Association of step counts with cognitive function in apparently healthy middle-aged and older Japanese men.

Background: Increasing physical activity may prevent cognitive decline. Previous studies primarily focused on older adults and used self-reported questionnaires to assess physical activity. We examined the relationship between step count, an objective measure of physical activity, and cognitive function in community-based middle-aged and older Japanese men. Methods: The Shiga Epidemiological Study of Subclinical Atherosclerosis randomly recruited community-dwelling healthy men aged 40-79 years from Shiga, Japan, and measured their step counts over 7 consecutive days using a pedometer at baseline (2006-2008). Among men who returned for follow-up (2009-2014), we assessed their cognitive function using the Cognitive Abilities Screening Instrument (CASI) score. We restricted our analyses to those with valid 7-day average step counts at baseline and those who remained free of stroke at follow-up (n = 676). Using analysis of covariance, we calculated the adjusted means of the CASI score according to the quartiles of the average step counts. Results: The mean (standard deviation) of age and unadjusted CASI score were 63.8 (9.1) years and 90.8 (5.8), respectively. The CASI score was elevated in higher quartiles of step counts (90.2, 90.4, 90.6, and 91.8 from the lowest to the highest quartile, respectively, [p for trend = 0.004]) in a model adjusted for age and education. Further adjustment for smoking, drinking, and other cardiovascular risk factors resulted in a similar pattern of association (p for trend = 0.005). Conclusion: In apparently healthy middle-aged and older Japanese men, a greater 7-day average step count at baseline was associated with significantly higher cognitive function score.

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

AIMS: High-sensitivity C-reactive protein (hsCRP) associates with atherosclerotic diseases such as stroke. However, previous results on the association between hsCRP levels and functional disability were controversial. METHODS: We analyzed 2,610 men and women who did not exhibit functional disability or death within the first 3 years of the baseline survey and those aged 65 years or older at the end of follow-up. The levels of hsCRP were assessed using latex agglutination assay at baseline survey from 2006 to 2014. Functional disability was followed up using the long-term care insurance (LTCI) program until November 1, 2019. Functional disability was defined as a new LTCI program certification. Cox proportional hazards model with competing risk analysis for death was used to evaluate the association between hsCRP levels and future functional disability. RESULTS: During a 9-year follow-up period, we observed 328 cases of functional disability and 67 deaths without prior functional disability incidence. The multivariable-adjusted hazard ratio (HR, 95% confidence interval [CI]) of functional disability in log-transferred hsCRP levels was 1.43 (1.22-1.67) in men and 0.97 (0.81-1.15) in women. When hsCRP level was analyzed as a categorical variable, low hsCRP levels (＜1.0 mg/l) as the reference, the multivariable-adjusted HR (95% CI) of functional disability in high hsCRP levels (≥ 3.0 mg/l) was 2.37 (1.56-3.62). Similar results were observed when stratified by sex, but it was not significant in women. CONCLUSIONS: This study demonstrates that low-grade systemic inflammation to assess hsCRP might predict the future incidence of functional disability, especially in men.

Associations of metabolic syndrome and metabolically unhealthy obesity with cancer mortality: The Japan Multi-Institutional Collaborative Cohort (J-MICC) study.

PURPOSE: The association between metabolic syndrome (MetS) and the risk of death from cancer is still a controversial issue. The purpose of this study was to examine the associations of MetS and metabolically unhealthy obesity (MUHO) with cancer mortality in a Japanese population. METHODS: We used data from the Japan Multi-Institutional Collaborative Cohort Study. The study population consisted of 28,554 eligible subjects (14,103 men and 14,451 women) aged 35-69 years. MetS was diagnosed based on the criteria of the National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III) and the Japan Society for the Study of Obesity (JASSO), using the body mass index instead of waist circumference. The Cox proportional hazards analysis was used to estimate adjusted hazard ratios (HR) and 95% confidence intervals (CI) for total cancer mortality in relation to MetS and its components. Additionally, the associations of obesity and the metabolic health status with cancer mortality were examined. RESULTS: During an average 6.9-year follow-up, there were 192 deaths from cancer. The presence of MetS was significantly correlated with increased total cancer mortality when the JASSO criteria were used (HR = 1.51, 95% CI 1.04-2.21), but not when the NCEP-ATP III criteria were used (HR = 1.09, 95% CI 0.78-1.53). Metabolic risk factors, elevated fasting blood glucose, and MUHO were positively associated with cancer mortality (P <0.05). CONCLUSION: MetS diagnosed using the JASSO criteria and MUHO were associated with an increased risk of total cancer mortality in the Japanese population.

