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Aims: To study the importance of decreasing tobacco smoking on the occurrence of larynx cancer in men and women.

Methods: The incidence rates of larynx cancer in the Swedish population between 1970 and 2021 were retrieved from the Swedish Cancer Register for ages 50–84 years, stratified for sex, age and calendar year. Data on the population’s smoking habits was retrieved from surveys and from taxation on the sale of cigarettes. The occurrence of larynx cancer was compared to smoking habits, sex and age. The time trends were compared between larynx and lung cancer.

Results: Over the years, Swedish men and women have had different smoking habits, especially older persons during the 1970s. In 1963, the prevalence of current smokers in women 50–69 years was 11%, while it was 46% in men. Around 2020, less than 10% of men and women in all age groups were current smokers. However, men had higher incidence rates of larynx cancer than women, even when their smoking habits were similar. For example, men and women 60–64 years of age in 2017–2021 had similar smoking habits during their life but the relative risk of larynx cancer in men compared to women was 3.3 (95% CI 1.7–4.8). However, pipe smoking was much more common in men.

Conclusions: The study indicates that other causes than cigarette smoking have an impact on the occurrence of larynx cancer in Sweden. Pipe smoking and occupational exposure to carcinogenic materials such as asbestos may be underlying causes of the difference in cancer risk between Swedish men and women.

Objective: This paper discusses the failure and success of society to decrease the adverse health effects of asbestos exposure on workers’ health in relation to scientific knowledge.

Methods: The findings are based on a narrative literature review.

Results: Early warnings of the adverse health effects of workplace exposure to asbestos were published already in the 1930s. Serious health effects, such as malignancies and fibrosis due to occupational asbestos exposure, were highlighted in major medical journals and textbooks in late 1960s. New technologies could detect also asbestos fibers in the lung of non-occupational exposed persons in the 1970s. The first bans for using asbestos came in the early 1970s, and more general bans by authorities came in the 1980s and continue until today.

Conclusions: The rather late recognition of adverse effects of asbestos exposure in the general population and measures to decrease the exposure through more general bans came rather late. However, the very strong measures such as general bans in many countries have been a success. A Swedish study showed that the general ban and other measures have decreased the risk of malignancies due to occupational exposure. The effect of the bans on adverse effects in the general population has yet to be studied. Analysis of fibers in the lungs of persons born after the bans could be an efficient method.

Background: Oil refinery workers are exposed to benzene, which is a well-known cause of leukaemia, but results on leukaemia in oil refinery workers have been mixed, and the data on workers’ exposure is limited. Oil refinery workers are also exposed to asbestos and several studies have shown increased risk of mesothelioma.

Aim: The objective was to investigate cancer incidence, especially leukaemia, at low to moderate exposure to benzene in an update of a previous study of employees at three Swedish oil refineries.

Methods: Cancer incidence was followed up in 2264 men (1548 refinery operators) employed at three oil refineries in Sweden for at least one year. Job types and employment times were collected from complete company files. A retrospective assessment of the benzene exposure was performed by occupational hygienists in collaboration with the refineries using historic measurements as well as detailed information on changes in the industrial hygiene and technological developments. Cases of cancer were retrieved by a linkage with the Swedish Cancer Register through 35–47 years of follow-up and standardized incidence ratios (SIR) with 95% confidence intervals (CI) were calculated.

Results: In total, 258 tumors had occurred versus 240 expected (SIR 1.07; 95% CI 0.95–1.21). There were 10 cases of leukaemia, all in refinery operators (SIR 2.4; 95% CI 1.18–4.51). There were three cases of pleural mesothelioma, two of which in refinery operators. The mean estimated cumulative benzene exposure for the cases of leukaemia was 7.9 ppm-years (median 4.9, range 0.1–31.1). Discussion: The study suggests that low to moderate average cumulative benzene exposure increases the risk of leukaemia. Limitations include the modest number of cases and potential misclassification of exposure.

Conclusion: The present study indicated an increased risk of leukaemia in male oil refinery workers with low to moderate exposure to benzene.

Background: The objective is to estimate the importance of the decrease of smoking habits in Sweden for the occurrence of lung cancer.

Methods: The change in smoking habits in the general population was retrieved from surveys and on taxation of sale of cigarettes. We used data from the Swedish Cancer Register on incidence of lung cancer between 1970 and 2021, stratified for sex, age and cell type, and compared the occurrence overtime in ages between 40 and 84 years.

Results: The sale of cigarettes peaked in 1980 to 1800 cigarettes per person and decreased to 600 per person in 2021. The change in incidence rates of squamous cell cancer and other cell types varied over time, sex, and age in a pattern that partly seems to be explained by change in the prevalence of daily smokers. The incidence of adenocarcinoma was similar in men and women 1970–2021 and increased, e.g. for women and men 75–79 years of age from around 20 cases in early 1970s to around 120 cases per 100 000 person-years in the 2020s.

