Regular exercise reduces the risk of all-cause mortality in socially isolated older adults: the Otassha Study.

Introduction: Social isolation is associated with increased mortality risk. On the other hand, some older adults prefer to be alone. Additionally, predictors of isolation are mostly unchanged across interventions. Therefore, knowledge of how to prevent negative health outcomes in isolation would be beneficial. One of the factors that reduces the risk of mortality is regular exercise. However, to date, no studies to our knowledge have examined whether regular exercise reduces mortality among socially isolated individuals. This study aimed to determine the effects of the combination of social isolation and regular exercise on mortality among community-dwelling older adults. Methods: This prospective cohort study was part of the larger Otassha Study of community-dwelling older adults living in Itabashi Ward, Tokyo, Japan. In October 2012, 835 individuals (males = 350, females = 485; mean age 73.1 years) completed a comprehensive baseline health survey. Individuals were considered socially isolated if their frequency of interactions with others averaged less than once per week. Regular exercise was defined as exercise performed at least twice a week. The participants were assigned to one of the following four groups: (1) not isolated with regular exercise, (2) not isolated without regular exercise, (3) isolated with regular exercise, and (4) isolated without regular exercise. All-cause mortality information was obtained from the ward office database. Follow-ups were conducted until 1 November 2020. A Cox proportional regression analysis was performed. Results: A final analysis was performed on a complete dataset of 735 participants (males = 303, females = 432; mean age 72.9 years). A total of 132 (18.0%), 426 (58.0%), 27 (3.7%), and 150 (20.4%) participants were assigned to groups 1, 2, 3, and 4, respectively. The mortality rates in groups 1, 2, 3, and 4 were 6.1%, 9.2%, 7.4%, and 19.3%, respectively. Compared with group 1, isolated individuals who did not perform regular exercise had a significantly higher mortality rate [adjusted hazard ratio (aHR), 2.48; 95% confidence interval (CI), 1.12-5.52]. However, no significant association was noted in isolated individuals who performed regular exercise (aHR, 1.25; 95% CI, 0.26-5.91). Conclusion: Regular exercise was associated with a decrease in mortality risk, regardless of social isolation status. Thus, our results indicate that encouraging isolated older adults to exercise regularly may reduce their negative health outcomes.

Knee Extensor Muscle Strength Associated with the Onset of Depression in Older Japanese Women: The Otassha Study.

We examined whether knee extensor muscle strength can predict the onset of depressive symptoms in older Japanese women living in Tokyo. A baseline comprehensive geriatric examination was conducted to evaluate isometric knee extensor muscle strength and depressive symptoms (using Geriatric Depression Scale [GDS]) in 2017-2019. A free of neurological disease participants received a series of follow-up examinations following an initial evaluation. A GDS score of ≥5 during follow-up marked the onset of depressive symptoms. A logistic regression model was established after adjustment of baseline GDS score for variables including age, body mass index, smoking, alcohol consumption, comorbidities, working status, hobbies, volunteering, years of education, and dietary variety. Of the 1845 recruited individuals, 1409 were eligible to be targeted for follow-up. Among them, 768 women provided two-year follow-up data and contributed the final analysis. After covariate adjustments, the odds ratios (95% confidence interval) for depressive symptoms were 0.68 (0.39, 1.20) and 0.48 (0.26, 0.91) for the middle and highest tertiles of muscle strength, respectively, using the lowest tertile as reference. A dose-response association between muscle strength and depression (p = 0.022) was identified. This study suggests an inverse dose-response relationship between knee extensor muscle strength and the onset of depressive symptoms in older Japanese women.

Psychotic experiences and dissociation in adolescents: Within-person analysis in the Tokyo teen cohort.

