Obesity and its relationship with occupational injury in the canadian workforce

The effect of clinically elevated body mass index on physiological stress during manual lifting activities

Individuals with a body mass index (BMI) classified as obesity constitute 27.7% of U.S. workers. These individuals are more likely to experience work-related injuries. However, ergonomists still design work tasks based on the general population and normal body weight. This is particularly true for manual lifting tasks and the calculation of recommended weight limits (RWL) as per National Institute of Occupational Safety & Health (NIOSH) guidelines. This study investigates the effects of BMI on indicators of physiological stress. It was hypothesized that, for clinically elevated BMI individuals, repeated manual lifting at RWL would produce physiological stress above safety limits. A repetitive box lifting task was designed to measure metabolic parameters: volume of carbon dioxide (VCO2) and oxygen (VO2), respiratory exchange ratio (RER), heart rate (HR), and energy expenditure rate (EER). A two-way ANOVA compared metabolic variables with BMI classification and gender, and linear regressions investigated BMI correlations. Results showed that BMI classification represented a significant effect for four parameters: VCO2 (p < 0.001), VO2 (p < 0.001), HR (p = 0.012), and EER (p < 0.001). In contrast, gender only had a significant effect on VO2 (p = 0.014) and EER (p = 0.017). Furthermore, significant positive relationships were found between BMI and VCO2 (R2 = 59.65%, p < 0.001), VO2 (R2 = 45.01%, p < 0.001), HR (R2 = 21.86%, p = 0.009), and EER (R2 = 50.83%, p < 0.001). Importantly, 80% of obese subjects exceeded the EER safety limit of 4.7 kcal/min indicated by NIOSH. Indicators of physiological stress are increased in clinically elevated BMI groups and appear capable of putting these individuals at increased risk for workplace injury.

An Examination of Washington State Workers’ Compensation Claims for Home-Based Health Care Workers, 2006 to 2016: Part 1. Description of Claims and Claimants

Home-based health care can be physically and emotionally demanding, resulting in injury or illness. Washington State’s workers’ compensation compensable claims between 2006 and 2016 were analyzed to describe the characteristics of injured home-based health care (HBHC) providers and the burden created by these injuries. Comparisons were made with clinical health care (CHC) providers, as well as between all compensable claims and work-related musculoskeletal disorder (WMSD) claims. Over 90% of claimants for both HBHC and CHC were female. The mean age of all compensable HBHC claimants (45.7 years) was significantly older than for CHC, with the majority (54.5%) between the ages of 40 and 59. However, HBHC claimants with WMSDs were younger, overall. Across health care type and claim type, the majority of injured care providers were overweight or obese (BMI ≥ 25). The highest mean age occurred among claimants injured from falls, either on the same level or to a lower level (HBHC: 48.3-48.6 years, CHC: 46.1-48.1 years). This same group also had the highest BMIs. WMSDs accounted for 47.3% of HBHC compensable claims and 50.3% for CHC. Falls on the same level were the second most common injury event among HBHC claims. For both HBHC and CHC, back injuries were the most common body part for both claim types (all compensable claims: 28.8% HBHC and 23.9% CHC, WMSD claims: 60.8% HBHC and 47.5% CHC). Overexertion was the injury event most attributed to WMSDs (HBHC: 82.6%, CHC: 71.6), overexertion during lifting being the most prevalent overexertion type (HBHC: 27.8%, CHC: 19.6%).

Association of overtime work and obesity with needle stick and sharp injuries in medical practice

BACKGROUND

Needle stick and sharps injuries (NSIs) may cause infections among medical personnel. Obesity and overtime work among medical personnel increase the incidence of work injuries.

AIM

To investigate whether overtime work and obesity increase the risk of NSIs.

