Exposure to benzene and other hydrocarbons and risk of bladder cancer among male offshore petroleum workers

BACKGROUND

Occupational exposures constitute the second leading cause of urinary bladder cancer after tobacco smoking. Increased risks have been found in the petroleum industry, but high-quality exposure data are needed to explain these observations.

METHODS

Using a prospective case-cohort design, we analysed 189 bladder cancer cases (1999-2017) and 2065 randomly drawn non-cases from the Norwegian Offshore Petroleum Workers cohort. Cases were identified in the Cancer Registry of Norway, while work histories (1965-1998) and lifestyle factors were recorded by questionnaire at baseline (1998). Occupational petroleum-related hydrocarbon exposures were assessed by expert-developed job-exposure matrices. Hazard ratios were estimated by weighted Cox-regressions, adjusted for age, tobacco smoking, education, and year of first employment, and with lagged exposures.

RESULTS

Increased risks were found in benzene-exposed workers, either long-term exposure (≥18.8 years, HR = 1.89, 95% CI: 1.14-3.13; p-trend = 0.044) or high-level cumulative benzene exposure (HR = 1.60, 95% CI: 0.97-2.63; p-trend = 0.065), compared with the unexposed. Associations persisted with 20-year exposure lag. No associations were found with skin or inhalation exposure to crude oil, mineral oil (lubrication, hydraulics, turbines, drilling), or diesel exhaust.

CONCLUSIONS

The results suggest that exposures in the benzene fraction of the petroleum stream may be associated with increased bladder cancer risk.

Night shift work and risk of aggressive prostate cancer in the Norwegian Offshore Petroleum Workers (NOPW) cohort

BACKGROUND

Night shift work may acutely disrupt the circadian rhythm, with possible carcinogenic effects. Prostate cancer has few established risk factors though night shift work, a probable human carcinogen, may increase the risk. We aimed to study the association between night shift work and chlorinated degreasing agents (CDAs) as possible endocrine disrupters in relation to aggressive prostate cancer as verified malignancies.

METHODS

We conducted a case-cohort study on 299 aggressive prostate cancer cases and 2056 randomly drawn non-cases in the Norwegian Offshore Petroleum Workers cohort (1965-98) with linkage to the Cancer Registry of Norway (1953-2019). Work history was recorded as years with day, night, and rollover (rotating) shift work, and CDA exposure was assessed with expert-made job-exposure matrices. Weighted Cox regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for aggressive prostate cancer, adjusted for education and year of first employment, stratified by 10-year birth cohorts, and with 10, 15, and 20 years of exposure lag periods.

RESULTS

Compared with day work only, an increased hazard of aggressive prostate cancer (HR = 1.86, 95% CI 1.18-2.91; P-trend = 0.046) was found in workers exposed to ≥19.5 years of rollover shift work. This persisted with longer lag periods (HR = 1.90, 95% CI 0.92-3.95; P-trend = 0.007). The exposure-hazard curve for a non-linear model increased linearly (HRs ≥1.00) for 18-26 years of rollover shift work. No association was found with CDA exposure.

CONCLUSIONS

Long-term exposure to rollover shift work may increase the hazard of aggressive prostate cancer in offshore petroleum workers.

Use of antihypertensive drugs and risk of cutaneous melanoma: a nationwide nested case-control study

Background

Most antihypertensives can induce dermal photosensitivity, which may increase melanoma risk. However, corroborating evidence is limited. We examined the associations between use of antihypertensives and melanoma risk.

Methods

A nationwide nested case-control study was conducted using data from the Cancer Registry of Norway, the National Registry and the Norwegian Prescription Database in 2004–15. Ten controls were randomly selected for each melanoma case, matched on sex and birth year. The study included 12 048 cases and 117 895 controls. We estimated rate ratios (RRs) with 95% confidence intervals (CIs). All analyses were adjusted for ambient ultraviolet radiation (UVR). We additionally performed active comparator analyses, and sensitivity analyses by only including new users, distinguishing between exclusive and mixed users, allowing for different latency periods, and subgroup analyses by melanoma subtype and clinical stage.

