Micro-epidemiology of the healthy worker effect?

Focusing on testosterone levels in male: A half-longitudinal study of polycyclic aromatic hydrocarbon exposure and diastolic blood pressure in coke oven workers

Polycyclic aromatic hydrocarbons (PAHs) can interfere with testosterone levels, and low levels of testosterone are associated with increased cardiovascular events. To explore the role of testosterone in PAHs exposure and cardiovascular health, we used data from the 2011-2016 National Health and Nutrition Examination Survey (NHANES) and a longitudinal database of 332 male coke oven workers from China. The urine PAHs, tobacco metabolites and plasma testosterone levels of coke oven workers were measured. There were inverse associations between serum (plasma) testosterone concentrations and the risk of dysarteriotony and dyslipidemia among the NHANES participants and coke oven workers. The results of the cross-lagged panel analysis among workers showed that the decrease in testosterone preceded the increase in diastolic blood pressure (DBP), and the absolute value of the path coefficient from baseline testosterone to follow-up DBP (β₂ = -8.162, P = 0.077) was significantly larger than the absolute value of the path coefficient from baseline DBP to follow-up testosterone (β₁ = -0.001, P = 0.781). Results from the half-longitudinal mediation analysis showed that baseline hydroxyfluorene predicted significant decreases in plasma testosterone from baseline to follow-up (path a: 0.71, 95% CI: 1.26, -0.16), whereas plasma testosterone at baseline also predicted significant increments in DBP from baseline to follow-up (path b: 9.22, 95% CI: 17.24, -1.19). The indirect effect of PAHs on DBP via plasma testosterone level was marginally significant (test for indirect effects a*b (P = 0.08)). In conclusion, testosterone level is a longitudinal precursor to increased DBP and plays an essential role in the association between PAHs exposure and damage to the cardiovascular system. Coke oven workers with low plasma testosterone levels are more likely to experience adverse changes in blood pressure and lipid levels after exposure to PAHs.

Application of the Ridden Horse Pain Ethogram to Horses Competing at the Hickstead-Rotterdam Grand Prix Challenge and the British Dressage Grand Prix National Championship 2020 and Comparison with World Cup Grand Prix Competitions

The Ridden Horse Pain Ethogram (RHpE) comprising 24 behaviours was developed to facilitate the identification of musculoskeletal discomfort, with scores of ≥8/24 indicating the presence of pain. The median RHpE score for 147 competitors at World Cup Grand Prix events from 2018 to 2020 was three (interquartile range [IQR] 1-4; range 0-7). The aim of the current study was to apply the RHpE to 38 competitors at the Hickstead-Rotterdam Grand Prix Challenge and 26 competitors at the British Dressage Grand Prix National Championship in 2020. The median RHpE scores were four (IQR 3-6; range 0-8) and six (IQR 4-7; range 1-9), respectively, which were both higher (p = 0.0011 and p = 0.0000) than the World Cup competitors' scores. Ears back ≥ 5 s (p = 0.005), intense stare ≥ 5 s (p = 0.000), repeated tail swishing (p = 0.000), hindlimb toe drag (p = 0.000), repeated tongue-out (p = 0.003) and crooked tail-carriage (p = 0.000) occurred more frequently. These were associated with a higher frequency of lameness, abnormalities of canter, and errors in rein-back, passage and piaffe, canter flying-changes and canter pirouettes compared with World Cup competitors. There was a moderate negative correlation between the dressage judges' scores and the RHpE scores (Spearman's rho -0.66, p = 0.0002) at the British Championship. Performance and welfare may be improved by recognition and appropriate treatment of underlying problems.

Respiratory Health Outcomes, Rhinitis, and Eczema in Workers from Grain Storage Facilities in Costa Rica

Objectives

To examine the associations of inhalable grain dust exposure with respiratory health outcomes, rhinitis, and eczema reported by workers from rice, wheat, and maize storage facilities.