Although many cross-sectional studies showed that psychotic experiences (PEs) and dissociation were closely related, the longitudinal association between them remains unknown. Therefore, the aim of the current study was to examine the longitudinal association of these two symptoms throughout adolescence, under the hypothesis that these two symptoms are bidirectionally associated. Data were obtained from a population-based cohort, the Tokyo Teen Cohort study (TTC; N = 3171). PEs and dissociation were assessed at 10, 12, 14, and 16 years of age. PEs were assessed using a total score from five-item self-report questionnaires derived from the Diagnostic Interview Schedule for Children (DISC-C). Dissociation was assessed using subscale scores of the Child Behavior Checklist (CBCL) completed by primary caregivers. We examined the longitudinal relationship between PEs and dissociation using the random intercept cross-lagged panel model (RI-CLPM). The within-person component of the RI-CLPM revealed no significant cross-lagged effect of dissociation on PEs at any time point. On the other hand, there was a significant (p < 0.05) association between PEs at age 14 and dissociation at age 16 (ß = 0.106, 95 % CI 0.047-0.165). The between-person component revealed a significant time-invariant relationship between the two symptoms (ß = 0.324, 95 % CI 0.239-0.410). The longitudinal relationship between PEs and dissociation was limited at the within-person level, whereas the between-person correlation was significant. The only significant longitudinal pathway was from PEs to dissociation, suggesting that PEs may be a predictor of dissociation in mid-adolescence.

Former Olympians had remained on high bone mineral density for a long period: Consecutive checkup of the 1964 Tokyo Olympic Japanese contestants for over 50 years.

INTRODUCTION: We performed consecutive checkups of the 1964 Tokyo Olympic contestants every 4 years for 50 years. This study evaluated bone mineral density (BMD) and its related factors in former Tokyo Olympic athletes. OBJECTIVES: The study population comprised 181 former Olympians (141 men and 40 women) who had undergone BMD measurement in at least one of the four checkups performed every 4 years since 2005. The mean age of the 104 subjects who participated in the last checkup in 2016 was 76.1 years for men and 74.0 years for women. METHODS: Health-related information regarding medical history, regular physical activity, alcohol consumption, and smoking was obtained using questionnaires. The areal BMD of the total body was measured using dual-energy X-ray absorptiometry (DXA). The relationship between BMD and anthropometric measurements, medical history, and health behaviors was examined. Furthermore, we assessed the influence of the mode and magnitude of weight-bearing and impact loading during athletic events during their active careers on BMD. RESULTS: The mean Z-scores of BMD of the total body, lumbar spine, pelvis, and upper and lower limbs were > 0 in both male and female subjects at each checkup. The subjects had a higher mean height and weight than the Japanese age- and sex-matched individuals. Furthermore, the subjects had higher grip strength than the age- and sex-matched individuals. BMD showed a positive correlation with body weight, lean body mass (LBM), muscle mass, and grip strength, with higher correlation coefficients found between BMD of the pelvis or lower limbs and LBM or muscle mass volume. When the association with current participation in sports activities was examined, male subjects who exercised weekly had significantly higher grip strength and greater muscle mass volume; however, no significant differences were observed among female subjects. After adjusting for age and LMB, BMD was significantly higher in both the lumbar spine and lower limbs of male subjects with relatively more impact loading in sports events during their active careers. CONCLUSION: The Tokyo Olympic contestants maintained a high muscle mass even at an older age, regardless of their medical history, which may be one of the reasons for their ability to maintain a high BMD.

Application of cultured epidermal autograft, JACE®, improves survival rate in extensive burns: A propensity score matching study using Tokyo registry data.

Cultured epidermal autograft, JACE®, was introduced into the Japanese national health insurance system in 2009 and has been used in more than 1000 cases of extensive burns. The aim of this study was to investigate whether the use of JACE® contributes to survival rate in extensive burns. In this study, 119 cases were selected from 3990 cases in Tokyo Burn Unit Association registry data from 2009 to 2023, excluding cases with less than 40% total body surface area, cases of deaths within 4 weeks and cases with unknown length of hospital stay. In total, 25 patients treated with JACE® were selected and matched with another 25 patients who did not receive JACE® using propensity score matching. The results showed that patients treated with JACE® had a significantly higher survival rate than did those who were not treated with JACE® at all time points between 6 and 9 weeks post-injury. In addition, there was no significant difference in length of hospital stay between the groups. These results suggest that the use of JACE® in patients with extensive burns contributes to patient survival and does not prolong hospital stay.

