Targeting Abdominal Adiposity and Cardiorespiratory Fitness in the Workplace

Leisure-time physical activity is more strongly associated with cardiometabolic risk than occupational physical activity: Results from a workplace lifestyle modification program

BACKGROUND

Regular physical activity (PA) plays a key role in the management and prevention of numerous chronic diseases. However, recent studies have suggested that occupational physical activity (OPA) may not always have health benefits. The aim of the present study was to examine the respective contributions of OPA vs. leisure-time physical activity (LTPA) to the variation in the cardiometabolic profile, including cardiorespiratory fitness (CRF), of employees involved in a workplace lifestyle modification program. Our study hypothesis was that LTPA would show a stronger association with indices of cardiometabolic health than OPA.

METHODS

A mobile health assessment unit was used to assess 5145 workers (3397 men and 1748 women) on site at their workplace. Assessments included lifestyle questionnaires (overall diet quality, type of OPA and level of LTPA), blood pressure measurements, blood tests, anthropometric measurements, and a submaximal treadmill exercise test to assess CRF. Results were adjusted for education, household income and age.

RESULTS

When workers were classified on the basis of their OPA (sedentary work, standing work, physical work, and heavy manual work), only a few significant differences in the cardiometabolic profile were observed in men, with those in the physical work category having more favorable values than sedentary workers. However, substantial and significant differences were observed among employees classified on the basis of their LTPA, these differences being observed in both men and women. For instance, waist circumference, the cholesterol/HDL cholesterol ratio, triglyceride concentrations and resting heart rate were lower in active individuals compared to inactive and moderately inactive individuals (p < 0.01). Furthermore, irrespective of whether or not employees were sedentary at work, a high level of LTPA was associated with a greater CRF (p < 0.001). Finally, we found that the lowest prevalence of hypertriglyceridemic waist (p < 0.01) and the highest score of overall diet quality (p < 0.001) were observed in active individuals, irrespective of their OPA category.

CONCLUSION

Levels of LTPA were more strongly associated with cardiometabolic health than OPA in a cohort of blue- and white-collar employees. Furthermore, high levels of LTPA were found to counteract the potentially deleterious effects of a sedentary work on cardiometabolic health.

Targeting Diet Quality at the Workplace: Influence on Cardiometabolic Risk

The American Heart Association criteria for cardiovascular health include overall diet quality (DQ). The present study evaluated the effect of a workplace health promotion program targeting DQ and physical activity on features of cardiometabolic risk (CMR). Before and after the 3-month intervention, 2260 employees (1462 men and 798 women) completed a health and fitness evaluation including assessment of DQ using a validated food-based questionnaire. After the 3-month lifestyle modification program, DQ increased significantly in both sexes (p < 0.0001) as well as physical activity level (p < 0.0001). A reduction in waist circumference (p < 0.0001) and improved lipid levels were also observed. Significant associations were found between changes in DQ index and changes in CMR variables in both men (standardized regression coefficients ranged from −0.19 (95% confidence interval: −0.26 to −0.12) to −0.29 (95% confidence interval: −0.34 to −0.25)) and women (standardized regression coefficients ranged from −0.18 (95% confidence interval: −0.25 to −0.11) to −0.27 (95% confidence interval: −0.41 to −0.13)). Multiple linear regression analyses showed a significant contribution of changes in the DQ index to the variation in some CMR variables, independent from changes in physical activity level and cardiorespiratory fitness. This study provides evidence that targeting DQ at the workplace is relevant to improve cardiometabolic health.

Deteriorated Cardiometabolic Risk Profile in Individuals With Excessive Blood Pressure Response to Submaximal Exercise

BACKGROUND

Early identification of individuals at increased cardiometabolic risk is an essential step to improve primary preventive interventions. Excessive maximal exercise blood pressure (EBP) has been associated with several adverse outcomes. We examined how submaximal EBP could help us to identify individuals with a deteriorated cardiometabolic risk profile.

METHODS

Data from an observational study of 3,913 participants from a convenience sample were used. Subjects included in the analyses completed a comprehensive cardiometabolic health assessment (resting blood pressure [BP]; waist circumference; lipid profile; HbA1c; submaximal treadmill exercise test including a standardized stage [3.5 mph and 2% slope] with BP and heart rate measurements). Participants were classified on BP response at the standardized stage (Normal or Excessive Response). Excessive response was defined as systolic BP ≥ 80th percentile or diastolic BP ≥ 90 mmHg. Subjects were also classified into five resting BP subgroups according to current guidelines.