Results

Compared with non-use, we observed a slightly increased melanoma risk in users of diuretics (RR 1.08, CI 1.01–1.15), calcium-channel blockers (RR 1.10, CI 1.04–1.18) and drugs affecting the renin-angiotensin system (RR 1.10, CI 1.04–1.16), but not for beta blockers (RR 0.97, CI 0.92–1.03). We found no heterogeneity of associations by melanoma subtype or clinical stage and no dose-response relationship between the cumulative defined daily doses (DDDs) and melanoma. No interaction was found between cumulative DDDs and ambient UVR.

Conclusions

Weak associations, with lack of a dose-response relationship and lack of interactions with ambient UVR, in the DDD analysis in this nationwide study do not support a causal relationship between antihypertensives and melanoma risk.

Cancer epidemiology in practice: Working notes on cancer history-based selection and censoring

Leon A.M. Berge, Tom K. Grimsrud, Ronnie Babigumira, Nathalie C. Støer, Nita K. Shala, Marit B. Veierød and Jo S. Stenehjem: Cancer epidemiology in practice: Working notes on cancer history-based selection and censoring

Total late effect burden in long-term lymphoma survivors after highdose therapy with autologous stem-cell transplant and its effect on health-related quality of life

Lymphoma survivors after high-dose therapy with autologous stem-cell transplant (HDT-ASCT) are at risk of several late effects, which might impair their health-related quality of life (HRQoL). We assessed the total late effect burden in this population, and how it affects HRQoL. All lymphoma survivors treated with HDT-ASCT as adults in Norway between 1987 and 2008 were identified, and 271 (68%) attended both a comprehensive clinical assessment and completed a questionnaire. Severity of 45 conditions in 12 organ-system categories were graded as mild, moderate, severe or life-threatening, according to a modified version of CTCAEv4.03. At a median of 8 years after HDT-ASCT, 98% of survivors had at least one moderate or more severe late effect and 56% had severe or life-threatening late effects. Fourteen percent had low, 39% medium and 47% high late effect burden, defined as having moderate or more severe late effects in 0-1, 2-3 and >3 organsystems, respectively. Female sex, increasing age, B-symptoms at diagnosis and >1 treatment line prior to HDT-ASCT were independently associated with having high late effect burden. The survivors had significantly poorer physical and mental HRQoL assessed by the Short Form-36 compared to age- and sex-matched controls. The prevalence of poor physical and mental HRQoL increased with higher late effect burden (both P<0.001), and the low burden group had better physical HRQoL than controls (P<0.001). In conclusion, lymphoma survivors after HDT-ASCT have impaired HRQoL, seemingly driven by a high late effect burden. This highlights the importance of prevention, regular assessments for early detection and treatment of late effects and modifiable risk factors.

Craniofacial and dentoalveolar morphology in individuals with Prader-Willi syndrome: a case-control study

BACKGROUND

Prader-Willi syndrome (PWS) is a complex multisystem genetic disorder with distinct genetic and clinical features. Among other clinical symptoms, PWS is characterized by severe infantile hypotonia with feeding problems, childhood onset hyperphagia, obesity, scoliosis, short stature combined with growth hormone deficiency and developmental delay. PWS is associated with facial dysmorphology, orofacial dysfunction, oral abnormalities, low salivary flow and subsequent severe tooth wear. Little is known about the craniofacial growth direction or dental and skeletal relationships in individuals with PWS in different ages. The purpose of this study was to assess the craniofacial and dentoalveolar characteristics and to investigate the craniofacial growth direction separately in children, young adults and adults with PWS, using a cephalometric analysis of lateral cephalograms.

RESULTS

Lateral cephalograms of 42 individuals with a confirmed genetic diagnosis of PWS were analysed and divided into three groups according to their age: Children (< 12 years), young adults (12-20 years) and adults (> 20 years). Cephalometric variables were compared between PWS patients and controls by age and sex. Significant deviations and distinct craniofacial patterns were found in children, young adults and adults with PWS compared with the control group. Children showed retrognatic mandible with a skeletal class II relationship, posterior growth direction and longer anterior face height. The young adults had smaller cranial base angle, a skeletal class II pattern and a higher anterior lower face than the control group. Adults with PWS had a prognathic mandible, skeletal class III relationship with anterior growth direction, more retroclined lower incisors and proclined upper incisors than the controls. Similar results were found when comparing the three groups with PWS; the adults had a prognathic mandible, skeletal class III pattern and anterior growth direction. Children had a retropositioned mandibula, skeletal class II relationship and posterior growth direction.

