Association Between the Appendicular Extracellular-to-Intracellular Water Ratio and All-Cause Mortality: A 10-Year Longitudinal Study.

The appendicular extracellular-to-intracellular water ratio (A-E/I) is a potential marker of skeletal muscle quality, reflecting the balance of water distribution between the extracellular and intracellular compartments of the appendicular limb regions. A-E/I has been increasingly used in recent studies; however, its association with adverse outcomes remains unclear. This study investigated the potential association between A-E/I and all-cause mortality. A prospective cohort study of 8 015 middle-aged and older adults (comprised of 4 755 women, aged 45-74 years) residing in a Japanese community was conducted. The baseline assessment was performed between 2010 and 2012, and the follow-up period lasted until July 2022. A-E/I and skeletal muscle mass were measured using segmental bioelectrical impedance spectroscopy. Handgrip strength (HGS) was measured using a Smedley-type dynamometer. Lifestyle, medical history, and physical activity were assessed by questionnaire and accelerometer. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) for each quartile (Q) of A-E/I were estimated using the multivariable Cox regression model. During a 10.5-year median follow-up, the mortality rates were 8.9 and 3.6 per 1 000 person-years for men (292 deaths) and women (174 deaths), respectively. A-E/I quartiles were positively associated with all-cause mortality in both sexes (men: Q1, HR: 1.0 [95% CI: reference], Q4, HR: 1.8 [1.1-2.9], ptrend < .05; women, Q4, HR: 2.2 [1.3-3.8], ptrend < .01). This association remained significant after further adjustment for skeletal muscle mass and HGS (ptrend < .05). Our findings suggest that A-E/I serves as an early predictive marker for mortality in middle-aged and older Japanese adults.

Dose-response relationship between daily step count and prevalence of sarcopenia: A cross-sectional study.

OBJECTIVES: Daily step counts are an easy-to-understand indicator of physical activity; however, there is limited evidence regarding the optimal daily step count to prevent sarcopenia. This study examined the dose-response relationship between daily step count and the prevalence of sarcopenia and explored the optimal dose. DESIGN: Cross-sectional study. SETTING AND PARTICIPANTS: The study included 7949 community-dwelling middle-aged and older adults (aged 45-74 years) from Japan. MEASUREMENTS: Skeletal muscle mass (SMM) was assessed using bioelectrical impedance spectroscopy, and muscle strength was quantified through handgrip strength (HGS) measurement. Participants who exhibited both low HGS (men: <28 kg, women: <18 kg) and low SMM (lowest quartile in each sex-specific category) were defined as having sarcopenia. Daily step counts were measured for 10 days using a waist-mounted accelerometer. To examine the association between daily step count and sarcopenia, a multivariate logistic regression analysis was performed, adjusting for potential confounding factors such as age, sex, body mass index, smoking status, alcohol consumption, protein intake, and medical history. The odds ratios (ORs) and confidence intervals (CIs) were calculated based on the daily step counts categorized into quartiles (Q1-Q4). Finally, a restricted cubic spline curve was fitted to further investigate the dose-response relationship between daily step count and sarcopenia. RESULTS: The prevalence of sarcopenia in the overall participants was 3.3 % (259/7949 participants), with a mean daily step count of 7292 ± 2966 steps. Expressed in quartiles, the mean daily step counts were 3873 ± 935 steps in Q1, 6025 ± 503 steps in Q2, 7942 ± 624 steps in Q3, and 11,328 ± 1912 steps in Q4. The prevalence of sarcopenia in each quartile of daily step count was 4.7 % (93/1987 participants) in Q1, 3.4 % (68/1987 participants) in Q2, 2.7 % (53/1988 participants) in Q3, and 2.3 % (45/1987 participants) in Q4. The ORs and 95 % CIs adjusted for covariates demonstrated a statistically significant inverse association between daily step count and sarcopenia prevalence (P for trend <0.01), as follows: Q1, reference; Q2, 0.79 (95 % CI: 0.55-1.11); Q3, 0.71 (95 % CI: 0.49-1.03); Q4, 0.61 (95 % CI: 0.41-0.90). The restricted cubic spline curve indicated that the ORs leveled off at approximately 8000 steps per day, and no statistically significant decrease in ORs was observed for daily step counts above this threshold. CONCLUSIONS: The study found a significant inverse association between daily step count and the prevalence of sarcopenia, with the association plateauing when the daily step count exceeded approximately 8000 steps. These findings suggest that 8000 steps per day may be the optimal dose to prevent sarcopenia. Further intervention and longitudinal studies are needed to validate the results.

