Trends in Participation in Rubella Antibody Testing among Working-Aged Men during Annual Health Check-Ups from 2019 to 2022 in Japan.

In 2019, the Japanese government established a scheme for rubella antibody testing of men born between 1962 and 1978 during workplace health check-ups. However, the use of vouchers for rubella antibody testing was limited. Health check-up data analyses are needed to determine the reason why rubella antibody testing is not widely used. In this study, we aimed to describe changes in rubella antibody test-taking behavior during health check-ups during the first 3 years of the rubella catch-up campaign in Japan. In 2019, 2020, and 2021 (2020 in some areas) vouchers were sent to men born during the fiscal years 1972-1978, 1966-1971, and 1962-1965, respectively. We calculated the prevalence in men born between 1962 and 1978 who underwent rubella antibody testing during mandatory health check-ups under the Industrial Health and Safety Act. Rubella antibody testing uptake was relatively high (approximately 15%) in all three age groups soon after the distribution of the vouchers and then declined to below 2% during the second and third years. Further population-based approaches with continuous public engagement are required in workplaces to effectively promote and expand the rubella vaccination program in Japan.

Metabolic Syndrome and the Increased Risk of Medically Certified Long-term Sickness Absence: A Prospective Analysis Among Japanese Workers.

BACKGROUND: Metabolic syndrome (MetS) has been associated with various chronic diseases that may lead to long-term sickness absence (LTSA), but there is lacking information on the direct association between MetS and LTSA. The present study aimed to investigate the all-cause and cause-specific associations between MetS and the risk of medically certified LTSA among Japanese workers. METHODS: We recruited 67,403 workers (57,276 men and 10,127 women), aged 20-59 years from 13 companies in Japan during their health check-ups in 2011 (11 companies) and 2014 (2 companies), and we followed them for LTSA events (≥30 consecutive days) until March 31, 2020. MetS was defined according to the Joint Interim Statement. A Cox proportional hazards regression model was used to estimate hazard ratios (HRs) and its 95% confidence intervals (CIs) for LTSA associated with MetS and its components. RESULTS: During 408,324 person-years of follow-up, 2,915 workers experienced LTSA. The adjusted HR for all-cause LTSA was 1.54 (95% CI, 1.41-1.68) among those with MetS compared to those without MetS. In cause-specific analysis, HRs associated with MetS significantly increased for LTSA due to overall physical disorders (1.76); cardiovascular diseases (3.16); diseases of the musculoskeletal system and connective tissue (2.01); cancers (1.24); obesity-related cancers (1.35); mental, behavioral, and neurodevelopmental disorders (1.28); reaction to severe stress and adjustment disorders (1.46); and external causes (1.46). The number of MetS components were also significantly associated with increased LTSA risk. CONCLUSION: MetS was associated with an increase in the risk of LTSA due to various diseases among Japanese workers.

Estimated Glomerular Filtration Rate and Hearing Impairment in Japan: A Longitudinal Analysis Using Large-Scale Occupational Health Check-Up Data.

Several longitudinal studies have examined associations between renal dysfunction and hearing impairment. Here, we explored the longitudinal association between estimated glomerular filtration rate (eGFR) and hearing impairment among the working-age population in Japan. Participants were 88,425 males and 38,722 females aged 20-59 years, without hearing impairment at baseline (2013), who attended Japanese occupational annual health check-ups from 2013 to 2020 fiscal year. eGFR was categorized into four groups (eGFR upper half of ≥90, lower half of ≥90 (reference), 60-89, and <60 mL/min/1.73 m2). Low- and high-frequency hearing impairment were assessed using data from pure-tone audiometric testing. A Cox proportional hazards model was applied to estimate hazard ratio (HR) values for hearing impairment. Low eGFR did not increase the risk of low- or high-frequency hearing impairment. For males, multivariable-adjusted HR of high-frequency hearing impairment was 1.16 (95% confidence interval, 1.01-1.34) for the upper half of the ≥90 mL/min/1.73 m2; however, this positive association between high eGFR and high-frequency hearing impairment did not appear to be robust in a number of sensitivity analyses. We conclude that, among the Japanese working-age population, eGFR was not generally associated with hearing impairment in people of either sex.

