[Work environment that support workers with diseases to maintain a work-treatment balance in Ishikawa prefecture: relationship with company scale and type of industry].

OBJECTIVES: We investigated the support environments in companies in Ishikawa prefecture that aim to maintain a balance between work and treatment of their employees' diseases. The relationships between these strategies, company size, and type of industry were examined. METHODS: In 2016, as a part of a survey, questionnaires were sent to 1,491 companies with ≥ 50 employees. Of the 688 companies who responded (response rate, 46.1%), 624 companies who provided complete main survey data were included in the final analysis. The questionnaire acquired responses on systems for arranging working hours and sick leave, the role of occupational health physicians, and the outcomes of support that was offered over the last 3 years. The targeted diseases were mental health problems, such as depression, and physical diseases. Responses were compared according to the size of the company and type of industry. RESULTS: A total of 409 companies (65.5%) reported their experiences of helping employees maintain a balance between treatment and work over the last 3 years. Employees with depression received the most support. In 36.7% of the companies, some employees had retired due to their disease over the last 3 years, with the highest proportion in medical care and welfare businesses. Further, 66% of the companies had a support system to help employees with diseases, and the proportion of companies with flexible working hours and sick leave increased with the number of employees. The proportion of companies with shorter working hours and hourly paid leave was lower in the manufacturing industry and transportation/traffic business. The proportion of companies in which an occupational health physician interviewed employees who took sick leave and returned to work was 22%. CONCLUSIONS: Almost 70% of the companies reported supporting workers during their disease treatment. There were some differences in arranging these support systems between companies of varying sizes and type of industry. The enablement of companies to support workers with diseases so that they keep working and receive treatment requires consideration of company characteristics.

Health status of workers approximately 60 years of age and the risk of early death after compulsory retirement: A cohort study.

OBJECTIVES: The increasing number of working elderly people has enhanced the importance of workplace health promotion activities. We investigated the association between the health status of workers approximately 60 years of age and the risk of all-cause mortality after compulsory retirement in Japan. METHODS: The 2026 participants (1299 males and 727 females) had retired from a metal-products factory at ≥60 years of age. Baseline health examinations were conducted at 60 years of age and included questions about medical history and lifestyle factors; the participants also underwent a physical examination. The participants were followed up annually by mail for an average of 7.4 years. The association between health status at age 60 years and the risk of all-cause mortality was assessed by Cox proportional hazards regression analysis. RESULTS: During the study, 71 deaths were reported. The age- and sex-adjusted hazard ratio (HR [95% confidence interval]) for all-cause mortality was higher for males (HR, 3.41 [1.73-6.69]) compared with females, participants with a low body mass index (<18.5 kg/m2 ; HR 3.84 [1.91-7.73]) compared with normal body weight, smokers (HR, 2.63 [1.51-4.58]) compared with nonsmokers, and those with three or more of four metabolic abnormalities (obesity, high blood pressure, dyslipidemia, and glucose intolerance) (HR 2.29 [1.04-5.02]) compared with no metabolic abnormalities. The associations were unaffected by adjustment for these factors. CONCLUSION: Maintenance of an appropriate body weight, smoking cessation, and elimination of metabolic syndrome are required for older workers to prevent early death after retirement.

Serum Ferritin, Insulin Resistance, and ß-cell Dysfunction: A Prospective Study in Normoglycemic Japanese Men.

Objectives: The present cohort study investigated the relationship between serum ferritin levels and indices of insulin resistance and ß-cell dysfunction in a normoglycemic population without iron overload disorders. Methods: The study participants included 575 normoglycemic Japanese men aged 35-57 years with serum ferritin levels of 400 µg/L or less. Insulin resistance and ß-cell dysfunction were estimated at baseline and after 3 years by the homeostasis model assessments of insulin resistance and ß-cell function (HOMA-IR and HOMA-ß, respectively). To compare the subsequent changes in HOMA-IR and HOMA-ß over a 3-year follow-up period among 3 groups based on tertiles of baseline serum ferritin levels (4.9-87.1, 87.2-140.5, and 140.6-396.8 µg/L), the geometric mean HOMA-IR and HOMA-ß values at year 3 were calculated for each group using analysis of covariance, incorporating the respective log-transformed parameters at baseline in addition to age, body mass index and major confounding factors. Results: The multivariate-adjusted geometric mean HOMA-IR at year 3 was significantly higher in those in the highest and middle serum ferritin tertiles (1.24 and 1.22, respectively), compared with the lowest tertile (1.07) (p=0.009). When the total study participants were stratified by median body mass index (22.72 kg/m2), similar positive relationships were observed between serum ferritin levels and HOMA-IR for both obese and non-obese participants. However, the adjusted geometric mean HOMA-ß at year 3 was similar among the 3 serum ferritin groups. Conclusions: Elevated serum ferritin levels predicted a subsequent increase in HOMA-IR in normoglycemic Japanese men without iron overload disorders.