Association of appendicular extracellular-to-intracellular water ratio with age, muscle strength, and physical activity in 8,018 community-dwelling middle-aged and older adults.

BACKGROUND: The appendicular extracellular-to-intracellular water ratio (Ap ECW/ICW) has recently gained attention as a non-invasive measurable marker of muscle quality. However, there is a lack of basic evidence regarding age-related changes, sex differences, contribution to muscle strength independent of skeletal muscle mass (SMM), and potential improvement through physical activity (PA) in Ap ECW/ICW. METHODS: This cross-sectional study enrolled 8,018 middle-aged and older Japanese individuals (aged 45-75 years). The Ap ECW/ICW and SMM were measured using segmental bioelectrical impedance spectroscopy. Muscle strength was evaluated by measuring the handgrip strength (HGS) with a dynamometer, and the PA level (PAL) was measured with an accelerometer. We performed a linear regression analysis of the associations of the Ap ECW/ICW with age, HGS, and PAL. RESULTS: The Ap ECW/ICW increased by 0.019 for men and 0.014 for women per 5-year increase in age (p < 0.001), and the age-related increase was greater in men than in women (p for interaction <0.001). The Ap ECW/ICW was more strongly associated with the HGS than with the SMM in both men and women (p < 0.001). PAL showed a significant inverse association with the Ap ECW/ICW in both men and women (p < 0.001). CONCLUSIONS: Ap ECW/ICW is higher with age, and it varies by sex. The Ap ECW/ICW may reflect muscle strength more than the SMM, suggesting that the Ap ECW/ICW may be improved by PA. The findings from this study may provide a framework for further Ap ECW/ICW research.

Epigenome-Wide Association Study Identified VTI1A DNA Methylation Associated With Accelerometer-Assessed Physical Activity.

INTRODUCTION: Health benefits of physical activity (PA) may be mediated by DNA methylation alterations. The purpose of the current study was to comprehensively identify CpG sites whose methylation levels were associated with accelerometer-assessed total PA in a general Japanese population. METHODS: The study participants were from the baseline survey of Saga Japan Multi-institutional Collaborative Cohort. PA was objectively measured by a single-axis accelerometer for 7 d. We used a two-stage strategy. In the discovery stage, we performed a meta-analysis of two epigenome-wide association studies of total PA in 898 individuals (a combination of random sample ( n = 507) and case-control study sample ( n = 391)). Peripheral blood DNA methylation levels were measured using Infinium EPIC or HM450 arrays. In the replication stage, we subsequently examined whether CpG sites significantly associated ( P < 1 × 10 -5 ) with total PA were replicated in another sample ( n = 1711), in which methylation levels were measured by pyrosequencing. A multiple linear regression was performed to determine the cross-sectional association between total PA and methylation levels with adjustment for potential confounders, including body mass index. A fixed-effects model was used in the meta-analysis. Correlations between total PA-associated DNA methylation and several inflammatory markers, such as high-sensitivity C-reactive protein, were also conducted. RESULTS: In the meta-analysis, nine CpG sites were significantly associated with total PA ( P < 1 × 10 -5 ). Among the nine sites, one site cg07030336 (annotated to VTI1A/ZDHHC6 gene) was successfully replicated ( P = 0.009). CONCLUSIONS: The current study showed that greater accelerometer-assessed total PA was associated with higher DNA methylation levels at cg07030336 ( VTI1A/ZDHHC6 ) in the general population. In addition, we found a divergent relationship between the methylation levels at cg07030336 and several inflammatory biomarkers.

