Risk factors of recurrent sickness absence due to depression: a two-year cohort study among Japanese employees.

PURPOSE: Depression has a high recurrence rate among employees. There have been few studies investigating risk factors for recurrent sickness absence due to depression after return to work (RTW). The objective of this study was to identify potential risk factors. METHODS: Subjects were 540 full-time employees at the biggest telecommunication company in Japan who returned to work from April 2002 to March 2008 after their first leave of absence due to depression. The Cox proportional hazard model was employed to find risk factors for recurrent sickness absence by analyzing variables including demographic, work-related and work environmental factors. RESULTS: Of 540 study subjects, 200 employees (37.0 %) experienced recurrent sickness absence due to depression after RTW within the follow-up period. Higher organizational job demand evaluated by the Brief Job Stress Questionnaire (BJSQ) was found to be a risk factor (OR 1.46, 95 % CI 1.01-2.10) for recurrent sickness absence due to depression adjusted for confounding factors. CONCLUSIONS: High organizational job demand (evaluated by BJSQ) is a risk factor for recurrent sickness absence due to depression after RTW.

Long-term stable obesity increases risk of hypertension.

OBJECTIVES: Although some prospective cohort studies have shown that baseline BMI is positively associated with a future incident risk for hypertension, these studies do not account for weight changes during the observation period. Therefore, it is not evident whether future incident risk for hypertension in obese, non-hypertensive people increases when their weight remains stable. We examined the association between long-term weight stability and risk for developing hypertension. METHODS: A total of 5201 Japanese male workers aged 30-59 years underwent health checkups in 2002 and were followed through 2006. To consider transitions in covariates during the follow-up period, we used a time-dependent covariate Cox proportional hazard model to compute the relative risks (RRs) of incident hypertension. Furthermore, as a complementary analysis, we restricted the data to individuals whose BMI remained unchanged (± 5% of baseline BMI) during the follow-up and compared the RRs between BMI categories. RESULTS: During the follow-up, there were 899 newly diagnosed cases of hypertension among the 5201 men (14,888 person-years). Mean change in BMI during the follow-up period of all subjects was 0.2 ± 1.1 kg/m(2) (range: -6.6 to 6.3 kg/m(2)). The multivariate RRs for hypertension increased as BMI increased when we applied the time-dependent covariate Cox proportional hazard model. The complementary analysis showed that the multivariate RR (confidence interval) within the ≥ 27.0 kg/m(2) BMI category was 1.43 (1.16-1.77) times higher than the reference of 23.0-24.9 kg/m(2), whereas the RR for the <21.0 kg/m(2) BMI category was 0.63 (0.51-0.79) times lower than the reference. CONCLUSIONS: A higher baseline BMI increases future incident risk for hypertension even when there has been no major weight increase. Weight management should be encouraged for obese, non-hypertensive people to prevent future hypertension.

Gender difference of association between LDL cholesterol concentrations and mortality from coronary heart disease amongst Japanese: the Ibaraki Prefectural Health Study.

OBJECTIVE: The aim of this study was to examine whether LDL cholesterol raises the risk of coronary heart disease in a dose-response fashion in a population with low LDL-cholesterol levels. DESIGN: Population-based prospective cohort study in Japan. SUBJECTS AND MAIN OUTCOME MEASURES: A total of 30,802 men and 60,417 women, aged 40 to 79 years with no history of stroke or coronary heart disease, completed a baseline risk factor survey in 1993. Systematic mortality surveillance was performed through 2003 and 539 coronary heart disease deaths were identified. RESULTS: The mean values for LDL-cholesterol were 110.5 mg dL(-1) (2.86 mmol L(-1)) for men and 123.9 mg dL(-1) (3.20 mmol L(-1)) for women. Men with LDL-cholesterol > or =140 mg dL(-1) (> or =3.62 mmol L(-1)) had two-fold higher age-adjusted risk of mortality from coronary heart disease than did those with LDL-cholesterol <80 mg dL(-1) (<2.06 mmol L(-1)), whereas no such association for women was found. The multivariable hazard ratio for the highest versus lowest categories of LDL-cholesterol was 2.06 (95 percent confidence interval: 1.34 to 3.17) for men and 1.16 (0.64 to 2.12) for women. CONCLUSION: Higher concentrations of LDL-cholesterol were associated with an increased risk of mortality from coronary heart disease for men, but not for women, in a low cholesterol population.

