Obesity indices are predictive of elevated C-reactive protein in long-haul truck drivers

Retrospective quality review of Department of Transportation (DOT) commercial drivers medical examination forms

OBJECTIVE

This study aimed to evaluate the quality of completion among both drivers and medical examiners in filling out Commercial Driver's (CD) Medical Examination Report Forms.

METHODS

This was a cross-sectional retrospective study of abstracted data from the year 2019. CD Medical Examination Report Forms, collected from a single nationally-based employer and initially reviewed by corporate medical directors, were evaluated by the study team for completeness of documentation provided by both drivers and medical examiners (MEs). Relevant findings included unanswered questions, inconsistency between responses, and lack of necessary elaboration for positive responses.

RESULTS

Among 1603 examinations, MEs completed the Medical Examination Report Form incompletely or incorrectly in 30% of examinations (n = 484). Drivers inconsistently filled out their health history with elaborations 38.7% of the time. Most commonly, they failed to elaborate on positive health history responses in 28.7% of examinations, but other types of errors were noted as well.

CONCLUSIONS

A considerable proportion of drivers or examiners (n = 890, 55%) failed to adequately or correctly complete CD Medical Examination Report forms.

Inflammatory diets are associated with lower total iron binding capacity in sera of young adults

Chronic, systemic inflammation, which is associated with obesity and numerous other diseases, impairs iron status by increasing hepcidin concentration. Inflammation also decreases the concentration of transferrin, the main iron transport protein and a negative acute phase protein, which is indirectly assessed by measuring total iron binding capacity (TIBC). However, the contribution of diet-induced inflammation has not been studied. Data from two studies, namely Diet and Inflammation and Selenium and Inflammation Studies (total n=98) were used to assess the associations among Dietary Inflammatory Index (DII^®) scores derived from three-day dietary records, body mass index (BMI=weight[kg]/height[m]²), inflammatory and hematological markers among young adults with normal-weight, overweight or obesity. Subjects' diets were also categorized as less inflammatory diets (LID) and inflammatory diets (ID) using cluster analysis. Independent t-test and regression analyses were used to assess associations in the data. Intakes of iron, proteins, fat, fiber, and calories were higher in the LID group compared to the ID group (p<0.05). Demographic characteristics and concentrations of C-reactive protein (CRP) and iron status biomarkers did not differ significantly between the two groups (p>0.05). Higher DII score was associated with increasing CRP (β+SE=0.23+0.07, p=0.002) and lower TIBC (β+SE=-8.46+3.44, p=0.02), independent of BMI category. The LID diet was associated with higher TIBC (β+SE=29.87+10.75, p=0.007) compared to the ID diet. In conclusion, inflammatory diets may impair iron status by reducing the iron binding capacity of transferrin.

A Retrospective Medical Record Review to Describe Health Status and Cardiovascular Disease Risk Factors of Bus Drivers in South Africa

Cardiovascular disease (CVD) is the leading cause of death globally. The occupational challenges of bus drivers may increase their risk of CVD, including developing obesity, hypertension, and diabetes. We evaluated the medical records of 266 bus drivers visiting an occupational medical practice between 2007 and 2017 in Johannesburg, South Africa, to determine the health status of bus drivers and investigate risk factors for CVD, and their impact on the ability to work. The participants were in majority male (99.3%) with a median age of 41.2 years (IQR 35.2); 23.7% were smokers, and 27.1% consumed alcohol. The median body mass index (BMI) was 26.8 m/kg² (IQR 7.1), with 63.1% of participants having above normal BMI. Smoking, BMI, and hypertension findings were in line with national South African data, but diabetes prevalence was far lower. Undiagnosed hypertension was found in 9.4% of participants, uncontrolled hypertension in 5.6%, and diabetes in 3.0%. Analysis by BMI category found that obesity was significantly associated with increased odds of hypertension. Uncontrolled hypertension was the main reason for being deemed 'unfit to work' (35.3%). Our research highlights the need for more regular screening for hypertension and interventions to address high BMI.

Work, physical activity, and metabolic health: Understanding insulin sensitivity of long-haul truck drivers

BACKGROUND

Long-haul truck drivers are disproportionately exposed to metabolic risk; however, little is known about their metabolic health and the role of physical activity and other risk factors in metabolic outcomes.

OBJECTIVE

This study compares truck drivers' insulin sensitivity, and associations between metabolic risk factors and insulin sensitivity, with those of the general population.

METHODS

Survey, anthropometric, and biometric data were collected from 115 long-haul truckers, which were then compared to the general population data using the National Health and Nutrition Examination Survey (NHANES) dataset. The quantitative insulin sensitivity check index (QUICKI) was used to estimate insulin sensitivity.