CONCLUSION

This study may contribute to a better understanding of the craniofacial growth pattern in children, young adults and adults with PWS and may have a clinical importance when planning dental treatment, such as prosthodontics and/or orthodontics.

Pneumonitis and fibrosis after breast cancer radiotherapy: occurrence and treatment-related predictors

BACKGROUND

Radiation pneumonitis (RP) and radiation fibrosis (RF) are common side effects after breast cancer (BC) radiotherapy (RT). However, there is a great variation in the frequency of RP and RF. This study presents the occurrence of- and the treatment-related predictors for RP and RF. Further, physician- and patient-reported pulmonary symptoms during the first year after postoperative RT for BC are demonstrated.

MATERIALS AND METHODS

From 2007 to 2008, 250 BC patients referred for postoperative RT were included in a prospective cohort study and followed during the first year after RT. High-resolution computed tomography of the lungs and symptom registration were performed before RT and 3, 6, and 12 months after RT. Patient-reported symptoms were registered by standard quality of life questionnaires. Logistic regression analyses were applied to estimate treatment-related predictors for radiological RP (rRP), clinical RP (cRP), radiological RF (rRF), and clinical RF (cRF).

RESULTS

The occurrence of rRP and cRP at three months was 78% and 19%, while 12 months after RT rRF and cRF was 89% and 16%, respectively; all reported as grade 1. In multivariable analyses, mastectomy predicted cRP at three months (OR = 2.48, p = .03) and cRF at six months, ipsilateral lung volume receiving 20 Gray or more (V20), V30, and mean lung dose (MLD) predicted rRP at six months (OR = 1.06, p = .0003; OR = 1.10, p = .001; and OR = 1.03, p = .01, respectively). Endocrine treatment predicted cRF at 12 months (OR = 2.48, p = .02). Physicians reported significant more dyspnea at 3 months (p = .003) and patients reported 'a little dyspnea' more at 3 and 12 months compared to baseline (p = .007).

CONCLUSION

RP and RF are prevalent in the first year after BC radiation. Mastectomy predicted cRP at three months. V20, V30, D25, and MLD predicted rRP at 6 months, and endocrine treatment predicted cRF at 12 months. Patients and physicians reported dyspnea differently.

Prediagnostic Serum 25-Hydroxyvitamin D and Mortality Among Bladder Cancer Patients in the Janus Serum Bank Cohort

Purpose

Circulating 25-hydroxyvitamin D (25(OH)D) is inversely associated with overall cancer mortality and selected cancers, while for urothelial bladder cancer (BC) this relationship is unclear. We aimed to examine the association between 25(OH)D and BC mortality.

Materials and Methods

We used prediagnostic serum from 378 BC cases within the population-based Janus Cohort. Cox regression models estimated hazard ratios (HRs), with 95% confidence intervals (CIs), for the association between 25(OH)D and BC-specific and all-cause mortality. Restricted cubic splines were assessed to examine non-linear risk associations. Analyses were stratified by tumor invasiveness (non-muscle invasive BC (NMIBC) and muscle invasive BC (MIBC)). Additionally, the association between 25(OH)D and all-cause mortality was assessed for 378 cancer-free matched controls.

Results

25(OH)D deficiency (<50 nmol/L) was associated with higher BC-specific mortality (HR 1.87, 95% CI 1.10-3.20), when compared with insufficient levels (50-74 nmol/L). Stratification by tumor invasiveness revealed that this result was evident for NMIBC only, both with respect to BC-specific mortality (HR 2.84, 95% CI 1.14-7.12) and all-cause mortality (HR 1.97, 95% CI 1.06-3.65). No association between 25(OH)D levels and all-cause mortality was found in cancer-free controls.

Conclusion

25(OH)D deficiency (<50 nmol/L) prior to a BC diagnosis was associated with increased risk of BC-specific mortality, when compared to insufficient levels (50-74 nmol/L). The results were evident among NMIBC patients only, suggesting a more critical role of vitamin D deficiency in an early stage of the disease.

Vitamin D and Vitamin D-binding protein and risk of bladder cancer: A nested case-control study in the Norwegian Janus Serum Bank Cohort

Background

 High circulating levels of vitamin D (25(OH)D) are suggested to reduce the risk of urinary bladder cancer (BC), but the evidence is weak, and several studies lack sufficient adjustment for potential confounders (e.g., smoking, body mass index (BMI), and physical activity). Moreover, few studies have investigated the role of vitamin D‐binding protein (DBP) in this context. We conducted a matched nested case–control study including 378 cases and 378 controls within the Norwegian population‐based Janus cohort, using serum collected 5–41 years prior to diagnosis, to study 25(OH)D and BC risk, by taking circulating DBP into account.

