Determinants of double product: a cross-sectional study of urban residents in Japan.

BACKGROUND: The current study aimed to investigate the determinants of high double product (DP) by evaluating the association between resting DP, which is calculated as systolic blood pressure (SBP) multiplied by heart rate (HR), and blood test results and lifestyle factors. METHODS: This research included 973 participants in the baseline survey of the KOBE study, which included a cohort of urban residents. The possible DP determinants were identified by examining the association between lifestyle factors and laboratory findings and DP by analyzing covariance adjusted for sex and age. Logistic regression analysis was performed with high DP (SBP × HR ≥ 9145 mmHg beats/min or quintile according to sex) as outcome and DP determinants as independent variables. RESULTS: Age, hematocrit, and gamma-glutamyl transferase (log) level were positively associated with a high DP in both men and women. In addition, a high DP was positively associated with Homeostatic Model Assessment for Insulin Resistance score in women alone. Meanwhile, the amount of exercise was negatively associated with a high DP in men alone. CONCLUSIONS: High DP values at rest were associated with insulin resistance, gamma-glutamyl transferase, and the amount of exercise in participants without underlying disease.

Regular dental visits, periodontitis, tooth loss, and atherosclerosis: The Ohasama study.

OBJECTIVE: We aimed to explore the association between regular dental visits and atherosclerosis and between periodontitis, number of remaining teeth, and atherosclerosis among community dwellers in Japan. BACKGROUND: Few studies have examined the association between regular dental visits, periodontitis, tooth loss, and atherosclerosis in community dwellers in Japan. METHODS: The participants of this cross-sectional study included community dwellers aged ≥55 years and residing in Ohasama. Exposure variables were regular dental visits; periodontitis, defined as radiographic alveolar bone loss (BL); the Centers for Disease Control/American Academy of Periodontology (CDC/AAP) classification; and number of remaining teeth. The primary outcome was atherosclerosis, defined as maximum carotid intima-media thickness ≥1.1 mm or confirmation of atheromatous plaque. RESULTS: Of 602 participants, 117 had atherosclerosis. In the multivariate model, compared to those with regular dental visits, the odds ratio (OR) (95% confidence intervals [CIs]) of atherosclerosis among those with the absence of regular dental visits was 2.16 (1.03-4.49). Regarding BL-max, compared with those in the first quartile, ORs (95% CIs) of those in the second, third, and fourth quartiles were 1.15 (0.65-2.30), 0.65 (0.32-1.35), and 1.57 (0.81-3.01), respectively. Regarding CDC/AAP classification, compared to those with no or mild periodontitis, ORs (95% CIs) for those with moderate and severe periodontitis were 2.48 (0.61-10.1) and 4.26 (1.01-17.5), respectively. Regarding the number of remaining teeth, compared to those with ≥20 teeth, ORs (95%CIs) for those with 10-19 and 1-9 teeth were 1.77 (1.004-3.12) and 0.96 (0.52-1.80), respectively. CONCLUSION: The absence of regular dental visits and presence of periodontitis are associated with atherosclerosis among community dwellers in Japan.

Higher serum uric acid level is inversely associated with renal function assessed by cystatin C in a Japanese general population without chronic kidney disease: the KOBE study.

