Triglyceride/high-density lipoprotein cholesterol ratio may be a better index of cardiometabolic risk in women than in men in Japan.

BACKGROUND AND AIMS: Few data exist regarding the gender differences in the relationship between triglyceride/high-density lipoprotein cholesterol (TG/HDL-C) ratio and cardiometabolic risk leading to atherosclerotic cardiovascular disease (ASCVD). We investigated, by gender, the association between the TG/HDL-C ratio and metabolic syndrome (MetS) and its components in the Japanese, who are less obese than their Western counterparts. METHODS AND RESULTS: A population consisting of 10,373 participants (average age, 47.6 ± 12.6 years, 60.9 % men) at the Health Planning Center of Nihon University Hospital between April 2019 and March 2020 was studied using a cross-sectional study method. The TG/HDL-C ratio and proportion of visceral obesity increased approximately parallelly with age in women; however, these parameters did not change proportionally with age in men. Accordingly, receiver operating characteristic analysis revealed the accuracy of the TG/HDL-C ratio as a predictor of visceral obesity based on the Japanese MetS criteria (women vs. men: area under the curve, 0.797 vs. 0.712, p < 0.0001; sensitivity, 82.4 % vs. 59.9 %; specificity, 61.1 % vs. 71.1 %; cutoff value, 1.075 vs. 1.933, respectively). Furthermore, a higher TG/HDL-C ratio in women reflected the status of MetS and its components compared with men in multi-logistic regression analysis. CONCLUSION: An increased TG/HDL-C ratio in women may be involved in MetS and its components compared to men. We may pay attention to visceral obesity and increased TG/HDL-C ratio to prevent ASCVD risk in women, even in the Japanese population, which generally contains a lower proportion of obesity than in Western populations.

Association of Higher N-3 Polyunsaturated Fatty Acid Consumption and Aerobic Exercise with Lower Neutrophil-to-Lymphocyte Ratio: Implications of Anti-Atherosclerotic Effect of Fish Consumption.

INTRODUCTION: N-3 polyunsaturated fatty acids (n-3 PUFAs), abundant in oily fish, exert anti-inflammatory cardiovascular protective effects. We aimed to investigate the association between fish-derived n-3 PUFAs, lifestyle habits, and neutrophil-to-lymphocyte ratio (NLR), an atherosclerotic cardiovascular disease (ASCVD) marker. METHODS: This cross-sectional study included 6,950 participants with no history of ASCVD, who underwent annual health check-ups (average age, 46.3 ± 13.0 years; male:female ratio, 58.8%) between April 2019 and March 2020 at the Health Planning Center, Nihon University Hospital. We calculated n-3 PUFA consumption using a questionnaire and the Japan National Health and Nutrition Survey. RESULTS: The average fish consumption frequency and fish-derived n-3 PUFA consumption were 2.20 ± 1.28 days/week and 5.20 ± 3.11 g/week, respectively. A higher fish-derived n-3 PUFA consumption was associated with a lower NLR. Multiple-stepwise regression analysis revealed that higher fish-derived n-3 PUFA consumption and more aerobic exercise habits were significant independent determinants of lower NLR. Furthermore, higher fish-derived n-3 PUFA consumption was associated with habitual aerobic exercise habits. CONCLUSION: Thus, higher fish-derived n-3 PUFA consumption and more aerobic exercise habits may be synergistically associated with lower NLR. This association may explain the preventive effects of fish consumption on the ASCVD risk.

Higher frequency of fish intake and healthy lifestyle behaviors may be associated with a lower platelet count in Japan: Implication for the anti-atherosclerotic effect of fish intake.