Methods

Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs), for 25(OH)D, DBP, and the molar ratio of 25(OH)D:DBP, an estimate of unbound (free) 25(OH)D levels. We adjusted for smoking (status and pack‐years), BMI, physical activity, education and (mutually) for 25(OH)D and DBP. Restricted cubic splines were employed to examine nonlinear associations.

Results

High optimal levels of circulating 25(OH)D (≥100 nmol/L) (HR 0.35, 95% CI 0.19–0.64) were associated with decreased BC risk, when compared with insufficient concentrations (50–74 nmol/L). This association was less pronounced for optimal levels (75–99 nmol/L) (HR = 0.69, 95% CI 0.47–1.01). Moreover, estimated free 25(OH)D, was associated with decreased BC risk for molar ratio 17–21 (HR 0.66, 95% CI 0.44–0.97) and ≥22 (HR 0.50, 95% CI 0.29–0.82), compared to molar ratio 11–16. The HR function for BC risk was not linear, rather reversed u‐shaped, with the highest HR at 62.5 nmol/L and 13.5 molar ratio, respectively.

Conclusion

High levels of total and estimated free 25(OH)D were associated with reduced risk of BC, compared with insufficient concentrations. DBP was not associated with BC risk. We did not observe any impact of DBP or any of the studied lifestyle factors on the association between 25(OH)D and BC.

Ultraviolet radiation and risk of cutaneous melanoma and squamous cell carcinoma in males and females in the Norwegian Offshore Petroleum Workers cohort

BACKGROUND

Increased risk of cutaneous melanoma and squamous cell carcinoma (SCC) has been reported among petroleum workers, but few studies include females, exposure data on ultraviolet radiation (UVR), and potential confounding factors. We aimed to examine UVR exposure in relation to risk of melanoma and SCC among male and female offshore petroleum workers. We also examined the association between UVR exposure and melanoma (Breslow) thickness.

METHODS

The Norwegian Offshore Petroleum Workers (NOPW) cohort (n = 27,917) holds information on sunbathing, indoor tanning, sunburns, sunscreen use, and other lifestyle factors recorded in 1998. Linkage to the Cancer Registry of Norway gave information on cancer diagnosis through 2017. We used Cox and logistic regression to estimate hazard ratios (HRs) of skin cancer and odds ratios (OR) of thick (≥1 mm) melanomas, respectively, with 95% confidence intervals (CIs).

RESULTS

Melanoma risk increased with increasing frequency of sunbathing after age 20 (ptrend  = 0.031), sunburn average intensity (ptrend  = 0.028), and sunscreen use (HR = 2.16; 95% CI: 1.42 -3.27 for almost always vs. never/rarely). The risk of thick melanoma was inversely associated with sunbathing frequency after age 20 (OR = 0.38; 95% CI: 0.16 - 0.90 for ≥4 weeks/year vs. 1 week/year). SCC risk increased with increasing frequency of indoor tanning after age 20 (HR = 2.72; 95% CI: 1.22 - 6.05 for ≥3 times/months vs. never), sunburn average intensity (ptrend  < 0.001), and sunscreen use (ptrend  < 0.001).

CONCLUSIONS

Our results support associations between UVR exposure and skin cancer risk in male and female offshore petroleum workers. This occupational group may be especially relevant for targeted sun protection advice.

Genetic testing is essential for initiating statin therapy in children with familial hypercholesterolemia: Examples from Scandinavia

BACKGROUND AND AIMS

In familial hypercholesterolemia (FH), statin treatment should be considered from 8 to 10 years of age, but the prevalence of statin use among children is not known.

METHODS

Statin use (2008-2018) among children aged 10-14 and 15-19 years was obtained from the national prescription databases in Norway, Sweden and Denmark. We assumed that all statin users in these age groups had FH, and that the estimated prevalence of FH is 1 in 250 inhabitants. Changes in prevalence rates of statin use between 2008 and 2018 by country, age and sex were estimated using the Joinpoint Regression Program version 4.8.0.1. Differences in prevalence rate ratio each year between countries were analyzed using Poisson regression.