METHODS

This cross-sectional study used the data of 847 hospital personnel, including 104 doctors, 613 nurses, 67 medical laboratory scientists, 54 specialist technicians, and nine surgical assistants. Of them, 29 participants notified the hospital of having at least one NSI in 2017. The data collected included age, overtime work, body mass index, medical specialty such as doctor or nurse, and professional grade such as attending physician or resident. The χ 2 and Fisher's exact tests were used to compare categorical variables. Multiple logistic regression analysis and the Sobel test were used to assess the risk of NSIs.

RESULTS

Overtime work, body weight, and medical specialty were significantly associated with NSIs (P < 0.05). After adjustment for risk factors, heavy overtime work was an independent risk factor for NSIs, and healthy body weight and nursing specialty were independent protective factors against NSIs. After adjustment for risk factors, medical personnel with healthy body weight has half as many NSIs as those with unhealthy body weight; the proportion of NSIs in doctors with healthy body weight was 0.2 times that in doctors with unhealthy body weight; the proportion of injuries among residents was 17.3 times higher than that among attending physicians; the proportion of injuries among junior nurses was 3.9 times higher than that among experienced nurses; the proportion of injuries among nurses with heavy overtime work was 6.6 times higher than that among nurses with mild overtime work; and the proportion of injuries among residents was 19.5 times higher than that among junior nurses. Heavy overtime work mediated the association of medical specialty with NSIs.

CONCLUSION

In addition to promoting the use of safety needles and providing infection control education, managers should review overtime schedules, and medical personnel should be encouraged to maintain a healthy weight.

Obesity impairs performing and learning a timing perception task regardless of the body position

Obesity has been associated with poorer sensorimotor performance. However, it remains unclear whether these obesity-related impairments can be mitigated by practice. In the present study, we sought to investigate the effects of practice on performing and learning a temporal estimation task, in women with and without obesity. The experimental task consisted of synchronizing the arrival of two rectangles at a target point. Limited to the pressing of a switch, the task was intended to minimize possible muscular fatigue, self-generated perturbations to balance and the need to accelerate/decelerate body segments. Participants were allowed to choose the displacement velocity of the rectangle they controlled and were informed that they would not be offered any choice over it during a test to come. To control for the effect of different body positions on sensorimotor performance and learning, the 19 women with obesity (BMI = 40.0 + 7.33, age = 44.2 + 6.6) and 20 without obesity (BMI = 22.3 + 1.95, age = 43 + 6.9) were assigned into 4 groups, according to their BMI and body position assumed during practice (standing upright with feet together or sitting). As no significant differences concerning body position were found, the data were reanalysed disregarding this factor. Results revealed that while both groups reduced errors during the Acquisition, participants with obesity showed poorer performance (Acquisition) and sensorimotor learning (Transfer). Given the experimental task and adopted procedures, our results tend to support the hypothesis that hindered perception and/or integration of sensory information is associated with obesity.

Body mass index trajectories among the Canadian workforce and their association with work environment trajectories over 17 years

OBJECTIVE

To determine the number of latent body mass index (BMI) trajectories from 1994 to 2010 among working Canadians and their association with concurrent trajectories in work environment exposures.

METHODS

Data of employed individuals from the longitudinal Canadian National Population Health Survey were used. Group-based trajectory modelling was used to determine the number of latent BMI trajectories and concurrent psychosocial work environment trajectories. A multinomial logistic regression of BMI trajectory membership on trajectories in work environment dimensions (skill discretion, decision latitude, psychological demands, job insecurity, social support, physical exertion) was then explored.

RESULTS

Four latent BMI trajectories corresponding to normal, overweight, obese and very obese BMI values were found. Each trajectory saw an increase in BMI (~2-4 kg/m²) over the 17-year period. A higher decision authority trajectory was associated with lower odds of belonging to the overweight and obese trajectories when compared with the normal weight trajectory. A decreasing physical exertion trajectory was associated with higher odds of belonging to the very obese trajectory when compared with the normal weight trajectory.

CONCLUSIONS

Four BMI trajectories are present in the Canadian workforce; all trajectories saw increased body weight over time. Declining physical exertion and lower decision authority in the work environment over time is associated with increased likelihood of being in overweight and obese trajectories.