Predictors of lower limb fractures in general Japanese: NIPPON DATA90.

OBJECTIVE: This study aimed to investigate the incidence rates and predictors of lower limb fractures in a general Japanese population. METHODS: NIPPON DATA is a nationwide, long-term, prospective cohort study of individuals who participated in the National Cardiovascular Survey Japan and the National Nutrition Survey in 1990. Overall, 3,134 individuals (1,827 women, 1,307 men) who participated in follow-up assessments in 1995, 2000, and/or 2006 were included in the present analysis. The outcomes of this study were lower limb fractures (including proximal femur fractures). RESULTS: The mean age at baseline was 63.8 years in women and 63.1 years in men. The average body mass index (BMI) was 23.3 kg/m2 in women and 22.9 kg/m2 in men. During a mean follow-up of 12.1 years, 271 total lower limb fractures were observed. In women, older age, lower BMI, and less intake of vegetables were associated with increased risks of proximal femur fractures. With regard to the outcome of total lower limb fractures, less intake of vegetables and regular exercise were significant predictors in women. Calcium intake was not significantly associated with proximal femur or total lower limb fractures. There were no significant predictors of proximal femur or total lower limb fractures in men, except for age. CONCLUSIONS: Aging was a significant risk factor for proximal femur and total lower limb fractures in both men and women. With regard to modifiable risk factors, low BMI and low intake of vegetables were associated with increased risks of proximal femur and/or total lower limb fractures in the general population of Japanese women.

Associations of breastfeeding history with metabolic syndrome and cardiovascular risk factors in community-dwelling parous women: The Japan Multi-Institutional Collaborative Cohort Study.

OBJECTIVE: The aim of the present study was to investigate the associations between breastfeeding and the prevalence of metabolic syndrome in community-dwelling parous women and to clarify whether the associations depend on age. METHODS: The present cross-sectional study included 11,118 women, aged 35-69 years. Participants' longest breastfeeding duration for one child and their number of breastfed children were assessed using a self-administered questionnaire, and their total breastfeeding duration was approximated as a product of the number of breastfed children and the longest breastfeeding duration. The longest and the total breastfeeding durations were categorized into none and tertiles above 0 months. Metabolic syndrome and cardiovascular risk factors (obesity, hypertension, dyslipidemia, and hyperglycemia) were defined as primary and secondary outcomes, respectively. Associations between breastfeeding history and metabolic syndrome or each cardiovascular risk factor were assessed using multivariable unconditional logistic regression analysis. RESULTS: Among a total of 11,118 women, 10,432 (93.8%) had ever breastfed, and 1,236 (11.1%) had metabolic syndrome. In participants aged <55 years, an inverse dose-response relationship was found between the number of breastfed children and the prevalence of metabolic syndrome; multivariable-adjusted odds ratios for 1, 2, 3, and ≥4 breastfed children were 0.60 (95% confidence interval [CI]: 0.31 to 1.17), 0.50 (95% CI: 0.29 to 0.87), 0.44 (95% CI: 0.24 to 0.84), and 0.35 (95% CI: 0.14 to 0.89), respectively. The longest and total breastfeeding durations of longer than 0 months were also associated with lower odds of metabolic syndrome relative to no breastfeeding history in participants aged <55 years. In contrast, all measures of breastfeeding history were not significantly associated with metabolic syndrome and cardiovascular risk factors in participants aged ≥55 years old. CONCLUSIONS: Breastfeeding history may be related to lower prevalence of metabolic syndrome in middle-aged parous women.

The association of reproductive history with hypertension and obesity according to menopausal status: the J-MICC Study.

Previous studies have reported that the number of pregnancies and childbirths affected the risk of cardiovascular diseases (CVDs). However, the influence of reproductive history on hypertension and obesity, which are important risk factors for CVDs, is still unclear. Moreover, this association may vary depending on menopausal status. We evaluated the association of reproductive history with hypertension and obesity using a large cross-sectional dataset from the Japan Multi-Institutional Collaborative Cohort Study (J-MICC Study). At the baseline survey, physical data, blood samples, and self-reported health questionnaires were collected. Participants with insufficient data were excluded, and 24,558 women from eight study regions were included in this study. Logistic regression analysis was conducted to evaluate the association of reproductive history with hypertension and obesity using multivariable-adjusted odds ratios. In premenopausal women, childbirth showed a generally protective effect on hypertension but not on obesity. In postmenopausal women, childbirth was positively associated with obesity and hypertension but not with hypertension after adjusting for BMI. In conclusion, reproductive history was associated with hypertension and obesity in a large Japanese population, and this association differed between premenopausal and postmenopausal women.