Sedentary time, physical activity, and serum SPARC in a middle-aged population.

The influence of habitual physical activity (PA) on the circulating levels of secreted protein acidic and rich in cysteine (SPARC) remains unclear. The purpose of the current study was to clarify the effects of sedentary time, light-intensity PA (LPA), and moderate- to vigorous-intensity PA (MVPA) on the serum SPARC in a general middle-aged population. The current study is a cross-sectional study of 4,000 men and 6,040 women (40-69 years). Sedentary time, LPA, and MVPA were objectively measured by an accelerometer. The serum SPARC concentration was measured by enzyme-linked immunosorbent assay. Using an isotemporal substitution model, cross-sectional associations of replacing sedentary time with either LPA or MVPA on serum SPARC levels were analysed according to sex. Interactions with subject characteristics, such as the body mass index (BMI), smoking, and alcohol consumption, were also examined. In men, replacing 60 min of sedentary time with 60 min of MVPA was significantly associated with 23 ng/mL lower serum SPARC levels (confidence interval: -43, -2) after adjusting for confounders, including the BMI (P = 0.028). A significant interaction between replacing sedentary behaviour with LPA and the BMI on SPARC was detected in women (P = 0.029), although the stratified associations for each BMI level (<25 or ≥25 kg/m2) did not reach significance. The current study suggests that replacing sedentary time with MVPA is associated with reduced serum SPARC levels in middle-aged men, but not in women. In addition, a potential interaction between LPA and the BMI on SPARC was also found in women.Highlights An isotemporal substitution analysis showed that replacing sedentary behaviour with moderate- to vigorous-intensity physical activity (MVPA) is associated with decreased serum SPARC levels in men.Such an inverse association between replacing sedentary behaviour with MVPA and the SPARC levels was not observed in women.A potential interaction between replacing sedentary behaviour with light-intensity PA and the body mass index on the serum SPARC levels was also found in women.

Association between habitual coffee consumption and skeletal muscle mass in middle-aged and older Japanese people.

AIMS: Coffee consumption has been suggested, in animal studies, to inhibit the progression of sarcopenia, possibly through its anti-inflammatory effects; however, few studies have been carried out in humans. We aimed to examine whether coffee consumption was related to indicators of sarcopenia in a Japanese population, and whether the association was mediated by reduced inflammation. METHODS: This study was a cross-sectional design. Participants were community residents (n = 6369) aged 45-74 years. We measured skeletal muscle mass index (SMI; kg/m2 ) by a bioelectrical impedance method, and grip strength with a Smedley-type dynamometer. Habitual coffee consumption was assessed by a self-administered questionnaire. Serum high-sensitivity C-reactive protein was measured as an inflammatory marker. The association between habitual coffee consumption and SMI or grip strength was analyzed with a linear regression model adjusted for covariates. RESULTS: A significant positive association was found between coffee consumption and SMI (men: ß = 0.023; Ptrend  = 0.004, women: ß = 0.011; Ptrend  = 0.012). Further adjustment for high-sensitivity C-reactive protein did not materially alter the results (men: ß = 0.023; Ptrend  = 0.005, women: ß = 0.009; Ptrend  = 0.024). The relationship between coffee consumption and grip strength did not reach statistical significance; however, a positive trend was observed (men: ß = 0.208; Ptrend  = 0.085, women: ß = 0.092; Ptrend  = 0.167). CONCLUSIONS: We found that coffee consumption was positively associated with SMI independently of inflammation in middle-aged and older Japanese people. Reduced inflammation by coffee does not seem to be an important mediator, and further investigations are required to explore the mechanisms of this association. Geriatr Gerontol Int 2021; 21: 950-958.

Perceived stress, depressive symptoms, and cortisol-to-cortisone ratio in spot urine in 6878 older adults.

