Association between an Antioxidant-Rich Japanese Diet and Chronic Kidney Disease: The Ohasama Study.

AIMS: Although physiological effects of hydrophilic- (H-) and lipophilic- (L-) antioxidant capacities (AOCs) are suggested to differ, the association of an antioxidant-rich diet and chronic kidney disease (CKD) incidence has not been examined. We therefore explored the association between the H- or L-AOC of a whole Japanese diet and CKD risk in a general population. METHODS: A total of 922 individuals without CKD (69.2% women; mean age, 59.5 years old) from Ohasama Town, Japan, were examined. CKD incidence was defined as the presence of proteinuria and/or an estimated glomerular filtration rate (eGFR) of ＜60 ml/min/1.73 m2. Consumption of H-/L-AOC was determined based on the oxygen radical absorbance capacity in a specially developed Japanese food AOC database. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated for new-onset CKD using a Cox proportional hazards model. RESULTS: During the median follow-up of 9.7 years, 137 CKD incidents were recorded. After adjusting for potential confounding variables, the highest quartile of L-AOC was significantly associated with a 51% reduced CKD risk among only women. An increased L-AOC intake was more effective in preventing eGFR reduction than in preventing proteinuria in women. These associations were not seen for H-AOC intake in both sexes and L-AOC intake in men. CONCLUSIONS: A high intake of lipophilic antioxidants may be associated with a reduced CKD risk. The balance between dietary antioxidant intake and pro-oxidants induced by unhealthy lifestyles may be crucial for preventing future kidney deterioration.

Association Between Ambulatory Blood Pressure and Risk of Home Hypertension in a Normotensive Population: The Ohasama Study.

BACKGROUND: We investigated the association between ambulatory blood pressure (BP) and the risk of home hypertension in a normotensive population and whether considering ambulatory BP improves the 10-year prediction model for home hypertension risk, which was developed in the previous Ohasama Study. METHODS: In this prospective study, we followed up with 410 participants (83.2% women; age, 53.6 years) without a home and ambulatory hypertension in the general population of Ohasama, Japan. The Cox model was used to assess the hazard ratios (HRs) for home hypertension (home BP ≥ 135/≥85 mmHg or the initiation of antihypertensive treatment) and model improvement. RESULTS: During a mean 14.2-year follow-up, 225 home hypertension incidences occurred. The HR (95% confidence interval) for home hypertension incidence per 1-SD higher (=6.76 mmHg) 24-hour systolic BP (SBP) was 1.59 (1.33 to 1.90), after adjustments for possible confounding factors, including baseline home SBP. Harrell's C-statistics increased from 0.72 to 0.73 (P = 0.11) when 24-hour SBP was added to the basic 10-year home hypertension prediction model, which includes sex, age, body mass index, smoking status, office SBP, and baseline home SBP. Continuous net reclassification improvement (0.53, P < 0.0001) and integrated discrimination improvement (0.028, P = 0.0014) revealed improvement in the model. CONCLUSIONS: A total of 24-hour SBP could be an independent predictor of future home hypertension. Home BP and 24-hour BP can longitudinally influence each other in the long term.

Female Reproductive Events and Subclinical Atherosclerosis of the Brain and Carotid Arteriopathy: the Ohasama Study.

AIMS: Few studies have investigated the subclinical atherosclerotic changes in the brain and carotid artery, and in East Asian populations. We sought to investigate whether gravidity, delivery, the age at menarche and menopause and estrogen exposure period are associated with subclinical atherosclerosis of the brain and carotid arteriopathy. METHODS: This cross-sectional study formed part of a cohort study of Ohasama residents initiated in 1986. Brain atherosclerosis and carotid arteriopathy were diagnosed as white matter hyperintensity (WMH) and lacunae evident on brain magnetic resonance imaging (MRI) and carotid intimal media thickness (IMT) or plaque revealed by ultrasound, respectively. The effect of the reproductive events on brain atherosclerosis and carotid arteriopathy was investigated using logistic regression and general linear regression models after adjusting for covariates. RESULTS: Among 966 women aged ≥ 55 years in 1998, we identified 622 and 711 women (mean age: 69.2 and 69.7 years, respectively) who underwent either MRI or carotid ultrasound between 1992-2008 or 1993-2018, respectively. The highest quartile of gravidity (≥ 5 vs. 3) and delivery (≥ 4 vs. 2), and the highest and second highest (3 vs. 2) quartiles of delivery were associated with an increased risk of WMH and carotid artery plaque, respectively. Neither of age at menarche, menopause, and estrogen exposure period estimated by subtracting age at menarche from age at menopause was associated with atherosclerotic changes of brain and carotid arteries. CONCLUSIONS: Higher gravidity and delivery are associated with subclinical atherosclerosis of the brain and carotid plaque.