BACKGROUND: Although several epidemiological studies have suggested that high serum uric acid (SUA) levels are related to a decline in kidney function, only a few studies have investigated using cystatin C to calculate estimated glomerular filtration rate (eGFR). We aimed to clarify the relationship between SUA levels and kidney function assessed by cystatin C in a Japanese general community population without chronic kidney disease (CKD). METHODS: We conducted a community-based cross-sectional study that included 1086 healthy participants, aged 40-74 years, without CKD and not undergoing treatment of hyperuricemia, who had participated in the baseline survey of the Kobe Orthopedic and Biomedical Epidemiological (KOBE) study. The preconditions for participation in this study were no past histories of cardiovascular disease or cancer, and not undergoing treatment for diabetes, hypertension, or dyslipidemia. We classified the participants into quartiles stratified by sex according to their SUA level and then examined the relationship with eGFR. The odds ratios for having a low eGFR, defined as the lowest quartile of eGFR (i.e., ≤78.4 mL/min/1. 73m2) was estimated according to SUA quartiles (men, Q1 ≤ 5.0, Q2 5.1-5.9, Q3 6.0-6.6, and Q4 ≥ 6.7; women, Q1 ≤ 3.8, Q2 3.9-4.3, Q3 4.4-4.9, and Q4 ≥ 5.0 mg/dL) after adjustment for age, body mass index, systolic blood pressure, HbA1c, high and low density lipoprotein cholesterol, and smoking and drinking habits. The adjusted mean of each quartile was also calculated. RESULTS: Multivariable-adjusted means of eGFR showed a graded decrease in higher SUA quartiles (men, Q1 90.5, Q2 88.0, Q3 83.5, and Q4 82.0; women, Q1 95.7, Q2 91.3, Q3 89.2, and Q4 86.7). In addition, the multivariable-adjusted odds ratios for having a lower eGFR (95% confidence interval) for each SUA quartile compared with Q1 was Q2 2.29 (0.98, 5.35), Q3 4.94 (2.04, 11.97), and Q4 8.01 (3.20, 20.04) for men, and was Q2 2.20 (1.12, 4.32), Q3 2.68 (1.39, 5.20), and Q4 4.96 (2.62, 9.41) for women. CONCLUSIONS: There was a graded inverse relationship between mild elevations in SUA levels and eGFR assessed by cystatin C in an apparently healthy Japanese population without CKD. This association was similar in both men and women.

Underweight Young Women Without Later Weight Gain Are at High Risk for Osteopenia After Midlife: The KOBE Study.

BACKGROUND: Although underweight young women are targets for interventions to prevent low bone mineral density (BMD), the relationship between change in body mass index (BMI) from youth to older age and BMD has not been widely investigated in community dwellers. METHODS: In 749 healthy Japanese women aged 40-74 years, BMD was measured by quantitative ultrasound and anthropometric measurements, and BMI was calculated from body weight and height. The BMI of participants at age 20 years was estimated by self-reported body weight and their present height. They were classified into four groups according to the presence of underweight (BMI <18.5 kg/m2) at 20 and/or at present. Logistic regression models were used to estimate multivariate-adjusted odds ratios (ORs) of the presence of underweight at 20 and/or at present for osteopenia (BMD T score <-1 standard deviations) compared with participants with BMI ≥18.5 kg/m2 both at 20 and at present. RESULTS: The participants who were underweight both at 20 and at present had a higher OR for osteopenia compared with those with BMI ≥18.5 kg/m2 at 20 and at present (OR 3.94; 95% confidence interval [CI], 1.97-7.89). Those underweight only at present also had significantly increased OR of developing osteopenia (OR 2.95; 95% CI, 1.67-5.24). The OR of those underweight only at 20 was 0.87 (95% CI, 0.51-1.48). CONCLUSIONS: Current underweight was associated with increased risk for osteopenia among Japanese women, especially in those who were underweight both at 20 and at present. To prevent low BMD in the future, maintaining appropriate body weight might be effective for young underweight women.

Impact of Flushing Response on the Relationship between Alcohol Consumption and Gamma-glutamyl Transpeptidase: the KOBE study.

Individuals with an inactive acetaldehyde dehydrogenase 2 have an. elevated level of serum acetaldehyde after drinking alcohol, and this may cause an alcohol flushing response with symptoms such as facial flushing, tachycardia, headache, and nausea. Recent studies have suggested that the flushing response influences the association between alcohol consumption and various health-related outcomes. In the present study, we investigated the impact of the flushing response on the relationship between alcohol consumption and serum y -GTP levels in Japanese drinkers. We conducted a cross-sectional study of 521 Japanese drinkers (260 men and 261 'vomen) to examine the impact of the alcohol flushing response on the relationship between alcohol consumption and serum y -GTP levels. The subjects were divided into three groups according to the amount .of daily alcohol consumption. (low, <20 g; moderate, 20-39 g;. and high, >40 g). Multiple adjustments were performed with linear regression models to examine the association between daily alcohol consumption and serum y-GTP levels, adjusting for potential con- founders including the flushing response. We found that the proportion of flushers was significantly lower in the high alcohol consumption group than in the low consumption group. The results of a multivariable analysis showed that,serum y -GTP levels were significantly higher in the moderate and high consumption groups than in the low consumption group after. adjusting for all potential confounders other than the flushing response. In addition, the association between serum y -GTP levels and alcohol consumption was unchanged after adjusting for the presence of the flushing response. In conclusion, serum y -GTP levels increased with increasing alcohol-consumption regardless of the flushing response. Screening for heavy drinkers using serum y-GTP levels was very important to prevent alcohol-related diseases or health problems in health examination.