BACKGROUND: Late life depression and perceived stress could influence disease pathways via reduced 11ß-HSD2 activity, particularly given suggestions that reduced 11ß-HSD2 activity, which is reflected in the cortisol-to-cortisone ratio, is a risk factor of disease. To date, however, examination of the relationship between the cortisol-to-cortisone ratio and perceived stress or depressive symptoms is insufficient. METHODS: We examined the cross-sectional association of the cortisol-to-cortisone ratio with perceived stress and depressive symptoms, and analyzed whether cortisol levels modify this association, in 6878 participants aged 45-74 years. Cortisol and cortisone in spot urine were measured using liquid chromatography-mass spectrometry. Perceived stress during the past year was measured using a self-reported questionnaire. Depressive symptoms were evaluated using the Zung Self-Rating Depression Scale. Analyses were performed with adjustment for age, sex, lifestyle factors (smoking habit, alcohol consumption, physical activity, and sleeping hours), and physical health factors (body mass index [kg/m2] and medical history [diabetes, hypertension, and medication for hyperlipidemia or corticosteroids]). RESULTS: Cortisol-to-cortisone ratio and cortisol were positively associated with perceived stress (% change: 2.33, Ptrend = 0.003; and 4.74, Ptrend = 0.001, respectively), but were not significantly associated with depressive symptoms. Further, the relationship between cortisol-to-cortisone ratio and perceived stress was modified by cortisol level and sex: the positive association between perceived stress and the cortisol-to-cortisone ratio was more evident in subjects with lower cortisol levels (Pinteraction = 0.009) and in men (Pinteraction = 0.026). CONCLUSIONS: These findings suggest that the cortisol-to-cortisone ratio in spot urine may be a useful marker for non-acute perceived stress in daily life against a possible background of reduced 11ß-HSD2 in older adults.

The interaction between mitochondrial haplogroups (M7a/D) and physical activity on adiponectin in a Japanese population.

Mitochondrial haplogroups F, A, and M7a are associated with increased risks of lifestyle diseases, while haplogroups N9 and D are associated with decreased risks of lifestyle diseases or with longevity. The current study determined the existence of interactions between 5 selected haplogroups and physical activity (PA) on total and high-molecular-weight (HMW) adiponectin in 3,994 men and 6,014 women. The interactions between haplogroups (M7a/D) and PA on adiponectin were significant in men (total and HMW: P-interaction = 0.041 and 0.011). The positive association of PA with adiponectin in men carrying haplogroup M7a is attenuated in comparison to men carrying haplogroup D.

Habitual Light-intensity Physical Activity and ASC Methylation in a Middle-aged Population.

Apoptosis-associated, speck-like protein containing a caspase recruitment domain (ASC) plays an important role in inflammatory cytokine synthesis in peripheral blood mononuclear cells (PBMCs), and the expression of ASC is suppressed by increased methylation of its CpG sites. The current study investigated the longitudinal association of replacing sedentary time with light-intensity physical activity (LPA) or moderate to vigorous-intensity physical activity (MVPA) on the ASC methylation in middle-aged people. We investigated 1 238 individuals who participated in baseline and 5-year follow-up surveys of a population-based cohort study. Sedentary, LPA and MVPA time were objectively measured using accelerometers. ASC methylation in PBMCs was measured by pyrosequencing. Using a multiple linear regression and employing an isotemporal substitution model, the longitudinal associations of changes in the sedentary time, LPA and MVPA on the changes in the ASC methylation were analyzed after adjusting for potential confounders. Substituting 60 min per day of LPA for sedentary time was associated with 1.17 times (95% confidence interval 1.07, 1.27) higher ASC methylation levels (mean of 7 CpG sites, P<0.001). However, such effects were not seen for MVPA. These results suggest that substituting LPA for sedentary time may be linked with increased (favorable) ASC methylation as a potential biomarker of systemic inflammation.

Intensity-Specific and Modified Effects of Physical Activity on Serum Adiponectin in a Middle-Aged Population.