Health Indicators of a Cohort of Midwest Farmers: Health Outcomes of Participants in the Certified Safe Farm Program

Occupational illness, injury, and fatality rates for those working in production agriculture are higher than in any other industry. A potential risk factor contributing to occupational injuries across all industries is acute or chronic co-morbidity (e.g., obesity, high blood pressure, high cholesterol), and related health issues that increase the risk for an occupational injury or illness. These chronic health conditions have been associated not only with increased risk for injuries, but also higher health-care costs, and greater absenteeism. Certified Safe Farm (CSF) is a comprehensive intervention program aimed to reduce occupational health and safety hazards and to promote general health among farmers. Prior publications have described CSF program efforts to reduce hazardous exposures, disabling injuries, organic dust toxic syndrome, occupational health-care costs, and to increase positive occupational health behaviors. This paper reports on the general health indicators of a cohort of 438 Iowa farm owner/operators enrolled in the CSF program. Overall, this study found that the farming population in Iowa has higher body mass index (BMI), but lower total cholesterol, low-density lipoprotein (LDL), and lower prevalence of hypertension compared to the general population. There was evidence that the combination of high blood pressure, cholesterol, and BMI were related to increased injury rates. Poor self-reported health status was also related to increased injuries but was not related to clinical health indicators. The CSF intervention led to improvements on health outcomes, particularly among those in the 35 to 49 age group. Little research has focused on the individual's general health status as a predictor of risk of occupational injury. This study suggests the need for additional research and interventions integrating occupational safety and health prevention along with health promotion.

Occupational medicine clinical practice data reveal increased injury rates among Hispanic workers

Background

Minnesota has an ethnically diverse labor force, with the largest number of refugees per capita in the United States. In recent years, Minnesota has been and continues to be a major site for immigrant and refugee resettlement in the United States, with a large population of both immigrant and native born Hmong, Hispanic, and East Africans. This study seeks to evaluate the injury risk among the evolving minority workforce in the Minnesota Twin Cities region.

Methods

A retrospective cohort study identifying work‐related injuries following pre‐employment examinations was performed using electronic health records from a large multi‐clinic occupational medicine practice. Preplacement examinations and subsequent work‐related injuries were pulled from the electronic health record using representative ICD‐10 codes for surveillance examinations and injuries. This study included patient records collected over a 2‐year period from January 1, 2015, through December, 2016. The patients in this cohort worked in a wide‐array of occupations including production, assembly, construction, law enforcement, among others.

Results

Hispanic minority workers were twice as likely to be injured at work compared with White workers. Hispanics were 2.89 times more likely to develop back injuries compared with non‐Hispanic workers, and 1.86 times more likely to develop upper extremity injuries involving the hand, wrist, or elbow.

Conclusion

Clinical practice data shows that Hispanic workers are at increased risk for work‐related injuries in Minnesota. They were especially susceptible to back and upper extremity injuries. Lower injury rates in non‐Hispanic minority workers, may be the result of injury underreporting and require further investigation.

The Relationship Between BMI and Work-Related Musculoskeletal (MSK) Injury Rates is Modified by Job-Associated Level of MSK Injury Risk

OBJECTIVE

The aim of this study was to examine the relationship between body mass index (BMI) and occupational musculoskeletal (MSK) injury rates, and the statistical interaction between BMI and occupational exposure to MSK hazards (measured by level of MSK injury risk based on job category).

METHODS

Using 17 years of data from 38,214 university and health system employees, multivariate Poisson regression modeled the interaction between BMI and MSK injury risk on injury rates.

RESULTS

A significant interaction between BMI and MSK injury risk was observed. Although the effect of BMI was strongest for 'low' MSK injury risk occupations, absolute MSK injury rates for 'mid'/'high' MSK injury risk occupations remained larger.