Alcohol consumption and cognitive function in elderly Japanese men.

Although heavy alcohol consumption has been identified as a risk factor for adverse cognitive functioning, it currently remains unclear whether moderate alcohol consumption exerts similar effects. Observational studies previously reported the potential benefits of moderate alcohol consumption on cognition, particularly in the elderly; however, these effects have not yet been demonstrated in Asian populations. The aim of the present study was to investigate the relationship between alcohol consumption levels and global and domain-specific cognitive functions in cognitively intact elderly Japanese men. Cross-sectional data from the Shiga Epidemiological Study of Subclinical Atherosclerosis (SESSA), an ongoing prospective, population-based study in Shiga, Japan, were used to examine the relationship between alcohol consumption and cognitive function. Men (n = 585) aged ≥65 years provided information on their weekly consumption of alcohol, and the data obtained were used to construct categories of never, ex- (quit before interview), very light (<14 g/day), light (14-23 g/day), moderate (>23-46 g/day), and heavy (>46 g/day) drinkers. Cognitive function was measured using the Cognitive Abilities Screening Instrument (CASI). A fractional logistic regression model adjusted for age, education, body mass index, smoking, exercise, hypertension, diabetes, and dyslipidemia showed that the CASI scores for global and domain-specific cognitive functions were not significantly different between all subgroups of current drinkers and never-drinkers. However, the CASI score of ex-drinkers (multivariable adjusted mean CASI score [SD]) was significantly lower than that of never-drinkers in the global [never vs. ex: 90.16 (2.21) vs. 88.26 (2.58)] and abstraction and judgment domain [never vs. ex: 9.48 (0.46) vs. 8.61 (0.57)]). The present results do not suggest any beneficial or adverse relationship between current alcohol consumption levels and cognitive functioning (both global and domain specific) in elderly Japanese men; however, low cognitive function among ex-drinkers warrants future investigations to identify the factors causing drinkers to quit.

Proteinuria and Reduced Estimated Glomerular Filtration Rate are Independently Associated With Lower Cognitive Abilities in Apparently Healthy Community-Dwelling Elderly Men in Japan: A Cross-sectional Study.

BACKGROUND: The association of proteinuria and reduced estimated glomerular filtration rate (eGFR) with cognition needs more clarification. We cross-sectionally examined whether proteinuria and reduced eGFR, even in moderate stages, were independently associated with lower cognition in a community-based sample of elderly men. METHODS: Our cohort initially comprised 1,094 men aged 40-79 years from a random sample from Shiga, Japan in 2006-2008. Of 853 men who returned for the follow-up examination (2009-2014), we analyzed 561 who were ≥65 years, free of stroke, and completed the Cognitive Abilities Screening Instrument (CASI) at follow-up (higher CASI scores [range 0 to 100] indicate better cognition). Proteinuria was assessed via dipstick. eGFR was calculated according to the Chronic Kidney Disease Epidemiology Collaboration Equation. Participants were divided into three groups either by eGFR (≥60, 59-40, and <40 mL/min/1.73 m2) or by proteinuria (no, trace, and positive), considered normal, moderate, and advanced, respectively. Using linear regression, we computed mean CASI score, with simultaneous adjustment for proteinuria and eGFR in addition to other potential confounders. RESULTS: Significant trends of lower cognition were observed across the groups of worse proteinuria and lower eGFR independently: multivariable-adjusted mean CASI scores were 90.1, 89.3, and 88.4 for proteinuria (Ptrend = 0.029), and 90.0, 88.5, and 88.5 for eGFR (Ptrend = 0.015) in mutual-adjustment model. CONCLUSIONS: Proteinuria and reduced eGFR, even in their moderate stages, were independently associated with lower cognition in a community-based sample of elderly men. The results suggest the importance of proteinuria and low eGFR for early detection and prevention of cognitive decline.

Associations of Overweight, Obesity, and Underweight With High Serum Total Cholesterol Level Over 30 Years Among the Japanese Elderly: NIPPON DATA 80, 90, and 2010.