BACKGROUND: Habitual fish intake and healthier lifestyles are associated with a lower risk of atherosclerotic cardiovascular disease (ASCVD). Higher platelet counts (PLCs) are reportedly associated with higher ASCVD events. We aimed to investigate the association between fish intake and lifestyle with PLCs. METHODS: We conducted a cross-sectional study in a cohort of 9329 participants (average age: 46.9 ± 12.9 years; 58.9% men) with no history of ASCVD registered at the Health Planning Center of Nihon University Hospital in 2019. RESULTS: The average fish intake frequency was 2.15 ± 1.28 days/week. As fish intake frequency increased (0, 1, 2, 3, 4, 5, 6, and 7 days), PLC decreased significantly (p < 0.0001). Multivariable logistic regression analysis showed that higher fish intake frequency tended to be a determinant of lower PLC. Aerobic exercise habits and sleep duration were independent negative determinants of PLC. Cigarette smoking habits were a positive independent determinant of PLC. Furthermore, with increasing fish intake frequency, the proportion of participants with habitual aerobic exercise, non-smoking habits, and longer sleep duration increased (p < 0.0001 for all). Higher n-3 polyunsaturated fatty acid (n-3 PUFA), calculated based on data from the Japanese National Health and Nutrition Survey, intake was associated with a lower PLC. CONCLUSION: Higher fish intake and healthier lifestyle behaviors may be comprehensively associated with lower PLCs. The intake of N-3 PUFA with anti-inflammatory effects, rich in fish, may also be related to the lower PLC. This association may explain the preventive effects of fish intake on ASCVD risk.

Association of Glycated Hemoglobin Level with Self-Reported Chewing Problems in Elderly Community-Dwelling Individuals in Japan.

Purpose: Chewing problems are associated with increased mortality, geriatric syndromes and poor activities of daily living. Starting in 2018, in Japan, a self-reported questionnaire investigating chewing status was implemented in the annual health checkup program. Considering the bidirectional association between hyperglycemia and poor oral health, it is hypothesized that people with self-reported chewing problems will have relatively poor glycemic profiles. We investigated the metabolic characteristics of elderly community dwellers with self-reported chewing problems, as well as the association between the problems and HbA1c levels. Patients and Methods: This was a retrospective, cross-sectional study. We reviewed the data of 1018 adults ≥ 65 years of age who had undergone an annual health checkup at Nihon University Hospital during the period from January 2019 through December 2019. The presence of chewing problems was investigated using a self-reported questionnaire constructed based on guidance provided by the Japanese government. Results: In the 1018 participants, the overall prevalence of chewing problems was 10.4%. Participants with chewing problems showed significantly higher levels and worse categories of HbA1c than those without such problems (HbA1c < 6.0%, 42.5% vs 54.8%; HbA1c 6.0-6.9%, 41.5% vs 37.0%; HbA1c ≥ 7.0%, 16.0% vs 8.2%, p = 0.008). Participants with HbA1c ≥ 7.0% have a significantly increased risk of chewing problems as compared to those with HbA1c < 6.0% (odds ratio 2.76, p = 0.002), even after adjusting for the effects of age, sex, body mass index, eating behaviors, and history of diabetes mellitus. Conclusion: HbA1c ≥ 7.0% is associated with self-reported chewing problems in elderly Japanese community-dwellers. We thus recommend a proactive assessment of oral conditions for this population.

Habitual fish consumption and healthy lifestyle behaviours may be associated with higher total serum bilirubin level and anti-inflammatory activity: a cross-sectional study.