Dietary carbohydrate intake, presence of obesity and the incident risk of type 2 diabetes in Japanese men.

AIMS/INTRODUCTION: The present cohort study assessed the risk among Japanese men for developing type 2 diabetes, based on the percentage of energy intake from carbohydrates and degree of obesity. PARTICIPANTS AND METHODS: The participants were 2,006 male factory employees, and the macronutrient intake of each patient was measured using a self-administered diet history questionnaire. The incidence of diabetes was determined in annual blood examinations over a 10-year period. RESULTS: During the study, 232 participants developed diabetes. The crude incidence rates (/1,000 person-years) for different levels of carbohydrate intake as a percentage of calories consumed (<50.0, 50.0-57.4, 57.5-65.0, >65.0% of energy intake) were 16.5, 14.4, 12.7 and 17.6. Overall, carbohydrate intake was not associated with the risk of diabetes. However, there was significant interaction between carbohydrate intake and degree of obesity on the incidence of diabetes (P for interaction = 0.024). Higher carbohydrate intake was associated with elevated risk for diabetes among participants with a body mass index ≥25.0 kg/m(2) (P for trend = 0.034). For obese participants, the multivariate-adjusted hazard ratio for those with carbohydrate intakes >65% energy was 2.01 (95% confidence interval 1.08-3.71), which was significantly higher than that of participants with carbohydrate intakes 50.0-57.4% energy. CONCLUSIONS: Higher carbohydrate intake was associated with higher risk of diabetes in obese participants, but not in non-obese participants. Obese participants with carbohydrate intakes >65% energy should reduce their intakes to levels within the desirable carbohydrate energy proportion for Japanese (50-65% energy) to prevent development of type 2 diabetes.

HOMA-IR and the risk of hyperuricemia: a prospective study in non-diabetic Japanese men.

AIMS: To examine the relation of insulin resistant status determined by homeostasis model assessment of insulin resistance (HOMA-IR) with the risk of incident hyperuricemia. METHODS: The study participants included 2071 Japanese men without hyperuricemia and diabetes, aged 35-54 years. The participants had undergone annual heath examinations for 6 years to compare incident hyperuricemia (serum uric acid >416.4µmol/L (7.0mg/dL) and/or taking medication for hyperuricemia) in four groups based on quartiles of baseline HOMA-IR. RESULTS: During follow-up there were 331 incident cases of hyperuricemia. The hazard ratios for hyperuricemia, compared with HOMA-IR ≤0.66, were 1.42 (95% confidence interval 1.02-1.98) for HOMA-IR 0.67-0.98, 1.20 (0.86-1.68) for HOMA-IR 0.99-1.49 and 1.44 (1.04-1.98) for HOMA-IR ≥1.50 after adjustment for baseline serum uric acid, creatinine, hypercholesterolemia and hypertension status, age, alcohol intake, and smoking and exercise habits. The hazard ratio associated with an increase of one standard deviation in lnHOMA-IR (1.85 as one geometric standard deviation of HOMA-IR) was 1.14 (1.03-1.28) (p for trend=0.02). CONCLUSIONS: Increased HOMA-IR independently predicted the subsequent development of hyperuricemia. Insulin resistance itself or compensatory hyperinsulinemia may contribute to the development of hyperuricemia.

Overall sleep status and high sensitivity C-reactive protein: a prospective study in Japanese factory workers.