CONCLUSIONS

To address the occupational MSK injury burden, initiatives focused on optimal measures of workers' BMI are important but should not be prioritized over (or used in lieu of) interventions targeting job-specific MSK injury hazards.

Factors Influencing the Incidence of Obesity in Australia: A Generalized Ordered Probit Model

The increasing health costs of and the risks factors associated with obesity are well documented. From this perspective, it is important that the propensity of individuals towards obesity is analyzed. This paper uses longitudinal data from the Household Income and Labour Dynamics in Australia (HILDA) Survey for 2005 to 2010 to model those variables which condition the probability of being obese. The model estimated is a random effects generalized ordered probit, which exploits two sources of heterogeneity; the individual heterogeneity of panel data models and heterogeneity across body mass index (BMI) categories. The latter is associated with non-parallel thresholds in the generalized ordered model, where the thresholds are functions of the conditioning variables, which comprise economic, social, and demographic and lifestyle variables. To control for potential predisposition to obesity, personality traits augment the empirical model. The results support the view that the probability of obesity is significantly determined by the conditioning variables. Particularly, personality is found to be important and these outcomes reinforce other work examining personality and obesity.

Association between job stress and occupational injuries among Korean firefighters: a nationwide cross-sectional study

OBJECTIVE

We aimed to assess the nature of association between job stress and occupational injuries among firefighters in Korea.

DESIGN

Cross-sectional study.

SETTING

We conducted a nationwide survey using self-reported questionnaires in South Korea.

PARTICIPANTS

A survey was conducted among 30 630 firefighters; 25 616 (83.6%) responded. Our study included firefighters who were 20-59 years old. Individuals with <12 months of current job experience and those with missing data were excluded; ultimately, 14 991 firefighters were analysed.

RESULTS

Among fire suppression personnel, high job demands (OR=1.49, 95% CI 1.25 to 1.77), high interpersonal conflicts (OR=1.18, 95% CI 1.02 to 1.37), a poor organisational system (OR=1.33, 95% CI 1.14 to 1.55), and a negative workplace environment (OR=1.41, 95% CI 1.21 to 1.64) were associated with the occurrence of occupational injury; high job demands (OR=1.22, 95% CI 1.01 to 1.47) were also associated with the frequency of injuries. Among emergency medical services personnel, high job demands (OR=1.26, 95% CI 1.03 to 1.54), high interpersonal conflicts (OR=1.40, 95% CI 1.19 to 1.66), a poor organisational system (OR=1.55, 95% CI 1.30 to 1.85), lack of reward (OR=1.43, 95% CI 1.21 to 1.69) and a negative workplace environment (OR=1.30, 95% CI 1.10 to 1.54) were associated with the occurrence of occupational injury; low job control (OR=1.20, 95% CI 1.04 to 1.38), high interpersonal conflicts (OR=1.18, 95% CI 1.03 to 1.36), lack of reward (OR=1.17, 95% CI 1.02 to 1.35) and a negative workplace climate (OR=1.16, 95% CI 1.01 to 1.34) were also associated with a greater number of injuries. Among officers, high job demands (OR=1.96, 95% CI 1.35 to 2.85) and a negative workplace environment (OR=1.54, 95% CI 1.13 to 2.10) were associated with the occurrence of occupational injuries; however, there was no significant correlation between job stress and the number of injuries.

CONCLUSIONS

High job stress among firefighters was associated with both the occurrence of occupational injury, and also with an increased frequency of injuries. Therefore, job stress should be addressed to prevent occupational injuries among firefighters.

Prevalence of work-site injuries and relationship between obesity and injury among U.S. workers: NHIS 2004-2012

INTRODUCTION

Studies have reported associations between obesity and injury in a single occupation or industry. Our study estimated the prevalence of work-site injuries and investigated the association between obesity and work-site injury in a nationally representative sample of U.S. workers.