RESULTS

Among children aged 10-14 years, there was a significant increase in statin use in Norway and Denmark between 2008 and 2018, while in Sweden an increase was only seen after 2014. Among children aged 15-19 years, an increase in statin use was only observed in Norway and Sweden between 2008 and 2018. Statin use was significantly more prevalent in Norway than in Sweden and Denmark each year, and in 2018 the proportion of children using statins was 4-5 times (10-14 years) and 3 times (15-19 years) higher in Norway compared with Sweden and Denmark. In 2018 in Norway, 19% and 35% of children aged 10-14 years and 15-19 years estimated to have FH used statins respectively; corresponding percentages in Sweden were 4.5% and 10%, and in Denmark 3% and 12%. In Norway, the increase in statin use between 2008 and 2018 roughly corresponded to the increase in children with genetically verified FH.

CONCLUSIONS

Between 2008 and 2018, statin use increased in children aged 10-19 years in Norway, Sweden and Denmark, but with large differences between the countries; statin use was 3-5 times more prevalent in Norway than in Sweden and Denmark, which may be due to a more widespread use of genetic testing for FH in Norway.

Lifestyle associated factors and risk of urinary bladder cancer: A prospective cohort study from Norway

A number of lifestyle associated factors, such as high body mass index (BMI), low physical activity, and related metabolic disorders, are associated with increased risk of cancer at several sites. For urinary bladder cancer (BC), such studies show inconsistent results, which could result from inadequate adjustment for smoking and occupational exposure. In the population‐based Janus Cohort (n = 292 851), we investigated the independent and combined impact of BMI, physical activity, blood pressure, and blood lipids on the risk of BC, by thorough adjustment for smoking and potential occupational exposure. We used cox proportional hazard regression to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) for the associations between the lifestyle associated factors and BC risk. The associations observed were dependent on smoking status and gender. Among men, diastolic blood pressure (DBP) (HR 1.07, 95% CI 1.02‐1.12) and systolic blood pressure (SBP) (HR 1.04, 95% CI 1.01‐1.07) were positively associated with BC risk. Stratification by smoking status revealed a positive association between DBP and BC risk in never smokers (HR 1.14, 95% CI 1.00‐1.30), while no association was seen for current and former smokers. A risk score, integrating information across the lifestyle factors was positively associated with BC risk in men (p_trend = 0.043). In women, physical activity was associated with a decreased BC risk, but only among never smokers (HR 0.65, 95% CI 0.45‐0.94). In conclusion, relations between lifestyle associated factors and BC risk were most evident in never smokers, suggesting that smoking dominates the relation in current smokers.

Use of Antidepressants and Risk of Cutaneous Melanoma: A Prospective Registry-Based Case-Control Study

Purpose

Melanoma is the cancer with the most rapidly rising incidence rate in Norway. Although exposure to ultraviolet radiation (UVR) is the major environmental risk factor, other factors may also contribute. Antidepressants have cancer inhibiting and promoting side effects, and their prescription rates have increased in parallel with melanoma incidence. Thus, we aimed to prospectively examine the association between use of antidepressants and melanoma by using nation-wide data from the Cancer Registry of Norway, the National Registry, the Norwegian Prescription Database and the Medical Birth Registry of Norway.

Patient and Methods

All cases aged 18–85 with a primary cutaneous invasive melanoma diagnosed during 2007–2015 (n=12,099) were matched to population controls 1:10 (n=118,467) by sex and year of birth using risk-set sampling. We obtained information on prescribed antidepressants and other potentially confounding drug use (2004–2015). Conditional logistic regression was used to estimate adjusted rate ratios (RRs) and 95% confidence intervals (CIs) for the association between overall and class-specific use of antidepressants and incident melanoma.

Results

Compared with ≤1 prescription, ≥8 prescriptions of antidepressants overall were negatively associated with melanoma (RR 0.81 CI 0.75–0.87). Class-specific analyses showed decreased RRs for selective serotonin reuptake inhibitors (RR 0.82 CI 0.73–0.93) and mixed antidepressants (RR 0.77 CI 0.69–0.86). The negative association was found for both sexes, age ≥50 years, residential regions with medium and highest ambient UVR exposure, all histological subtypes, trunk, upper and lower limb sites and local disease.