CONTEXT: The effects of intensity-specific physical activity (PA) and its interaction with other lifestyle factors on serum adiponectin are currently unclear. OBJECTIVE: To investigate the effects of replacing sedentary time with either light-intensity PA (LPA) or moderate- to vigorous-intensity PA (MVPA) on total and high-molecular-weight (HMW) adiponectin and to examine interactions with smoking, alcohol drinking, coffee consumption, and menopausal status in a general population. DESIGN/SETTING: Cross-sectional study of 4013 men and 6050 women (40 to 69 years of age). MAIN OUTCOME MEASURES: The associations of replacing sedentary time with LPA or MVPA on total and HMW adiponectin were analyzed using an isotemporal substitution model. RESULTS: In men, reallocating 60 minutes of sedentary time to 60 minutes of LPA was associated with 9% and 13% higher total and HMW adiponectin levels even after adjusting for confounders, although such associations were not observed for MVPA. A similar pattern of results was also seen in women. The effect of replacing sedentary time with LPA on adiponectin was clearer in middle/high coffee consumers than in low coffee consumers among women. Although increasing the effect of replacing sedentary time with MVPA on adiponectin was clearer in former/current smokers than in never smokers among men, the replacement effect for MVPA on total adiponectin was clearer in premenopausal women than in postmenopausal women. CONCLUSIONS: Replacing sedentary time with LPA resulted in increased levels of total and HMW adiponectin. The replacement effects for LPA or MVPA were found to be multiply modified by smoking, coffee consumption, and menopausal status.

Influence of Single-Nucleotide Polymorphisms in PPAR-δ, PPAR-γ, and PRKAA2 on the Changes in Anthropometric Indices and Blood Measurements through Exercise-Centered Lifestyle Intervention in Japanese Middle-Aged Men.

The purpose of the current study was to examine the influence of single-nucleotide polymorphisms (SNPs) in the peroxisome proliferator-activated receptor-δ (PPAR-δ), PPAR-γ, and α2 isoforms of the catalytic subunit of AMP-activated protein kinase (PRKAA2) on the extent of changes in anthropometric indices and blood measurements through exercise-centered lifestyle intervention in middle-aged men. A total of 109 Japanese middle-aged male subjects (47.0 ± 0.4 years) participated in the baseline health checkup, 6-month exercise-centered lifestyle intervention, and second checkup conducted several months after the subject completed the intervention. The body mass index (BMI), waist circumference, and clinical measurements, including hemoglobin Alc (HbA1c), triglyceride (TG), alanine aminotransferase (ALT), and γ-glutamyl-transpeptidase (γ-GTP), were measured at the baseline and second checkup. The three SNPs of PPAR-δ A/G (rs2267668), PPAR-γ C/G (rs1801282), and PRKAA2 A/G (rs1418442) were determined. Blunted responses in the reduction in the BMI and waist circumference were observed in A/A carriers of PPAR-δ SNP compared with G allele carriers (all p < 0.05). The A/A carriers also displayed less-marked improvements in HbA1c, TG, ALT, and γ-GTP (all p < 0.05). The current results suggest that A/A carriers of PPAR-δ SNP (rs2267668) may enjoy fewer beneficial effects of exercise-centered lifestyle intervention on anthropometric indices and blood measurements.

Coping strategy and social support modify the association between perceived stress and C-reactive protein: a longitudinal study of healthy men and women.

Inconsistent associations have been reported between perceived stress and C-reactive protein (CRP), a marker of systemic inflammation. We previously observed a male-specific inverse relationship between perceived stress and CRP in a cross-sectional study. In the present study, we examined the longitudinal association between changes in perceived stress and CRP, and further analyzed whether changes in coping strategies and social support modify this association. This study included 8454 participants in both a baseline survey and a follow-up survey 5 years later. Psychosocial measures (i.e. perceived stress, coping strategies, and social support) and CRP concentrations were measured by identical means in both surveys. Consistent with our previous findings, increased perceived stress was significantly associated with lower CRP in men (ptrend = .037), but not in women. Increased "emotional expression," a coping strategy, was also associated with lower CRP in women (ptrend = .024). Furthermore, interactions between perceived stress and a coping strategy (positive reappraisal) or social support on CRP were found in men (pinteraction = .007 and .038, respectively); the above inverse association between stress and CRP was not detected for participants with diminished positive reappraisal or social support. In conclusion, increases in perceived stress during a 5-year period were associated with decreases in CRP among healthy men, and the observed association was possibly modified by coping strategy or social support.

