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With an aging workforce and longer working lives, staying in physically demanding occupations is increasingly challenging, and the factors influencing perceived exertion are still poorly understood. Also, self-rated exertion may not correlate strongly with physiological measurements of physical strain at work, such as heart rate. Our study aimed to describe the physical strain experienced by senior workers in manual occupations using Borg's Rating of Perceived Exertion (RPE) scale and to explore associations between personal variables such as heart rate during work, age, physical fitness, and RPE ratings. We recruited workers aged 50 yr or older in manual occupations and collected data using questionnaires, physical examinations, field heart rate monitoring, and RPE ratings during work. Field heart rate monitoring was conducted using a chest band with a pulse sensor that transmitted data to a mobile application, and the first 6 h of recordings were used in subsequent analyses. Subjects were asked to simultaneously complete a diary at the end of each shift, rating the overall physical exertion for that day using the RPE scale, ranging from 6 (rest) to 20 (maximal physical exertion). Correlation between variables was determined using Spearman's rank correlation coefficient (r). A linear mixed model was used to investigate associations between personal variables and RPE ratings. The sample consisted of 126 subjects, aged 50 to 67 yr, of whom 76 (60.3%) were females. The participants were employed as construction workers, kitchen workers, cleaners, or assistant nurses. They rated perceived physical exertion on the RPE scale once daily in one to three workdays, resulting in a total of 250 workdays. The mean (SD) RPE rating was 12.1 (2.1). When stratified by sex, the mean (SD) RPE rating was 12.1 (2.2) among females and 12.0 (1.8) among males (P = 0.669). When stratified by occupational group, the mean (SD) was 11.9 (1.9) for construction workers, 12.1 (2.0) for kitchen workers, 12.4 (1.6) for cleaners, and 11.8 (2.8) for assistant nurses (P = 0.139 to 0.815). In total, 298 heart rate (HR) recordings were obtained during work with a mean (SD) HR of 89.4 (11.4) beats/min (range 54 to 125). There was a significant bivariate correlation between the RPE ratings and mean HR for the entire study population (r = 0.14; P = 0.025) as well as in the group of construction workers (r = 0.23; P = 0.042), but not for any other occupational groups (r = 0.04 to 0.25; P = 0.096 to 0.752). In the linear mixed model, using the RPE ratings as the dependent variable, the statistically significant (P < 0.05) estimated coefficients (SE) were as follows: mean heart rate (beats/min), 0.03 (0.01); very poor sleep quality, 3.38 (0.93); and high psychological stress, 2.62 (0.71). Age, body mass index, theoretical maximum oxygen consumption, and chronic pain ratings were not significantly associated with the RPE ratings. We conclude that senior workers in manual occupations reported that their work was somewhat hard in terms of physical exertion. Our study also indicates associations between mean heart rate, sleep quality, psychological stress, and RPE ratings.

Background: High concentrations of coarse particulate matter PM10 from road dust are a major air quality concern in Visby, Sweden. To mitigate these levels, local authorities replaced soft limestone with crushed granite as an anti-slip material starting in the winter of 2023/2024. This is a follow-up study evaluating the impact of this intervention on PM10 concentrations and the associated short-term respiratory health effects.

Methods: Daily counts of healthcare visits for respiratory diseases (ICD-10: J00–J99) and daily mean PM10 concentrations were analyzed using a quasi-Poisson regression model. This study compared the limestone period (2015–2019) with the granite period (2023–2025), stratified by season (winter/spring and summer/autumn) and age group (children 0–17 years and adults >17 years).

Results: The transition to crushed granite reduced peak PM10 concentrations during the spring. For adults, the relative risks for respiratory visits during winter/spring decreased during the granite period when compared to the limestone period (Wald p < 0.05). However, when considering that there were a majority of non-statistically significant differences when comparing the granite and limestone periods, these results should be interpreted with caution. Among children, more pronounced associations were observed during summer, although no significant differences in risk were detected between the limestone and granite periods.

Conclusions: Although the intervention effectively lowered particle mass concentrations, only minor changes were observed in the overall epidemiological pattern. This suggests that public health improvements may be limited by factors beyond total mass reduction, such as particle mineralogy or seasonal exposure dynamics.

Introduction: Associations between work-related musculoskeletal disorders (WMSDs) and awkward postures and repetitive movements have been established. Action levels for elevated arms, trunk flexion, and fast movements have been suggested. With today's prolonged working life, older workers in manual jobs may be at increased risk for WMSDs. The aim of this study was therefore to assess postural workload in older workers in four physically demanding occupational groups using technical measurements and compare the exposure of the groups with each other's and with the action level.

Methods: Postures and movements were measured for the right upper arm and the trunk using inertial measurement units (IMUs) during 3 workdays in construction workers (n = 35), kitchen workers (n = 37), cleaners (n = 27), and assistant nurses (n = 25), all over 50 years. Angle and angular velocity were computed, and time exceeding suggested angular cut-offs was assessed. Group mean and variance components within and between subjects were estimated in one-way random effect models. One-way ANOVA tests were conducted to compare exposure variables between the occupational groups.