We investigated the relation between overall sleep status based on the modified Pittsburgh Sleep Quality Index (PSQI) global score and subsequent changes in serum high-sensitivity C-reactive protein (hsCRP) in a population of Japanese factory workers, who were predominantly female. A total of 991 Japanese with inflammation classified as low cardiovascular risk (baseline hsCRP < 1.0 mg L(-1) ) were grouped according to the presence or absence of unfavourable sleep, defined as a modified PSQI global score > 5.5 points. The subsequent changes in hsCRP after 3 years were then compared in the two groups. Analysis of covariance incorporating log-transformed baseline hsCRP, age, sex, lifestyle and physical and biochemical profiles was used to compare the geometric means of hsCRP at year 3 in each sleep status group. A logistic regression model incorporating the same variables was used to calculate the odds ratios for development of inflammation with a medium-to-high cardiovascular risk (hsCRP at year 3 ≥ 1.0 mg L(-1) ) comparing the presence or absence of unfavourable sleep habits. The multivariate-adjusted geometric mean of hsCRP at year 3 was significantly higher in subjects with unfavourable sleep habits compared with those with a normal pattern (0.275 versus 0.242 mg L(-1) ). The multivariate-adjusted odds ratio for developing increased and potentially pathogenic levels of inflammation due to unfavourable sleep was 2.08 (95% confidence interval = 1.29-3.35). There was a significant linear trend for the development of increased inflammation across the modified PSQI global scores (P = 0.04). Unfavourable sleep is associated with activation of low-grade systemic inflammation.

Associations between rice, noodle, and bread intake and sleep quality in Japanese men and women.

BACKGROUND: Previous studies have shown that a diet with a high-glycemic index is associated with good sleep quality. Therefore, we investigated the association of sleep quality with the intake of 3 common starchy foods with different glycemic indexes-rice, bread, and noodles-as well as the dietary glycemic index in a Japanese population. METHODS: The participants were 1,848 men and women between 20 and 60 years of age. Rice, bread, and noodle consumption was evaluated using a self-administered diet history questionnaire. Sleep quality was evaluated by using the Japanese version of the Pittsburgh Sleep Quality Index, and a global score >5.5 was considered to indicate poor sleep. RESULTS: Multivariate-adjusted odds ratios (95% confidence intervals) for poor sleep across the quintiles of rice consumption were 1.00 (reference), 0.68 (0.49-0.93), 0.61 (0.43-0.85), 0.59 (0.42-0.85), and 0.54 (0.37-0.81) (p for trend = 0.015); those for the quintiles of noodle consumption were 1.00 (reference), 1.25 (0.90-1.74), 1.05 (0.75-1.47), 1.31 (0.94-1.82), and 1.82 (1.31-2.51) (p for trend = 0.002). Bread intake was not associated with sleep quality. A higher dietary glycemic index was significantly associated with a lower risk of poor sleep (p for trend = 0.020). CONCLUSION: A high dietary glycemic index and high rice consumption are significantly associated with good sleep in Japanese men and women, whereas bread intake is not associated with sleep quality and noodle consumption is associated with poor sleep. The different associations of these starchy foods with sleep quality might be attributable to the different glycemic index of each food.

Association between a serum thyroid-stimulating hormone concentration within the normal range and indices of obesity in Japanese men and women.

OBJECTIVE: This cross-sectional study investigated the associations between the serum thyroid-stimulating hormone (TSH) concentration and indices of obesity in middle-aged Japanese men and women. METHODS: The participants were 2,037 employees (1,044 men and 993 women; age, 36-55 yr) of a metal products factory in Japan. Clinical examinations were conducted in 2009. We obtained a medical history and anthropometric measurements (body weight, body mass index [BMI] and waist circumference) and measured the serum TSH concentrations. The anthropometric indices were compared across serum TSH quartiles. The associations were evaluated separately according to the smoking status in men. RESULTS: The mean body weight (kg), BMI (kg/m(2)) and waist circumference (cm) were 69.2, 23.7 and 83.2 in men and 55.3, 22.3 and 74.3 in women, respectively. Men with a higher TSH concentration had higher body weight and BMI values (p for trend=0.016 and 0.019, respectively), and these significant associations were observed even after adjusting for age, smoking status and other potential confounders. The TSH level was not associated with waist circumference. We found a significant interaction between the TSH level and the smoking status on body weight (p for interaction=0.013) and a significant association between the TSH level and body weight in nonsmokers, but not in current smokers. No significant associations were observed between the TSH level and the anthropometric indices in women. CONCLUSION: Significant positive associations between the serum TSH concentration, body weight and BMI were detected in men only, and an interaction with the smoking status was observed for this association.

Mortality and causes of deaths of inhabitants with renal dysfunction induced by cadmium exposure of the polluted Jinzu River basin, Toyama, Japan; a 26-year follow-up.