Perceived Stress, Depressive Symptoms, and Oxidative DNA Damage.

OBJECTIVE: Psychosocial stress may influence the risk of disease through its association with oxidative DNA damage. We examined whether perceived stress and depressive symptoms were associated with urinary excretion of 8-hydroxydeoxyguanosine (8-OHdG), with mutual interaction on 8-OHdG. METHODS: This cross-sectional study included 6517 individuals aged 45 to 74 years who participated, between 2010 and 2012, in a follow-up survey of an ongoing cohort study. Perceived stress during the past year was measured using a self-report questionnaire. Depressive symptoms were evaluated using the Zung Self-Rating Depression Scale. Urinary 8-OHdG concentrations were measured using a column switching high-pressure liquid chromatography system coupled to an electrochemical detector. RESULTS: Higher perceived stress was significantly associated with higher 8-OHdG (2.1% increase per one-category increase of stress; ptrend = .025), even after adjusting for sex, age, supplement use, psychosocial factors, psychotropic medication use, smoking, and body mass index. This association was modestly attenuated after further adjustment for physical activity, suggesting possible mediation or confounding by this factor. Depressive symptoms were not significantly associated with 8-OHdG. No significant interaction was detected between perceived stress and depressive symptoms on 8-OHdG. CONCLUSIONS: In a general Japanese population, we found a weak positive association between perceived stress and urinary excretion of 8-OHdG, whereas no association was observed between depressive symptoms and 8-OHdG. Further studies are needed to examine whether the association between perceived stress and 8-OHdG is modified by depressive symptoms.

Intensity-specific effect of physical activity on urinary levels of 8-hydroxydeoxyguanosine in middle-aged Japanese.

Physical activity (PA) is recommended to both promote and maintain health and prevent cancer by improving the body's DNA repair system, which is considered a mechanism of cancer prevention. However, associations between PA and urinary levels of 8-hydroxydeoxyguanosine (8-OH-dG), which reflects DNA damage, are unclear. This cross-sectional study included 2370 men and 4052 women aged 45-74 years enrolled between 2010 and 2012. Habitual PA was assessed by single-axis accelerometer and urinary 8-OH-dG levels by automated HPLC. Multiple linear regression analysis was used to examine the relationship between log-transformed urinary 8-OH-dG and total PA (TPA) and PA of moderate/vigorous intensity (MVPA; ≥3 metabolic equivalents), with adjustment for age, body mass index, energy intake, alcohol consumption, smoking status, daily coffee drinking, menopause status (in women), and TPA (for MVPA). On multivariate adjustment, urinary 8-OH-dG levels were inversely correlated with TPA (ß = -0.020, P < 0.01) in women, and this correlation was not changed by PA intensity. Conversely, urinary 8-OH-dG levels were inversely correlated with MVPA (ß = -0.022, P < 0.05) in men, although the correlation with TPA was non-significant. This inverse correlation was clearer in current smokers than in never or former smokers, although the interaction between smoking status and MVPA on urinary 8-OH-dG levels was non-significant. In conclusion, greater TPA in women and greater MVPA in men were correlated with reduction in urinary 8-OH-dG, suggesting sex-specific effects of MVPA and TPA on protection from oxidative DNA damage. Increasing PA may mediate reduction in oxidative stress.

Dietary patterns and serum gamma-glutamyl transferase in Japanese men and women.