METHODS

Self-reported weight, height, and injuries within the previous three months were collected annually for U.S. workers in the National Health Interview Survey (NHIS) from 2004-2012. Participants were categorized as normal weight (BMI: 18.5-24.9kg/m(2)), overweight (BMI: 25.0-29.9), obese I (BMI: 30.0-34.9), and obese II (BMI: 35+). The prevalence of injury and prevalence ratios from fitted logistic regression models was used to assess relationships between obesity and injury after adjusting for covariates. Sampling weights were incorporated using SUDAAN software.

RESULTS

During the 9-year study period from 2004 to 2012, 1120 workers (78 workers per 10,000) experienced a work-related injury during the previous three months. The anatomical sites with the highest prevalence of injury were the back (14.3/10,000±1.2), fingers (11.5±1.3), and knees (7.1±0.8). The most common types of injuries were sprains/strains/twists (41.5% of all injuries), cuts (20.0%), and fractures (11.8%). Compared to normal weight workers, overweight and obese workers were more likely to experience work-site injuries [overweight: PR=1.25 (95% CI=1.04-1.52); obese I: 1.41 (1.14-1.74); obese II: 1.68 (1.32-2.14)]. These injuries were more likely to affect the lower extremities [overweight: PR=1.48, (95% CI=1.03-2.13); obese I: 1.70 (1.13-2.55); obese II: 2.91 (1.91-4.41)] and were more likely to be due to sprains/strains/twists [overweight: PR=1.73 (95% CI=1.29-2.31); obese I: PR=2.24 (1.64-3.06); obese II: PR=2.95 (2.04-4.26)].

CONCLUSIONS

Among NHIS participants, overweight and obese workers were 25% to 68% more likely to experience injuries than normal weight workers.

PRACTICAL APPLICATIONS

Weight reduction policies and management programs may be effectively targeted towards overweight and obese groups to prevent or reduce work-site injuries.

Identifying and mitigating risks for agricultural injury associated with obesity

In some occupational contexts overweight and obesity have been identified as risk factors for injury. The purpose of this study was to examine this hypothesis within farm work environments and then to identify specific opportunities for environmental modification as a preventive strategy. Data on farm-related injuries, height and weight used to calculate body mass index (BMI), and demographic characteristics were from the Phase 2 baseline survey of the Saskatchewan Farm Injury Cohort; a large cross-sectional mail-based survey conducted in Saskatchewan, Canada from January through May 2013. Multivariable logistic regression was used to examine associations between BMI and injury. Injury narratives were explored qualitatively. Findings were inconsistent and differed according to gender. Among women (n = 927), having overweight (adjusted OR: 2.94; 95% CI: 1.29 to 6.70) but not obesity (1.10; 95% CI: 0.35 to 3.43) was associated with an increased odds of incurring a farm-related injury. No strong or statistically significant effects were observed for men (n = 1406) with overweight or obesity. While injury-related challenges associated with obesity have been addressed in other occupational settings via modification of the worksite, such strategies are challenging to implement in farm settings because of the diversity of work tasks and associated hazards. We conclude that the acute effects of overweight in terms of injury do require consideration in agricultural populations, but these should also be viewed with a differentiation based on gender.

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Obesity can increase risk for injury through biological and physical mechanisms.

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Associations between BMI status and agricultural injury were examined.

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Findings were inconsistent and differed according to gender.

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Overweight is a potential risk factor for injury, specifically in farm women.

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We suggest ergonomic modifications that are potentially effective for farm settings.

Identification of Healthy Eating and Active Lifestyle Issues through Photo Elicitation

PURPOSE

Effective workplace wellness programs, featuring supports for healthy eating and active lifestyle behaviours, have been found to reduce health risks and the associated economic burdens for individuals, organizations, and their communities. As part of a larger study, the purpose of this research was to engage volunteer participants from a university community to identify healthy eating and active lifestyle barriers and supports.

METHODS

An ethics-approved, action-research design with photo elicitation technique was used to engage employees and students. Data were analyzed using qualitative analysis software.