BACKGROUND: The trend of association between overweight and high serum total cholesterol (TC) among the elderly is unclear. In addition, there is little evidence of risk of underweight for high TC. Therefore, we examined the trend of association of overweight or underweight with high TC among Japanese elderly people using nationwide population-based data. METHODS: Data of the National Survey on Circulatory Disorders and National Health and Nutrition Survey for 1980, 1990, 2000, and 2010 were used in the analysis. High TC was defined as 220 mg/dL and above. For participants aged ≥50 years, sex-specific odds ratios (ORs) of overweight or underweight compared with normal body mass index participants for high TC were calculated using a logistic regression model adjusted for age, smoking, drinking, exercise, food, and treatment of hyperlipidemia. RESULTS: A total of 5,734, 4,673, 5,059, and 2,105 participants enrolled in these surveys in 1980, 1990, 2000, and 2010, respectively. Although overweight was positively and significantly associated with high TC in 1980, the association has gradually weakened since (ORs in 1980 and 2010 were 2.44; 95% confidence interval [CI], 1.83-3.24 and 0.92; 95% CI, 0.66-1.27 among men and 1.43; 95% CI, 1.18-1.72 and 1.08; 95% CI, 0.81-1.44 among women, respectively). While underweight was inversely and significantly associated with high TC in 1980, the association also gradually weakened among women (ORs in 1980 and 2010 were 0.28; 95% CI, 0.12-0.60 and 0.37; 95% CI, 0.10-1.28 among men and 0.39; 95% CI, 0.26-0.57 and 0.96; 95% CI, 0.58-1.57 among women, respectively). CONCLUSIONS: These findings provide evidence that high TC prevention efforts must expand the target to not only overweight but also to normal and underweight people.

Erratum: Diurnal variation of urinary sodium-to-potassium ratio in free-living Japanese individuals.

This corrects the article DOI: 10.1038/hr.2016.187.

Diurnal variation of urinary sodium-to-potassium ratio in free-living Japanese individuals.

High sodium-to-potassium ratios are associated with elevated blood pressure levels and an increased risk of cardiovascular diseases. We aimed to determine whether urinary sodium-to-potassium ratios fluctuate diurnally during the day to understand measured values of casual urinary sodium-to-potassium ratios. A total of 13,277 casual urine specimens were collected under free-living conditions from 122 Japanese normotensive and hypertensive individuals. Participants collected all casual urine samples in aliquot tubes, reported urine volumes and the time at each voiding for 10-22 days. Then, specimens were classified into hourly data. Diurnal patterns of urinary sodium-to-potassium ratios and urinary concentrations of sodium and potassium were evaluated. Overall mean values of hourly urinary sodium-to-potassium ratios were highest (4.1-5.0) in the early morning, lower (3.3-3.8) in the daytime and higher (4.0-4.4) toward evening hours. The mean urinary sodium and potassium concentrations were the lowest (90-110 and 24-32 mmol l-1, respectively) during the early morning and higher (110-140 and 35-43 mmol l-1, respectively) after mid-morning. Diurnal variability of potassium concentrations was larger than for sodium concentrations. Diurnal variations in urinary sodium-to-potassium ratios were comparable between normotensive and hypertensive individuals, between hypertensive individuals with and without antihypertensive medications, and among age and gender-specific subgroups. Overall mean hourly urinary sodium-to-potassium ratios fluctuated diurnally under free-living conditions and were higher during the morning and evening and lower during the daytime compared with 24-h urinary sodium-to-potassium ratios. Diurnal variation in urinary sodium-to-potassium ratios should be considered to understand actual daily dietary levels and avoid over- and under-estimation in clinical practice.

Association between Pulse Wave Velocity and Coronary Artery Calcification in Japanese men.

AIM: Pulse wave velocity (PWV) is a simple and valid clinical method for assessing arterial stiffness. Coronary artery calcification (CAC) is an intermediate stage in the process leading to overt cardiovascular disease (CVD) and an established determinant of coronary artery disease. This study aimed to examine the association between PWV and CAC in a population-based sample of Japanese men. METHODS: This is a cross-sectional study of 986 randomly selected men aged 40-79 years from Shiga, Japan. CVD-free participants were examined from 2006 to 2008. Brachial-ankle PWV (baPWV) was measured using an automatic waveform analyzer. CAC was assessed using computed tomography. Agatston scores ≥ 10 were defined as the presence of CAC. RESULTS: Prevalence of CAC progressively increased with rising levels of baPWV: 20.6%, 41.7%, 56.3%, and 66.7% across baPWV quartiles ＜ 1378, 1378-1563, 1564-1849, and ＞ 1849 cm/s (P ＜ 0.001 for trend). Associations remained significant after adjusting for age and other factors, including body mass index, systolic blood pressure, pulse rate, total and high-density lipoprotein cholesterol, hemoglobin A1c, drinking, smoking and exercise status, and the use of medication to treat hypertension, dyslipidemia and diabetes (P=0.042 for trend). The optimal cutoff level of baPWV to detect CAC was 1612 cm/s using receiver operating characteristic curve analysis. CONCLUSIONS: Arterial stiffness as defined by an elevated baPWV is associated with an increased prevalence of CAC in a general population-based setting among Japanese men.