Changes in Waist Circumference and the Incidence of Type 2 Diabetes in Community-Dwelling Men and Women: The Suita Study.

BACKGROUNDS: The association between weight gain and the incidence of type 2 diabetes is well known. The aim of our study was to investigate the relationship between change in waist circumference (WC) and type 2 diabetes incidence. METHODS: The participants in the Suita Study, a population-based cohort study in an urban area of Japan, underwent a baseline survey between 1989 and 1994 (Exam 1) and were examined at follow-up every 2 years. We performed a 9.3-year cohort study of 946 men and 1327 women with no history of diabetes who underwent Exam 1 and Exam 2 (between 1997 and 1999). Participants were stratified by sex and median WC at Exam 1, and, in each stratum, participants were further classified into three categories by tertile of WC change per year between Exam 1 and Exam 2. Hazard ratios (HRs) and 95% confidence intervals (CIs) for type 2 diabetes incidence were calculated by Cox proportional hazard models. The endpoints were first diagnosis of type 2 diabetes or March 2011. RESULTS: During follow-up, 287 participants developed type 2 diabetes. In both sexes with median WC or higher, participants in the highest tertile of WC change had a significantly higher risk of developing type 2 diabetes. Multivariable adjusted HRs were 1.84 (95% CI, 1.10-3.08) in men and 2.30 (95% CI, 1.31-4.04) in women. No significant association was observed among participants with WC below median. CONCLUSIONS: Preventing WC gain is important in preventing type 2 diabetes in the Japanese population, especially among individuals with a relatively high WC.

Daytime physical activity and sleep in pre-schoolers with developmental disorders.

AIM: This study aims to investigate the association between daytime physical activity (PA) and sleep in pre-schoolers with or without autism spectrum disorders (ASDs). METHOD: Thirty-one pre-school children with ASD and 16 age-matched controls were recruited. Sleep and PA patterns were measured with an Actiwatch for 7 days. After average PA values were calculated for three periods (morning, afternoon and evening) of each day for each child, the days with maximum (active) and minimum (inactive) PA values for these three periods were determined. The Wilcoxon signed-rank test was used to compare sleep following active mornings, afternoons and evenings with that following inactive time periods. RESULTS: In control children, sleep onset time following active mornings/afternoons did not differ from that following inactive mornings/afternoons. In contrast, sleep onset following the most inactive morning (median sleep onset time: 9:57 pm) and the most inactive afternoon (median sleep onset time: 10:24 pm) began significantly later than that following the most active mornings (median sleep onset time: 9:21 pm) and the most active afternoons (median sleep onset time: 9:39 pm) in children with ASD. The percentage of sleep for control children following active mornings was significantly higher (median: 93.2%) than that following inactive ones (median: 91.7%). Significant associations were not found between evening PA and sleep in either ASD or control children. CONCLUSIONS: A high level of morning and afternoon PA can advance the sleep phase in children with ASD.

Characteristics and Risk of Diabetes in People With Rare Glucose Response Curve During an Oral Glucose Tolerance Test.

CONTEXT: Existing differences in persons with lower 30- or 60-minute plasma glucose (PG) levels during 75-g oral glucose tolerance test (OGTT) than fasting PG remain unclear. OBJECTIVE: To clarify the characteristics of persons whose PG levels decrease after glucose administration during OGTT and their risk of incidence of diabetes in a Japanese general population. METHODS: In this cohort study, a total of 3995 men and 3500 women (mean age 56.7 years) without diabetes were classified into 3 groups: (1) PG at both 30 and 60 minutes ≥ fasting PG; (2) PG at 30 minutes ≥ fasting PG and PG at 60 minutes < fasting PG; (3) PG at 30 minutes < fasting PG. The characteristics and the risk of diabetes onset were analyzed using ordered logistic regression and Cox proportional hazard regression, respectively. RESULTS: Among 7495 participants, the numbers of individuals in the group 1, 2, and 3 were 6552, 769, and 174, respectively. The glucose response curve of the group 3 was boat shaped. Group 3 had the youngest age, lowest percentage of men, and best health condition, followed by groups 2 and 1. Among 3897 participants analyzed prospectively, 434 developed diabetes during the mean follow-up period of 5.8 years. The hazard ratio for diabetes onset in the group 2 was 0.30 with reference to the group 1. No-one in group 3 developed diabetes. CONCLUSION: People with lower 30-minute PG than fasting PG tended to be women, young, healthy, and at low risk of diabetes onset.