RESULTS

Participants identified barriers and both current and future supports for healthy eating and active lifestyle on campus. These were coded under the sub-themes of food environment, food and nutrition quality, physical environment, physical activity, fitness centre, and awareness/communication.

CONCLUSION

Photo elicitation was determined to be an effective technique to engage participants. Despite many supports, members of the university community still found it difficult to follow healthy eating and active lifestyle behaviours; however, a number of practical future supports were identified. This study also provided valuable insight into the role that dietitians can play in the development of successful wellness programs.

Prevalence of Injury in Occupation and Industry: Role of Obesity in the National Health Interview Survey 2004 to 2013

OBJECTIVES

The aim of this study was to estimate prevalence of injury by occupation and industry and obesity's role.

METHODS

Self-reported injuries were collected annually for US workers during 2004 to 2013. Prevalence ratios (PRs) and 95% confidence intervals (CIs) were obtained from fitted logistic regression models.

RESULTS

Overall weighted injury prevalence during the previous three months was 77 per 10,000 workers. Age-adjusted injury prevalence was greatest for Construction and Extraction workers (169.7/10,000) followed by Production (160.6) among occupations, while workers in the Construction industry sector (147.9) had the highest injury prevalence followed by the Agriculture/Forestry/Fishing/Mining/Utilities sector (122.1). Overweight and obese workers were 26% to 45% more likely to experience injuries than normal-weight workers.

CONCLUSION

The prevalence of injury, highest for Construction workers, gradually increased as body mass index levels increased in most occupational and industry groups.

Two industrial cohorts: baseline characteristics and factors associated with obesity

OBJECTIVE

To describe demographic and health characteristics, and factors associated with obesity among production workers.

METHODS

This cross-sectional study analyzed baseline data from two occupational cohorts. Regression modeling was used to assess associations between worker characteristics and obesity.

RESULTS

A total of 1974 subjects were included in these analyses. The mean body mass index was 29.5 kg/m (SD = 6.5). Having smoked in the past and currently smoking decreased the odds of being obese in the WISTAH Distal Upper Extremity cohort, whereas those feeling depressed had increased odds of being obese. Being a Pacific Islander/Native Hawaiian and married increased the odds of obesity in the BackWorks Low Back Pain cohort.

CONCLUSIONS

Factors associated with obesity differed substantially between the two cohorts. Recognizing factors associated with obesity in specific work settings may provide opportunities for optimizing preventive workplace interventions.

Predictors Associated With Changes of Weight and Total Cholesterol Among Two Occupational Cohorts Over 10 Years

OBJECTIVE

To ascertain worker health characteristics and psychosocial factors associated with changes in body weight and total cholesterol (TC) among two production operation populations.

METHODS

We performed descriptive and predictive analysis of questionnaire data and biomedical measurements from two prospective cohort studies. Our key outcomes were changes in weight, and TC over 5 to 10 years between baseline and exit assessments.

RESULTS

A total of 146 subjects were analyzed. Increases in weight were associated with belief in being overweight and baseline overweight and obesity. Increases in TC levels were associated with female sex, belief that TC levels were "not good," and feeling depressed.

CONCLUSIONS

Most of the reported associations with increases in weight and TC levels are amenable to interventions and may be a target for workplace intervention programs.

The usefulness of "corrected" body mass index vs. self-reported body mass index: comparing the population distributions, sensitivity, specificity, and predictive utility of three correction equations using Canadian population-based data

Background

National data on body mass index (BMI), computed from self-reported height and weight, is readily available for many populations including the Canadian population. Because self-reported weight is found to be systematically under-reported, it has been proposed that the bias in self-reported BMI can be corrected using equations derived from data sets which include both self-reported and measured height and weight. Such correction equations have been developed and adopted. We aim to evaluate the usefulness (i.e., distributional similarity; sensitivity and specificity; and predictive utility vis-à-vis disease outcomes) of existing and new correction equations in population-based research.