Combination of 2 test methods, single-picture optotype visual acuity chart and spot™ vision screener, in the eye health screening program for 3-year-old children in Tokyo: A retrospective, observational study.

To evaluate the usefulness of the Tokyo Metropolitan Government's Eye Health Screening Program for 3-year-old children, which combines the Single-Picture Optotype Visual Acuity Chart (SPVAC) and Spot™ Vision Screener (SVS) tests. This was a retrospective, observational, matched study. Patients who underwent the eye health screening program and had abnormalities were classified into 3 groups according to the outcomes of the SPVAC (SPVAC-passed, SPVAC-P; SPVAC-failed, SPVAC-F) and SVS (SVS-passed, SVS-P; SVS-failed, SVS-F) tests as follows: SPVAC-P/SVS-F, SPVAC-F/SVS-P, and SPVAC-F/SVS-F. We evaluated the age at examination, SPVAC and SVS test success rates, and SVS refractive power. Additionally, the rates of refractive error, amblyopia, and strabismus were compared among the 3 groups. The SPVAC-P/SVS-F, SPVAC-F/SVS-P, and SPVAC-F/SVS-F groups comprised 158, 28, and 74 eyes, respectively. The mean age was 37.4 months. The success rates of the SPVAC and SVS tests were 69.8% and 96.2%, respectively. The mean SVS hyperopia value in the SPVAC-F/SVS-F group (2.71 ±â€…1.50 D) was significantly higher than that of the SPVAC-P/SVS-F group. The mean SVS astigmatism and myopia values were -2.21 diopter (D) ±â€…1.09 D and -3.40 ±â€…1.82 D, respectively; they did not differ significantly from that of the SPVAC-P/SVS-F group. Significant differences were observed in the refractive error, amblyopia, and strabismus rates among the 3 groups. Regarding disease determination, no significant difference was observed among participants who passed and failed the SPVAC test, regardless of the outcome of the other test. However, a significant difference was observed between those passing and failing the SVS tests. The SPVAC method used to screen 3-year-old children should be modified to commence at 42 months of age or be replaced with a single Landolt C test. The SVS test is useful for screening younger patients. Furthermore, the SVS test showed that the degree of hyperopia was higher in patients who did not pass the SPVAC test.

Clinical significance and normal reference value of serum creatinine to cystatin C ratio in children.

BACKGROUND & AIMS: Sarcopenia is a serious problem in adults and children. However, limited modalities are available for diagnosing pediatric sarcopenia. The serum creatinine to cystatin C ratio (Cre/CysC ratio) is a promising method for muscle quantification, although its clinical significance in the pediatric population is unknown. This study aimed to evaluate the relationship between the Cre/CysC ratio and physical performance. METHODS: This was a single-center retrospective study. Patients aged <15 years who had visited the University of Tokyo Hospital for measurements of serum creatinine and cystatin C levels, body height, and body weight were included. The patients were assigned according to their age (<2 or ≥2 years), and the relationship between the Cre/CysC ratio and physical performance at the time of measurement was analyzed. RESULTS: We included 266 patients, revealing a significant relationship between Cre/CysC ratio and physical performance in children aged ≥2 years (p < 0.001) but not in children aged <2 years (p = 0.42). The repeater-operator curve analysis of Cre/CysC to predict bedridden status showed good performance (the area under the curve was 0.82 (95% CI, 0.75-0.89)) and the cut-off value 0.44 had good accuracy (sensitivity 0.87, specificity 0.61). CONCLUSIONS: The Cre/CysC ratio was a significant marker of impaired physical performance, and a Cre/CysC ratio <0.44 accurately predicted bedridden status in children aged >2 years.

Wrestling injuries during the 2016 Rio and 2020 Tokyo Olympic Games.