RESULTS

Truck drivers had lower QUICKI scores than the general population cohort. Sagittal abdominal diameter and exercise were predictive for QUICKI among combined cohorts. Waist circumference and perceived health were more predictive for QUICKI among truck drivers, and sagittal abdominal diameter and income were more predictive for QUICKI among the general population.

CONCLUSIONS

Long-haul truckers appear to represent a subset of the general population regarding the impact of physical activity and other metabolic risk factors on QUICKI. Accordingly, comprehensive efforts which target these factors are needed to improve truckers' physical activity levels and other metabolic risks.

Cardiometabolic risk factors and mental health status among truck drivers: a systematic review

OBJECTIVE

This study aimed to systematically review and summarise the literature on cardiometabolic risk factors, lifestyle health behaviours and mental health status of truck drivers globally to ascertain the scale of these health concerns.

DESIGN

Systematic review reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

DATA SOURCES

PubMed, Scopus, PsycINFO and Web of Science were searched in January 2019 and updated in January 2020, from the date of inception to 16 January 2020.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Papers were included if they (1) reported independent data on truck drivers, (2) included quantitative data on outcomes related to cardiometabolic markers of health, mental health and/or health behaviours, (3) were written in English and (4) were published in a peer-reviewed journal. Grey literature was ineligible for this review.

DATA EXTRACTION AND SYNTHESIS

One reviewer independently extracted data and assessed methodological quality using a checklist based on the National Heart, Lung and Blood Institute Quality Assessment tool. 20% were independently assessed for eligibility and quality by a second reviewer. Due to heterogeneity of the outcomes, results were narratively presented.

RESULTS

3601 titles and abstracts were screened. Seventy-three studies met the inclusion criteria. Truck driving is associated with enforced sedentarism, long and irregular working hours, lack of healthy foods, social isolation and chronic time pressures. Strong evidence was observed for truck drivers to generally exhibit poor cardiometabolic risk profiles including overweight and obesity, hypertension, hypercholesterolaemia, high blood glucose, poor mental health and cigarette smoking.

CONCLUSIONS

Improving truck driver health is vital for the longevity of the trucking industry, and for the safety of all road users. The workplace plays a vital role in truck driver health; policies, regulations and procedures are required to address this health crisis.

PROSPERO REGISTRATION NUMBER

CRD42019124499.

Clinical epidemiology studies on potential effects of endocrine disrupting chemicals (EDCs) should exclude subjects with obesity as determined by BMI

Obesity as determined by BMI is a confounder in clinical evaluations of the effects of endocrine disrupting chemicals (EDCs). Validated regulatory tests are used to determine whether a chemical acts via a mode of action (MOA) that affects estrogen, androgen, thyroid or steroidogenic pathways. Test batteries for evaluating EDCs include QSAR, in vitro assays, and animal testing. Studies suggest that EDCs pose the greatest risk during prenatal and early infant development when organ systems are developing. Health effects include lowered fertility, endometriosis, and cancers associated with estrogenic activity. Epidemiology studies on adverse effects of EDCs in the general population are difficult to conduct due to very low exposures of EDCs in non-occupational cohorts, and lack of exposure measurements between cases and controls. In contrast with very low levels of hormonal perturbation from nano-molar to micro-molar exposures to EDCs, adipose tissue in obesity alters estrogen, testosterone, thyroid stimulating hormone, and inflammation levels. Obesity in pregnancy and gestational diabetes are associated with adverse outcomes in infants and children including autism, poor motor skills, lowered IQ, and altered birth weight. Neonatal effects of obesity are confounded by average lower socio-economic status. The already perturbed endocrine balance in overweight or obese persons renders them particularly worthy subjects for clinical epidemiology investigations on the possible effects of endocrine disrupting chemicals. However, inclusion of subjects with obesity requires accounting for potentially confounding effects of the hormonal influences arising from excess adiposity. If subjects with obesity are to be included in clinical epidemiological evaluations related to hormonal effects, the subjects should be classified by body fat percentage rather than by the much less exact measure of body mass index (BMI).