Prediction Models for the 5- and 10-Year Incidence of Home Morning Hypertension: The Ohasama Study.

BACKGROUND: We aimed to develop risk prediction models for new-onset home morning hypertension. METHODS: We followed up 978 participants without home hypertension in the general population of Ohasama, Japan (men: 30.1%, age: 53.3 years). The participants were divided into derivation (n = 489) and validation (n = 489) cohorts by their residential area. The C-statistics and calibration plots were assessed after the 5- or 10-year follow-up. RESULTS: In the derivation cohort, sex, age, body mass index, smoking, office systolic blood pressure (SBP), and home SBP at baseline were selected as significant risk factors for new-onset home hypertension (≥135/85 mm Hg or the initiation of antihypertensive treatment) using the Cox model. In the validation cohort, Harrell's C-statistic for the 5-/10-year home hypertension was 0.7637 (0.7195-0.8100)/0.7308 (0.6932-0.7677), when we used the full model, which included the significant risk factors in the derivation cohort. The calibration test revealed good concordance between the observed and predicted 5-/10-year home hypertension probabilities (P ≥ 0.19); the regression slope of the observed probability on the predicted probability was 1.10/1.02, and the intercept was -0.04/0.06, respectively. A model without home SBP was also developed; for the 10-year home hypertension risk, the calibration test revealed a good concordance (P = 0.19) but Harrell's C-statistic was 0.6689 (0.6266-0.7067). CONCLUSIONS: The full model revealed good ability to predict the 5- and 10-year home morning hypertension risk. Although the model without home SBP is acceptable, the low C-statistic implies that home BP should be measured to predict home morning hypertension precisely.

[Falls and associated risk factors among elderly survivors of the Great East Japan Earthquake: RIAS Study].

Objective　An increasing incidence of disuse syndrome is commonly observed in areas affected by large-scale natural disasters. Consequently, the fall risk is high in such populations, necessitating adequate attention to fall prevention measures. It is important to identify factors associated with falls to prevent deterioration in functional ability. We investigated the risk factors associated with falls among elderly survivors in disaster-stricken areas using longitudinal data from the Research project for the prospective Investigation of health problems Among Survivors of the Great East Japan Earthquake (RIAS) Study.Methods　Of all data obtained from the RIAS Study, we used the data of 1,380 survivors who were aged ≥65 years, were not diagnosed with cancer or cardiovascular disease, did not need supportive care, and could participate in the annual survey between 2011 and 2016. Self-administered questionnaires were distributed, and anthropometric and grip tests were performed during the 2011 survey to obtain information regarding housing damage, the fear of falls, arthralgia, cognitive function psychological distress, insomnia, frequency of leaving the house, a history of hypertension, dyslipidemia, diabetes, alcohol consumption status, smoking status, and/or body mass index, and grip strength. Based on the responses obtained from each annual survey, a fall was defined as an event during which an individual had fallen at least once. Multivariate-adjusted odds ratio(OR) and 95% confidence interval(CI) for all variables related to falls were calculated using logistic regression with adjustment for sex and residential area. Similar analyses were performed based on age groups (65-74 years and ≥75 years).Results　The 5-year fall incidence rate was 35.5% (31.9% [men], 37.9% [women]). In men, cognitive dysfunction was significantly associated with falls (OR 1.50, 95%CI 1.01-2.22). In women, cognitive dysfunction (OR 1.82, 95%CI 1.34-2.47), insomnia (OR 1.41, 95%CI 1.02-1.94), dyslipidemia (OR 1.58, 95% 95% CI 1.11-2.25), and a history of smoking (OR 4.30, 95%CI 1.08-17.14) were significantly associated with falls. In women aged ≥75 years, partial housing damage (OR 7.93, 95%CI 1.85-33.91) and psychological distress (OR 2.83, 95%CI 1.09-.7.37) were also significantly associated with falls.Conclusion　This study suggests that cognitive dysfunction in both sexes and insomnia, dyslipidemia, and a history of smoking in women were significantly associated with falls, and partial housing damage and psychological distress were risk factors for falls in women aged ≥75 years. Fall prevention after large-scale natural disasters warrants close attention to known risk factors and environmental and mental health changes.

The Major Source of Antioxidants Intake From Typical Diet Among Rural Farmers in North-eastern Japan in the 1990s.