Conclusions: Our data indicate that the risk of lung cancer several years after smoking cessation is less favourable than previously studies have indicated. There is a similar increase in the incidence of adenocarcinoma in men and women which is hard to explain only with changing smoking habits. The change from non-filter to filter cigarettes in the 1960s–1970s may be a contributing factor.

Objective: Retinal detachment (RD) has been associated with exposure to heavy lifting. Many occupations within the construction industry are likely to involve lifting tasks. We investigated the association between occupational heavy lifting and rhegmatogenous RD in a retrospective cohort study of Swedish construction workers.

Methods: We studied Swedish construction workers who participated in an industry-wide health and safety program from 1971 to 1993. Individual occupation codes were linked to a job exposure matrix, assigning intensity of exposure to heavy lifting to each worker. The Swedish National Patient Register was used to identify cases of RD that occurred during follow-up through the end of 2012. We used Poisson regression modeling to calculate incidence rates of RD associated with heavy lifting, age and other covariates. A subcohort of those age ≤25 years at enrollment was studied to reduce bias from missing exposure information from work prior to enrollment.

Results: Of 256 241 construction workers, 17% were classified with high exposure to heavy lifting in their occupation. Within the cohort, 1588 cases of RD were identified. Average exposure intensity of heavy lifting was not associated with risk of RD. However, RD risk increased with increasing cumulative exposure to heavy lifting, both in the full cohort and subcohort of those who were ≤25 years old at entry into the construction-worker cohort.

Conclusion: Construction workers' risk of RD appeared to increase with time spent exposed to heavy lifting.

Denna rapport syftar till att uppdatera kunskapen om arbetsrelaterad dödlighet i Sverige utifrån två rapporter publicerade 2019 (Arbetsmiljöverket 2019a, 2019b). Där beräknades antalet dödsfall utgående från exponering för arbetsmiljöfaktorer i Sverige som hade betydelse för dödligheten under 2016. Genom en översiktlig analys av den vetenskapliga litteraturen har nu (fram till senhösten 2022) undersökts om sambanden mellan dödlighet och exponering förändrats. I uppdraget låg att särskilt fokusera på frågan om ett eventuellt samband mellan mobbning och självmord. I denna rapport beskrivs också översiktligt kunskap om hur man genom förebyggande åtgärder kan påverka den arbetsrelaterade dödligheten.

I den tidigare rapporten beskrevs att kunskapsläget var mer osäkert när det gäller sambanden mellan dödlighet och ihållande tungt fysiskt arbete respektive buller. De nyare studier som tillkommit gör inte att kunskapsläget påtagligt förändrats. Det har tillkommit välgjorda studier som indikerar ett samband mellan mobbning och självmord liksom ett samband mellan ohälsosam arbetsbelastning och självmord. Det är metodologiskt svårt att studera denna typ av samband och det behövs ytterligare studier innan sambanden kan anses etablerade. I den tidigare rapporten bedömdes antalet arbetsrelaterade dödsfall på grund av infektioner vara mycket lågt men under Covid-19 pandemin kan ett betydande antal arbetsrelaterade dödsfall ha inträffat. Ännu saknas tillförlitliga data för att beräkna antalet arbetsrelaterade dödsfall på grund av Covid-19 i Sverige. Studier från England och Wales tyder på att antalet arbetsrelaterade fall varierade ganska mycket över tid. Förutom personal inom hälso- och sjukvård var där särskilt buss- och taxiförare utsatta grupper liksom personal inom livsmedelsindustrin.

Studier av dödsolyckor visar att cirka 2 av 3 dödsolyckor under den senaste 10-årsperioden skett bland anställda i företag med mindre än 50 anställda. Metoder som utvecklades för att studera olyckor ur ett systemperspektiv, till exempel AcciMap eller STAMP förutsätter relativt stor kompetens och är tidskrävande. De bedöms huvudsakligen vara användbara för större organisationer. En svensk studie av exponering i arbetslivet för vissa kemiska faktorer talar för att personer som exponeras i allt högre utsträckning arbetar i mindre företag. För att påverka den arbetsrelaterade dödligheten på grund av dödsolyckor eller exponering för kemiska ämnen bör insatser riktas mot små- och medelstora företag där sådan exponering förekommer.

Idag bedrivs produktion ofta i värdekedjor, till exempel genom huvudentreprenör/underentreprenörer alternativt huvudleverantör/underleverantörer. Det finns kunskap som talar för att ett sätt att minska riskerna för arbetsrelaterad dödlighet är att lägga huvudansvaret för en god och säker arbetsmiljö på huvudentreprenör/huvudleverantör.