Non-High-Density Lipoprotein Cholesterol and Risk of Cardiovascular Disease: The Japan Epidemiology Collaboration on Occupational Health Study.

AIMS: We aimed to investigate the association between non-high-density lipoprotein cholesterol (non-HDL-C) levels and the risk of cardiovascular disease (CVD) and its subtypes. METHODS: In this contemporary cohort study, we analyzed the data of 63,814 Japanese employees aged ≥ 30 years, without known CVD in 2012 and who were followed up for up to 8 years. The non-HDL-C level was divided into 5 groups: ＜110, 110-129, 130-149, 150-169, and ≥ 170 mg/dL. The Cox proportional hazards model was used to calculate the hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) for CVD and its subtypes associated with each non-HDL-C group, considering 130-149 mg/dL as the reference group. RESULTS: During the study period, 271 participants developed CVD, including 78 myocardial infarctions and 193 strokes (102 ischemic strokes, 89 hemorrhagic strokes, and 2 unknowns). A U-shaped association between non-HDL-C and stroke was observed. In the analysis of stroke subtypes, the multivariable-adjusted HR (95% CI) for hemorrhagic stroke was 2.61 (1.19-5.72), 2.02 (0.95-4.29), 2.10 (1.01-4.36), and 1.98 (0.96-4.08), while that for ischemic stroke was 1.54 (0.77-3.07), 0.91 (0.46-1.80), 0.73 (0.38-1.41), and 1.50 (0.87-2.56) in the ＜110, 110-129, 150-169, and ≥ 170 mg/dL groups, respectively. Individuals with elevated non-HDL-C levels had a higher risk of myocardial infarction. CONCLUSIONS: High non-HDL-C levels were associated with an increased risk of myocardial infarction. Moreover, high and low non-HDL-C levels were associated with a high risk of stroke and its subtypes among Japanese workers.

Hepatic Steatosis Index and Chronic Kidney Disease among Middle-Aged Individuals: A Large-Scale Study in Japan.

BACKGROUND: Though nonalcoholic fatty liver disease (NAFLD) is related to chronic kidney disease (CKD), it is unclear whether the hepatic steatosis index (HSI), a screening tool for NAFLD, is related to CKD. The present study investigated the relationship between HSI and CKD among middle-aged individuals in Japan. METHODS: Subjects were adults (aged 40-64 years) who received an annual health checkup in Japan between April 2013 and March 2014. Height and weight were measured, and venous blood samples were obtained to determine alanine aminotransferase (ALT), aspartate aminotransferase (AST), and creatinine levels. HSI was calculated by the following formula: HSI = 8 × ALT/AST ratio + body mass index (+2, if diabetes; +2, if female). CKD was defined as an estimated glomerular filtration rate < 60 mL/min/1.73 m2 and/or urinary protein of ≥ (+). Logistic regression analysis was performed to estimate the odds ratio (OR) and its 95% confidence interval (CI) for CKD. RESULTS: Data of 94,893 adults were analyzed. Compared with men with an HSI < 30, men with 30 ≤ HSI ≤ 36 (OR: 1.50, 95% CI: 1.40-1.61) and HSI > 36 (OR: 2.14, 95% CI: 1.99-2.31) had significantly higher ORs for CKD. Moreover, there was a significant dose-response relationship between HSI and CKD (P for trend < 0.001). Even after adjusting for confounders, the significant results persisted. These findings in men were similar to those in women. CONCLUSIONS: This study showed that the HSI was associated with CKD among middle-aged adults in Japan. Additionally, a dose-response relationship of HSI to CKD was observed. The present study suggested that it might be useful to monitor the HSI among middle-aged individuals to detect CKD at an early stage.

