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Prostate cancer (PCa) incidence has steadily increased in Sweden, more steeply in the mid-1990s caused by increased opportunistic prostate-specific antigen (PSA) testing. Tallness, normal weight, and non-smoking are associated with more PSA testing, which increases detection of low-risk and localised PCa. We investigated time trends of height, body mass index (BMI), and smoking with PCa risk in 171,889 men in Sweden aged 50–64 years at baseline, who were linked to nationwide cancer registers during follow-up. Cox regression determined the association of these factors assessed before 1980, 1980–1994, and 1995–2004 with PCa risk. During 15 follow-up years, 8,049 men were diagnosed with PCa. The association of height with PCa was weakly positive across all calendar periods. For obesity (BMI ≥30 kg/m2) vs. normal weight (BMI 18.5–24.9 kg/m2) and current vs. never smoking, the associations changed from null before 1980 (HR 1.03, 95% CI 0.86–1.23, and 1.11, 95% CI 0.97–1.27) to negative in 1995–2004 (HR 0.83, 95% CI 0.74–0.93, and 0.86, 95% CI 0.79–0.93; pinteraction between periods = 0.05 and 0.001). In men with clinical characteristics available, height was positively associated with both aggressive and non-aggressive PCa whilst obesity and smoking showed negative associations only with non-aggressive PCa. These findings likely reflect differences in PSA testing by BMI and smoking habits and contribute important knowledge for etiological studies of PCa.

The main aim of this study was to describe the degree of cold exposure and occupational physical activity within three different outdoor occupational groups in northern Sweden using both technical measurements and self-reported survey items. The cold exposure and physical activity of workers in preschool, park and maintenance and power grid sectors (N = 133) were examined using a digital survey, temperature loggers and thigh-worn accelerometers. In the survey, 33% of workers indicated that they often or always felt cold at work, and 39% reported that they had inadequate knowledge about cold weather protection. The median (interquartile range, IQR) duration of working at ambient temperatures below 10°C was 131 (157) minutes. The physical activity while working outdoors was composed of sitting (20%), standing (54%) and walking (26%). About one-third of the participants reported that they often or always felt cold at their workplace, with an average of more than two hours spent outside at temperatures below 10°C. Possible remedies include increasing physical activity and improving thermal insulation of the clothing.

Objective: Workers exposed to hand-arm vibration (HAV) commonly experience discomfort in their hands when cold. There is a lack of diagnostic tests for such abnormal cold sensitivity. The main aim of our study was to evaluate the results of cold stress testing in relation to self-reported cold sensitivity among HAV-exposed workers.

Methods: We recruited 225 workers exposed to HAV who responded to a written screening question about cold sensitivity. Cold stress testing was conducted, where the right hand was immersed in 3.0 °C circulating water for up to 60 seconds. The tolerance time for immersion as well as continuous pain ratings on a digital visual analog scale (ranging from 0 to 100 millimeters) were recorded.

Results: The study sample consisted of 208 males (92.4 %) and 17 females, with a mean (SD) age of 40.6 (13.7) years. Among the 190 workers that completed cold stress testing, the mean (SD) tolerance time was 43.7 (16.4) seconds, mean (SD) maximum pain rating 69.8 (27.6) millimeters, and mean (SD) time to maximum pain 38.7 (15.9) seconds. Cold sensitivity was reported by 54 workers (24.1 %). Cold sensitivity was not statistically significantly associated with tolerance time or maximum pain rating, but symptomatic workers had a shorter time to maximum pain (p = 0.018).

Conclusions: Workers who reported cold sensitivity experienced a more rapid increase in cold-related pain, had a tendency towards shorter tolerance time but did not differ in maximum pain ratings. Further studies are needed to determine how to effectively investigate cold sensitivity among HAV-exposed workers.

Objectives: To prospectively determine the association between occupational biomechanical exposures and the incidence of surgically treated carpal tunnel syndrome (CTS) in Swedish male construction workers.

Methods: A cohort of 203 866 Swedish male construction workers who participated in a national occupational health surveillance programme between 1971 and 1993 were followed for CTS surgery between 2001 and 2019. Age, height, weight, smoking status and construction trade were obtained from programme records. CTS surgery cases were defined using the diagnostic code for CTS and surgical procedure code for peripheral median nerve decompression in the Swedish National Patient Register. Biomechanical exposure estimates were assigned by trade from a job-exposure matrix. The relative risk (RR) of CTS surgery for each biomechanical exposure was assessed with multivariable negative binomial regression modelling.