BACKGROUND: Previous Japanese studies have led to the erroneous conclusion of antioxidant capacity (AOC) intakes of the overall Japanese diet due to limitations in the number and types of food measured, especially in rice and seafood intake. The aims of the study were to construct an AOC database of foods representative of the typical Japanese diet and to clarify the high contributors to AOC intake from the overall diet of the Japanese population. METHODS: Commonly consumed foods were estimated using 3-day dietary records (DRs) over the four seasons among 55 men and 58 women in Japan. To generate an AOC database suitable for the typical Japanese diet, hydrophilic (H-)/lipophilic (L-) oxygen radical absorbance capacity (ORAC) values of foods in each food group were measured via validated methods using the food intake rankings. Subsequently, we estimated the AOC intake and the AOC characteristics of a typical Japanese diet. RESULTS: Of 989 food items consumed by the participants, 189 food items were measured, which covered 78.8% of the total food intake. The most commonly consumed types of antioxidant-containing food were tea, soybean products, coffee, and rice according to H-ORAC, and soybean products, fish and shellfish, vegetables, and algae according to L-ORAC. CONCLUSIONS: The characteristics of high AOC intake in rice and seafood more appropriately reflected the Japanese-style diet. Further studies are expected to clarify the association between food-derived AOC and its role in preventing or ameliorating lifestyle-related diseases.

Antioxidant Capacities of Plant-Derived Foods Commonly Consumed in Japan.

To provide reliable data for high quality epidemiological studies examining the relationship between health and antioxidant intake from daily foods, 107 plant-derived food items (12 rice, bread and noodles, 5 potatoes and starches, 9 pulses, 6 nuts/seeds, 29 vegetables, 22 fruits, 5 mushrooms, 7 algae, and 12 beverages) were selected as commonly consumed foods in Japan based on dietary records, and their antioxidant capacities were evaluated by validated hydrophilic- and lipophilic-oxygen radical absorbance capacity (H-ORAC and L-ORAC) methods. The food items covered more than 60% of total food intake for each category on a weight basis. The H-ORAC and L-ORAC values were widely distributed at 0-210 and 0-30 µmol-Trolox equivalent/g, respectively. The foods possessing potent antioxidant capacities were found in vegetables and fruits as well as other plant-derived foods. In most foods measured, the H-ORAC values were much larger than the L-ORAC values, except for certain kinds of pulses, nuts/seeds, mushrooms, and algae. The ORAC data shown here is sufficient to accurately estimate the antioxidant intake from plant-derived foods in Japan, and should be useful in future epidemiological studies aiming to clarify the biological significance of ORAC values.

Combined associations of physical activity and dietary intake with health status among survivors of the Great East Japan Earthquake.

BACKGROUND AND OBJECTIVES: Each of the effects of physical activity and dietary intake on health is well known, but combined associations of physical activity and dietary intake on health has not been reported yet. Physical activity and dietary intake are key factors for maintaining health of survivors of the Great East Japan Earthquake in 2011. This study aimed to examine combined associations of physical activity and dietary intake with survivors' health status. METHODS AND STUDY DESIGN: We used data from 6668 participants of a cross-sectional survey taken 3 years (2013) after the disaster. To evaluate combined associations of physical activity and dietary intake, answers to questions regarding these two variables were categorized into four groups: poor physical activity and poor dietary intake (Group 1), poor physical activity and good dietary intake (Group 2), good physical activity and poor dietary intake (Group 3), and good physical activity and good dietary intake (Group 4). Multiple logistic regression analyses were performed by sex, with good self-rated health and good mental health as dependent variables, and age, place of residence, living conditions and physical activity/dietary intake group (with Group 1 as the reference category) as independent variables. RESULTS: Good self-rated health was associated with age in both sexes, and Groups 3 (male: odds ratios (ORs) 1.84 (95% confidence intervals (95% CIs) 1.32-2.57), female: OR 1.82 (95% CI 1.32-2.51)) and 4 (male: OR 1.96 (95% CI 1.39-2.76), female: OR 1.94 (95% CI 1.42-2.64)). Good mental health was associated with Groups 3 (OR 1.48 (95% CI 1.10-1.97)) and 4 (OR 1.86 (95% CI 1.37-1.97)) for male respondents; and living place (other than temporary housing) (OR 1.45 (95% CI 1.26-1.68)) was associated with Group 4 (OR 1.42 (95% CI 1.09-1.85)) for female respondents. CONCLUSIONS: Good physical activity alone or combined with good dietary intake was associated with good self-rated health and good mental health. Further interventions regarding physical activity and dietary intake are needed to improve the health status of survivors.

Different Psychosocial Factors Are Associated With Different Intention and Self-Efficacy Toward Eating Breakfast Among Japanese Breakfast Skippers.