OBJECTIVES: To evaluate and compare the injuries of Olympic wrestlers during the 2016 Rio and 2020 Tokyo Olympic Games held in August 2021 due to the COVID-19 pandemic. METHODS: In this descriptive epidemiological study, injury report forms were used to collect and analyse injury data during the competitions. RESULTS: During 410 matches in the Rio Olympic Games, 21 injuries were recorded among 346 wrestlers (112=women), a rate of 5.1 injuries/100 bouts and 6.1 injuries/100 athletes. During 322 matches in the Tokyo Olympic Games, 28 injuries were recorded among 287 wrestlers (96=women), with 8.7 injuries/100 bouts and 9.8 injuries/100 athletes. However, these apparent differences in injury rates between Tokyo and Rio were not statistically significant (injuries/bout: p=0.057, 95% CI: 0.31 to 1.02; injuries/athlete: p=0.087, 95% CI: 0.33 to 1.08). Mild injuries comprised the greatest proportion of injuries in both Olympic Games. Severe injuries accounted for 0%, 16.7% and 36.4% of injuries in Greco-Roman, Freestyle and Women's wrestling, respectively. CONCLUSION: Most wrestling injuries in the 2016 Rio and 2020 Tokyo Olympic Games were mild skin injuries in the head and face regions due to direct body contact during standing positions in the 1/8-final round of wrestling competitions. No critical injury was observed during the recent Olympic Games. Attention should be drawn to preventing upper limb joint dislocations as common severe injuries in both Olympic Games. While not statistically significant, the Tokyo Games, after the COVID-19 pandemic, witnessed a higher injury occurrence than the Rio Games.

The extracellular-to-total body water ratio reflects improvement in the activities of daily living in patients who experienced acute stroke.

OBJECTIVES: To determine the relationship between bioelectrical impedance analysis (BIA) parameters, including the extracellular water-to-total body water ratio (ECW/TBW), and the activities of daily living (ADL) improvement, in patients who experienced acute stroke. MATERIALS AND METHODS: This retrospective cohort study included 307 patients (mean age, 72 years; 39 % female) who experienced acute stroke and were admitted to the stroke unit of the Nippon Medical School Hospital (Bunkyo-ku, Tokyo, Japan) between April 2021 and March 2022. The Functional Independence Measure (FIM) was assessed at initial rehabilitation and discharge, and FIM effectiveness was calculated as ADL improvement in the participating acute care hospitals. BIA markers included the skeletal muscle mass index (SMI), phase angle (PhA), and ECW/TBW. Multiple linear regression models were used to estimate the relationship between the FIM effectiveness and each BIA marker. RESULTS: The mean (±SD) FIM effectiveness was 0.45 ± 0.36. The proportions of low SMI (male, <7.0 kg/m2; female, <5.7 kg/m2) and low PhA (male <5.36 degrees, female <3.85 degrees), were 48.9 % and 43.3 %, respectively. In addition, the proportions of of low (<0.36), normal (0.36-0.40), and high (>0.4) ECW/TBW ratios were 1.3 %, 78.5 %, and 20.2 %, respectively. After adjustments for demographic and clinical variables, low PhA, low ECW/TBW, and high ECW/TBW were all significantly associated with FIM effectiveness (P < 0.05), with ß coefficients of -0.126, -0.089, and -0.117, respectively. CONCLUSIONS: Low and High ECW/TBW and low PhA levels were negatively correlated with improvements in ADL. The ECW/TBW ratio may be an additional indicator of rehabilitation trainability in patients who experience acute stroke.

Electromagnetic field exposure monitoring of commercial 28-GHz band 5G base stations in Tokyo, Japan.