Objective: This study investigated the association between occupational physical activity (OPA) and resting blood pressure in a cohort of Swedish construction workers.

Methods: The final sample included 241,176 male construction workers. Occupations with low OPA were foremen and white-collar workers. The most frequent occupations in the medium OPA group were electricians, pipe workers, and machine operators, and in the high OPA group woodworkers, concrete workers, and painters.

Results: Mixed effects models showed higher systolic and lower diastolic blood pressure with higher OPA, but the associations varied depending on the year of participation and participant age as shown by significant interaction terms (OPA*age, OPA*calendar year, age*calendar year). Age-stratified linear regression analyses showed a pattern of slightly higher systolic (1.49, 95% confidence interval: 1.08-1.90 mmHg) and lower diastolic (0.89, 95% confidence interval: 0.65-1.13 mmHg) blood pressure when comparing low with high OPA, but not among the oldest age groups.

Conclusion: Despite a rather large contrast in OPA, the differences in systolic and diastolic blood pressure according to OPA were small.

Background: Prospective and detailed investigations of smoking and prostate cancer (PCa) risk and death are lacking.

Objective: To investigate prediagnosis smoking habit (status, intensity, duration, and cessation) as a risk factor, on its own and combined with body mass index (BMI), for PCa incidence and death.

Design, setting, and participants: We included 351 448 men with smoking information from five Swedish cohorts. Outcome measurements and statistical analysis: We used Cox regression to calculate hazard ratios (HRs) and confidence intervals (CIs) for PCa incidence (n = 24 731) and death (n = 4322).

Results and limitations: Smoking was associated with a lower risk of any PCa (HR 0.89, 95% CI 0.86–0.92), which was most pronounced for low-risk PCa (HR 0.74, 95% CI 0.69–0.79) and was restricted to PCa cases diagnosed in the prostate-specific antigen (PSA) era. Smoking was associated with a higher risk of PCa death in the full cohort (HR 1.10, 95% CI 1.02–1.18) and in case-only analysis adjusted for clinical characteristics (HR 1.20, 95% CI 1.11–1.31), which was a consistent finding across case groups (p = 0.8 for heterogeneity). Associations by smoking intensity and, to lesser degree, smoking duration and cessation, supported the associations for smoking status. Smoking in combination with obesity (BMI ≥30 kg/m²) further decreased the risk of low-risk PCa incidence (HR 0.40, 95% CI 0.30–0.53 compared to never smokers with BMI <25 kg/m²) and further increased the risk of PCa death (HR 1.49, 95% CI 1.21–1.84). A limitation of the study is that only a subgroup of men had information on smoking habit around the time of their PCa diagnosis.

Conclusions: The lower PCa risk for smokers in the PSA era, particularly for low-risk PCa, can probably be attributed to low uptake of PSA testing by smokers. Poor survival for smokers, particularly obese smokers, requires further study to clarify the underlying causes and the preventive potential of smoking intervention for PCa death.

Patient summary: Smokers have a higher risk of dying from prostate cancer, which further increases with obesity.

OBJECTIVE: The aim of this study was to assess the association between occupational biomechanical exposures and the occurrence of surgical treatment for subacromial impingement syndrome (SIS).

METHODS: A cohort of 220 295 male constructions workers who participated in a national occupational health surveillance program (1971-1993) were examined prospectively over a 16-year follow-up period (2001-2016) for surgically treated SIS. Worker job title, smoking status, height, weight, and age were registered on health examination. Job titles were mapped to 21 occupational groups based on tasks and training. A job exposure matrix (JEM) was developed with exposure estimates for each occupational group. Surgical cases were determined through linkage with the Swedish national in- and outpatient registers. Poisson regression was used to assess the relative risks (RR) for each biomechanical exposure.

RESULTS: The total incidence rate of surgically treated SIS over the 16-year observation period was 201.1 cases per 100 000 person-years. Increased risk was evident for workers exposed to upper-extremity loading (push/pull/lift) (RR 1.45-2.30), high hand grip force (RR 1.47-2.23), using handheld tools (RR 1.52-2.09), frequent work with hands above shoulders (RR 1.62-2.11), static work (RR 1.77-2.26), and hand-arm vibration (RR 1.78-2.13). There was an increased risk for SIS surgery for all occupational groups (construction trades) compared with white-collar workers (RR 1.56-2.61).

CONCLUSIONS: Occupational upper-extremity load and posture exposures were associated with increased risk for surgical treatment of SIS, which underlines the need for reducing workplace exposures and early symptom detection in highly exposed occupational groups.