Habitual fish consumption and a healthy lifestyle are associated with lower atherosclerotic CVD (ASCVD) risk. Mildly elevated bilirubin, an end product of Hb metabolism, may be associated with anti-inflammatory effects, suppressing ASCVD risk. No data exist on the relationship between fish consumption, total serum bilirubin (TSB) and inflammation in clinical settings. We conducted a cross-sectional study between April 2019 and March 2020 in a cohort of 8292 participants (average age, 46·7 (sd 12·9) years and 58·9 % men) with no history of ASCVD and TSB concentrations < 2·0 mg/dl. Multiple stepwise regression analysis showed Hb concentrations were a solid positive determinant of TSB concentrations (ß = 0·302, P< 0·0001). Fish consumption (ß = 0·025, P= 0·019) and aerobic exercise (ß = 0·021, P= 0·043) were statistically weak but significantly positive determinants of TSB concentrations. Cigarette smoking negatively affected TSB concentrations (ß = −0·104, P< 0·0001). Moreover, with increasing fish consumption, the proportion of participants with a habit of cigarette smoking decreased, and that of participants who engaged in aerobic exercises increased (P< 0·0001 for both). Furthermore, as TSB concentrations increased, the leukocyte counts and C-reactive protein concentrations decreased (P< 0·0001 for both). In conclusion, despite the lesser relevance given to TSB concentrations than Hb concentrations, higher fish consumption and healthier lifestyle behaviours related to fish consumption habits may be additively or synergistically associated with higher TSB concentrations and anti-inflammatory activity, leading to attenuated ASCVD risk. Further investigations are needed to clarify the causal relationships between these factors.

Inadequate sleep duration may attenuate the anti-inflammatory effects of fish consumption in a healthy Japanese population: a cross-sectional study.

High fish consumption may be associated with lower inflammation, suppressing atherosclerotic CVD (ASCVD). Long sleep duration, as well as short sleep, may contribute to inflammation, thus facilitating ASCVD. This study investigated the overall association between fish consumption, sleep duration and leucocytes count. We conducted a cross-sectional study between April 2019 and March 2020 with a cohort of 8947 apparently healthy participants with no history of ASCVD (average age, 46·9 ± 12·3 years and 59 % males). The average frequency of fish consumption and sleep duration were 2·13 ± 1·26 d/week and 6·0 ± 0·97 h/d. Multivariate linear regression analysis revealed that increased fish consumption was an independent determinant of sleep duration (ß = 0·084, P < 0·0001). Additionally, habitual aerobic exercise (ß = 0·059, P < 0·0001) or cigarette smoking (ß = −0·051, P < 0·0001) and homoeostasis model assessment-insulin resistance (HOMA-IR) (ß = −0·039, P = 0·01) were independent determinants of sleep duration. Furthermore, multivariate linear regression analysis identified fish consumption as an independent determinant of leucocytes count (ß = −0·091, P < 0·0001). However, a significant U-shaped curve was found between leucocytes count and sleep duration, with 6­7 h of sleep as the low value (P = 0·015). Higher fish consumption may be associated with a lower leucocytes count in the presence of adequate sleep duration and healthy lifestyle behaviors. However, long sleep duration was also related to increased inflammation, even in populations with high fish consumption. Further studies are needed to clarify the causality between these factors.

Associations of higher fish consumption and lifestyle with lower monocyte/HDL-C ratio in a Japanese population: Implication for the anti-atherosclerotic effect of fish consumption.

BACKGROUND: High fish consumption may be involved in lowering inflammation, resulting in the suppression of atherosclerotic cardiovascular disease (ASCVD) development. The monocyte/high-density lipoprotein cholesterol (HDL-C) ratio (MHR) is reported as a novel inflammatory marker of the development of atherosclerosis. We investigated the relationship between fish consumption, MHR, and lifestyle behaviors and explored the foundation of risk stratification of ASCVD using serum HDL-C, MHR, and fish consumption. METHODS: We conducted a cross-sectional study among 6841 adults at the Health Planning Center of Nihon University Hospital between April 2019 and March 2020. We calculated the amount of fish consumption based on Japan's National Nutrition Survey results. RESULTS: The median (interquartile range) fish consumption was 111.4 (67.2/169.2) g per week. As fish consumption increased, MHR decreased significantly (p < 0.0001). Multivariate linear regression analysis identified increased fish consumption as an independent negative determinant of a decreased MHR (ß = -0.050, p < 0.0001). Additionally, healthier lifestyle behaviors (sleep duration and cigarette smoking habit) were also significantly associated with MHR (ß = -0.025, p = 0.027 and ß = 0.146, p < 0.0001, respectively). Furthermore, risk stratification of ASCVD could be developed by combining the HDL-C level and fish consumption with the MHR, indicating that even with similar HDL-C levels, higher MHR and lower fish consumption are associated with a higher risk of ASCVD. Multi-logistic regression analysis with the MHR quartile as an independent variable also showed that the increase in quartile was associated with the exacerbation of visceral obesity and glucose/lipid markers. CONCLUSIONS: A higher fish consumption may be associated with a lower MHR as well as healthier lifestyle behaviors. Moreover, we proposed the concept of risk stratification through relationships with MHR, HDL-C, and fish consumption to reduce ASCVD risk. Further studies are required to dissect the causal relationships between these results.