Methods

The Canadian Community Health Surveys from 2005 and 2008 include both measured and self-reported values of height and weight, which allows for construction and evaluation of correction equations. We focused on adults age 18–65, and compared three correction equations (two correcting weight only, and one correcting BMI) against self-reported and measured BMI. We first compared population distributions of BMI. Second, we compared the sensitivity and specificity of self-reported BMI and corrected BMI against measured BMI. Third, we compared the self-reported and corrected BMI in terms of association with health outcomes using logistic regression.

Results

All corrections outperformed self-report when estimating the full BMI distribution; the weight-only correction outperformed the BMI-only correction for females in the 23–28 kg/m² BMI range. In terms of sensitivity/specificity, when estimating obesity prevalence, corrected values of BMI (from any equation) were superior to self-report. In terms of modelling BMI-disease outcome associations, findings were mixed, with no correction proving consistently superior to self-report.

Conclusions

If researchers are interested in modelling the full population distribution of BMI, or estimating the prevalence of obesity in a population, then a correction of any kind included in this study is recommended. If the researcher is interested in using BMI as a predictor variable for modelling disease, then both self-reported and corrected BMI result in biased estimates of association.

The effects of exercise training in addition to energy restriction on functional capacities and body composition in obese adults during weight loss: a systematic review

BACKGROUND

Obesity is associated with impairments of physical function, cardiovascular fitness, muscle strength and the capacity to perform activities of daily living. This review examines the specific effects of exercise training in relation to body composition and physical function demonstrated by changes in cardiovascular fitness, and muscle strength when obese adults undergo energy restriction.

METHODS

Electronic databases were searched for randomised controlled trials comparing energy restriction plus exercise training to energy restriction alone. Studies published to May 2013 were included if they used multi-component methods for analysing body composition and assessed measures of fitness in obese adults.

RESULTS

Fourteen RCTs met the inclusion criteria. Heterogeneity of study characteristics prevented meta-analysis. Energy restriction plus exercise training was more effective than energy restriction alone for improving cardiovascular fitness, muscle strength, and increasing fat mass loss and preserving lean body mass, depending on the type of exercise training.

CONCLUSION

Adding exercise training to energy restriction for obese middle-aged and older individuals results in favourable changes to fitness and body composition. Whilst weight loss should be encouraged for obese individuals, exercise training should be included in lifestyle interventions as it offers additional benefits.

Obesity and occupational injury: a prospective cohort study of 69,515 public sector employees

Background

Obesity and overweight are suggested to increase the risk of occupational injury but longitudinal evidence to confirm this is rare. We sought to evaluate obesity and overweight as risk factors for occupational injuries.

Methodology/Principal Findings

A total of 69,515 public sector employees (80% women) responded to a survey in 2000–2002, 2004 or 2008. Body mass index (kg/m²) was derived from self-reported height and weight and was linked to records of subsequent occupational injuries obtained from national registers. Different injury types, locations and events or exposures (the manner in which the injury was produced or inflicted) were analyzed by body mass index category adjusting for baseline socio-demographic characteristics, work characteristics, health-risk behaviors, physical and mental health, insomnia symptoms, and sleep duration. During the mean follow-up of 7.8 years (SD = 3.2), 18% of the employees (N = 12,204) recorded at least one occupational injury. Obesity was associated with a higher overall risk of occupational injury; multivariable adjusted hazard ratio (HR) 1.21 (95% CI 1.14–1.27). A relationship was observed for bone fractures (HR = 1.37; 95% CI: 1.10–1.70), dislocations, sprains and strains (HR = 1.36; 95% CI: 1.25–1.49), concussions and internal injuries (HR = 1.26; 95% CI: 1.11–1.44), injuries to lower extremities (HR = 1.62; 95%: 1.46–1.79) and injuries to whole body or multiple sites (HR = 1.37; 95%: 1.10–1.70). Furthermore, obesity was associated with a higher risk of injuries caused by slipping, tripping, stumbling and falling (HR = 1.55; 95% CI: 1.40–1.73), sudden body movement with or without physical stress (HR = 1.24; 95% CI: 1.10–1.41) and shock, fright, violence, aggression, threat or unexpected presence (HR = 1.33; 95% CI: 1.03–1.72). The magnitude of the associations between overweight and injuries was smaller, but the associations were generally in the same direction as those of obesity.