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.

Impact of impaired insulin secretion and insulin resistance on the incidence of type 2 diabetes mellitus in a Japanese population: the Saku study.

AIMS/HYPOTHESIS: To assess the impact of impaired insulin secretion (IIS) and insulin resistance (IR) on type 2 diabetes incidence in a Japanese population. METHODS: This 4 year cohort study included 3,059 participants aged 30-69 without diabetes at baseline who underwent comprehensive medical check-ups between April 2006 and March 2007 at Saku Central Hospital. Based on their insulinogenic index and HOMA-IR values, participants were classified by the criteria of the Japan Diabetes Society into four categories: normal; isolated IIS (i-IIS); isolated IR (i-IR); and IIS plus IR. They were followed up until March 2011. The incidence of type 2 diabetes was determined from fasting and 2 h post-load plasma glucose concentrations and from receiving medical treatment for diabetes. RESULTS: At baseline, 1,550 individuals (50.7%) were classified as normal, 900 (29.4%) i-IIS, 505 (16.5%) i-IR, and 104 (3.4%) IIS plus IR. During 10,553 person-years of follow-up, 219 individuals developed type 2 diabetes, with 126 (57.5%) having i-IIS at baseline. Relative to the normal group, the multivariable-adjusted HRs for type 2 diabetes in the i-IIS, i-IR and IIS plus IR groups were 8.27 (95% CI 5.33, 12.83), 4.90 (95% CI 2.94, 8.17) and 16.93 (95% CI 9.80, 29.25), respectively. The population-attributable fractions of type 2 diabetes onset due to i-IIS, i-IR, and IIS plus IR were 50.6% (95% CI 46.7%, 53.0%), 14.2% (95% CI 11.8%, 15.6%) and 12.9% (95% CI 12.3%, 13.2%), respectively. CONCLUSIONS/INTERPRETATION: Compared with IR, IIS had a greater impact on the incidence of type 2 diabetes in a Japanese population.

Effect of age on the association between waist-to-height ratio and incidence of cardiovascular disease: the Suita study.

BACKGROUND: Waist-to-height ratio (WHtR) has been shown to be a useful screening tool for metabolic syndrome and cardiovascular disease (CVD). We investigated the association of WHtR with CVD incidence by age group. METHODS: We conducted a 13.0-year cohort study of Japanese adults (2600 men and 2888 women) with no history of CVD. WHtR was calculated as waist circumference (cm) (WC) divided by height (cm). We stratified participants by sex and age group (30-49, 50-69, ≥70 years). Using the Cox proportional hazards model, we calculated hazard ratios (HRs) and 95% CIs for CVD in relation to WHtR quartile for participants aged 50 to 69 years and 70 years or older. RESULTS: Men aged 50 to 69 years in the highest quartile had significantly increased risks of CVD and coronary heart disease as compared with the lowest quartile; the HRs (95% CI) were 1.82 (1.13-2.92) and 2.42 (1.15-5.12), respectively. Women aged 50 to 69 years in the highest quartile had a significantly increased risk of stroke (HR, 2.43; 95% CI, 1.01-5.85). No significant results were observed in men or women aged 70 years or older. The likelihood ratio test showed that the predictive value of WHtR was greater than that of WC among men aged 50 to 69 years. CONCLUSIONS: The association between WHtR and CVD risk differed among age groups. WHtR was useful in identifying middle-aged Japanese at higher risk of CVD and was a better predictor than WC of CVD, especially in men.

Lifestyle and the risk of diabetes mellitus in a Japanese population.

