Incidence of type-2 diabetes mellitus in a large population of Japanese male white-collar workers

Association between occupation type and development of type 2 diabetes: A population-based Panasonic cohort study 3

Background

Due to a lack of investigation on the association between the type of occupation and the development of type 2 diabetes among Japanese individuals, we aimed to assess this association in 98,935 Japanese individuals.

Methods

This long-term retrospective cohort study included participants selected from medical health checkup programs conducted at the Panasonic Corporation, Osaka, Japan, from 2008 to 2018. Cox regression analyses were used to evaluate the association between occupation type and the incidence of type 2 diabetes.

Results

From 2008 to 2018, 5,008 participants developed type 2 diabetes. The proportion of never smokers, those with slow eating speeds, and those working with a flextime system was higher in men with technical jobs than in salespersons, manufacturers, and office workers (p < 0.0001). Cox regression analyses revealed that occupation type was associated with an increased probability of type 2 diabetes development in men but not in women. Multivariate analyses showed that the hazard ratios were 1.15 [95% confidence interval (CI), 1.05-1.26], 1.20 (95% CI, 1.10-1.30), and 1.11 (95% CI, 1.02-1.21) in men working as salespersons, manufacturers, and office workers, respectively (reference group: men with technical jobs). On the other hand, the occupation type was not associated with the development of type 2 diabetes in women.

Conclusions

This study demonstrated that occupation type might be an independent factor in the development of type 2 diabetes in Japanese men.

Incidence of Diabetes in the Working Population in Spain: Results from the ICARIA Cohort

INTRODUCTION

Our objective was to evaluate the incidence of type 2 diabetes mellitus (T2DM) in a working population in Spain and to assess associations between its development and several risk factors.

METHODS

The ICARIA (Ibermutuamur CArdiovascular RIsk Assessment) cohort (n = 627,523) includes ~3% of Spanish workers. This analysis was undertaken in individuals whose glycaemic status during the index period (May 2004-December 2007) was determined to be normal or indicative of prediabetes [fasting plasma glucose (FPG) 100-125 mg/dl] and who had at least one FPG measurement taken 9 months after a first measurement during follow-up (May 2004-June 2014) (n = 380,366). T2DM patients were defined as those with an FPG ≥ 126 mg/day and those who had already been diagnosed with T2DM or were taking antihyperglycaemic medications.

RESULTS

The incidence rate of T2DM was 5.0 [95% confidence interval (CI) 4.9-5.1] cases per 1000 person-years. Under multivariate logistic regression analysis, the factor showing the strongest association with the occurrence of T2DM was the baseline FPG level, with the likelihood of T2DM almost doubling for every 5 mg/dl increase in baseline FPG between 100 and < 126 mg/dl. The presence of other cardiometabolic risk factors and being a blue-collar worker were also significantly associated with the occurrence of T2DM.

CONCLUSIONS

The incidence of T2DM in the working population was within the range encountered in the general population and prediabetes was found to be the strongest risk factor for the development of diabetes. The workplace is an appropriate and feasible setting for the assessment of easily measurable risk factors, such as the presence of prediabetes and other cardiometabolic factors, to facilitate the early detection of individuals at higher risk of diabetes and the implementation of diabetes prevention programmes.

FUNDING

Eli Lilly and Co.

Socioeconomic status and type 2 diabetes complications among young adult patients in Japan

Objective

To assess the relationship between socioeconomic status (SES) and complications of type 2 diabetes among young adults in Japan.

Design

A cross-sectional study.

Setting

Outpatient wards of 96 member hospitals and clinics of the Japan Federation of Democratic Medical Institutions.

Participants

A total of 782 outpatients with type 2 diabetes (525 males, 257 females), aged 20–40 years as of March 31, 2012. After excluding 110 participants whose retinopathy diagnosis was in question, 672 participants were analyzed.

Measurements

We examined the relations between SES (educational level, income, type of public healthcare insurance, and employment status) and diabetes complications (retinopathy and nephropathy) using a multivariate logistic regression analysis.