Visit-to-visit variability of blood pressure and cardiovascular events among the working-age population in Japan: findings from the Japan Epidemiology Collaboration on Occupational Health Study.

Increased visit-to-visit variability (VVV) of blood pressure, which is calculated based on several readings, has been suggested to be a significant predictor of cardiovascular events and mortality, independent of mean blood pressure. This study examined associations between the VVV of systolic blood pressure (SBP) measured annually and cardiovascular disease (CVD) events among 72,617 Japanese subjects. Data were obtained from the Japan Epidemiology Collaboration on Occupational Health Study, which is an ongoing epidemiological survey of workers in Japan. VVV was calculated as the coefficient of variation of SBP readings from 2008 to 2011; information on fatal and nonfatal CVD events was collected from registries of specific outcomes between April 2012 and March 2019. A Cox proportional hazards model was applied to investigate associations after adjusting for mean SBP between 2008 and 2011 and covariates. During the 7-year follow-up period, there were 63 CVD fatalities and 314 CVD events (combining fatal and nonfatal events). The results showed that a one-standard deviation increase in VVV was associated with a significant increase in the risk of CVD mortality (hazard ratio [HR] = 1.42; 95% confidence interval [CI] = 1.32-1.54); those in the highest tertile had a 3.20 times (95% CI = 1.26-8.17) higher risk of CVD mortality than those in the lowest tertile. We found less pronounced associations regarding CVD events (HR = 1.08, 95% CI = 1.02-1.15). In conclusion, VVV was significantly associated with CVD mortality in our Japanese working population.

Prediabetes, Diabetes, and the Risk of All-Cause and Cause-Specific Mortality in a Japanese Working Population: Japan Epidemiology Collaboration on Occupational Health Study.

OBJECTIVE: Prediabetes has been suggested to increase risk for death; however, the definitions of prediabetes that can predict death remain elusive. We prospectively investigated the association of multiple definitions of prediabetes with the risk of death from all causes, cardiovascular disease (CVD), and cancer in Japanese workers. RESEARCH DESIGN AND METHODS: The study included 62,785 workers who underwent a health checkup in 2010 or 2011 and were followed up for death from 2012 to March 2019. Prediabetes was defined according to fasting plasma glucose (FPG) or glycated hemoglobin (HbA1c) values or a combination of both using the American Diabetes Association (ADA) or World Health Organization (WHO)/International Expert Committee (IEC) criteria. The Cox proportional hazards regression model was used to investigate the associations. RESULTS: Over a 7-year follow-up, 229 deaths were documented. Compared with normoglycemia, prediabetes defined according to ADA criteria was associated with a higher risk of all-cause mortality (hazard ratio [HR] 1.53; 95% CI 1.12-2.09) and death due to cancer (HR 2.37; 95% CI 1.45-3.89) but not with death due to CVD. The results were materially unchanged when prediabetes was defined according to ADA FPG, ADA HbA1c, WHO FPG, or combined WHO/IEC criteria. Diabetes was associated with the risk of all-cause, CVD, and cancer deaths. CONCLUSIONS: In a cohort of Japanese workers, FPG- and HbA1c-defined prediabetes, according to ADA or WHO/IEC, were associated with a significantly increased risk of death from all causes and cancer but not CVD.

Smoking and Long-Term Sick Leave in a Japanese Working Population: Findings of the Japan Epidemiology Collaboration on Occupational Health Study.