Fifth generation (5G) wireless communication is being rolled out around the world. In this work, the latest radio frequency electromagnetic field (EMF) exposure measurement results on commercial 28-GHz band 5G base stations (BSs) deployed in the urban area of Tokyo, Japan, are presented. The measurements were conducted under realistic traffic conditions with a 5G smartphone and using both omnidirectional and horn antennas. First and foremost, in all cases, the electric-field (E-field) intensity is much lower (<-38 dB) than the exposure limits. The E-field intensities for traffic-off cases do not show any significant difference between the two antennas with the maximum being 3.6 dB. For traffic-on cases, the omnidirectional antenna can undesirably capture the radio wave from the smartphone in some cases, resulting in a 7-13 dB higher E-field intensity than that using the horn antenna. We also present comparative results between 4G long term evolution BSs and sub-6-GHz band and 28-GHz band 5G BSs and provide recommendations on acquiring meaningful EMF exposure data. This work is a further step toward the standardization of the measurement method regarding quasi-millimeter/millimeter wave 5G BSs.

Monitoring the ventilation of living spaces to assess the risk of airborne transmission of infection using a novel Pocket CO2 Logger to track carbon dioxide concentrations in Tokyo.

We employed carbon dioxide (CO2) concentration monitoring using mobile devices to identify location-specific risks for airborne infection transmission. We lent a newly developed, portable Pocket CO2 Logger to 10 participants, to be carried at all times, for an average of 8 days. The participants recorded their location at any given time as cinema, gym, hall, home, hospital, other indoors, other outgoings, pub, restaurant, university, store, transportation, or workplace. Generalized linear mixed model was used for statistical analysis, with the objective variable set to the logarithm of CO2 concentration. Analysis was performed by assigning participant identification as the random effect and location as the fixed effect. The data were collected per participant (seven males, four females), resulting in a total of 12,253 records. Statistical analysis identified three relatively poorly ventilated locations (median values > 1,000 ppm) that contributed significantly (p < 0.0001) to CO2 concentrations: homes (1,316 ppm), halls (1,173 ppm), and gyms (1005ppm). In contrast, two locations were identified to contribute significantly (p < 0.0001) to CO2 concentrations but had relatively low average values (<1,000 ppm): workplaces (705 ppm) and stores (620 ppm). The Pocket CO2 Logger can be used to visualize airborne infectious transmission risk by location to help guide recommendation regarding infectious disease policies, such as restrictions on human flow and ventilation measures and guidelines. In the future, large-scale surveys are expected to utilize the global positioning system, Wi-Fi, or Bluetooth of an individual's smartphone to improve ease and accuracy.

Dose-response associations between physical activity and sedentary time with functional disability in older adults with or without frailty: a prospective cohort study.

Purpose: Evidence regarding the dose-response curve shapes of physical activity (PA) and sedentary time (ST) in older adults with functional disability (FD) is extremely limited. Moreover, these associations may differ depending on with/without frailty. We examined the dose-response associations between moderate-to-vigorous PA (MVPA) and ST with FD among older adults with/without frailty. Methods: We included 7,480 initially nondisabled adults (3,795 men and 3,685 women) aged 65-84 years in Ota City, Tokyo, Japan. MVPA and ST were evaluated using the International Physical Activity Questionnaire-Short Form. FD was prospectively identified using a nationally unified database of the long-term care insurance system. Frailty was determined using Check-List 15, validated against Fried's frailty criteria. Multivariate-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of MVPA and ST for FD were calculated, and dose-response curves were examined using restricted cubic splines. Results: During 3.6 years of follow-up, 1,001 (13.4%) participants had FD. Among all participants, compared with no MVPA, the HRs for FD reduced linearly up to approximately 2000 metabolic equivalents (METs)■min/week of MVPA, and the lowest HR (HR: 0.61, 95% CI: 0.51-0.74) was reached at around 3,000-4,000 METs■min/week. Although the shape of this association was consistent regardless of with/without frailty, the magnitude of the association tended to be stronger in frail older adults than in non-frail older adults. Compared with those for the median (300 min/day) of ST, the HRs for FD increased linearly as ST reached approximately 600 min/day or more, independent of MVPA, with a maximum HR of 1.31 (95% CI: 1.01-1.71) for 1,080 min/day among all participants. This association was more pronounced among non-frail older adults but not statistically significant among frail older adults. Conclusion: Higher MVPA levels consistently reduced the incidence of FD regardless of frailty in a significant inverse nonlinear dose-response manner. A significant positive nonlinear dose-response association between ST and FD risk was identified among non-frail older adults but not among frail older adults. Increasing MVPA and reducing prolonged ST are important for preventing FD among non-frail older adults. However, reducing ST alone may be insufficient; increasing MVPA, even if by only small increments, is highly recommended for frail older adults.

