß = 5.271) and BMI (ß = 1.440) and that eating dinner <3-h before going to bed only influenced BMI (ß = 0.581). CONCLUSION: Skipping breakfast had a greater influence on both waist circumference and BMI than eating dinner <3-h before going to bed.