BACKGROUND: Few studies have investigated the association between tobacco smoking and sick leave (SL) in Japan. METHODS: We followed 70 896 workers aged 20-59 years (60 133 males, 10 763 females) between April 2012 and March 2017. A Cox proportional hazards model was used to investigate the associations between smoking (smoking status and intensity) and long-term SL (ie, SL lasting ≥30 consecutive days). Cause-specific analyses were also conducted. RESULTS: A total of 1777 people took long-term SL during a follow-up of 307 749 person years. Compared with never-smokers, current smokers were at a higher risk of long-term SL (hazard ratio [HR] = 1.32; 95% confidence interval [CI] = 1.19 to 1.48). Cause-specific analyses revealed that current smoking was associated with a higher risk of SL due to all physical disorders (HR = 1.44, 95% CI = 1.22 to 1.69), cancer (HR = 1.49, 95% CI = 1.10 to 2.01), cardiovascular disease (CVD; HR = 2.16, 95% CI = 1.31 to 3.55), and injuries/external causes (HR = 1.83, 95% CI = 1.31 to 2.58). Former smokers were at a higher risk of SL due to cancer at a borderline significance level (HR = 1.38, 95% CI = 0.99 to 1.92). Low-intensity smoking (ie, 1-10 cigarettes smoked per day) was associated with all-cause SL, SL due to CVD, and SL due to injuries/external causes compared with never-smokers. CONCLUSION: In a large cohort of working-age Japanese, smoking was associated with a greater risk of long-term SL. Greater effort is needed to mitigate disease burden associated with smoking at workplace in Japan. IMPLICATIONS: Our study contributes to the literature on the association between smoking and SL in several ways. First, the study was conducted among a Japanese working population. While the association has been extensively studied in Western setting, few attempts have been made elsewhere. Second, cause-specific analyses were undertaken in our study. Third, we paid attention to the effect of low-intensity smoking on SL given that there is growing evidence of an elevated health risk associated with low-intensity smoking.

Elevated alanine aminotransferase and low aspartate aminotransferase/alanine aminotransferase ratio are associated with chronic kidney disease among middle-aged women: a cross-sectional study.

BACKGROUND: Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) to ALT ratio (AST/ALT ratio) have been shown to be related to non-alcoholic fatty liver disease or insulin resistance, which was associated with chronic kidney disease (CKD). However, it is unclear whether ALT and AST/ALT ratio are associated with CKD. In this study, we examined the relationship of ALT and AST/ALT ratio to CKD among middle-aged females in Japan. METHODS: The present study included 29,133 women aged 40 to 64 years who had an annual health checkup in Japan during April 2013 to March 2014. Venous blood samples were collected to measure ALT, AST, gamma-glutamyltransferase (GGT), and creatinine levels. In accordance with previous studies, ALT > 40 U/L and GGT > 50 U/L were determined as elevated, AST/ALT ratio < 1 was regarded as low, and CKD was defined as estimated glomerular filtration rate < 60 mL/min/1.73 m2 and/or proteinuria. Logistic regression model was used to calculate the odds ratio (OR) and 95% confidence interval (CI) for CKD. RESULTS: "Elevated ALT and elevated GGT" and "elevated ALT and non-elevated GGT" significantly increased the OR for CKD when compared with "non-elevated ALT and non-elevated GGT" (OR: 2.56, 95% CI: 2.10-3.12 and OR: 2.24, 95% CI: 1.81-2.77). Compared with "AST/ALT ratio ≥ 1 and non-elevated GGT", "AST/ALT ratio < 1 and elevated GGT" and "AST/ALT ratio < 1 and non-elevated GGT" significantly increased the OR for CKD (OR: 2.73, 95% CI: 2.36-3.15 and OR: 1.68, 95% CI: 1.52-1.87). These findings still remained after adjustment for confounders. CONCLUSIONS: Elevated ALT was associated with CKD regardless of GGT elevation. Moreover, low AST/ALT ratio was also associated with CKD independent of GGT elevation.

Eating quickly is associated with a low aspartate aminotransferase to alanine aminotransferase ratio in middle-aged adults: a large-scale cross-sectional survey in Japan.