Exposure to chemicals formed from natural processes is ubiquitous

Exposure to chemicals produced by natural processes is ubiquitous. First, in addition to the products of normal metabolism produced in humans of normal body weight, adipose tissue produces a large number of chemicals, including estrogen, testosterone from the produced estrogen, thyroid-stimulating hormone, leptin and approximately 500 other molecules termed adipokines, and a large number of inflammatory mediators. Second, the gut biome contains approximately the same number of bacteria as cells found in the entire body and produces a large number of small molecules. Third, the overwhelming majority (99.9%) of pesticide exposure occurs during ingestion of natural plant pesticides from eating vegetables. Fourth, consumption of cooked muscles meats leads to significant exposure to mutagenic and carcinogenic heterocyclic amines, polycyclic aromatic amines, and nitropyrenes. Fifth, many common beverages, for example, beer, coffee, and tea contain organic chemicals that display mutagenic activity. As compared with man-made production levels, from 1945 to 2015, an estimated 5000-fold more organic compounds were produced by a variety of natural processes, including common wood-degrading and forest litter-degrading fungi, microorganisms in temperate and boreal forest soils, bacteria in marine sponges, marine macro-algae, volcanoes, and forest fires. Exposure to these naturally produced organic compounds occurs via inhalation of ambient air, ingestion of food and water, and contact with soil, freshwater, and seawater. Contact with several thousand different endogenous or exogenous chemicals per day is unavoidable. This understanding might assist in better allocating resources toward controlling exposures to agents of highest concern as determined by current concepts of chronic disease causation.

Sleep for heart health: investigating the relationship between work day sleep, days off sleep, and cardiovascular risk in Australian train drivers

Cardiovascular disease (CVD) risk in train drivers is associated with health conditions that can result in sudden incapacity. Drivers are at high risk on several CVD risk factors with research suggesting that sleep may predict CVD risk, however this relationship has not yet been explored. This study investigated the link between sleep and CVD risk, in relation to hours of work day and days off sleep. N=309 Australian drivers completed a cross-sectional survey. A CVD risk score was calculated by summing scores from behavioural and biomedical risk factors. Sleep was most frequently cited as the main reason for decline in perceived health status. Main analyses showed that shorter work day sleep (M=5.79 h) was a significant predictor of increased CVD risk (p=0.013). This relationship was moderated by days off sleep, such that when days off sleep (M=8.17 h) was higher, the effect of work day sleep on CVD risk was weaker (p=0.047). Findings indicate the amount of sleep a driver obtains on non-work days may compensate for adverse health outcomes. Successful management of fatigue in safety critical occupations appears essential not only for the prevention of safety hazards, but also for the long-term health of shift workers. Further investigation is warranted.

Can subjective sleep problems detect latent sleep disorders among commercial drivers?

INTRODUCTION

Long-haul truck drivers experience poor sleep health and heightened accident rates, and undiagnosed sleep disorders contribute to these negative outcomes. Subjective sleep disorder screening tools may aid in detecting drivers' sleep disorders. This study sought to evaluate the value of subjective screening methods for detecting latent sleep disorders and identifying truck drivers at-risk for poor sleep health and safety-relevant performance.

MATERIALS AND METHODS

Using cross-sectional data from 260 long-haul truck drivers, we: 1) used factor analysis to identify possible latent sleep disorders; 2) explored the construct validity of extracted sleep disorder factors by determining their associations with established sleep disorder risk factors and symptoms; and 3) explored the predictive validity of resulting sleep disorder factors by determining their associations with sleep health and safety-relevant performance.

RESULTS

Five latent sleep disorder factors were extracted: 1) circadian rhythm sleep disorders; 2) sleep-related breathing disorders; 3) parasomnias; 4) insomnias; 5) and sleep-related movement disorders. Patterns of associations between these factors generally corresponded with known risk factors and symptoms. One or more of the extracted latent sleep disorder factors were significantly associated with all the sleep health and safety outcomes.

DISCUSSION

Using subjective sleep problems to detect latent sleep disorders among long-haul truck drivers may be a timely and effective way to screen this highly mobile occupational segment. This approach should constitute one component of comprehensive efforts to diagnose and treat sleep disorders among commercial transport operators.

A retrospective analysis of cardiometabolic health in a large cohort of truck drivers compared to the American working population

BACKGROUND

Truck drivers face many health challenges, including lifestyle, diet, inactivity, stressors, and social support.

METHODS

A repeated cross-sectional analysis compared 88,246 truck drivers with data from (n = 11 918) the National Health and Nutrition Examination Survey (NHANES). Trends over time for body mass index (BMI), high blood pressure, diabetes mellitus, heart disease, and sleep disorders were analyzed, adjusting for potential confounders.

RESULTS

Truck drivers had significantly worsening health metrics between 2005 and 2012 compared to NHANES participants. Truck drivers were significantly more likely to be obese and morbidly obese with prevalence odds ratios (POR) and 95% confidence intervals (95%CI) of 1.99 (1.87, 2.13) and 2.34 (2.16, 2.54), respectively. Measured blood pressure, self-reported high blood pressure, diabetes mellitus, and heart disease all significantly increased. Also, sleep disorders increased among truck drivers from 2005 to 2012 (POR = 6.55, 95%CI 5.68, 7.55).