The objective was to examine the association between lifestyle and risk for diabetes. For an average of 9.9 years, this study prospectively followed a cohort of 7,211 (2,524 men and 4,687 women) community residents aged 30-69 years without diabetes at a health check-up conducted between April 1990 and March 1992 until diabetes was confirmed or until the end of 2006. The subjects were divided into 6 groups according to their total scores of Breslow's lifestyle index (1-2, 3, 4, 5, 6 and 7 points). The association between lifestyle and diabetes incidence was investigated using Cox proportional hazards regression models. The results showed that the multivariate-adjusted hazard ratios were 0.45 in subjects who scored 5 points, 0.39 in subjects who scored 6 points, and 0.31 in subjects who scored 7 points, compared with subjects who scored 1-2 points. These data indicate that the healthy behaviors prevent the incidence of diabetes.

Offering on-site mammography in workplaces improved screening rates: Cluster randomized controlled trial.

OBJECTIVES: Despite evidence of breast cancer screening efficacy, the screening rate has remained less than 50% in Japan. This study aimed to evaluate the effect of an environmental approach offering on-site mammography in workplaces. METHODS: Supermarket stores were randomly assigned into two groups, the intervention group (leaflet and mammography) and the control group (leaflet). From May to July 2018, participants in the intervention group were given a leaflet informing them of the subsidies for breast cancer screening and offered the opportunity to have mammography in their workplaces. Participants in the control group were given the same leaflet, but had to arrange their own screening outside the workplace. The primary outcome was the breast cancer screening rate in 2018. The odds ratio (OR) and 95% confidence interval (CI) for having screening in the intervention group compared with the control group were estimated using multilevel logistic regression. RESULTS: We analyzed data from 1624 participants (mean age 53 years) from 25 supermarket stores (intervention: 8 stores, control: 17 stores). Among participants who had not attended screening in the previous year, the screening rate was 7% in the control group and 53% in the intervention group, with an adjusted OR (95% CI) of 14.22 (8.97-22.54). The effect was greater in those who had never attended screening before. CONCLUSION: In a worksite-based cluster randomized controlled trial in Japanese supermarket stores, an environmental approach offering mammography in workplaces substantially increased the breast cancer screening rate within 1 year (UMIN000030465).

Self-measured home blood pressure highlights cardiovascular risk in women: the HOMED-BP study.

No studies examined sex differences in relation to the prognostic significance of self-measured home blood pressure (HBP). We compared the predictive power for the risk of cardiovascular events in 1547 women and 1516 men with hypertension using HBP captured at treatment-free baseline and during on-treatment follow-up, based on the Hypertension Objective Treatment Based on Measurement by Electrical Devices of Blood Pressure (HOMED-BP) study. To express the change in risk for the composite cardiovascular endpoint associated with a 1-SD increase in HBP at baseline or on treatment, we derived multivariable-adjusted hazard ratios (HR) based on a Cox regression model. Over a median follow-up of 7.3 years, 100 composite events occurred, including 40 events in women. In women, systolic HBP both at baseline and on-treatment showed significant risk increment (at baseline: HR per 1-SD increment, 1.62; 95% confidence interval [CI], 1.17-2.24. on-treatment: HR, 1.74; 95% CI, 1.32-2.29). However, systolic HBP at baseline did not predict cardiovascular events in men (P = 0.25). On-treatment HBP was significantly associated with cardiovascular risk (P ≤ 0.012) irrespective of sex. Nevertheless, the point estimate of HR for systolic HBP in men (1.33) was less than that in women (1.74), and the interaction of sex with 1 SD-increase in systolic HBP in cardiovascular risk was significant irrespective of baseline (P = 0.039) or follow-up (P = 0.040) measurement when they were mutually adjusted. The increase in cardiovascular risk with the systolic HBP was steeper in women than in men for both baseline and on-treatment. The current findings unveil the importance of the control of systolic HBP, especially in women. Clinical Trial Registration: UMIN Clinical Trial Registry ( http://www.umin.ac.jp/ctr ), Unique identifier: C000000137.

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.

The long-term reproducibility of the white-coat effect on blood pressure as a continuous variable from the Ohasama Study.