Results: The study included 3851 cases and the total incidence rate of CTS surgery was 137.6 cases per 100 000 person-years. Associations were found for upper extremity load (RR 2.6; 95% CI 2.2 to 3.0), repetitive wrist flexion and extension (RR 2.6; 95% CI 2.2 to 3.0), full wrist extension (RR 2.3; 95% CI 1.9 to 2.6), power grip (RR 2.5; 95% CI 2.2 to 2.9), pinch grip (RR 2.0; 95% CI 1.7 to 2.4), handheld tool use (RR 2.3; 95% CI 2.0 to 2.7) and hand-arm vibration exposure (RR 2.3; 95% CI 1.9 to 2.7).

Conclusions: Occupational upper extremity load and postural exposures were associated with increased risk for surgical treatment for CTS in this large construction worker cohort. Preventive actions and consideration of occupation on assessment are warranted.

OBJECTIVES: This study aimed to assess the associations between occupational biomechanical factors and occurrence of surgically treated lumbar disc herniation (LDH) and describe the consequences in terms of early exit from the labor market.

METHODS: A cohort of 262 850 male construction workers participating in a national occupational health surveillance program was followed prospectively for 33 years (1987-2019). Occupational biomechanical exposures were assessed by a job exposure matrix (JEM) based on specific occupational groups. Workers who underwent surgical treatment for LDH were identified from the national patient register and data on disability pension from the Swedish Social Insurance Agency. Poisson regression models were used to estimate relative risks (RR) and 95% confidence intervals (CI) for biomechanical exposures, adjusted for age, body mass index, smoking status, height and time period.

RESULTS: There were 2451 cases of surgical treatment for LDH and the incidence peaked at age 40-45 years. Increased risks were found for often lifting >25 kg (RR 1.77, 95% CI 1.06-2.94), extreme lumbar flexion/extension (RR 1.60, 95% CI 1.37-1.88) and high exposure to whole-body vibration (RR 1.32, 95% CI 1.05-1.65). Among cases, the mean age for exiting the labor market due to disability pension was 55.9 years for white-collar workers and 51.7 years for construction workers.

CONCLUSIONS: Occupational exposure to heavy lifting and working in non-neutral back postures was associated with increased risk of surgical treatment for LDH. Construction workers who have had surgery for LDH exited the labor market with disability pension earlier than white-collar workers.

OBJECTIVES: The study investigated the association between occupational biomechanical risk factors and the occurrence of thumb carpometacarpal joint osteoarthritis (CMC1 OA) in construction workers.

METHODS: Male construction workers (n=237 525), participating in a Swedish occupational surveillance programme between 1971 and 1993, were followed between 1997 and 2019. CMC1 OA diagnoses were identified through linkage with national medical registries. Job title, smoking status, height, weight and age were collected from the surveillance programme. A job exposure matrix (JEM) was developed with exposure estimates on biomechanical risk factors for each occupational group. Relative risk (RR) of CMC1 OA diagnosis was calculated using a Poisson regression model.

RESULTS: There was an increased risk of CMC1 OA for all biomechanical risk factors (RR range 1.3-1.5). Exposure-response patterns were seen for repetitive wrist flexion and extension (low: RR 1.30 (95% CI 1.07 to 1.59), moderate: 1.32 (95% CI 1.07 to 1.62), high: 1.45 (95% CI 1.19 to 1.75)), wrist extension (low: 1.31 (95% CI 1.09 to 1.59), moderate: 1.41 (95% CI 1.17 to 1.70) and heavy lifting (low: 1.13 (95% CI 0.92 to 1.38), moderate: 1.45 (95% CI 1.18 to 1.77), high: 1.50 (95% CI 1.24 to 1.82). Electricians (1.29 (95% CI 1.03 to 1.89)), concrete workers (1.31 (95% CI 1.02 to 1.67)), plumbers (1.37 (95% CI 1.07 to 1.76)), sheet-metal workers (1.58 (95% CI 1.18 to 2.10)), wood workers (1.66 (95% CI 1.36 to 2.03)), repairers (1.75 (95% CI 1.06 to 2.90)) and glass workers (2.21 (95% CI 1.42 to 3.44) had an increased risk of CMC1 OA compared with the reference group.

CONCLUSION: Wrist movements and hand loading were associated with CMC1 OA.

Millions of people are exposed to cold environments daily. Adverse health risks are prominent for outdoor and cold storage workers. Therefore, a systematic risk management approach is highly motivated. This scoping review aimed to describe the current knowledge regarding risk management of cold exposure hazards in the occupational setting. We also examined differences between sexes in risk management practices regarding cold exposure.