BACKGROUND: We aimed to investigate the mortality and causes of deaths of inhabitants with renal dysfunction induced by cadmium (Cd) exposure caused by heavy environmental contamination. METHODS: We conducted a 26-year follow-up survey targeting 7529 inhabitants of the Cd-polluted Jinzu River basin and 2149 controls from non-polluted areas who participated in urinary examinations for proteinuria and glucosuria conducted in 1979 to 1984. When the residents were divided into 4 groups, no finding group, glucosuria group, proteinuria group, glucoproteinuria group, mortality risk ratios for all and specific causes of these groups in the polluted area were compared with that of controls without glucosuria and/or proteinuria after adjustments for age at baseline, smoking status, and history of hypertension using Cox's proportional hazard model. RESULTS: The mortality risk ratios for all causes of proteinuria and glucoproteinuria in men and glucosuria, proteinuria, and glucoproteinuria in women of the polluted areas significantly increased compared with those of the controls with no urinary findings. Respiratory, renal, and cardiovascular diseases and diabetes in men, and all diseases except cerebrovascular diseases in women contributed toward an increased mortality of exposed glucoproteinuria groups, which involved chronic Cd toxicosis with renal tubular dysfunction. In women, the mortality risks for cancer of the colon and rectum, uterus and kidney and urinary tract were significantly higher in the exposed proteinuria and glucoproteinuria groups, suggesting associations between renal damage and cancer risk. In exposed women, the no finding group and glucoproteinuria group also showed increased mortality from ischemic heart diseases, indicating that all exposed women may be at risk for ischemic heart diseases. Although the control glucosuria and/or proteinuria group also showed high mortality for diabetes and renal diseases, the increased risk ratio for renal disease mortality was much higher in exposed subjects with urinary findings, particularly in women. CONCLUSIONS: These findings indicate that inhabitants with renal effects caused by Cd exposure had a poor life prognosis over long-term observation in both genders. Particularly in women, renal tubular dysfunction indicated by glucoproteinuria may increase mortality from cancer, ischemic heart diseases, and renal diseases.

The effect of age on the relationships between work-related factors and heavy drinking.

AIMS: The aim of this study was to investigate age-related differences in the relationship between work-related factors and heavy drinking. METHODS: This study in 3,398 male workers at a factory in Japan examined data on heavy drinking, defined as an alcohol consumption >40 g/day, and work-related factors including occupation, shift work, and job stress evaluated using the Japanese version of the Karasek's Job Content Questionnaire (JCQ). In the present cross-sectional study, alcohol consumption was assessed using a self-administered diet history questionnaire (DHQ). RESULTS: The prevalence of heavy drinkers in the study population was 15.5% and rose with increasing age. An increase in the odds ratio (OR) for heavy drinking was observed consistently in blue-collar workers compared with white-collar workers in all age groups. In subjects aged 20-29 years, shift work had also increased the OR for heavy drinking. In subjects aged 40-49 years, the two groups with a lower decision latitude had an increased OR compared with the highest group. In subjects aged 20-29 years, the age adjusted OR for individuals who received the lowest level of social support in the workplace was increased significantly compared with the highest group (4.22 [95%CI, 1.07-16.62] ). On the other hand, social support showed a positive association with heavy drinking in subjects aged 40-49 and 50-59 years. Job demand was not related to heavy drinking in any of the age groups. CONCLUSIONS: Our findings suggest that occupation and work schedule are related to alcohol use more apparently in a younger age group and that psychosocial factors are related to enhancement or prevention of alcohol use.

Association between long working hours and sleep problems in white-collar workers.

The purpose of this study is to examine the association between long work hours and sleep disturbance among white-collar workers. We evaluated 1510 male white-collar full-time employees, between the ages of 18 and 59 years, using a comprehensive sleep quality questionnaire, the Pittsburgh Sleep Quality Index (PSQI). All subjects worked in a light metal products factory in Japan. The mean number of monthly overtime work hours was determined using data from the previous 6 months from timecard records. Subjects were divided into five groups based on quintiles of the mean number of monthly overtime work hours: <26 h month(-1); ≥26 but <40; ≥40 but <50; ≥50 but <63; and >63. Leisure time physical activity, drinking habits just before sleep, presence of family/partner and health status were used as confounding factors in the multiple regression model. The prevalence of short sleep hours, impairment of sleep efficiency and daytime dysfunction among seven components of PSQI increased, in a dose-response relationship, with overtime work hours. The prevalence of high global score (>5.5 points) was highest in workers with overtime hours ≥50 h week(-1). The odds ratios after adjustment for confounding factors for high global score using less than 26 h as a reference group were 1.67 for workers with ≥50 h and <63 h, and 1.87 for workers with 63 h and more. To conclude, the present results suggest that long work hours correlate with reduced sleep quality in a dose-response manner.