BACKGROUND: An elevated alanine aminotransferase (ALT) and a low aspartate aminotransferase (AST) to ALT ratio (AST/ALT ratio) suggest nonalcoholic fatty liver disease and nonalcoholic steatohepatitis, increasing the risk of liver cirrhosis and hepatocellular carcinoma. In addition, eating quickly has been found to be associated with outcomes such as obesity. This study sought to investigate the relationship between eating quickly and an elevated ALT or a low AST/ALT ratio in Japanese middle-aged adults. METHODS: The present study included 283,073 adults aged 40-64 years who had annual health checkups in Japan from April 2013 to March 2014. The data of serum parameters and lifestyle factors, including eating speed, were analyzed. An elevated ALT was defined as > 40 U/L, and a low AST/ALT ratio was defined as < 1. Logistic regression analysis was performed to calculate the odds ratios (ORs) and the 95% confidence intervals (CIs) for an elevated ALT and a low AST/ALT ratio. RESULTS: Significantly increased ORs for an elevated ALT were observed in men (OR: 1.45, 95% CI: 1.41-1.49) and women (OR: 1.34, 95% CI: 1.25-1.43). Moreover, eating quickly significantly increased the ORs for a low AST/ALT ratio in men (OR: 1.53, 95% CI: 1.50-1.56) and women (OR: 1.36, 95% CI: 1.31-1.41). When the analysis was limited to those with ALT ≤40 U/L, eating quickly had significantly increased ORs for a low AST/ ALT ratio, regardless of sex. CONCLUSIONS: Eating quickly was significantly associated with an elevated ALT and a low AST/ALT ratio. In addition, eating quickly was significantly associated with a low AST/ALT ratio even for those without ALT elevation. This study suggested that modification of eating speed may contribute to reducing the risk for an elevated ALT and a low AST/ALT ratio.

Diabetes, prediabetes, and suicide deaths in a Japanese working population.

OBJECTIVE: To examine the association of diabetes and prediabetes with suicide deaths in a Japanese working population. METHODS: A nested case-control study was conducted using data from the Japan Epidemiology Collaboration on Occupational Health Study. During 8 years of follow-up, we identified 56 registered cases of suicide death that had information on fasting plasma glucose or glycated hemoglobin A1c at any health check-up during the past 3 years prior to suicide. For each case, we randomly selected five controls matched for age, sex, and worksite. We used the latest health check-up data for analysis. We defined diabetes status based on the American Diabetes Association criteria and used a conditional logistic regression model to investigate the association. RESULTS: Adjusted odds ratios and 95% confidence intervals for suicide death were 0.67 (0.32-1.41) and 3.53 (1.05-11.91) for prediabetes and diabetes, respectively, compared to normoglycemia. Similar results were obtained when diabetes status was exclusively defined by the fasting plasma glucose or glycated hemoglobin A1c level. CONCLUSION: Diabetes, but not prediabetes, was associated with a higher risk of suicide death, compared with normoglycemia, among a Japanese working population.

Clustering of Lifestyle Factors and Its Association with Low Back Pain: A Cross-Sectional Study of Over 400,000 Japanese Adults.

PURPOSE: Although many studies have indicated the association between low back pain (LBP) and lifestyle factors, the combined effect of lifestyle factors on LBP has not been adequately investigated. We aimed to investigate the association between a cluster of unhealthy lifestyle behaviors and LBP using a large cohort of Japanese adults. METHODS: We included 419,003 adults aged over 20 years who underwent an annual health checkup between April 2013 and March 2014 in Japan. Information on the following lifestyle factors was collected using the standardized questionnaire: smoking, alcohol intake, exercise, physical activity, walking speed, weight control, eating habits, and sleep. Each factor was evaluated as a dichotomous variable (1: health risk, 0: no health risk). A lifestyle risk score was calculated by summing the score of each lifestyle factor (range: 0-12) and was categorized into three groups (low, moderate, high). LBP was defined as self-reported LBP under treatment. Logistic regression analysis was conducted to calculate the odds ratio (OR) and 95% confidence interval (CI) for LBP. RESULTS: In multivariable logistic regression analysis, the OR for LBP was significantly higher in the moderate-risk score group (adjusted OR: 1.33 [95% CI: 1.23-1.44] in men; 1.40 [95% CI: 1.27-1.54] in women) and the high-risk score group (adjusted OR: 1.54 [95% CI: 1.43-1.67] in men; 1.83 [95% CI: 1.64-2.03] in women) than in the low-risk score group. A trend of higher risk of LBP associated with higher lifestyle risk score was observed in both sexes (p for trend < 0.001). These results were similar even in subgroup analysis by age and body mass index (BMI). CONCLUSION: Clustering of unhealthy lifestyles was associated with increased risk of LBP regardless of age and BMI. These results may provide implications for better prevention and management of LBP, considering modifiable lifestyle factors.