Results

The prevalence of type 2 diabetic retinopathy was 23.2%, while that of nephropathy was 8.9%. The odds of having retinopathy were higher among junior high school graduates (OR 1.91, 95% CI 1.09–3.34), patients receiving public assistance (OR 2.19, 95% CI 1.20–3.95), and patients with irregular (OR 1.72, 95% CI 1.03–2.86) or no employment (OR 2.23, 95% CI 1.36–3.68), compared to those with a higher SES, even after covariate adjustment (e.g., age, gender, body mass index). Similarly, the odds of having nephropathy were higher among patients with middle (OR 3.61, 95% CI 1.69–8.27) or low income levels (OR 2.53, 95% CI 1.11–6.07), even after covariate adjustment.

Conclusions

Low SES was associated with a greater likelihood of type 2 diabetes complications in young adults. These findings suggest the necessity of health policies that mitigate socioeconomic disparity and thereby reduce the prevalence of diabetic complications.

Impact of Diabetes Mellitus on Occupational Health Outcomes in Canada

Background:

Research suggests that diabetes mellitus (DM) has a negative impact on employment and workplace injury, but there is little data within the Canadian context.

Objective:

To determine if DM has an impact on various occupational health outcomes using the Canadian Community Health Survey (CCHS).

Methods:

CCHS data between 2001 and 2014 were used to assess the relationships between DM and various occupational health outcomes. The final sample size for the 14-year study period was 505 606, which represented 159 432 239 employed Canadians aged 15–75 years during this period.

Results:

We found significant associations between people with diabetes and their type of occupation (business, finance, administration: 2009, p=0.002; 2010, p=0.002; trades, transportation, equipment: 2008, p=0.025; 2011, p=0.002; primary industry, processing, manufacturing, utility: 2013, p=0.018), reasons for missing work (looking for work: 2001, p=0.024; school or education: 2003, p=0.04; family responsibilities: 2014, p=0.015; other reasons: 2001, p<0.001; 2003, p<0.001; 2010, p=0.015), the number of work days missed (2010, 3 days, p=0.033; 4 days, p=0.038; 11 days, p<0.001; 24 days, p<0.001), and workrelated injuries (traveling to and from work: 2014, p=0.003; working at a job or business: 2009, p=0.021; 2014, p=0.001).

Conclusion:

DM is associated with various occupational health outcomes, including workrelated injury, work loss productivity, and occupation type. This allows stakeholders to assess the impact of DM on health outcomes in workplace.

The relationship between physical activity levels and metabolic syndrome in male white-collar workers

[Purpose] Physical activity is important for preventing and managing metabolic syndrome. White-collar workers can be inherently predisposed to chronic diseases, as their jobs are primarily sedentary. The purpose of this study was to examine the relationship between physical activity and metabolic syndrome in male white-collar workers. [Subjects and Methods] Physical activity and metabolic syndrome factors were measured in 331 male public office workers. Physical activity was classified as high (N=101), moderate (N=115), or low (N=111) using the International Physical Activity Questionnaire. To diagnose metabolic syndrome, the U.S. National Cholesterol Education Program’s standard was used. [Results] Waist circumference and triglyceride levels, factors of metabolic syndrome, were significantly higher in the low physical activity group than in the moderate or high activity group. High-density lipoprotein cholesterol was significantly lower in the low physical activity group than in the moderate or high activity group. Waist circumference and fasting glucose were negatively correlated with physical activity level, and HDL cholesterol showed a positive correlation with waist circumference. The odds ratios for metabolic syndrome were 2.03 times higher (95% confidence interval, 1.01–4.09) in the low physical activity group than in the high physical activity group. [Conclusion] Low physical activity was a risk factor for metabolic syndrome in white-collar workers. Therefore, increasing physical activity in daily life may prevent metabolic syndrome in white-collar workers.