Conclusions/Significance

Obese employees record more occupational injuries than those with recommended healthy weight.

Have guidelines addressing physical activity been established in nonalcoholic fatty liver disease?

The purpose of this review was to highlight, in relation to the currently accepted pathophysiology of non-alcoholic fatty liver disease (NAFLD), the known exercise habits of patients with NAFLD and to detail the benefits of lifestyle modification with exercise (and/or physical activity) on parameters of metabolic syndrome. More rigorous, controlled studies of longer duration and defined histopathological end-points comparing exercise alone and other treatment are needed before better, evidence-based physical activity modification guidelines can be established, since several questions remain unanswered.

Independent effects of sleep duration and body mass index on the risk of a work-related injury: evidence from the US National Health Interview Survey (2004-2010)

Fatigue has been linked to adverse safety outcomes, and poor quality or decreased sleep has been associated with obesity (higher body mass index, BMI). Additionally, higher BMI is related to an increased risk for injury; however, it is unclear whether BMI modifies the effect of short sleep or has an independent effect on work-related injury risk. To answer this question, the authors examined the risk of a work-related injury as a function of total daily sleep time and BMI using the US National Health Interview Survey (NHIS). The NHIS is an in-person household survey using a multistage, stratified, clustered sample design representing the US civilian population. Data were pooled for the 7-yr survey period from 2004 to 2010 for 101 891 "employed" adult subjects (51.7%; 41.1 ± yrs of age [mean ± SEM]) with data on both sleep and BMI. Weighted annualized work-related injury rates were estimated across a priori defined categories of BMI: healthy weight (BMI: <25), overweight (BMI: 25-29.99), and obese (BMI: ≥30) and also categories of usual daily sleep duration: <6, 6-6.99, 7-7.99, 8-8.99, and ≥9 h. To account for the complex sampling design, including stratification, clustering, and unequal weighting, weighted multiple logistic regression was used to estimate the risk of a work-related injury. The initial model examined the interaction among daily sleep duration and BMI, controlling for weekly working hours, age, sex, race/ethnicity, education, type of pay, industry, and occupation. No significant interaction was found between usual daily sleep duration and BMI (p = .72); thus, the interaction term of the final logistic model included these two variables as independent predictors of injury, along with the aforementioned covariates. Statistically significant covariates (p ≤ .05) included age, sex, weekly work hours, occupation, and if the worker was paid hourly. The lowest categories of usual sleep duration (<6 and 6-6.9 h) showed significantly (p ≤ .05) elevated injury risks than the referent category (7-8 h sleep), whereas sleeping >7-8 h did not significantly elevate risk. The adjusted injury risk odds ratio (OR) for a worker with a usual daily sleep of <6 h was 1.86 (95% confidence interval [CI]: 1.37-2.52), and for 6-6.9 h it was 1.46 (95% CI: 1.18-1.80). With regards to BMI, the adjusted injury risk OR comparing workers who were obese (BMI: ≥30) to healthy weight workers (BMI: <25) was 1.34 (95% CI: 1.09-1.66), whereas the risk in comparing overweight workers (BMI: 25-29.99) to healthy weight risk was elevated, but not statistically significant (OR = 1.08; 95% CI: .88-1.33). These results from a large representative sample of US workers suggest increase in work-related injury risk for reduced sleep regardless of worker's body mass. However, being an overweight worker also increases work-injury risk regardless of usual daily sleep duration. The independent additive risk of these factors on work-related injury suggests a substantial, but at least partially preventable, risk.