There is little information about the reproducibility of the white coat effect, which was treated as a continuous variable. To investigate a long-term interval reproducibility of the white-coat effect as a continuous variable. We selected 153 participants without antihypertensive treatment (men, 22.9%; age, 64.4 years) from the general population of Ohasama, Japan, to assess the repeatedly measured white-coat effect (the difference between blood pressures at the office and home) in a 4-year interval. The reproducibility was assessed by testing the intraclass correlation coefficient (two-way random effect model-single measures). The white-coat effect for systolic/diastolic blood pressure slightly decreased by 0.17/1.56 mmHg at the 4-year visit on average. The Bland-Altman plots showed no significant systemic error for the white-coat effects (P ≥ 0.24). The intraclass correlation coefficient (95% confidence interval) of the white-coat effect for systolic blood pressure, office systolic blood pressure, and home systolic blood pressure were 0.41 (0.27-0.53), 0.64 (0.52-0.74), and 0.74 (0.47-0.86), respectively. Change in the white-coat effect was mainly affected by a change in office blood pressure. Long-term reproducibility of the white-coat effect is limited in the general population without antihypertensive treatment. The change in the white-coat effect is mainly caused by office blood pressure variation.

Associations of Dental Health With the Progression of Hippocampal Atrophy in Community-Dwelling Individuals: The Ohasama Study.

BACKGROUND AND OBJECTIVES: Although tooth loss and periodontitis have been considered risk factors of Alzheimer disease, recent longitudinal researches have not found a significant association with hippocampal atrophy. Therefore, this study aimed to clarify a longitudinal association between the number of teeth present (NTP) and hippocampal atrophy dependent on the severity of periodontitis in a late middle-aged and older adult population. METHODS: This study included community-dwelling individuals aged 55 years or older who had no cognitive decline and had undergone brain MRI and oral and systemic data collection twice at 4-year intervals. Hippocampal volumes were obtained from MRIs by automated region-of-interest analysis. The mean periodontal probing depth (PD) was used as a measure of periodontitis. Multiple regression analysis was performed with the annual symmetric percentage change (SPC) of the hippocampal volume as the dependent variable and including an interaction term between NTP and mean PD as the independent variable. The interaction details were examined using the Johnson-Neyman technique and simple slope analysis. The 3-way interaction of NTP, mean PD, and time on hippocampal volume was analyzed using a linear mixed-effects model, and the interaction of NTP and time was examined in subgroups divided by the median mean PD. In all models, dropout bias was adjusted by inverse probability weighting. RESULTS: Data of 172 participants were analyzed. The qualitative interaction between NTP and the mean PD was significant for the annual SPC in the left hippocampus. The regression coefficient of the NTP on the annual SPC in the left hippocampus was positive (B = 0.038, p = 0.026) at the low-level mean PD (mean -1 SD) and negative (B = -0.054, p = 0.001) at the high-level mean PD (mean +1 SD). Similar results were obtained in the linear mixed-effects model; the interaction of NTP and time was significant in the higher mean PD group. DISCUSSION: In a late middle-aged and older cohort, fewer teeth were associated with a faster rate of left hippocampal atrophy in patients with mild periodontitis, whereas having more teeth was associated with a faster rate of atrophy in those with severe periodontitis. The importance of keeping teeth healthy is suggested.

Risk of smoking and body mass index for incidence of diabetes mellitus in a rural Japanese population.

OBJECTIVE: To assess the risk of smoking, body mass index (BMI), and both for incidence of diabetes in a rural Japanese population. METHOD: This study was a 10.1-year cohort study of 2070 men and 3802 women aged 40-69 years without diabetes at baseline who underwent a health check-up at one central hospital in Nagano Prefecture. Participants were classified according to a combination of smoking status and BMI. Participants were followed from 1990 to 2006. The incidence of diabetes was determined from fasting and random levels of plasma glucose, HbA(1c) levels or being under medical treatment for diabetes. RESULTS: Diabetes developed in 595 of the participants during 59,111 person-years of follow-up. In men, the multivariable-adjusted hazard ratios for incidence of diabetes compared with non-smokers of normal weight were as follows: 3.36 (2.02-5.60) in current smokers with normal weight and 1.70 (0.87-3.34) and 3.93 (2.22-6.96) in obese non-smokers and obese current smokers, respectively. In men the population-attributable fraction of diabetes onset due to current smoking, obesity and both were 22.0%, 2.5% and 11.2%, respectively. CONCLUSION: Regardless of BMI, smoking is an important risk factor for diabetes in male populations with a high prevalence of smoking.