Preoperative difficulty factors in delayed laparoscopic cholecystectomy: Tokyo Guidelines 2018 surgical difficulty score analysis.

INTRODUCTION: Tokyo Guidelines 2018 (TG18) recommend early laparoscopic cholecystectomy (LC) for low-risk acute cholecystitis (AC); however, some patients undergo delayed LC (DLC) after conservative treatment. DLC, influenced by chronic inflammation, is a difficult procedure. Previous studies on LC difficulty lacked objective measures. Recently, TG18 introduced a novel 25 findings difficulty score, which objectively assesses intraoperative factors. The purpose of this study was to use the difficulty score proposed in TG18 to identify and investigate the predictors of preoperative high-difficulty cases of DLC for AC. METHODS: We retrospectively reviewed 100 patients with DLC after conservative AC treatment. The surgical difficulty of DLC was evaluated using a difficulty score. Based on previous studies, the highest scores in each category were categorized as grades A-C. RESULTS: The severity of AC was mild in 51 patients and moderate in 49. Surgical outcomes revealed a distribution of difficulty scores, with grade C indicating high difficulty, showing significant differences in operative time, blood loss, achieving a critical view of safety, bailout procedures, and postoperative hospital stay compared with grades A and B. Regarding the preoperative risk factors, multivariate analysis identified age >61 years (p = .008), body mass index >27.0 kg/m2 (p = .007), and gallbladder wall thickness >6.2 mm (p = .001) as independent risk factors for grade C in DLC. CONCLUSION: The difficulty score proposed in TG18 provides an objective framework for evaluating surgical difficulty, allowing for more accurate risk assessments and improved preoperative planning in DLC for AC.

Exogenous and endogenous factors affecting stock market transactions: A Hawkes process analysis of the Tokyo Stock Exchange during the COVID-19 pandemic.

Transactions in financial markets are not evenly spaced but can be concentrated within a short period of time. In this study, we investigated the factors that determine the transaction frequency in financial markets. Specifically, we employed the Hawkes process model to identify exogenous and endogenous forces governing transactions of individual stocks in the Tokyo Stock Exchange during the COVID-19 pandemic. To enhance the accuracy of our analysis, we introduced a novel EM algorithm for the estimation of exogenous and endogenous factors that specifically addresses the interdependence of the values of these factors over time. We detected a substantial change in the transaction frequency in response to policy change announcements. Moreover, there is significant heterogeneity in the transaction frequency among individual stocks. We also found a tendency where stocks with high market capitalization tend to significantly respond to external news, while their excitation relationship between transactions is weak. This suggests the capability of quantifying the market state from the viewpoint of the exogenous and endogenous factors generating transactions for various stocks.

Head impact differences in blind football between Rio 2016 and Tokyo 2020 Paralympic Games: video-based observational study.

OBJECTIVE: In Tokyo 2020 Paralympic Games, there were the rule and goal size changes at the blind football competition. This study aimed to compare the scoring and head impact characteristics during blind football competition between the Rio 2016 and Tokyo 2020 Paralympic Games using the official videos. DESIGN: Video-based observational study. PARTICIPANTS: In total, 36 blind football (men's football 5-a-side) game videos were obtained from the official International Paralympic Committee. PRIMARY AND SECONDARY OUTCOME MEASURES: Head impact was defined as the sudden contact of any object with the head. Videos were analysed to assess the number of scores and head impacts along with their corresponding details (ie, round, playing phase, scoring situation, impact situation, occurrence area, impact object, head impact site, fall and foul). RESULTS: The total number of goals scored at the Tokyo 2020 Paralympic Games was nearly double that at the Rio 2016 Paralympic Games. Regarding head impacts, a total of 2036 cases (Rio 2016, n=1105; Tokyo 2020, n=931) were evaluated. Significant differences were observed in head impact characteristics between the Rio 2016 and Tokyo 2020 Paralympic Games among seven outcomes (round, scoring situation, impact situation, occurrence area, impact object, site of head impact and fall). CONCLUSIONS: Compared with the Rio 2016 Paralympic Games, the Tokyo 2020 Paralympic Games showed an increase in the number of points scored and different head impact characteristics.