The Frequency and Amount of Fish Intake Are Correlated with the White Blood Cell Count and Aerobic Exercise Habit: A Cross-sectional Study.

Objective We investigated the relationship between the amount and frequency of fish intake, and the white blood cell (WBC) count and aerobic exercise habits. Methods We conducted a cross-sectional study between April 2019 and March 2020 at the Health Planning Center of Nihon University Hospital on a cohort of 8,981 male subjects. Results The average amount and frequency of fish intake were 134±85 g/week and 2.14±1.28 days/week, respectively. The WBC count decreased significantly as the amount of fish intake increased (p<0.0001). According to a multivariate regression analysis, a high fish intake amount (ß=-0.082, p<0.0001) and regular aerobic exercise (ß=-0.083, p<0.0001) were independent determinants of a low WBC count. The proportion of subjects engaged in regular aerobic exercise increased with an increase in the amount of fish intake (p<0.0001). Furthermore, the amount and frequency of fish intake significantly correlated with the amount of n-3 polyunsaturated fatty acid intake determined using the Japan's National Nutrition Survey results (both r=0.962 and 0.958). Therefore, the amount of fish intake could be substituted by the average number of days of fish intake per week. Conclusion A high fish intake was an independent determinant of a low WBC count and engagement in regular aerobic exercise, regardless of whether the fish intake was defined by the amount or frequency of fish intake. However, since fish intake frequency can be measured more easily, this may be used to measure the fish intake.

Impact of Female Sex on the Susceptibility to Hypernatremia Among Older Community-Dwelling Individuals in Japan.

PURPOSE: Older individuals are at high risk for hypernatremia. However, actual data on serum sodium levels and differences between the sexes remain unclear in the older Japanese population. This study aimed to describe the data regarding serum sodium level and hypernatremia prevalence and to investigate whether female sex is associated with an increased risk of hypernatremia. PATIENTS AND METHODS: We retrospectively analyzed the data of adults aged ≥65 years without severely reduced kidney function who underwent an annual health checkup in 2019. Serum sodium levels were investigated as the outcome and corrected for glucose, if necessary. Clinical characteristics were compared between women and men. RESULTS: In the 903 participants consisting of 273 women and 630 men who were enrolled in this study, the overall prevalence of hypernatremia, defined as a serum sodium level ≥145 mmol/L, was 12.5%. Female participants showed significantly more frequent hypernatremia than male participants (17.6% vs 10.3%, p = 0.003) and higher serum sodium levels (median [interquartile range]; 143.0 [142.0, 144.0] vs 142.4 [141.5, 144.0], p <0.001). Serum creatinine (sCr), but not estimated glomerular filtration rate (eGFR), was correlated with serum sodium levels (rs = -0.108, p = 0.001). In the binary logistic regression analysis, female sex was significantly associated with hypernatremia (odds ratio, 1.89; 95% confidence interval, 1.23-2.89; p = 0.004) even after adjusting for age, alcohol use, antihypertensive agent use, body mass index, and winter season. The association between female sex was reduced and no longer significant after adjusting for sCr, although the association remained unchanged after adjustment for eGFR. CONCLUSION: One-eighth of the older community dwellers in Japan exhibits hypernatremia after an overnight fast, and female sex is a significant risk factor. Since sCr is a surrogate of muscle mass, smaller muscle mass possibly mediates the association between female sex and hypernatremia.