Methods

A cross-sectional study of 136 workers (73 operators and 63 administrative staff and other workers) from eight Costa Rican grain storage facilities was conducted in 2014-2015. Full-shift personal inhalable dust samples from all workers were collected. Study participants were administered a short version of the European Community Respiratory Health Survey questionnaire to identify symptoms of asthma, chronic bronchitis, rhinitis, and eczema. Associations between grain dust exposure and health outcomes were assessed using multivariable logistic and negative binomial regression models adjusted for age, smoking history, grain type, and presence of pets or farm animals in the home.

Results

The median inhalable grain dust concentration was 2.0 (25th to 75th percentile: 0.3-7.0) mg m-3. Higher concentrations of inhalable dust were associated with increased odds of (i) asthma symptoms or medication use [adjusted Odds ratio (ORa) per 10-fold increase in dust concentration 2.7; 95% confidence interval (CI): 1.3-6.7]; (ii) a score of at least two out of five symptoms suggestive of asthma (ORa 1.2; 95% CI: 1.0-1.3); and (iii) eczema (ORa 3.6; 95% CI: 1.7-9.6). No associations of inhalable grain dust exposure with chronic bronchitis and rhinitis were observed.

Conclusions

High exposure to inhalable dust in Costa Rican grain storage facilities was associated to asthma symptoms and eczema in workers.

Relative longevity among retired military personnel: a historical-cohort study

BACKGROUND

Occupation is a significant factor affecting life, health and well-being. Long-term military service is a unique career path that may have an influence on life expectancy, even after excluding obvious risks such as battlefield mortality. However, it remains unclear what the effects of a military career are on the life trajectory of personnel after retiring from service. This study compared life expectancy among retired military personnel (RMP) to their sex and birth cohort-specific reference populations.

METHODS

For this historical cohort study, we collected data on the sex, year of birth, year of death, time in service, and rank at end of service for 4862 Israeli RMPs. Data on reference populations were provided by the Israel Central Bureau of Statistics by birth decade from 1900 to 1989. We calculated the difference between each individual RMP's age at death and the "expected" age at death, based on sex and birth cohort-specific means in the reference populations.

RESULTS

Overall, 67.9 % of RMPs lived longer than average relative to their sex-specific birth cohort. This difference in life expectancy was more pronounced among women than among men. There was a significant trend of increasing differences between RMP males and reference males over time (P < 0.002), whereas no significant trend was identified among females. Length of service and rank were not associated with relative longevity for RMPs.

CONCLUSIONS

The mechanism of the protective effect of military service on life expectancy remains unknown, but our findings indicate that it affects men and women differently, with women being more likely to benefit from the potential protective effect of military service. The healthy worker effect is known to vary from one occupation to another, and to the best of our knowledge, this is the first attempt to quantify the magnitude of the healthy worker effect among career military servicemen and women.

Limitations and plausibility of the Pliocene lignite hypothesis in explaining the etiology of Balkan endemic nephropathy

BACKGROUND

Balkan endemic nephropathy (BEN) is a chronic, tubulointerstitial renal disease often accompanied by urothelial cancer that has a lethality of nearly 100%.

INTRODUCTION

One of the many factors that have been proposed to play an etiological role in BEN is exposure to organic compounds from Pliocene lignite coal deposits via the drinking water in endemic areas.

OBJECTIVES

The objective of this study was to systematically evaluate the role of the tenets of the Pliocene lignite hypothesis in the etiology of BEN in order to provide an improved understanding of the hypothesis for colleagues and patients alike.

METHODS

A comprehensive compilation of the possible limitations of the hypothesis, with each limitation addressed in turn is presented.

RESULTS

The Pliocene lignite hypothesis can best account for, is consistent with, or has the potential to explain the evidence associated with the myriad of factors related to BEN.

CONCLUSIONS

Residents of endemic areas are exposed to complex mixtures containing hundreds of organic compounds at varying doses and their potentially more toxic (including nephrotoxic) and/or carcinogenic metabolites; however, a multifactorial etiology of BEN appears most likely.