Secular trends of the impact of overweight and obesity on hypertension in Japan, 1980-2010.

The prevalence of overweight (body mass index (BMI)=25.0-29.9 kg m(-)(2)) and obesity (⩾30.0 kg m(-)(2)) has been increasing over the last several decades in Japan. We examined trends of the impact of overweight and obesity on hypertension (systolic/diastolic blood pressure ⩾140/90 mm Hg or antihypertensive drugs use) using four national surveys in Japan, from which the participants were randomly sampled from the entire population. Study participants aged 30-79 years were selected for each survey (10 370 in 1980, 8005 in 1990, 5327 in 2000 and 2547 in 2010). The results showed that the impact of overweight and obesity on hypertension had increased significantly (P=0.040 and 0.006 in men and women, respectively). From 1980 to 2010, the multivariable-adjusted odds ratios for hypertension, comparing overweight and obesity with normal weight (BMI =18.5-24.9 kg m(-)(2)), went from 1.94 (95% confidence intervals: 1.64, 2.28) to 2.82 (2.07, 3.83) in men, and from 2.37 (2.05, 2.73) to 3.48 (2.57, 4.72) in women. Most of the association was observed in overweight participants, as only 3% of the Japanese were obese. In addition to the relationship between excessive BMI and other adverse health conditions, the rise in the association with hypertension increases the urgency in addressing weight control. We need to address the overweight and obesity epidemic.

High-density lipoprotein particle concentration and subclinical atherosclerosis of the carotid arteries in Japanese men.

OBJECTIVE: The association of high-density lipoprotein particle (HDL-P) with atherosclerosis may be stronger than that of HDL-cholesterol (HDL-C) and independent of conventional cardiovascular risk factors. Whether associations persist in populations at low risk of coronary heart disease (CHD) remains unclear. This study examines the associations of HDL-P and HDL-C with carotid intima-media thickness (cIMT) and plaque counts among Japanese men, who characteristically have higher HDL-C levels and a lower CHD burden than those in men of Western populations. METHODS: We cross-sectionally examined a community-based sample of 870 Japanese men aged 40-79 years, free of known clinical cardiovascular disease (CVD) and not on lipid-lowering medication. Participants were randomly selected among Japanese living in Kusatsu City in Shiga, Japan. RESULTS: Both HDL-P and HDL-C were inversely and independently associated with cIMT in models adjusted for conventional CHD risk factors, including low-density lipoprotein cholesterol (LDL-C) and diabetes. HDL-P maintained an association with cIMT after further adjustment for HDL-C (P < 0.01), whereas the association of HDL-C with cIMT was noticeably absent after inclusion of HDL-P in the model. In plaque counts of the carotid arteries, HDL-P was significantly associated with a reduction in plaque count, whereas HDL-C was not. CONCLUSION: HDL-P, in comparison to HDL-C, is more strongly associated with measures of carotid atherosclerosis in a cross-sectional study of Japanese men. Findings demonstrate that, HDL-P is a strong correlate of subclinical atherosclerosis even in a population at low risk for CHD.

Lethal effects of short-wavelength visible light on insects.

We investigated the lethal effects of visible light on insects by using light-emitting diodes (LEDs). The toxic effects of ultraviolet (UV) light, particularly shortwave (i.e., UVB and UVC) light, on organisms are well known. However, the effects of irradiation with visible light remain unclear, although shorter wavelengths are known to be more lethal. Irradiation with visible light is not thought to cause mortality in complex animals including insects. Here, however, we found that irradiation with short-wavelength visible (blue) light killed eggs, larvae, pupae, and adults of Drosophila melanogaster. Blue light was also lethal to mosquitoes and flour beetles, but the effective wavelength at which mortality occurred differed among the insect species. Our findings suggest that highly toxic wavelengths of visible light are species-specific in insects, and that shorter wavelengths are not always more toxic. For some animals, such as insects, blue light is more harmful than UV light.