Results: Construction workers spent more time with arms >60° than other occupational groups (7.9% vs. 4.4–5.6%) and >90° (2.8% vs. 1.0–1.3%). Across groups, a substantial share of days exceeded suggested action level for arm elevation >30° (8.0–24.6%) and >60° (6.3–22.7%). Cleaners had the highest 50th percentile trunk flexion (15.3°), while construction workers spent the most time with trunk flexion >45° (12.6%) and >60° (7.4%); exceedances of recommended levels occurred in up to 39% of days. Kitchen workers and cleaners exhibited more time with fast arm movements (31.8–35.6% vs. 23.9–24.0%). Considerable variability was observed both within and between individuals.

Conclusion: In the included occupational groups, in workers over 50 years, arm elevation and trunk flexion may often exceed recommended levels. Since the physical capacity is decreasing with age, this indicates elevated musculoskeletal risks, and there is a clear need for targeted ergonomic measures to support sustainable working lives.

Objective: To measure and determine the occupational cardiovascular workload and cardiovascular fitness among older employees (50 +) in four physically demanding occupational groups.

Methods: Health investigations, including aerobic capacity, were performed on 120 construction and kitchen workers, cleaners, and assistant nurses. Cardiovascular load was assessed over three working days using heart rate (HR) measurements. Data was processed for average loads (HR and Relative HR reserve (%HRR)) and measures describing variations in loads, such as time spent in different heart rate intensities.

Results: Participants’ mean age was 57 (SD 4.1) years, and 63% of the participants were female. The mean %HRR over occupational groups was 24.9% (SD 6.8). Of the participants, 43% had an average cardiovascular load above 24.5%HRR and 11% over 33%HRR. Depending on the work sector, 22–37% of the worktime was spent in intensities over 30%HRR, and 2–4% was spent in cardiovascular intensities over 50%HRR. The average VO2max was 33.2 (SD 8.2) ml/kg/min for all, for men 39.0 (SD 7.0), and for women 29.8 (SD 6.9).

Conclusion: We found a high mean cardiovascular load at work among the senior workers in all four work sectors, but low proportions of the worktime were spent in high intensity levels. Despite a high mean cardiovascular load at work, a high proportion of the workers had low cardiovascular fitness. Given the possible negative effects of occupational physical activity and to meet future demographic challenges, future interventions should aim to reduce physical loads and increase physical fitness in the workforce.

Aim: The burden of respiratory disease is great among children. This study aimed to examine the temporal relationship between hospitalisation for respiratory syncytial virus (RSV) and bacterial pneumonia.

Methods: A Swedish population-based cohort was created by combining data from the Swedish Medical Birth Register, the National Inpatient Register, the Cause of Death Register, the Total Population Register, and the Longitudinal Integration Database for Health Insurance and Labour Market Studies. Children born between 1998 and 2015 were included and followed for 2 years. We examined the temporal relationship between RSV hospitalisation and bacterial pneumonia using piecewise exponential models.

Results: The final cohort comprised 1 641 747 children, 48.5% were females. There were 23 632 RSV and 4722 bacterial pneumonia hospitalisations, with mean age of 137.8 and 424.2 days, respectively. RSV hospitalisation was associated with bacterial pneumonia with an adjusted incidence rate ratio (aIRR) of 3.18. The risk was highest in the first month after RSV hospitalisation, aIRR 11.19. The risk of bacterial pneumonia was elevated for 4 months after RSV hospitalisation and before RSV hospitalisation.

Conclusion: We found an increased risk for bacterial pneumonia hospitalisation in children hospitalised for RSV both before and after RSV hospitalisation, indicating a bidirectional relationship.

Background: Individuals with type 2 diabetes (T2D) have an increased risk of cognitive symptoms and Alzheimer's disease (AD). Mis-metabolism with aggregation of amyloid-β peptides (Aβ) play a key role in AD pathophysiology. Therefore, human studies on Aβ metabolism and T2D are warranted.

Objective: The objective of this study was to examine whether acute hyperglycemia affects plasma Aβ1-40 and Aβ1-42 concentrations in individuals with T2D and matched controls.

Methods: Ten participants with T2D and 11 controls (median age, 69 years; range, 66-72 years) underwent hyperglycemic clamp and placebo clamp (saline infusion) in a randomized order, each lasting 4 hours. Aβ1-40, Aβ1-42, and insulin-degrading enzyme (IDE) plasma concentrations were measured in blood samples taken at 0 and 4 hours of each clamp. Linear mixed-effect regression models were used to evaluate the 4-hour changes in Aβ1-40 and Aβ1-42 concentrations, adjusting for body mass index, estimated glomerular filtration rate, and 4-hour change in insulin concentration.