Meeting report: the 66th annual meeting of the Japanese Radiation Research Society in Tokyo, Japan, 6-8 November 2023.

The 66th Annual Meeting of the Japanese Radiation Research Society took place in Tokyo, Japan, from 6 to 8 November 2023. The meeting covered a wide range of radiation research topics, including basic mechanisms involved in radiation effects, translational research, and epidemiology. Some sessions were jointly organized with the International Commission on Radiological Protection (ICRP). Here, we report on some plenary and keynote talks presented at the meeting.

Analysis of Tokyo 2020 Olympic modern pentathlon equestrian jumping results.

Modern Pentathlon (MP) includes an equestrian Jumping discipline, with horses drawn blindly by unfamiliar riders. At the Tokyo 2020 Olympic Summer Games, concerns regarding inadequate horsemanship generated adverse publicity for MP. Conventional stadium Jumping in Tokyo provided an opportunity for comparison of the two closest Olympic equestrian Jumping disciplines. The objectives of this study were to complete an objective analysis of the Tokyo MP riding phases, and to test the hypothesis that MP riding faults in women's and men's Tokyo competitions combined were more frequent than in the Individual Jumping Qualifier (JQ). Types of faults for Tokyo MP (n = 71 riders) and JQ (n = 73 riders) were tabulated from published official results and detailed observation of online videos of each competition. Fault distributions were compared using Chi-square analysis (significance at P < .05). MP riders had more jumping faults (15.4 %) than JQ (7.8 %, P < .0001). Both MP and JQ riders had more faults at oxers (17.1 %, P < .0001 and 9.7 %, P = .0171, respectively) than verticals (14.5 % and 6.2 %). JQ (9.8 %, P = .0093) but not MP (15.7 %, p = .5166) riders had more faults in the second half of the course compared to the first half (5.7 % and 15.0 %, respectively). Double clear rounds (no jumping or time faults) were 4.9 times more likely in JQ (34.2 %) than in MP (6.9 %: P < .0001). Proposed solutions to decrease MP fault frequency include lower maximum fence heights, fewer jumping efforts, and a more liberal re-ride policy.

The Association between Menstrual Symptoms and Presenteeism: A Cross-Sectional Study for Women Working in Central Tokyo.

Menstrual symptoms lower women's work performance, but to what extent one's performance declines during the perimenstrual periods is unclear. This cross-sectional study evaluated relative presenteeism by the severity of menstrual symptoms in working women. Participants included women who joined a health promotion event in Tokyo. The severity of PMS and symptoms during menstruation were categorized based on their frequency, and the outcome variable was relative presenteeism as the ratio of work performance during the perimenstrual periods to that during the inter-menstrual period. An analysis of variance (ANOVA) was performed. Of the 312 participants, 238 were eligible, 50% of whom claimed severe symptoms in either PMS or during menstruation. Participants were divided into four groups (1) without severe menstrual symptoms, (2) severe PMS alone, (3) severe symptoms during menstruation alone, and (4) both severe PMS and symptoms during menstruation-and the mean relative presenteeism was 91% (standard deviation (SD) 23), 69% (SD 21), 76% (SD 16), and 69% (SD 27), respectively (p < 0.01). A between-group comparison revealed statistically significant differences in relative presenteeism, when group (1) served as the criterion for comparisons (p < 0.01). This study demonstrates that severe PMS alone, as well as both severe PMS and symptoms during menstruation, particularly decreased work performance.