Combined Higher Frequency Fish Consumption and Healthy Lifestyle May Lower the Triglyceride/HDL-C Ratio in Middle-Aged Japanese Males: Anti-Atherosclerotic Effect of Fish Consumption.

BACKGROUND: Fish consumption may be associated with a low risk of coronary artery disease. We aimed to investigate whether higher fish consumption results in improved lifestyle behaviors and thus lower triglyceride/high-density lipoprotein cholesterol (TG/HDL-C) ratio - a predictor of atherosclerotic cardiovascular disease (ASCVD). METHODS AND RESULTS: This cross-sectional study included 2,947 middle-aged Japanese males with no history of ASCVD or lipid-modifying therapy, who presented at the Health Planning Center of Nihon University Hospital between April 2018 and March 2019. We performed an analysis of variance using fish consumption as a categorical variable (0-2 days, 3-4 days, or 5-7 days per week). The serum TG/HDL-C ratio in the 5-7 days fish consumption group was significantly lower than those in the 0-2 and 3-4 days fish consumption groups (p < 0.0001 and p < 0.01, respectively). Multiple regression stepwise analysis revealed that weekly fish consumption negatively and independently determined the TG/HDL-C ratio (ß = -0.061, p = 0.001). As fish consumption increased, the proportion of subjects with smoking habits decreased (p = 0.014), those engaging in aerobic exercises and aggressive daily physical activity increased (p < 0.0001 for both), and those with alcohol habit increased (p < 0.0001). In addition, we developed the risk stratification for ASCVD by combining the serum HDL-C level and the serum TG/HDL-C ratio with fish consumption. CONCLUSION: Increased frequency of fish consumption and improved lifestyle behaviors due to daily fish intake may work additively to lower the serum TG/HDL-C ratio. These associations may explain why high fish consumption is associated with a lower risk of ASCVD. Our findings may help physicians and nutritionists in treating patients with heart diseases and metabolic conditions by recommending a high fish diet in middle-aged Japanese males.

Higher Frequency of Fish Intake May Be Associated with a Lower Neutrophil/Lymphocyte Ratio: Anti-Atherosclerotic Effects of Fish Consumption.

BACKGROUND: Higher fish consumption has been reported to be associated with a lower incidence of coronary artery disease (CAD). An elevated neutrophil/lymphocyte ratio (NLR), a marker of systemic inflammation, is reportedly associated with the development of adverse CAD events. We hypothesized that a higher fish intake was associated with a lower NLR. METHODS AND RESULTS: This cross-sectional study was conducted in a cohort of 8,237 Japanese subjects who had no history of atherosclerotic cardiovascular disease registered at the Health Planning Center of Nihon University Hospital between April 2018 and March 2019. The average weekly frequency of fish intake was 2.32 ± 1.31 days. The NLR decreased significantly as the weekly frequency of fish intake (0 day, 1-2 days, 3-4 days, or 5-7 days) increased (p = 0.001). A multiple stepwise regression analysis identified the weekly frequency of fish intake (ß = -0.045, p < 0.0001) and habitual alcohol intake (ß = -0.051, p < 0.0001) as significant but weak, negative, and independent determinants of the NLR. Conversely, the presence of metabolic syndrome (ß = 0.046, p < 0.0001), the presence of treatment for diabetes mellitus (ß = 0.054, p < 0.0001), and the presence of treatment for hypertension (ß = 0.043, p < 0.0001) were significant positive and independent determinants of the NLR. CONCLUSIONS: The present results suggest that a higher frequency of fish intake appears to be associated with a lower NLR, suggesting an anti-systemic inflammation effect. This association may partially explain the preventive effects of a higher fish intake on CAD events.

Gender differences in the associations among fish intake, lifestyle, and non-HDL-C level in Japanese subjects over the age of 50 years: Anti-atherosclerotic effect of fish consumption.