Results: At baseline, Aβ1-40 and Aβ1-42 concentrations did not differ between the two groups. During the hyperglycemic clamp, Aβ decreased in the control group, compared to the placebo clamp (Aβ1-40: p = 0.034, Aβ1-42: p = 0.020), IDE increased (p = 0.016) during the hyperglycemic clamp, whereas no significant changes in either Aβ or IDE was noted in the T2D group.

Conclusions: Clamp-induced hyperglycemia was associated with increased IDE levels and enhanced Aβ40 and Aβ42 clearance in controls, but not in individuals with T2D. We hypothesize that insulin-degrading enzyme was inhibited during hyperglycemic conditions in people with T2D.

Context: Adrenal insufficiency (AI) is usually diagnosed by low plasma cortisol levels following a short Synacthen test (SST). Most plasma cortisol is bound to corticosteroid-binding globulin, which is increased by estrogen in combined estrogen-progestin oral contraceptives (COCs). Women with AI using COCs are therefore at risk of having an apparently normal plasma cortisol level during SST, which would not adequately reflect AI.

Objective: To test whether salivary cortisol or cortisone during SST is more robust against the COC effect and to calculate the lower reference limits (LRLs) for these to be used as tentative diagnostic cutoffs to exclude AI.

Methods: Forty-one healthy women on COCs and 46 healthy women without exogenous estrogens performed an SST with collection of plasma and salivary samples at 0, 30, and 60 min after Synacthen injection. The groups were compared using regression analysis with age as covariate and the LRLs were calculated parametrically.

Results: SST-stimulated plasma cortisol levels were significantly higher in the COC group versus controls, while mean salivary cortisol and cortisone levels were slightly lower in the COC group. Importantly, COC use did not significantly alter LRLs for salivary cortisol or cortisone. The smallest LRL difference between groups was seen for salivary cortisone.

Conclusion: Salivary cortisol and especially salivary cortisone are considerably less affected by COC use than plasma cortisol during SST. Due to similar LRLs, a common cutoff for salivary cortisol and cortisone during SST can be used to exclude AI in premenopausal women irrespective of COC use.

Background: Daily air pollution levels are known to influence the number of patients with acute asthma. We investigated the short-term effects of air pollution exposure on the daily number of asthma medication purchases in the Greater Stockholm area, Sweden.

Methods: We conducted a time-series study with data on asthma medication purchases and daily mean values of particulate matter ≤10 µm (PM10), nitrogen oxides (NOx), and ozone during 2018-2019. We used nonlinear distributed lag quasi-Poisson regression models to estimate the associations between air pollution levels and medication purchases, adjusting for meteorological variables, pollen levels, day of the week, and long-term trends. The models established linear relationships between air pollutants and the outcome, and potential delayed effects were smoothed with a spline across a lag period of 2 weeks. We applied separate models for each municipality (n = 21) in Greater Stockholm, and calculated pooled estimates to achieve combined results for the whole region.

Results: We observed associations between daily levels of air pollution and purchases of asthma medications, most clearly for PM10. The pooled estimates of the relative risks for asthma medication purchases across all 21 municipalities associated with a 10 μg m-3increase in PM10the same day (lag 0) was 1.7% [95% confidence interval (CI): 1.2%, 2.1%], a cumulative increase of 4.6% (95% CI: 3.7%, 5.6%) over one week (lag 0-6), and a 6.5% (95% CI: 5%, 8%) increase over 2 weeks (lag 0-13). The corresponding pooled effect per 10 μg m-3increase in NOxand ozone were 2.8% (95% CI: 1.6%, 4.1%) and 0.7% (95% CI: 0%, 1.4%) over 2 weeks (lag 0-13), respectively.

Conclusions: Our study revealed short-term associations between air pollution, especially PM10, and purchases of asthma medications.

In the summer of 2018, Sweden experienced widespread wildfires, particularly in the region of Jämtland Härjedalen during the final weeks of July. We previously conducted an epidemiological study and investigated acute respiratory health effects in eight municipalities relation to the wildfire air pollution. In this study, we aimed to estimate the potential health impacts under less favorable conditions with different locations of the major fires. Our scenarios focused on the most intense plume from the 2018 wildfire episode affecting the largest municipality, which is the region’s only city. Combining modeled PM2.5 concentrations, gridded population data, and exposure–response functions, we assessed the relative increase in acute health effects. The cumulative population-weighted 24 h PM2.5 exposure during the nine highest-level days reached 207 μg/m3 days for 63,227 inhabitants. We observed a small number of excess cases, particularly in emergency unit visits for asthma, with 13 additional cases compared to the normal 12. Overall, our scenario-based health impact assessment indicates minor effects on the studied endpoints due to factors such as the relatively small population, limited exposure period, and moderate increase in exposure compared to similar assessments. Nonetheless, considering the expected rise in fire potential due to global warming and the long-range transport of wildfire smoke, raising awareness of the potential health risks in this region is important.