A new theory-based social classification in Japan and its validation using historically collected information

Studies of health inequalities in Japan have increased since the millennium. However, there remains a lack of an accepted theory-based classification to measure occupation-related social position for Japan. This study attempts to derive such a classification based on the National Statistics Socio-economic Classification in the UK. Using routinely collected data from the nationally representative Comprehensive Survey of the Living Conditions of People on Health and Welfare, the Japanese Socioeconomic Classification was derived using two variables - occupational group and employment status. Validation analyses were conducted using household income, home ownership, self-rated good or poor health, and Kessler 6 psychological distress (n ≈ 36,000). After adjustment for age, marital status, and area (prefecture), one step lower social class was associated with mean 16% (p < 0.001) lower income, and a risk ratio of 0.93 (p < 0.001) for home ownership. The probability of good health showed a trend in men and women (risk ratio 0.94 and 0.93, respectively, for one step lower social class, p < 0.001). The trend for poor health was significant in women (odds ratio 1.12, p < 0.001) but not in men. Kessler 6 psychological distress showed significant trends in men (risk ratio 1.03, p = 0.044) and in women (1.05, p = 0.004). We propose the Japanese Socioeconomic Classification, derived from basic occupational and employment status information, as a meaningful, theory-based and standard classification system suitable for monitoring occupation-related health inequalities in Japan.

Heart rate-corrected QT interval in resting ECG predicts the risk for development of type-2 diabetes mellitus

Chronic and subclinical sympathetic over-activity may underlie development of type-2 diabetes mellitus (DM). Since longer heart rate-corrected QT interval (QTc) represents predominance of sympathetic activity within autonomic balance, we investigated influences of QTc on the incidence of DM in a follow-up study. The subjects were 12,530 men and 7,163 women aged 30-59 years and apparently healthy at baseline. QTc in resting ECG was obtained using Bazett's formula (QTcB), Fridericia's formula (QTcF) and the linear regression technique (QTcLR). Incident DM was identified by 'fasting serum glucose > or =7.00 mmol l(-1) (126 mg dl(-1))' or/and 'on medication for DM'. Using Cox proportional hazard models, hazard ratio (HR) for incident DM was estimated according to the quartiles (Q1-Q4) of QTcB, QTcF or QTcLR, and its linear trends across the quartiles were checked. Baseline age, BMI, smoking, drinking, exercise and education were computed as conventional confounders. During the follow-up of 93,337 person-years for men and 51,517 person-years for women, 637 men and 192 women developed DM. The multivariate-adjusted HRs(95% confidence interval) for Q4 of QTcB, QTcF and QTcLR against corresponding Q1 were 1.85(1.46, 2.34), 1.31(1.04, 1.65) and 1.58(1.26, 1.99), respectively, for men, and 2.03(1.31, 3.16), 1.34(0.91, 2.00) and 1.58(1.04, 2.38), respectively, for women. Both sexes showed increasing trends in the HRs across the quartiles of QTcB, QTcF and QTcLR. In conclusion, QTc in resting ECG moderately but proportionally predicts the risk for development of DM in middle-aged healthy men and women. Moreover, the adverse effects of prolonged QTc are independent of those of conventional risk factors.

Resting heart rate and blood pressure, independent of each other, proportionally raise the risk for type-2 diabetes mellitus

BACKGROUND

Fast heart rate and high blood pressure (BP) at rest may raise risk for the development of type-2 diabetes mellitus (DM). We therefore investigated dose-response and interactive effects of resting heart rate and BP on the incidence of DM in a Japanese population.

METHODS

A follow-up study was conducted for 16 828 men and 8368 women aged 30-59 years and apparently healthy at baseline. Incident DM was identified by 'fasting serum glucose > or =7.00 mmol/l (126 mg/dl)' or/and 'under medical treatment for DM'. Using Cox proportional hazard models, hazard ratio (HR) for incident DM were estimated according to the quartiles of heart rate, systolic or diastolic BP (SBP, DBP), and its linear trends were checked by computing the three indices as continuous variables. Subsequently, interactive effects of slow/fast heart rate (dichotomized by the median) and low/high SBP or DBP (dichotomized by the median) on HR were examined. Baseline age, body mass index, smoking, drinking, exercise and education were computed as conventional confounders.

RESULTS

During the follow-up of 125 106 person-years for men and 59 616 person-years for women, 869 men and 224 women developed DM. The multivariate-adjusted HR for incident DM increased across quartiles of heart rate, SBP and DBP in both sexes (linear trend P<0.001 for all). Neither sex showed any significant interactive effects of heart rate and SBP or DBP on HR.

CONCLUSIONS

Resting heart rate and BP proportionally raise the risk for DM in middle-aged healthy men and women. Moreover, the adverse effects of fast heart rate and high BP are independent of each other as well as of the influences of conventional confounders.