A nationwide cross-sectional survey on hepatitis B and C screening among workers in Japan.

In Japan, there is no publicly funded screening for hepatitis B virus (HBV) and hepatitis C virus (HCV) infections (using HBs antigen and HCV antibody, respectively) among workers, and workplace health programmes play a crucial role in reducing viral hepatitis-related deaths. The national number of hepatitis screening tests conducted in the workplace is unknown. To provide baseline data for policy formulation, we conducted a nationwide survey to estimate these parameters using data from approximately 10.5 million workers (6.8 million men and 3.8 million women) who underwent mandatory health examinations in their workplaces between April 2016 and March 2017. Among these workers, 494,303 (5.23%, 95% confidence interval [CI] 5.22%-5.24%) and 313, 193 (3.82%, 95% CI 3.81%-3.84%) were screened for HBV and HCV, respectively. Among those who were screened, 0.28% (95% CI 0.27-0.30%) and 0.35% (95% CI 0.33-0.37%) tested positive for HBs antigen and HCV antibody, respectively. According to the age-specific prevalence from the survey an estimated 0.30 and 0.14 million workers in Japan require treatment for HBV and HCV, respectively. To reduce viral hepatitis-related deaths by efficiently identifying workers who need treatment and promoting access to treatment, one-time hepatitis screening of all workers should be considered.

Correction to: Cross-sectional study of associations between normal body weight with central obesity and hyperuricemia in Japan.

After publication of this article [1], it was brought to our attention that there is an error in the Table 5, which "Cases" should be revised to "HU" in Table 5. The original publication has been corrected.

Trajectories of body mass index and waist circumference before the onset of diabetes among people with prediabetes.

BACKGROUND & AIMS: To investigate trajectories of body mass index (BMI) and waist circumference (WC) among prediabetic people who progressed to diabetes, people who remained with prediabetes, and those who returned to normoglycemia. METHODS: We used data from 22,945 prediabetic people who received an annual health checkup for up to eight years. The development of diabetes was defined using the American Diabetes Association criteria. People who did not progress to diabetes during the observation period were classified as 'remained with prediabetes' or 'returned to normoglycemia', based on their last health checkup data. Trajectories of BMI and WC were evaluated using linear mixed models for repeated measures, with adjustment for a wide range of covariates. RESULTS: During the study period, 2972 people progressed to diabetes, 4706 returned to normoglycemia, and 15,267 remained with prediabetes. People who progressed to diabetes had a larger increase in mean BMI from 7 years to 1 year prior to diagnosis, which was about three times that of people who remained with prediabetes (annual change rate, 0.20 [95% confidence interval; 0.15 to 0.24] vs 0.06 [0.04 to 0.08] kg/m2 per year, P < 0.001), regardless of their BMI levels at the initial health checkup. Among people who returned to normoglycemia, mean BMI remained almost the same over time (-0.04 [-0.09 to 0.002] kg/m2 per year), except for those with obesity (-0.16 [-0.28 to -0.05] kg/m2 per year). As for WC, the annual change rate among people who developed diabetes was about 7 times that of people who remained with prediabetes (0.38 [0.32 to 0.45] vs 0.05 [0.03 to 0.08] cm per year, P < 0.001). We also observed a constant mean WC over time among people who had no central obesity and later returned to normoglycemia (-0.02 [-0.06 to 0.03] cm per year), and an annual decrease in mean WC among those who had central obesity and later returned to normoglycemia (-0.40 [-0.47 to -0.32] cm per year). CONCLUSIONS: Our study provides strong evidence that avoiding weight gain could help prediabetic people minimize the risk of developing diabetes, regardless of whether they are obese. Losing weight could help obese people restore normoglycemia from a prediabetic state, whereas maintaining current weight may help nonobese people return to normoglycemia.

