Ergonomics 2
Wednesday 8 October 2025, 13.30 – 14.30 Glow
Chairs: Katarina Kjellberg, Henk van der Molen
Association between high occupational physical workload and ischemic heart disease, and influence of cardiorespiratory fitness
Karin Berglund (presenter)
Melody Almroth, Elin Ekblom-Bak, Daniel Falkstedt, Tomas Hemmingsson, Katarina Kjellberg
Abstract
High occupational physical workload may increase the risk of cardiovascular disease, while cardiorespiratory fitness could help prevent negative health effects. This study aimed to examine the association between high occupational physical workload in mid-life and later ischemic heart disease (IHD), and whether this relationship is influenced by cardiorespiratory fitness in youth. This study included 284,436 men born between 1951–1961. Occupational physical workload was assessed using a job exposure matrix in 2005 (age 44–54) and participants were followed for IHD incidence and mortality between 2006–2020 (age 45–69). Cardiorespiratory fitness in youth was assessed during military conscription using a maximal cycle test. Cox regression and additive interaction modelling, using the synergy index (SI), were applied. High occupational physical workload in mid-life was associated with increased risk of incident IHD (HR 1.34, 95% CI 1.29–1.39) and IHD mortality (HR 1.93, 95% CI 1.75–2.14), compared to low occupational physical workload. After adjusting for confounders including childhood socioeconomic position, cognitive ability, body mass index, blood pressure, and education, the associations were attenuated but remained significant: HR 1.06 (95% CI 1.02–1.11) for incident IHD and HR 1.38 (95% CI 1.23–1.55) for IHD mortality. The combination of low cardiorespiratory fitness in youth and later high occupational physical workload showed the highest IHD risk, indicating an additive interaction, though the SI was non-significant. High occupational physical workload in mid-life was associated with increased risks of IHD incidence and, more strongly, IHD mortality. The highest risk was observed in those with the combination of low fitness and high workload. These findings support workplace and public health strategies aimed at reducing physical workload and enhancing cardiorespiratory fitness, particularly for youths entering physically demanding occupations.
Changes in publicly insured general practitioner (GP) consultation durations and care plans before and after workplace injury among workers receiving workers’ compensation
Preeti Maharjan (presenter)
Michael Di Donato, Daniel Griffiths, Danielle Mazza, Alex Collie
Abstract
Objective General practitioner (GP) services in Australia are funded by the Medicare Benefits Scheme (universal public health insurance scheme). However, for work-related injuries, GP services are funded by an employer-funded workers’ compensation scheme. This study examined changes in publicly-funded GP service use before and after workplace injury in those with accepted workers’ compensation claims, focusing on four consultation duration types and use of GP-provided mental health and chronic disease management plans. Materials and Methods A retrospective controlled cohort data linkage study containing publicly-funded GP services for 3755 injured workers with long (104+ weeks) workers’ compensation scheme claims in New South Wales, Australia. We used interrupted time series analysis comparing the monthly rates (per 1000 workers) of six GP service types, for 12 months before to 24 months after injury. Acute and long-term step and trend changes were compared to those observed in a control group of 10,113 individuals from the community without workers’ compensation claims. Results Injured workers had 1600 more GP services per 1000 workers per year post-injury compared to community control. Post-injury, the monthly rate of consultations increased 45% (IRR: 1.45, 95% CI: 1.32, 1.59) for consultations lasting 6 to 20 minutes, with up to a 137% (IRR: 2.37, 95% CI: 1.35, 4.20) increase for consultations lasting 40 to 60 minutes. Monthly GP mental health care and chronic disease management plan rates increased by 84% (IRR: 1.84, 95% CI: 1.17, 2.93) and 20% (IRR: 1.20, 95% CI: 0.78, 1.86), respectively. Following an initial acute increase, the monthly post-injury rate decreased, with slopes varying between 3% to 9%. Conclusions All types of publicly funded GP consultations temporarily increased during initial months following injury, regardless of workers’ compensation status. Injured workers continued accessing healthcare above pre-injury levels, likely due to delayed claim acceptance or increased care needs.