RESULTS

The Excessive Response group had more deteriorated cardiometabolic and cardiorespiratory profiles than the Normal Response group (P ≤ 0.01). The Excessive Response group also showed a greater proportion of carriers of the hypertriglyceridemic waist phenotype in most resting BP subgroups (P ≤ 0.05). Finally, excessive BP response to submaximal exercise showed an independent contribution on cardiometabolic and cardiorespiratory factors beyond age, sex, and resting BP.

CONCLUSIONS

This study demonstrates that an excessive BP response to a submaximal exercise is associated with a deteriorated cardiometabolic risk profile beyond resting BP profile. Therefore, submaximal EBP represents a simple screening tool to better identify at-risk individuals requiring aggressive preventive lifestyle interventions.

From syndrome X to cardiometabolic risk: clinical and public health implications

Although the first description of a syndrome defined by the co-existence of atherogenic and diabetogenic metabolic abnormalities is debated in the literature, it was Gerald Reaven who proposed, in his landmark 1988 Banting award lecture, that a significant proportion of individuals (with diabetes or not) were characterised by insulin resistance causing prejudice to cardiovascular health. However, Reaven was influenced by seminal observations made more than 50 years earlier by Himsworth who proposed that there were two forms of diabetes (insulin resistant v. insulin sensitive). Reaven went further in proposing the theory that insulin resistance was the most prevalent cause of CVD associated with metabolic abnormalities that he named syndrome X. Because there was a syndrome X documented in cardiology, the term evolved to insulin resistance syndrome. As Reaven could also find insulin-resistant individuals in non-obese subjects, he did not include obesity as a feature of syndrome X. Imaging studies then revealed that excess adipose tissue in the abdominal cavity, a condition described as visceral obesity, was the form of overweight/obesity associated with insulin resistance and its related abnormalities. As obesity risk assessment and management remain largely based on body weight (BMI) and weight loss, it is proposed that our clinical approaches and public health messages should be revisited. First, patients should be educated about the importance of monitoring their waistline as a crude index of abdominal adiposity. Secondly, public health approaches focussing on 'lifestyle vital signs' including achieving healthy waistlines rather than healthy body weights should be developed.

Assessing nutritional quality as a 'vital sign' of cardiometabolic health

High overall nutritional quality (NQ) is an important component of ideal cardiovascular health, a concept introduced in 2010 by the American Heart Association. However, data on the independent contribution of overall NQ to the variation in the cardiometabolic risk (CMR) profile are limited. This observational study aimed to investigate the association between overall NQ and the CMR profile in 4785 participants (65⋅4 % of men, age 43⋅3 (sd 10⋅8) years) who underwent a cardiometabolic health evaluation, including lifestyle habits, anthropometric measurements, blood pressure, lipid profile and HbA1c concentrations. In addition, a submaximal exercise test was conducted to assess cardiorespiratory fitness (CRF). Using a standardised NQ questionnaire (twenty-five items food-based questionnaire), participants were classified into three subgroups: (1) low, (2) moderate or (3) high NQ and variance and multiple linear regression analyses were performed. Results showed that less than 15 % of participants presented a high NQ. A high NQ was associated with a healthier lifestyle habits and a more favourable CMR profile (lower values of waist circumference and cholesterol:HDL-cholesterol ratio, lower concentrations of non-HDL-cholesterol, TAG and HbA1c). Some of these associations were independent of age, physical activity level (PAL) and CRF. A better NQ was also associated with a lower proportion of participants presenting the hypertriacylglycerolaemic waist phenotype independently of both PAL and CRF. The present study suggests that overall NQ can be assessed with a short food-based questionnaire and should be considered in clinical practice as a new 'vital sign' associated with other health behaviours and cardiometabolic health.

Relation Between a Simple Lifestyle Risk Score and Established Biological Risk Factors for Cardiovascular Disease

Although cardiovascular disease (CVD) and diabetes mellitus are largely lifestyle driven, lifestyle metrics are not used in clinical practice. This study examined the relevance of using a simple lifestyle risk score designed for primary care medicine by testing its ability to predict biological CVD risk factors in a cohort of 3,712 individuals involved in a workplace health evaluation or management program ("Grand Défi Entreprise" project). Using a lifestyle risk score based on waist circumference, fitness, nutritional quality, and physical activity level, employees were categorized into 3 distinct estimated lifestyle risk levels (low, intermediate, and high). A biological CVD risk score was also calculated, which included high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), cholesterol-to-HDL-C ratio, blood pressure, hemoglobin glycated levels, and medication use. Diastolic blood pressure, TG levels, and the cholesterol-to-HDL-C ratio increased across categories of lifestyle risk score, whereas HDL-C decreased (p <0.05). Calculated Framingham and diabetes risk scores as well as the prevalence of hypertriglyceridemic waist phenotype also increased across categories of lifestyle risk score (p <0.05). Finally, 1-way analysis of variance revealed that the biological risk score significantly increased across the lifestyle risk score categories (p <0.0001). Our study provides evidence that lifestyle variables can be measured and targeted in clinical practice.