Cross-sectional study of associations between normal body weight with central obesity and hyperuricemia in Japan.

BACKGROUND: Several studies have shown that normal weight with central obesity (NWCO) is associated with cardiovascular disease risk factors such as hypertension, dyslipidemia and diabetes. However, the relationship between NWCO and hyperuricemia has not been studied in detail. METHODS: We investigated the association between NWCO and hyperuricemia among Japanese adults aged 40-64 years who had undergone periodic health examinations between April 2013 and March 2014. Obesity was defined as a body mass index (BMI) ≥25 kg/m2 and central obesity was determined as a waist-to-height ratio (WHtR) ≥0.5. We classified the participants into the following groups based according to having obesity and central obesity: normal weight (BMI 18.5-24.9 kg/m2) without (NW; WHtR < 0.5) and with (NWCO) central obesity, and obesity without (OB) and with (OBCO) central obesity. Hyperuricemia was defined as serum uric acid > 7.0 and ≥ 6.0 mg/dL in men and women, respectively, or under medical treatment for hyperuricemia. Alcohol intake was classified as yes (daily and occasional consumption) and none (no alcohol consumption). Odds ratios (OR) and 95% confidence intervals (CI) for hyperuricemia were calculated using a logistic regression model. RESULTS: We analyzed data derived from 96,863 participants (69,241 men and 27,622 women). The prevalences of hyperuricemia in men and women were respectively, 21.4 and 11.0%, and of participants with NWCO respectively 15.6 and 30.0%. The adjusted OR for hyperuricemia was significantly increased in OBCO compared with NW, regardless of sex (men: OR, 2.12; 95%CI; 2.03-2.21; women: OR, 3.54; 95%CI, 3.21-3.90) and were statistically significant in NWCO compared with NW (men: OR, 1.44; 95%CI, 1.36-1.52; women: OR, 1.41; 95%CI, 1.27-1.57). The results were similar regardless of alcohol consumption. CONCLUSIONS: We found that NWCO and OBCO were associated with hyperuricemia in middle-aged Japanese men and women. Middle-aged Japanese adults with normal weight but having central obesity should be screened using a combination of BMI and WHtR and educated about how to prevent hyperuricemia.

BMI and Medically Certified Long-Term Sickness Absence Among Japanese Employees.

OBJECTIVE: In contrast to the association between excess weight and sickness absence (SA), the association in relation to underweight has been under-researched. This study aimed to examine the effects of BMI at both extremes of its distribution on SA. METHODS: Data came from the Japan Epidemiology Collaboration on Occupational Health study of 77,760 workers aged 20 to 59 years (66,166 males, 11,594 females). Information was collected on medically certified long-term SA (LTSA) (i.e., SA lasting ≥ 30 consecutive days) from April 2012 to March 2017. A sex-specific Cox proportional hazards model was used to investigate the associations. RESULTS: Among males, both obesity (hazard ratio [HR] = 1.81, 95% CI: 1.50-2.17) and underweight (HR = 1.56, 95% CI: 1.23-1.96) were significantly associated with LTSA compared with normal weight. This U-shaped association between BMI categories and LTSA was observed both for mental and physical disorders. Among females, an elevated risk was observed among those with overweight (HR = 1.54, 95% CI: 1.16-2.05). CONCLUSIONS: In a cohort of the Japanese working-age population, both obesity and underweight were associated with a greater risk of LTSA in males. Future research should not overlook the excess risk of LTSA associated with underweight.

Smoking cessation after long-term sick leave due to cancer in comparison with cardiovascular disease: Japan Epidemiology Collaboration on Occupational Health Study.