Risk factors for chronic kidney disease in a community-based population: a 10-year follow-up study.

The purpose of this study was to explore risk factors affecting the incidence of chronic kidney disease (CKD) in general population. We conducted a 10-year follow-up study with 123 764 (male: 41 012, female: 82 752) adults aged 40 years and over who received community-based annual examinations. The primary outcome for the analysis was the development of CKD during the follow-up period. Predictors for the development of CKD were obtained by the significant hazard ratios (HR) in Cox regression model by sex. During the follow-up period, 4307 subjects (male: 2048, female: 2259) developed CKD stage I or II, and 19 411 subjects (male: 4257, female: 15 154) developed CKD stage III or higher. The baseline-adjusted predictor of developing CKD included age, glomerular filtration rate, hematuria, hypertension, diabetes, serum lipids, obesity, smoking status, and consumption of alcohol. Treated diabetes in male subjects, and treated hypertension, systolic blood pressure >160 mm Hg and/or diastolic blood pressure >100 mm Hg, diabetes, and treated diabetes in female subjects were associated with more than a doubling of the HR. For the development of CKD stage III or higher, proteinuria of >or= + +, and proteinuria and hematuria were associated with more than a doubling of the HR in male subjects. The prevalence of newly developed CKD over 10 years was 23 718 subjects (19.2%) in adults. This study suggested that not only hypertension and diabetes but also several metabolic abnormalities were independent risk factors for developing CKD.

The relationships of proteinuria, serum creatinine, glomerular filtration rate with cardiovascular disease mortality in Japanese general population.

Proteinuria, high serum creatinine, and reduced glomerular filtration rate (GFR) have been associated with increased mortality from cardiovascular disease (CVD) and all causes. However, the combined effect of proteinuria with serum creatinine and GFR on CVD or all-cause mortality has not been well investigated. We conducted a 10-year prospective cohort study of 30,764 men and 60,668 women aged 40-79 years who participated in annual health checkups in 1993. The Cox proportional hazards model was used to estimate the relative risk (RR) after adjusting for age, smoking, and other cardiovascular risk factors. The multivariable RR (95% confidence interval (CI)) of CVD death for positive vs negative proteinuria was 1.38 (1.05-1.79) among men and 2.15 (1.64-2.81) among women. The respective RR for the highest vs lowest creatinine groups (> or = 1.3 vs < or = 0.8 mg/dl for men and > or = 1.1 vs < or = 0.6 mg/dl for women) was 1.56 (1.19-2.04) among men and 2.15 (1.58-2.93) among women. The respective RR for GFR < 60 vs > r = 100 ml/min/1.73 m2 was 1.65 (1.25-2.18) among men and 1.81 (1.39-2.36) among women. For individuals with proteinuria combined by hypercreatininemia or reduced GFR, the risk of CVD death was two-fold higher in men and 4-6-fold higher in women compared to those without proteinuria and with normal creatinine level or GFR. Similar associations were observed for stroke, coronary heart disease, and all-cause mortality. Proteinuria, and hypercreatininemia or reduced GFR and their combination were significant predictors of CVD and all-cause mortality.

Factors affecting renal function in 119 985 adults over three years.

Blood pressure, proteinuria and serum creatinine (SCr) were examined in 119 985 adults, aged 40 years and older, who attended annual health examinations both in 1993 and 3 years later. Renal function was assessed from SCr; changes in individuals' renal function were estimated using the slope of the regression line for the reciprocal of the SCr level vs. time (slope of rSCr) over the 3-year period. Age-dependent SCr concentration increments were observed; however, there was no significant age-dependent change in the slope of rSCr. SCr in hypertensives on anti-hypertensive medication was significantly higher than that in untreated hypertensives, borderline hypertensives and normotensives. The slopes of rSCr in hypertensives (treated, untreated and borderline) were steeper than normotensives in males, and that in untreated hypertensives was steeper than other groups in females. In hypertensives with proteinuria, SCr was higher and renal function deteriorated more rapidly, compared with hypertensives without proteinuria. Hypertension with proteinuria appears to be an important indicator for progressive decline in renal function, this trend being more obvious in males. Renal function decreases with age; however, the rate of decline is constant. The influences of proteinuria and blood pressure on renal function are different in males and females.