Cardiorespiratory fitness testing and cardiovascular disease risk in male steelworkers

BACKGROUND

The workplace has been advocated as a setting to perform cardiovascular disease (CVD) risk assessments. These risk assessments usually focus on traditional risk factors rather than cardiorespiratory fitness (CRF) despite established associations between CRF and CVD. The lack of guidance on interpreting health-related CRF values has been suggested as a barrier to utilizing CRF in practice.

AIMS

To assess the merits of CRF testing in the workplace and explore whether a CRF value identified male individuals above the recommended threshold for further clinical investigation.

METHODS

Cross-sectional analysis of male steelworkers from Carmarthenshire, South Wales, UK who completed a workplace-based CVD risk assessment with an added CRF protocol based on heart rate responses (Chester Step Test). Receiver operating characteristic (ROC) analysis was undertaken to explore the possibility of a CRF value to identify individuals at an increased 10-year risk of CVD (QRISK2 ≥ 10%).

RESULTS

There were 81 participants. ROC analysis revealed that a CRF level of 34.5ml/kg/min identified those individuals above the ≥10% QRISK2 threshold with the best sensitivity (0.800) and specificity (0.687) to discriminate against true- and false-positive rates. Further analysis revealed that individuals with either 'Average' or 'Below Average' CRF would be five times more likely to have a 10-year CVD risk above the ≥10% QRISK2 threshold than individuals with an 'Excellent' or 'Good' level of fitness [OR 5.10 (95% CI 1.60-16.3)].

CONCLUSIONS

This study suggests CRF assessments are a useful addition to a workplace CVD assessment and could identify male individuals at increased predicted risk of the condition.

Impact of a Workplace Health Promotion Program on Employees' Blood Pressure in a Public University

INTRODUCTION

Workplace health promotion is important in the prevention of non-communicable diseases among employees. Previous workplace health programs have shown benefits such as lowered disease prevalence, reduced medical costs and improved productivity. This study aims to evaluate the impact of a 6-year workplace health promotion program on employees' blood pressure in a public university.

METHODS

In this prospective cohort study, we included 1,365 employees enrolled in the university's workplace health promotion program, a program conducted since 2008 and using data from the 2008-2013 follow-up period. Participants were permanent employees aged 35 years and above, with at least one follow up measurements and no change in antihypertensive medication during the study period. Baseline socio-demographic information was collected using a questionnaire while anthropometry measurements and resting blood pressure were collected during annual health screening. Changes in blood pressure over time were analyzed using a linear mixed model.

RESULTS

The systolic blood pressure in the hypertension subgroup decreased 2.36 mmHg per year (p<0.0001). There was also significant improvement in systolic blood pressure among the participants who were at risk of hypertension (-0.75 mmHg, p<0.001). The diastolic blood pressure among the hypertensive and at risk subgroups improved 1.76 mmHg/year (p<0.001) and 0.56 mmHg/year (p<0.001), respectively. However, there was no change in both systolic and diastolic blood pressure among participants in the healthy subgroup over the 6-year period.

CONCLUSION

This study shows that continuing participation in workplace health promotion program has the potential to improve blood pressure levels among employees.

Assessing and targeting key lifestyle cardiovascular risk factors at the workplace: Effect on hemoglobin A1c levels

PURPOSE

Despite the key role played by lifestyle habits in the epidemic of type 2 diabetes (T2D), nutritional quality and physical activity are not systematically considered in clinical practice. The project was conducted to verify whether assessing/targeting lifestyle habits could reduce hemoglobin A1c (HbA1c) levels of employees.

METHODS

The intervention consisted of a 3-month competition among teams of five employees to favor peer-based support in the adoption of healthier lifestyle habits (Eat better, Move more, and Quit smoking) (n = 900). A comprehensive cardiometabolic/cardiorespiratory health assessment was conducted before and after the contest (nutrition/physical activity questionnaires, blood pressure, anthropometric measurements, lipid profile, HbA1c, fitness). HbA1c levels were used to identify individuals with prediabetes (5.7%-6.4%) or T2D (≥6.5%).

RESULTS

At baseline, 51% of the employees had increased HbA1c levels (≥5.7%). The HbA1c levels were associated with waist circumference, independently of body mass index. Subjects with prediabetes showed a higher waist circumference as well as a more deteriorated cardiometabolic profile compared to workers with normal HbA1c levels. After the intervention, employees with elevated HbA1c significantly reduced their HbA1c levels.

CONCLUSION

Results suggest that assessing/targeting key lifestyle correlates of the cardiometabolic profile represents a relevant approach to target abdominal obesity and fitness with a significant impact on HbA1c levels.