CONCLUSION

These data suggest disproportionate increases in poor health among truck drivers from 2005 to 2012.

Is the Relationship between Depression and C Reactive Protein Level Moderated by Social Support in Elderly?-Korean Social Life, Health, and Aging Project (KSHAP)

OBJECTIVE

To investigate the buffering effects of social support as an effects modifier in the association between depression and inflammation in the elderly.

METHODS

We analyzed the Korean Social Life, Health, and Aging Project (KSHAP) for questionnaire, clinical, and laboratory data of 530 older adults living in a rural community. Multivariate regression models were used to investigate the association between depressive symptoms and C-reactive protein level (CRP), a marker of inflammation, at varying levels of social support.

RESULTS

Social support affected the association between depressive symptoms and CRP level in both sexes. However, the direction of effects modification was different for men and women. In men, a higher CRP level was significantly associated with depressive symptoms only among those with lower support from a spouse or family members. By contrast, in women, the association was significant only among subgroups with higher spousal or family support. Social support from neighbors or friends did not affect the depression-inflammation relationship in men but modestly affected the relationship in women.

CONCLUSION

Our findings suggest that social support may have a buffering effect in the relationship between depression and inflammation in elderly Koreans. But the influence of social support may run in different directions for men and women.

Work, sleep, and cholesterol levels of U.S. long-haul truck drivers

Long-haul truck drivers in the United States experience elevated cardiovascular health risks, possibly due to hypercholesterolemia. The current study has two objectives: 1) to generate a cholesterol profile for U.S. long-haul truck drivers; and 2) to determine the influence of work organization characteristics and sleep quality and duration on cholesterol levels of long-haul truck drivers. Survey and biometric data were collected from 262 long-haul truck drivers. Descriptive analyses were performed for demographic, work organization, sleep, and cholesterol measures. Linear regression and ordinal logistic regression analyses were conducted to examine for possible predictive relationships between demographic, work organization, and sleep variables, and cholesterol outcomes. The majority (66.4%) of drivers had a low HDL (<40 mg/dL), and nearly 42% of drivers had a high-risk total cholesterol to HDL cholesterol ratio. Sleep quality was associated with HDL, LDL, and total cholesterol, and daily work hours were associated with LDL cholesterol. Workday sleep duration was associated with non-HDL cholesterol, and driving experience and sleep quality were associated with cholesterol ratio. Long-haul truck drivers have a high risk cholesterol profile, and sleep quality and work organization factors may induce these cholesterol outcomes. Targeted worksite health promotion programs are needed to curb these atherosclerotic risks.

Understanding the role of sleep quality and sleep duration in commercial driving safety

INTRODUCTION

Long-haul truck drivers in the United States suffer disproportionately high injury rates. Sleep is a critical factor in these outcomes, contributing to fatigue and degrading multiple aspects of safety-relevant performance. Both sleep duration and sleep quality are often compromised among truck drivers; however, much of the efforts to combat fatigue focus on sleep duration rather than sleep quality. Thus, the current study has two objectives: (1) to determine the degree to which sleep impacts safety-relevant performance among long-haul truck drivers; and (2) to evaluate workday and non-workday sleep quality and duration as predictors of drivers' safety-relevant performance.

MATERIALS AND METHODS

A non-experimental, descriptive, cross-sectional design was employed to collect survey and biometric data from 260 long-haul truck drivers. The Trucker Sleep Disorders Survey was developed to assess sleep duration and quality, the impact of sleep on job performance and accident risk, and other relevant work organization characteristics. Descriptive statistics assessed work organization variables, sleep duration and quality, and frequency of engaging in safety-relevant performance while sleepy. Linear regression analyses were conducted to evaluate relationships between sleep duration, sleep quality, and work organization variables with safety composite variables.

RESULTS

Drivers reported long work hours, with over 70% of drivers working more than 11h daily. Drivers also reported a large number of miles driven per week, with an average of 2,812.61 miles per week, and frequent violations of hours-of-service rules, with 43.8% of drivers "sometimes to always" violating the "14-h rule." Sleep duration was longer, and sleep quality was better, on non-workdays compared on workdays. Drivers frequently operated motor vehicles while sleepy, and sleepiness impacted several aspects of safety-relevant performance. Sleep quality was better associated with driving while sleepy and with job performance and concentration than sleep duration. Sleep duration was better associated with accidents and accident risk than sleep quality.

DISCUSSION

Sleep quality appears to be better associated with safety-relevant performance among long-haul truck drivers than sleep duration. Comprehensive and multilevel efforts are needed to meaningfully address sleep quality among drivers.