BACKGROUND: Although specific foods and nutrients have been examined as potential determinants of serum gamma-glutamyl transferase (GGT) concentrations, the relationship between dietary patterns and GGT remains unknown. The present cross-sectional study aimed to determine relationships between dietary patterns and GGT concentrations, and the effects of lifestyle factors on GGT. METHODS: Relationships between dietary patterns and GGT were analyzed in 9803 Japanese individuals (3723 men and 6080 women age 40-69 years) without a history of liver diseases or elevated serum aminotransferase. We examined major dietary patterns by factor analysis of 46 items determined from a validated, short food frequency questionnaire. RESULTS: We defined dietary patterns as healthy, Western, seafood, bread, and dessert. The healthy pattern was inversely related to GGT in men (odds ratio [OR] for highest vs lowest quartile, 0.72; 95% confidence interval [CI], 0.57-0.92; P < 0.01 for trend) and women (OR 0.82; 95% CI, 0.66-1.0; P = 0.05 for trend), whereas the seafood pattern was positively related to GGT in men (OR 1.27; 95% CI, 1.01-1.61; P = 0.03 for trend) and women (OR 1.21; 95% CI, 0.98-1.49; P = 0.05 for trend). Male-specific inverse associations with GGT were found for bread and dessert patterns (OR 0.63; 95% CI, 0.50-0.80 and OR 0.53; 95% CI, 0.41-0.68, respectively; P < 0.01 for both trends). Seafood or bread patterns and alcohol consumption significantly interacted with GGT in men (P = 0.03 and <0.01 for interaction, respectively) and between the dessert pattern and body mass index or smoking habit in women (P = 0.03 and <0.01, respectively, for interaction). CONCLUSIONS: Dietary patterns may be important determinants of GGT, and their possible clinical implications warrant further investigation.

Association between the PPARGC1A polymorphism and aerobic capacity in Japanese middle-aged men.

OBJECTIVE: A lower frequency for the peroxisome proliferator-activated receptor γ coactivator 1α (PPARGC1A) Ser482 allele has been reported in elite-level endurance athletes among Caucasians, although this gene polymorphism has not been found to be associated with aerobic capacity in German, Dutch or Chinese populations. The purpose of the current study was to examine the associations between the Gly482Ser polymorphism and aerobic fitness in 112 Japanese middle-aged men. METHODS: The PPARGC1A Gly482Ser polymorphism was identified according to a TaqMan(®) SNP genotyping assay. Habitual physical activity was objectively measured using an accelerometer. The lactate threshold (LT), an index of aerobic fitness, was measured based on a submaximal graded exercise test performed on an electric cycle ergometer. The association between the LT and the Gly482Ser polymorphism was assessed according to a multiple regression analysis and analysis of covariance, with adjustment for potential confounders (age, body mass index, cigarette smoking, physical activity level and regular exercise). RESULTS: A significant association was observed between the PPARGC1A Gly482Ser polymorphism and LT, as carriers of the Ser482 had higher LT values than the Gly482 carriers. CONCLUSION: The current results suggest that the PPARGC1A Ser482 allele is associated with a higher aerobic capacity in Japanese middle-aged men.

Perceived stress and coping strategies in relation to body mass index: cross-sectional study of 12,045 Japanese men and women.

BACKGROUND: Accumulated evidence suggests a weak positive relationship between psychosocial stress and body mass index (BMI), but little is known about stress coping strategies and BMI. OBJECTIVE: We aimed to examine if perceived stress and coping strategies are related to BMI, with any of their mutual interactions on BMI. METHODS: This cross-sectional study included 5,063 men and 6,982 women aged 40-69 years. A self-administered questionnaire ascertained perceived stress and 5 items of coping strategies (emotion expression, emotional support seeking, positive reappraisal, problem solving, and disengagement). Analyses were performed by gender with adjustment for age, socioeconomic status, and lifestyle factors. RESULTS: No significant associations were detected between perceived stress and BMI in either men (P(trend) = 0.09) or women (P(trend) = 0.58). In men, however, 'disengagement' showed an inverse association with BMI (P(trend) < 0.001), and 'positive reappraisal' and 'problem solving' revealed a positive association with BMI (P(trend) = 0.04 and 0.007, respectively) even after controlling for perceived stress. A possible interaction between perceived stress and 'disengagement' on BMI was found in men (P(interaction) = 0.027); the inverse association between 'disengagement' and BMI was more evident in higher levels of stress (ß = -0.13, P(trend) = 0.21 in low; ß = -0.22, P(trend) = 0.01 in medium; and ß = -0.24, P(trend) = 0.06 in high). In men, 'disengagement' was inversely associated with overweight/obesity (odds ratio 0.79, 95% confidential interval 0.67-0.95), and "positive reappraisal" was positively associated with it (1.25, 1.02-1.54). CONCLUSIONS: Coping strategies may have an important role in developing overweight/obesity, particularly in men.