Dietary glycemic index, glycemic load and blood lipid levels in middle-aged Japanese men and women.

AIMS: This study investigated the association between dietary glycemic index (GI)/glycemic load (GL) and serum lipids in middle-aged Japanese men and women. METHODS: The study participants were employees of a metal products factory in Japan: 2,257 men and 1,598 women aged 35 years or older. Dietary GI and GL were assessed using a self-administered diet history questionnaire. Serum lipid levels, adjusted for age, body mass index, alcohol consumption, smoking, physical activity, menopause status, and dietary intake of total energy, saturated fatty acids, monounsaturated fatty acids, polyunsaturated fatty acids, cholesterol and fiber, were compared among GI/GL quintiles for each gender. RESULTS: No significant associations were observed between GI and adjusted serum lipids in men or women. In contrast, GL was inversely associated with HDL-cholesterol in men and women (p for trend=0.001 for men and < 0.001 for women), and positively associated with non-HDL-cholesterol (p for trend=0.010), LDL-cholesterol (p for trend=0.035) and triglycerides (p for trend=0.011) in women; however, alcohol drinking affected these associations; there was no association between GL and serum lipids in male nondrinkers and between GL and LDL-cholesterol in female nondrinkers. CONCLUSION: GL was inversely associated with HDL-cholesterol and positively associated with non-HDL-cholesterol in Japanese women. These associations in men were not observed in nondrinkers. A high-GL diet for women may have an atherogenic effect through these serum lipid abnormalities.

[Effect of smoke-free medical school on smoking behavior of medical students].

PURPOSE: The purpose of this study was to investigate the effect of designating a medical school environment as smoke-free on the smoking behavior of medical students. METHODS: The total environment of a medical school in Japan was designated as smoke-free in 2004. Smoking behavior was surveyed among approximately 640 students in each year during the period 2001-2007 (response rate 91.2%). Smoking rates were also monitored among each year's freshmen during their time at the school, before and after 2004. Attitudes to smoking among both current smokers and those who had quit smoking were also investigated. RESULTED: Smoking rates among all students declined after the medical school was declared smoke-free in 2004; the rates were highest in 2002 (41.2%) and lowest in 2007 (22.1%) among men. Smoking rates among each year's freshmen tended to increase as the school year progressed before 2004, but they tended to decrease after 2004. Comparison of smoking rates among identical students showed a decline from 36.0% in 2003 to 25.6% in 2004 (P < 0.05). The rate of smokers wishing to quit smoking increased significantly from 39.1% in 2003 to 60.2% in 2004 (P < 0.01). 20.8% of students who had quit smoking and 50.0% of students who had continued to smoke felt that they would not be confident about educating their patients in smoking cessation (P < 0.01). CONCLUSIONS: Making a medical school environment smoke-free could be very effective means to motivating medical students to change their attitudes to smoking and to quit.

[Effectiveness of lifestyle modification programs for control of blood pressure: a non-randomized controlled trial in Komatsu, Japan].

PURPOSE: A non-randomized controlled trial was conducted to evaluate the effectiveness of three lifestyle modification programs to reduce blood pressure: individual counseling only; counseling using group dynamics; and individual support using mail. METHODS: We enrolled men and women ages 20-69 with a systolic blood pressure (SBP) of 130-159 mmHg and/or a diastolic blood pressure of 85-99 mmHg (high-normal or mild hypertension). Participants were assigned to one of 4 groups: individual counseling (n = 134); group counseling (n = 79); mailing support (n = 127); and controls (with usual care) (n = 178). The three intervention programs included behavioral support for each person's lifestyle problems once a month for 6 months. Sex and age adjusted net blood pressure change (and 95% confidence intervals [CIs]) compared with the control group was calculated for each of the intervention groups. RESULTS: Net SBP change was the largest for the group counseling group: sex and age adjusted net SBP change was -6.5 mmHg (95% CI: -10.0, -3.0). Net SBP change for the mailing support group was also significant (-4.3 mmHg [95% CI: -7.3, -1.3]). Net SBP change for the individual counseling group was -2.5 mmHg (95% CI: -5.5, 0.5). Looking at the results separately by sex, net SBP reduction was also largest in women of the group counseling group, whereas improvement in men was similar among 3 groups (approximately 4 mmHg). Body weights were reduced by about 1 kg in all 3 groups. CONCLUSIONS: Lifestyle modification programs using group dynamics or using individual support by mail, in addition to individual behavioral support, appear to be effective for blood pressure reduction. Group counseling may be more effective in women.