The review included 25 peer-reviewed papers from 1980 to current in English and the Nordic languages, which could be divided into two categories: risk assessment and risk treatment. The risk assessment category included 17 papers, which investigated specific topics such as personal protective equipment, models for thermal balance, and individual differences regarding sex and body mass index. The risk treatment category included eight peer-reviewed papers, which emphasised the use of different protective or preventive measures and highlighted the importance of successful implementation and improvement of good practices.

To conclude, the previous literature on risk management of cold work was mainly oriented around technical risk assessment. However, there seems to be a lack of knowledge regarding implementation, resulting in inadequate protection for workers. Moreover, research was scarce regarding sex-dependent differences in risk management among workers exposed to cold.

Healthcare employees are experiencing poor wellbeing at an increasing rate. The healthcare workforce is exposed to challenging tasks and a high work pace, a situation that worsened during and after the COVID-19 pandemic. In turn, exposure to these high demands contributes to poor health, increased turnover, reduced job satisfaction, reduced efficacy, and reduced patient satisfaction and safety. Therefore, it is imperative that we identify measures to mitigate this crisis. One piece of this puzzle is how to implement sustainable tools and processes to improve the work environment of healthcare organizations. In this paper, we present the study protocol for the outlining and piloting of a joint training for pairs of healthcare line managers and their associated health and safety representatives in a Swedish healthcare organization. The objective of the training is to aid and advance the implementation of interventions to improve the work environment at the unit level. Following recommendations in the literature, the training is based on a stepwise approach that considers the specific context and focuses on the involvement of employees in creating interventions based on their needs. A central component of the training is the development of the pairs’ collaboration in prioritizing, developing, implementing, and evaluating the interventions. The training is based on an on-the-job train-the-trainer approach in which participants are progressively trained during four workshops in the steps of a participatory intervention process. Between these workshops, the pairs follow the same progressive steps together with their employees to develop and implement interventions at their unit. The pilot will involve four pairs (i.e., eight participants) representing different parts and functions of the organization and will be conducted over a period of three months. We will use a mixed method design to evaluate preconditions, the process, and proximal transfer and implementation outcome factors of the training. The overall aim of the pilot is to appraise its feasibility and be able to adjust the training before a potential scale-up.

Background: Obesity, assessed by body mass index (BMI), is an established risk factor for 13 cancers. We aimed to identify further potential obesity-related cancers and to quantify their association with BMI relative to that of established obesity-related cancers.

Methods: Using Cox regression models on 4,142,349 individuals in Sweden (mean age 27.1 years at weight measurement), we calculated hazard ratios (HRs) for the association between BMI and the risk of 122 cancers and cancer subtypes, grouped by topography and morphology. Cancers with a positive association (i.e., HR >1) at an α-level of 0.05 for obesity (BMI ≥30 kg/m²) vs. normal weight (BMI 18.5–24.9 kg/m²) or per 5 kg/m² higher BMI, for which obesity is not an established risk factor, were considered potentially obesity related.

Findings: After 100.2 million person-years of follow-up, 332,501 incident cancer cases were recorded. We identified 15 cancers in men and 16 in women as potentially obesity related. These were cancers of the head and neck, gastrointestinal tract, malignant melanoma, genital organs, endocrine organs, connective tissue, and haematological malignancies. Among these, there was evidence of differential associations with BMI between subtypes of gastric cancer, small intestine cancer, cervical cancer, and lymphoid neoplasms (P values for heterogeneity in HRs <0.05). The HR (95% confidence interval) per 5 kg/m² higher BMI was 1.17 (1.15–1.20) in men and 1.13 (1.11–1.15) in women for potential obesity-related cancers (51,690 cases), and 1.24 (1.22–1.26) in men and 1.12 (1.11–1.13) in women for established obesity-related cancers (84,384 cases). Interpretation: This study suggests a large number of potential obesity-related cancers could be added to already established ones. Importantly, the magnitudes of the associations were largely comparable to those of the already established obesity-related cancers. We also provide evidence of specific cancer subtypes driving some associations with BMI. Studies accounting for cancer-specific confounders are needed to confirm these findings.

The aim of this randomized controlled study was to explore if an intervention with biofeedback training in combination with ergonomic discussions, could improve working technique and work postures, and reduce pain intensity and perceived exertion in young adult computer users with ongoing neck and upper extremity symptoms. 39 participants were divided into an intervention group and a control group. The intervention consisted of 4 sessions during a three-month period. Working technique, working postures, rated perceived exertion, pain intensity, and duration of computer use were measured at baseline and follow ups after 6 and 12 months. The intervention did not significantly improve working technique and working postures, nor reduce pain intensity and perceived exertion in the intervention group compared to the control group. However, there was a statistically significant reduction in reported pain intensity in the neck/shoulder for the whole group. Also, there was a trend that time spent with computer work without breaks was more reduced in the intervention group than in the control group.