[Prediction of mortality from findings of annual health checkups utility for health care programs].

OBJECT: To clarify relationships between the findings of annual health checkups and mortality in men and women living in Ibaraki prefecture. METHOD: The subjects were 32,705 men and 63,959 women aged 40 to 79 years who participated in annual health checkups in 1993. They were followed up until November 30, 1998, with a systemic review of resident registration and death certificates. The Cox's proportional hazards model was used to estimate relative risk, after adjustment for age, smoking status, usual alcohol intake, hypertension category, serum total cholesterol, HDL cholesterol, blood glucose, serum creatinine, body mass index (BMI) and urinary protein. RESULTS: During the 5.2-year follow-up, there were 2,937 deaths (including 384 deaths from stroke, 242 from coronary heart disease and 1,305 from cancer). Significant predictors of mortality from all causes were smoking, usual alcohol intake, hypertension, low serum total cholesterol, low BMI, high blood glucose level, proteinuria for men and women, and low HDL cholesterol for men, and high serum creatinine for women. Significant predictors of mortality from all cardiovascular diseases were smoking, hypertension, low BMI, high serum creatinine, proteinuria for men and women, usual alcohol intake and low HDL cholesterol for men, and serum total cholesterol and high blood glucose level for women. Significant predictors of mortality from stroke were hypertension, low BMI, high serum creatinine for men and women, and proteinuria for women. Significant predictors of mortality from coronary heart disease were smoking, high serum total cholesterol, high blood glucose level, proteinuria for men and women, hypertension, low HDL cholesterol for men. Significant predictors of mortality from cancer were smoking, usual alcohol intake, BMI for men and women, low serum total cholesterol, low HDL cholesterol and proteinuria for men, and high blood glucose level for women. Smoking, usual alcohol intake, low HDL cholesterol and proteinuria were significant predictors of mortality from lung cancer for men. CONCLUSION: Smoking, usual alcohol intake, hypertension, BMI, serum level of total cholesterol, HDL cholesterol, blood glucose, creatinine, and urinary protein are significantly associated with mortality. We obtained the new finding that serum creatinine level is a significant predictor of mortality from all cardiovascular diseases in Japanese men and women, and that the multivariate relative risk in female moderate alcohol drinkers (46-68 g ethanol intake/day) vs non-drinkers is significantly elevated for death from all causes. The results of our study are useful for planning of health care education and services.

[Yearly changes and geographical distribution of allergic rhinitis morbidity estimated from records of the national health insurance].

The age-adjusted morbidity of allergic rhinitis (AR) in Ibaraki prefecture in May, estimated from data of national health insurance records, increased remarkably from 1980 to 1992 with varying yearly rates of increase. High AR morbidity years coincided with years of high Japanese cedar and cypress pollen counts, and moreover, an estimate equation of the morbidity using as explanatory variables, year and the yearly total count of pollen, accurately estimated AR morbidity. The AR morbidity varied with the size of the municipality. The AR morbidity of the town group and village group were about 80% and about 60% respectively of the city group in 1992. The map of the AR morbidity of each municipality showed that urbanized districts had higher morbidity than areas with cedar forests, which are supposedly sources of the cedar pollen. Continuous increase of morbidity of districts with much cedar forests terminated in 1986. Since then only the fluctuation of the morbidity corresponding to the pollen count was observed. The ratio of the morbidity of the years with much pollen to that of the years with little pollen was mapped. The map showed good agreement with the map of cedar forests. The results obtained above demonstrate the usefulness of the data of the national health insurance records.