A cross-sectional study was conducted among 7593 adults to clarify lifestyle and psychosocial characteristics of breakfast skippers with different intention and self-efficacy toward eating breakfast. Data were obtained from Japan's national survey in 2009. Multinomial logistic regression analyses were performed to examine the characteristics of each breakfast skipper (having intention and self-efficacy toward eating breakfast [IS], having intention but not self-efficacy [INS], and not having intention to eat breakfast [NI]) compared with breakfast eaters. IS men were less likely to demonstrate understanding of healthy eating. INS and NI men were more likely to eat alone. INS and NI women were less likely to demonstrate understanding of healthy eating. NI men and women were less likely to report weight management behavior. Current smoking and being sleep-deprived were commonly associated with breakfast skipping in both sexes. Our results suggested the need for approaches considering type of breakfast skippers (eg, different intention and self-efficacy).

Personal behaviors including food consumption and mineral supplement use among Japanese adults: a secondary analysis from the National Health and Nutrition Survey, 2003-2010.

BACKGROUND AND OBJECTIVES: A daily mineral supplement is useful for those who are at risk of a deficiency. Some Western reports suggest that mineral supplement users have healthy behaviors and are not mineral-deficient. It is unknown whether the same phenomenon is observed in Japan where there is a different dietary culture. The aim of this study was to examine the characteristics of personal behaviors including food consumption nationwide among mineral supplement users from the National Health and Nutrition Survey in Japan 2003-2010. METHODS AND STUDY DESIGN: Data were obtained from 16,275 adults aged 20-59 years who completed sociodemographic, health status, and 1-day household dietary assessments. Supplement users were compared with non-users. Logistic regression models were utilized to identify the characteristics of food consumption and calcium and iron supplement use, using the medium intake group as a reference. RESULTS: Overall, 2.1% and 1.4% of adults reported using calcium supplements and iron supplements, respectively. Calcium supplement users were more likely to be physically active, non-smokers, and eat less fat compared with non-users. Furthermore, they were more likely than non-users to consume a higher intake of calcium from foods such as tea, vegetables, seaweeds, and fruits. Iron supplement users were more likely than non-users to be non-smokers. These individuals tended to have a high intake of seaweeds and fruits. CONCLUSIONS: Japanese adults who had healthier behaviors were more likely to use mineral supplements, especially calcium. Mineral supplement users tended to choose healthy foods such as seaweeds and fruits, without considering their overall mineral consumption.

Animal protein intake is associated with higher-level functional capacity in elderly adults: the Ohasama study.

OBJECTIVES: To determine the association between protein intake and risk of higher-level functional decline in older community-dwelling adults. DESIGN: Prospective. SETTING: Ohasama Town, Japan. PARTICIPANTS: Residents (N = 1,007; mean age 67.4 ± 5.5) free of functional decline at baseline; follow-up was conducted for 7 years. MEASUREMENTS: Nutrient and food intakes were determined using a validated 141-item food frequency questionnaire. Participants were divided into quartiles according to intake levels of total, animal, and plant protein. Subscales of the Tokyo Metropolitan Institute of Gerontology Index of Competence subscales were used to assess higher-level functional decline. Logistic regression analysis was used to examine the future risk of higher-level functional decline in relation to protein intake, with lowest protein intake as reference. RESULTS: During the study period, 24.4% of eligible participants reported declines in higher-level functional capacity. After adjustment for putative confounding factors, men in the highest quartile of animal protein intake had significantly lower risk of higher-level functional decline than those in the lowest quartile (odds ratio (OR) = 0.41, 95% confidence interval (CI) = 0.20-0.83; P for trend .01). These associations were not seen in women (OR = 0.76, 95% CI = 0.41-1.34; P for trend .37). No consistent association was observed between plant protein intake and future higher-level functional decline in either sex. CONCLUSION: Higher protein, particularly animal protein, was associated with lower risk of decline in higher-level functional capacity in older men. Animal protein intake may be a modifiable indicator for early detection and prevention of higher-level functional decline in elderly adults.

Food intake and the risk of endometrial endometrioid adenocarcinoma in Japanese women.