Factors associated with non-participation in a face-to-face second survey conducted 5 years after the baseline survey.

BACKGROUND: Non-participation in second surveys is reported to be associated with certain baseline characteristics; however, such data are unavailable for Japanese populations. Although disease incidence during follow-up might influence participation, few reports have addressed this possibility. This study sought to identify factors associated with non-participation in a second survey of a population-based cohort, and to evaluate the influence of self-reported disease incidence on non-participation. METHODS: After excluding participants who left the area (n = 423), died (n = 163), and withdrew from the study (n = 9) among 12 078 participants in a baseline survey for the Japan Multi-Institutional Collaborative Cohort Study in the Saga region between 2005 and 2007, 11 483 people were invited by mail to participate in a face-to-face second survey between 2010 and 2012. The 5-year clinical health history of non-participants was assessed by mail or telephone. Baseline characteristics and self-reported clinical outcomes of non-participants were compared with those of participants. RESULTS: Among 11 483 people, 8454 (73.6%) participated in the second survey, and 2608 out of 3029 non-participants answered mail or telephone health surveys. Female sex, youngest and oldest ages, lower education, lower occupational class, current smoking, lower physical activity level, shorter sleep time, obesity, and constipation were associated with non-participation. Light drinking (0.1-22.9 g ethanol/day) was associated with participation. Non-participants reported a significantly higher incidence of cancer and a significantly lower proportion of hypertension compared with participants. CONCLUSIONS: Both baseline characteristics and disease incidence during the follow-up period had significant associations with non-participation in the face-to-face second survey.

Polymorphisms of genes involved in lipid metabolism and risk of chronic kidney disease in Japanese - cross-sectional data from the J-MICC study.

BACKGROUND: Chronic kidney disease (CKD) is known to be one of the causes of cardiovascular disease and end-stage renal disease. Among the several treatable risk factors of CKD, that of dyslipidemia is relatively controversial. To clarify the association of polymorphisms in genes involved in lipid metabolism with the risk of CKD in the Japanese population, we used cross-sectional data from the Japan Multi-Institutional Collaborative Cohort (J-MICC) Study. METHODS: A total of 3,268 men and women, aged 35-69 years, were selected from J-MICC Study participants for inclusion in this study. Twenty-eight candidate single nucleotide polymorphisms (SNPs) were selected in 17 genes associated with the risk of lipid metabolism disorders, and genotyping of the subjects was conducted using the multiplex PCR-based invader assay. The prevalence of CKD was determined for stages 3-5 (defined as estimated glomerular filtration rate <60 ml/min/1.73 m2). RESULTS: Logistic regression analysis revealed that SNPs APOA5 T - 1131C (rs662799), APOA5 T1259C (rs2266788), TOMM40 A/G (rs157580), and CETP TaqIB (rs708272) were significantly associated with CKD risk in those individuals genotyped, with age- and sex-adjusted odds ratios (ORs) per minor allele (and 95% confidence intervals (CIs)) of OR 1.22 (95% CI: 1.06-1.39), 1.19 (1.03-1.37), 1.27 (1.12-1.45), and 0.81 (0.71-0.92), respectively. Analysis of the gene-environment interaction revealed that body mass index (BMI) was a significant effect modifier for APOA5 T - 1131C (rs662799) and a marginally significant effect modifier for APOA5 T/C (rs2266788), with the interaction between BMI ≥30 and individuals with at least one minor allele of each genotype of OR 10.43 (95% CI: 1.29-84.19) and 3.36 (0.87-13.01), respectively. CONCLUSIONS: Four polymorphisms in APOA5, TOMM40, and CETP were shown to be significantly associated with CKD risk, and a significant interaction between the two APOA5 SNPs and BMI on CKD risk was also demonstrated. This suggests the future possibility of personalized risk estimation for this life-limiting disease.