BACKGROUND AND AIMS: Higher fish consumption may lead to the suppression of atherogenesis. The present study was aimed at investigating the gender differences in association with the frequency of fish intake, lifestyle behaviors and serum non-high-density lipoprotein cholesterol (non-HDL-C) levels. METHODS AND RESULTS: This cross-sectional study was conducted in a cohort of 4320 (2479 males, 1570 females) healthy Japanese subjects over 50 years of age registered at the Health Planning Center of Nihon University Hospital between April 2018 and March 2019. The average weekly frequency of fish intake was 2.58 ± 1.39 days in males and 2.42 ± 1.36 days in females. In males, the serum non-HDL-C level decreased significantly as the weekly frequency of fish intake (0-1 days, 2-3 days, 4-5 days, or 6-7 days) increased (p < 0.0001). Multiple stepwise regression analysis identified the weekly frequency of fish intake (ß = -0.056, p = 0.004) and habitual aerobic exercise (ß = -0.063, p = 0.001) as independent determinants of the serum non-HDL-C level. On the other hand, no such associations were observed in females. However, the proportion of subjects engaging in habitual aerobic exercise increased as the frequency of fish intake increased even among females. CONCLUSIONS: A higher frequency of fish intake may be associated with healthier lifestyle behaviors and lower non-HDL-C levels in males, but not in females. There appear to be gender differences in the relationships between the intake of fish and lifestyle behaviors on lipid metabolism. CLINICAL TRIAL REGISTRATION: umin (http://www.umin.ac.jp/) Study ID: UMIN000035899.

Association among daily fish intake, white blood cell count, and healthy lifestyle behaviors in an apparently healthy Japanese population: implication for the anti-atherosclerotic effect of fish consumption.

Higher fish consumption has been reported to be associated with a lower incidence of coronary artery disease. We hypothesized that a higher frequency of fish intake may be associated with lower peripheral white blood cell (WBC) counts, a marker of chronic inflammation, which is known to be involved in the development of atherosclerotic cardiovascular disease (ASCVD), and a healthy lifestyle. This cross-sectional study was conducted between April 2018 and August 2018 at the Health Planning Center of Nihon University Hospital in a cohort of 4105 apparently healthy subjects. The average frequency of fish intake was 2.3 ± 1.3 days per week. The WBC count decreased significantly as the frequency of fish intake (0-2 days, 3-4 days, or 5-7 days per week) increased (s < 0.0001). Multivariate linear regression analysis identified higher weekly frequency of fish intake as a significant independent determinant of a lower WBC count (ß = - 0.051, p = 0.001). Furthermore, as the weekly frequency of fish intake increased, the proportion of habitual cigarette smokers decreased (p = 0.021), that of subjects engaging in habitual aerobic exercises increased (p < 0.0001), and the weekly alcohol intake frequency increased (p < 0.0001). Moreover, the above-mentioned lifestyle behaviors were also independent determinants of the WBC count. These results suggest that a high frequency of fish intake might be associated with healthier lifestyle behaviors as well as lower WBC counts, and thus may both exert beneficial anti-inflammatory effects and represent a component of healthier lifestyle behaviors associated with a lower risk of ASCVD in Japanese. This association may be partially related to the preventive effects of a higher fish intake on ASCVD events. CLINICAL TRIAL REGISTRATION: UMIN ( http://www.umin.ac.jp/ ) Study ID: UMIN000039197 retrospectively registered 1 February 2020.

Effect of Adult Weight Gain on Non-Alcoholic Fatty Liver Disease and Its Association with Anthropometric Parameters in the Lean Japanese Population.