The present study examined the association between food intake and endometrial cancer restricted to endometrial endometrioid adenocarcinoma (EEA) using a case-control study in Japanese women. One hundred sixty-one cases and 380 controls who completed a questionnaire regarding demographic, lifestyle, and food frequency questionnaire were analyzed. Odds ratio (OR) between selected food intakes and EEA were calculated by logistic regression analysis. After adjustment putative confounding factors, the higher intakes of vegetables [odds ratio (OR) = 0.47, 95% confidence interval (CI) = 0.26-0.83], peanuts (OR = 0.48, CI = 0.27-0.86), fish (OR = 0.52, CI = 0.29-0.93), boiled egg (OR = 0.24, CI = 0.33-0.92), instant noodles (OR = 1.94, CI = 1.12-3.34), instant food items (OR = 2.21, CI = 1.31-3.74), and deep-fried foods (OR = 2.87, CI = 1.58-5.21) were associated with a risk for EEA. The inverse association with a risk of EEA was also seen in higher intakes (g/1000 kcal) for vegetables (0.45, CI = 0.25-0.81) and fish (0.53, CI = 0.30-0.94) as compare to lower intake. Higher intake of vegetables, peanuts, fish, and boiled egg was associated with a reduced risk for EEA, whereas instant noodles, instant food items, and deep-fried foods was associated with an increased risk for EAA as compared to lower levels of intake.

Health behaviors as predictors for declines in higher-level functional capacity in older adults: the Ohasama study.

OBJECTIVES: To determine the characteristics of health behaviors related to higher-level functional decline in older community-dwelling adults. DESIGN: Prospective. SETTING: Ohasama Town, Japan. PARTICIPANTS: One thousand fifty residents (mean age: 67.5) free of functional decline at baseline. MEASUREMENTS: Health behaviors including smoking status, alcohol consumption, frequency of exercise, sleep duration, dietary habits (supplement use, breakfast, late-night snacking, eating regularly, and eating out), and self-rated health were obtained from a self-administered questionnaire at baseline. Higher-level functional decline was examined using the subscales of the Tokyo Metropolitan Institute of Gerontology Index of Competence. RESULTS: During the 7-year follow-up, 27.5% of eligible participants reported decline in higher-level functional capacity. After adjustment for putative confounding factors, health behaviors that were significant predictors for declines in higher-level functional capacity at the 7-year follow-up were current smoking (odds ratio (OR) = 1.58, 95% confidence interval (CI) = 1.06-2.36), sleep duration of 9 hours or longer (OR = 2.15, 95% CI = 1.49-3.11), and poor self-rated health (OR = 1.93, 95% CI = 1.40-2.67). CONCLUSION: Several modifiable health behaviors contribute to higher-level functional decline.

Estimated average daily intake of antioxidants from typical vegetables consumed in Japan: a preliminary study.

The hydrophilic antioxidant content of 23 vegetables commonly consumed in Japan was assessed by the hydrophilic oxygen radical absorbance capacity (H-ORAC) method to estimate the dietary intake of total antioxidants in Japan. The estimated average H-ORAC value for "typical vegetables" consumed in Japan was 594.3 µmol Trolox equivalent (TE)/100 g. Hence, 2080 µmol TE/d of hydrophilic antioxidants would be ingested when 350 g of vegetables a day are consumed.

Association of environmental tobacco smoke exposure with elevated home blood pressure in Japanese women: the Ohasama study.

OBJECTIVE: Only a few of numerous epidemiological studies have demonstrated a positive association between environmental tobacco smoke (ETS) exposure and blood pressure (BP), despite experimental studies showing such a positive association. The association between home blood pressure (HBP) and ETS exposure was investigated in the general population. METHODS: Five hundred and seventy-nine nonsmoking Japanese women were enrolled. The participants were classified into four categories according to their responses to a self-administered questionnaire: unexposed women (non-ETS), women exposed at home [ETS(home)], at the workplace/other places [ETS(work/other)] and at home and at the workplace/other places [ETS(both)]. Variables were compared using analysis of covariance adjusted for age, marital status, body mass index, diabetes mellitus, stroke, heart disease, hyperlipidemia, alcohol intake, salt intake and activity levels. RESULTS: In participants without antihypertensive medication, systolic morning HBP in ETS(both) was 4 mmHg higher than that in non-ETS (116.8 +/- 1.01 vs. 113.1 +/- 1.08 mmHg, P = 0.02) and systolic morning HBP in ETS(home) and systolic evening HBP in ETS(both) were 3 mmHg higher than those in non-ETS (116.2 +/- 1.07 vs. 113.1 +/- 1.08 mmHg, P = 0.04; and 115.3 +/- 1.02 vs. 111.9 +/- 1.09 mmHg, P = 0.03, respectively). In participants with antihypertensive medication, ETS exposure status was not significantly associated with increased HBP levels. CONCLUSIONS: A positive association between HBP levels and ETS exposure was confirmed. HBP measurement is recommended in population-based studies investigating the effects of ETS exposure. ETS exposure may increase BP, thereby synergistically contributing to unfavorable cardiovascular outcomes along with other deleterious effects of ETS.