Investigating differences in return-to-work for workers with work-related chronic pain and concurrent psychological injuries in British Columbia
Harman Sandhu (presenter)
Robert Macpherson, Lillian Tamburic, Mieke Koehoorn, Christopher McLeod
Abstract
Objectives To investigate differences in time for return-to-work (RTW) among psychological, chronic pain, and concurrent psychological with chronic pain injuries and to identify the most influential factors affecting the likelihood of RTW for each injury type. Methods Workers’ compensation claims data were used to identify workers (n=414,507) with an accepted time-loss claim due to work-related psychological, chronic pain, concurrent psychological with chronic pain injuries, or other injury types occurring between 2012 and 2019, with up to 3 years (1095 days) of follow-up. Descriptive statistics were used to analyze differences in time to RTW. Multivariate logistic regression was used to assess the role of socio-demographic and work characteristics in determining the likelihood of RTW for each injury type. Results Descriptive statistics reveal substantial differences in days to RTW after injury, with concurrent psychological with chronic pain having the longest durations (median=1095 days [IQR:1095 – 1095 days]), followed by chronic pain (median=1095 days [IQR:327 – 1095 days]) and psychological (median=422.5 days [IQR:74 – 1095 days]). All other injuries had a median of 21 days [IQR:7 – 83 days]. Variables such as older age and smaller firm size reduced the likelihood of RTW across all injury types, while other variables had injury-specific effects. For example, men were less likely to RTW compared to women (OR:0.86 [95% CI:0.77 – 0.96]) for psychological injury; workers with lower wages were less likely to RTW compared to those with higher wages (OR:0.58 [95% CI:0.52 – 0.64]) for chronic pain; and, health occupations were less likely to RTW for concurrent psychological injury with chronic pain (OR:0.49 [95% CI:0.25 – 0.94]). Conclusion There were large differences in RTW across injury types, and various characteristics impacted the likelihood of RTW differently across injury types. The small proportion of workers who had RTW after 3 years for concurrent psychological injury with chronic pain injuries warrants further research. Funding: WorkSafeBC Research Training Award
Job Exposure Matrix on the incidence of carpal tunnel release surgery in the CONSTANCES cohort
Alexis Descatha (presenter)
Bradley Evanoff, Marc Fadel, Ryan Colvin, Ann Marie Dale, Céline Ribet, Annette Leclerc
Abstract
Background Most studies of Carpal Tunnel Syndrome have examined only current workplace exposures as risk factors. We examined the effects of both recent and past work exposures on the incidence of surgery for carpal tunnel release (CTR). Material and Methods Participants in a large prospective study (CONSTANCES) were surveyed. The survey included self-reported history of current and past jobs, allowing estimation of past and current workplace physical exposures using an existing job exposure matrix (JEM). CTR cases were ascertained through matching the surveys to national health insurance data. Poisson regression analyses (controlling for age, Body Mass Index, and sex) computed the relative risks (RR) of future CTR associated with different work exposures. Eleven exposures including physical force, repetition, posture, and keyboard use were categorized into quartiles. Models included different time periods of exposure and/or different exposure lag times. Results 777 cases of CTR were observed among the 56,289 person cohort. RR of CTR per 5 years of exposure in the upper quartile included 1.19[1.13-1.25] for pressing with the base of the hand, 1.17[1.12-1.23] for use of vibrating tools, 1.17[1.12-1.22] for rotation of the forearm, and 0.88[0.84-0.91] for keyboard use. Higher effect sizes were seen among current workers than among those who had not worked in 5 or more years. Lagging exposures by 3 and 5 years reduced the strengths of association. Discussion Use of a JEM in a large general population cohort allowed us to study the effects of both recent and past work exposures on the incidence of carpal tunnel syndrome. While more recent exposures had stronger associations with CTR, some past exposures were also associated with future risk of CTR.