Limited data are available on the prevalence of non-alcoholic fatty liver disease (NAFLD) and its association with adult weight gain (AWG) in the lean population. This study aimed to determine the prevalence of NAFLD and to investigate whether AWG is associated with NAFLD in the lean Japanese population. We retrospectively analyzed patients who underwent abdominal ultrasonography as part of the annual health checkup between January 2019 and December 2019. Participants were classified into two groups: those with AWG ≥ 10 kg (AWG group, n = 497), and those without gain (non-AWG group, n = 3006). To adjust for the confounding effects, we generated 482 pairs using 1:1 propensity score matching. The associations between AWG and NAFLD, anthropometric parameters and NAFLD were investigated using univariate logistic regression analysis. We identified NAFLD in 197 (5.6%) participants. AWG was significantly associated with NAFLD (odds ratio (OR), 1.81; p = 0.003). Waist circumference was significantly associated with NAFLD in both the AWG (OR, 1.24; p < 0.001) and non-AWG groups (OR, 1.17; p < 0.001). The association between body mass index and NAFLD existed in the former group (OR, 1.76; p < 0.001), but was not significant in the latter group. AWG is a risk factor for NAFLD even in the lean Japanese population, and associations between anthropometric parameters and NAFLD become stronger if AWG coexists.

Seasonal variation in hydration status among community-dwelling elderly in Japan.

AIM: While the heat during the summer season may dehydrate the elderly, little is known about the seasonal variation in dehydration. This study aimed to investigate the seasonal variation in hydration status among the community-dwelling elderly in Japan. METHODS: We retrospectively analyzed the data collected after an overnight fast of adults aged ≥65 years who had no advanced kidney disease and underwent an annual health checkup at Nihon University Hospital between January and December 2019. Participants were classified according to their checkup date, whether summer (n = 265) or not summer (n = 638). The not summer group was subdivided into spring (n = 235), autumn (n = 213) and winter (n = 190). RESULTS: Among the four seasons, the spring group showed the highest levels of plasma osmolality (306.1 ± 3.9 mOsm/L), urine specific gravity (1.0172 ± 0.0058) and prevalence rates of urine specific gravity ≥1.020 (34.0%). However, seasonal differences were clinically mild, and >90% of participants showed plasma osmolality ≥300 mOsm/L, indicating dehydration, in all four seasons. The summer group showed lower urine specific gravity levels (1.0150 ± 0.0062 vs. 1.0165 ± 0.0064, P < 0.001) and prevalence rates of urine specific gravity ≥1.020 (22.6% vs. 30.4%, P = 0.023) than did the not summer group. The summer season was associated with low urine specific gravity levels even after adjusting for the multiple linear regression model. CONCLUSION: Japanese elderly after overnight fast are more dehydrated during the spring rather than the summer. Geriatr Gerontol Int 2020; 20: 904-910.

The serum uric acid level in females may be a better indicator of metabolic syndrome and its components than in males in a Japanese population　.

BACKGROUND: Although the level of uric acid (UA) is higher in males, increased UA level in females was reported to be closely associated with prevalence of metabolic syndrome (Mets) leading to atherosclerotic cardiovascular disease (ASCVD). Few data exist regarding the gender diferences in relationship between the serum UA levels and cardo-metabolic risk in the Japanese population, which generally contains a lower proportion of obesity than Western populations. METHODS: This cross-sectional study was designed to investigate, by gender, the association between the serum UA level and abdominal obesity, and thereby cardio-metabolic risk i.e. presence of Mets and its components using a sample of 8567 apparently healthy subjects females: n = 3334, males: n = 5233 at the Health Planning Center of Nihon University Hospital between September 2015 and August 2016. RESULTS: Receiver operating characteristic analysis was performed to reveal the accuracy of serum UA level as a predictor of abdominal obesity based on the Japanese criteria of Mets (females vs. males: area under the curve, 0.751 vs 0.609). Furthermore, the serum UA level and proportion of abdominal obesity rose with increasing age in females; in males, however, these parameters did not change in parallel with age. Furthermore, the serum UA levels in females reflected a status of cardio-metabolic risk when compared with males in a multi-logistic regression analysis. It is particularly worth noting that in the above-mentioned multivariate logistic regression analysis, the odds ratio of hyperuricemia in females was generally 1.3-2.5 times higher than that in males. CONCLUSIONS: Compared with males, increased serum UA level in females might be involved in abdominal obesity and cardio-metabolic risk, possibly leading to the development of ASCVD even in a Japanese population. This may be due to gender differences affecting the development of abdominal obesity and changes in the serum UA levels with age. CLINICAL TRIAL REGISTRATION: UMIN (http://www.umin.ac.jp/) Study ID:　UMIN000035901retrospectively registered 1 March 2018.