In occupational settings, smokers may take quitting smoking seriously if they experienced long-term sick leave due to cancer or cardiovascular disease (CVD). However, no study has elucidated the smoking cessation rate after long-term sick leave. We examined the smoking cessation rate after long-term sick leave due to cancer and CVD in Japan. We followed 23 survivors who experienced long-term sick leave due to cancer and 39 survivors who experienced long-term sick leave due to CVD who reported smoking at the last health exam before the leave. Their smoking habits before and after the leave were self-reported. Logistic regression was used to calculate adjusted smoking cessation rates. Smoking cessation rate after long-term sick leave due to cancer was approximately 70% and that due to CVD exceeded 80%. The adjusted smoking cessation rate was 67.6% (95% confidence interval [CI]: 47.0, 88.2) for cancer and 80.7% (95% CI: 67.7, 93.8) for CVD. Smoking cessation rate after a longer duration of sick leave (≥60 d) tended to increase for both CVD and cancer. Although any definite conclusion cannot be drawn, the data suggest that smoking cessation rate after long-term sick leave due to CVD is slightly higher than that for cancer.

Five-year cumulative incidence of overweight and obesity, and longitudinal change in body mass index in Japanese workers: The Japan Epidemiology Collaboration on Occupational Health Study.

OBJECTIVE: The present study aimed to estimate cumulative incidence of overweight and obesity and describe 5-year longitudinal changes in body mass index (BMI) in a large occupational cohort in Japan. METHODS: Participants were 55 229 Japanese employees, who were aged 20-59 years and attended at all subsequent annual health check-ups between 2009 and 2014. Mixed model analysis was performed to examine the effects of age and cohort by gender on BMI change, with age as a random variable. Cumulative incidence of overweight (23.0≤ BMI <27.5 kg/m2 ) and obesity (BMI ≥27.5 kg/m2 ) was calculated. Logistic regression analysis was used to estimate odds ratios for the incidence of overweight and obesity according to age group. RESULTS: The incidence of overweight and obesity was approximately double in men (28.3% and 6.7%, respectively) compared to women (14.3% and 3.9%, respectively).The incidence of obesity decreased with age in men, but did not differ according to age in women (P for trend: .02 and .89, respectively). Among overweight participants, the incidence of obesity was higher in women (18.9%) than men (14.5%) and decreased with advancing age (P for trend: <.001 in men and .003 in women). Mean BMI was higher in men than women in all age groups throughout the period. Younger cohorts tended to have a higher BMI change compared with older cohorts. CONCLUSIONS: In this Japanese occupational cohort, transition from overweight to obesity is higher in women than men, and the more recent cohorts had a higher change in mean BMI than the older cohorts.

Association between anthropometric indices of obesity and risk of cardiovascular disease in Japanese men.

OBJECTIVES: We aimed to compare the association of body mass index (BMI), waist circumference (WC), and waist-to-height ratio (WHtR) with risk of cardiovascular disease (CVD) among middle-aged working Japanese men. METHODS: A nested case-control study was performed among middle-aged male employees who underwent periodic health checkup. A total of 241 CVD cases were identified and matched individually on age, gender, and worksite with 1205 controls. Data on BMI, WC, WHtR, smoking, hypertension, diabetes, and dyslipidemia collected at 4 years before the event/index date were retrieved. Associations between BMI, WC, WHtR, and CVD risk were assessed by using conditional logistic regression models. RESULTS: The strength of the association of BMI, WC, and WHtR with CVD risk was similar. The smoking-adjusted odds ratio (95% confidence interval) for CVD was 1.60 (1.38-1.85), 1.53 (1.33-1.78), and 1.56 (1.35-1.81) for a 1 SD unit increase in BMI, WC, and WHtR respectively. After further adjustment for hypertension, diabetes, and dyslipidemia, these associations were attenuated but remained statistically significant. CONCLUSIONS: Measures of general (BMI) and abdominal (WC and WHtR) obesity were similarly associated with CVD in middle-aged Japanese men.