An investigation of risk factors for foot-related lameness in a United Kingdom referral population of horses

Lameness relating to the foot of the horse is common, but the majority of information concerning risk factors for injury is anecdotal. The objectives of this study were to investigate risk factors for foot-related pain in a referral population of horses, with particular reference to injury/disease of the podotrochlear apparatus (PTA), by comparison with the remainder of the clinic population. It was hypothesised that there would be an increased risk of foot pain associated with breed, work discipline, age, height and bodyweight (BW). A retrospective study of all horses examined at a referral centre between 2001 and 2010 was performed using univariable and multivariable logistic regression analyses. There were 4618 horses investigated, 1132 of which had foot pain. There was increased risk of foot pain in multivariable analyses (all categories combined) in horses aged 6-9 and 10-15 years (OR = 1.60 and 1.72, respectively), compared with horses <6 years old, in show jumpers (OR = 1.44) compared with dressage horses, Thoroughbred cross-breeds (OR = 1.53) compared with Warmbloods and in horses with a BW:height ratio in the upper two quartiles (3.45-3.71 or >3.71; OR = 1.55 and 1.44, respectively), compared with the lowest quartile (<3.19). Racehorses had reduced risk for all types of foot pain combined (OR = 0.13) compared with dressage horses. Risk factors for PTA injury were age (10-15 years, OR = 2.12; >15 years, OR = 3.36, compared with <6 years old), BW:height ratio (>3.45-3.71 (OR = 2.75), >3.71 (OR = 2.06), compared with <3.19) and Thoroughbred cross-breed (OR = 1.73) compared with Warmbloods. Show jumpers had an increased risk of PTA and other injuries (OR = 2.29) when compared with dressage horses. Age, breed, work discipline and BW:height ratio influenced the risk of foot pain, but other factors probably also play a role.

A worksite vitality intervention to improve older workers' lifestyle and vitality-related outcomes: results of a randomised controlled trial

Objective

To evaluate the effectiveness of a worksite vitality intervention on vigorous physical activity (VPA), fruit intake, aerobic capacity, mental health and need for recovery after work among older hospital workers (ie, 45 years and older).

Methods

The 6-month intervention was evaluated using a randomised controlled trial design. Workers who were randomised to the intervention group (n=367; control: n=363) received the Vital@Work intervention containing (1) a Vitality Exercise Program (VEP) combined with (2) three visits to Personal Vitality Coach. The VEP consisted of a weekly yoga session, a weekly workout session and weekly unsupervised aerobic exercising. Free fruit was provided at the VEP. Data on the outcome measures were collected (ie, year 2009–2010) at baseline (n=730) and 6 months of follow-up after baseline (n=575) using questionnaires, accelerometers and 2 km walk tests. Effects were analysed according to the intention-to-treat principle with complete cases (n=575) and imputed data (n=730) using linear regression analyses. Additional analyses were performed for high yoga and workout compliance (ie, >mean number of sessions).

Results

Effects were found for sports activities (β=40.4 min/week, 95% CI 13.0 to 67.7) and fruit intake (β=2.7 pieces/week, 95% CI 0.07 to 4.7) and were stronger for workers with high compliance to yoga (sport: β=49.6 min/week, 95% CI 13.9 to 85.2; fruit: β=3.8 pieces/week, 95% CI 1.1 to 6.4) and workout sessions (sport: β=72.9 min/week, 95% CI 36.1 to 109.8; fruit: β=4.0 pieces/week, 95% CI 1.1 to 6.4). The intervention group lowered their need for recovery, when compared to controls (β=−3.5, 95% CI −6.4 to −0.54), with stronger effects for high workout compliance (β=−5.3, 95% CI −9.3 to −1.3). No effects were found on VPA, aerobic capacity or mental health.

Conclusions

Implementation of worksite yoga and workout facilities and minimal fruit interventions should be considered by employers to promote transitions into healthier lifestyles and thereby health.