Association of daily fish intake with serum non-high-density lipoprotein cholesterol levels and healthy lifestyle behaviours in apparently healthy males over the age of 50 years in Japanese: Implication for the anti-atherosclerotic effect of fish consumption.

BACKGROUND AND AIM: Higher fish consumption has been reported to be associated with a lower incidence of coronary artery disease (CAD). We hypothesized that higher fish intake may be associated with lower serum level of non-high-density lipoprotein cholesterol (non-HDL-C) levels, representing the entire dyslipidemia spectrum, and a healthy lifestyle. METHODS AND RESULTS: This cross-sectional study was conducted in a population of 1270 apparently healthy males over the age of 50 years without lipid-modifying therapy at the Health Planning Center of Nihon University Hospital between April and August 2018. The average number of days of fish intake per week was 2.6 ± 1.4. We performed analysis of variance using fish consumption as a categorical variable (0-1 day, 2-3 days, 4-5 days, or 6-7 days per week). The serum non-HDL-C levels in the 6-7 days fish intake group were significantly lower than those in the 0-1 and 2-3days fish intake groups. Furthermore, with increasing frequency of fish intake per week, the proportion of subjects with cigarette smoking decreased (p = 0.026), that of subjects engaging in habitual aerobic exercises increased (p = 0.034), and the sleep duration of the subjects increased (p < 0.0001). CONCLUSIONS: These results suggest that a high frequency of fish intake, that is a fish intake of 6-7 days per week, was associated with healthier lifestyle behaviours as well as lower non-HDL-C levels, and thus may represent a component of a healthy lifestyle associated with a lower risk of CAD in Japanese males over the age of 50. CLINICAL TRIAL REGISTRATION: UMIN (http://www.umin.ac.jp/). STUDY ID: UMIN000035899.

The effect and mechanism of action of capsaicin on gastric acid output.

BACKGROUND: Capsaicin has beneficial pharmacological properties, such as the ability to improve appetite and digestion. However, capsaicin has been reported to suppress gastric acid output, but to increase secretion; no consensus as to its effects on gastric acid output has been reached, and the underlying mechanisms remain to be elucidated. METHODS: Rat gastric lumen was perfused with capsaicin. Basal acid output and gastric acid secretion stimulated by vagal nerve activation and bethanecol, a muscarinic receptor agonist, were measured. After intravenous infusion of calcitonin gene-related peptide (CGRP), the measurements were repeated. The secretion of gastrin, somatostatin, and histamine was measured in isolated vascularly perfused rat stomach after vagal nerve and bethanecol stimulation, and under the influence of capsaicin. RESULTS: Capsaicin administration had no effect on basal gastric acid output, but inhibited acid secretion resulting from vagal stimulation. Capsaicin had no effect on acid secretion resulting from stimulation with bethanecol. Administration of high-dose CGRP inhibited basal acid output and gastric acid secretion from both vagal nerve and bethanecol stimulation. Low-dose CGRP inhibited gastric acid secretion because of vagal stimulation, but had no effect on basal secretion or acid secretion following stimulation with bethanecol. Capsaicin administration inhibited the stimulated gastrin and histamine secretion and reversed the suppression of somatostatin secretion mediated by vagal stimulation. However, capsaicin had no effect on stimulated gastrin secretion, suppression of somatostatin secretion, or stimulated histamine secretion because of bethanecol. CONCLUSIONS: Capsaicin inhibited gastric acid output, and the mechanism underlying this effect appears to involve vagal nerve inactivation.