Conclusion

Use of antidepressants was associated with decreased risk of melanoma. There are at least two possible explanations for our results; cancer-inhibiting actions induced by the drug and less UVR exposure among the most frequent users of antidepressants.

Challenges in assessing the sunscreen-melanoma association

Whether sunscreen use affects melanoma risk has been widely studied with contradictory results. To answer this question we performed a systematic review of all published studies, accounting for sources of heterogeneity and bias. We searched for original articles investigating the sunscreen‐melanoma association in humans to February 28, 2018. We then used random‐effects meta‐analysis to combine estimates of the association, stratified by study design. Stratified meta‐analysis and meta‐regression were used to identify sources of heterogeneity. We included 21,069 melanoma cases from 28 studies published 1979–2018: 23 case–control (11 hospital‐based, 12 population‐based), 1 ecological, 3 cohort and 1 randomised controlled trial (RCT). There was marked heterogeneity across study designs and among case–control studies but adjustment for confounding by sun exposure, sunburns and phenotype systematically moved estimates toward decreased melanoma risk among sunscreen users. Ever‐ vs. never‐use of sunscreen was inversely associated with melanoma in hospital‐based case–control studies (adjusted odds ratio (OR) = 0.57, 95%confidence interval (CI) 0.37–0.87, p_{heterogeneity} < 0.001), the ecological study (rate ratio = 0.48, 95%CI 0.35–0.66), and the RCT (hazard ratio (HR) = 0.49, 95%CI 0.24–1.01). It was not associated in population‐based case–control studies (OR = 1.17, 95%CI 0.90–1.51, p_{heterogeneity} < 0.001) and was positively associated in the cohort studies (HR = 1.27, 95%CI 1.07–1.51, p_{heterogeneity} = 0.236). The association differed by latitude (p_interaction = 0.042), region (p_interaction = 0.008), adjustment for naevi/freckling (p_interaction = 0.035), and proportion of never‐sunscreen‐users (p_interaction = 0·012). Evidence from observational studies on sunscreen use and melanoma risk was weak and heterogeneous, consistent with the challenges of controlling for innate confounding by indication. The only RCT showed a protective effect of sunscreen.

What's new?

Effectiveness of sunscreen in reducing UV‐induced skin damage has been proven in experimental studies, but effectiveness in reducing melanoma in humans remains inconclusive. This is the first meta‐analysis to analyze data from four study designs, stratify hospital‐ and population‐based case–control studies, and include as many as five prospective studies. Evidence from observational studies on the sunscreen‐melanoma association was heterogeneous, consistent with the challenges of controlling for innate confounding by indication. The only randomized controlled trial showed a protective effect. Public health recommendations should place greater emphasis on the proper use of sunscreen in conjunction with other means of sun protection.

Obstructive and restrictive pulmonary dysfunction in long-term lymphoma survivors after high-dose therapy with autologous stem cell transplantation

BACKGROUND

Obstructive and restrictive dysfunction in long-term lymphoma survivors (LSs) after high-dose therapy with autologous stem-cell transplantation (HDT-ASCT) has not been addressed systematically previously.

MATERIAL AND METHODS

LSs treated in Norway 1987-2008 with HDT-ASCT who performed spirometry, measurement of static lung volumes and echocardiography 2012-2014 at either Oslo or St. Olavs University Hospitals was eligible. Smoking data were recorded by questionnaire. Treatment data were collected from medical records or hospital databases. Factors associated with obstructive and restrictive impairments (dichotomous outcomes) were examined by Poisson regression. Linear regression with the margins post-estimation command was used to derive adjusted mean values of forced expiratory volume in 1 s (FEV₁). We used the normative reference data recommended by the European Respiratory Society for calculating percent predicted values.

RESULTS

A total of 226 LSs were studied, of whom 11.5 and 5.8% had obstructive and restrictive impairment, respectively. For women and men, mean FEV₁ was 2.31 and 3.34 l corresponding to 11.4%- and 11.1%-points below that predicted from norms, respectively. In multivariable regression analyses, cumulative doxorubicin dose (400-775 mg/m²) and current smoking were associated with increased risk of obstructive impairment, and chest RT (>13-66 Gy) was associated with increased risk of restrictive impairment. Currently smoking LSs within the highest doxorubicin category (400-775 mg/m²), had the lowest adjusted mean FEV₁.

CONCLUSIONS

Despite intensive cancer treatment, our analysis showed modest reductions in obstructive parameters among long-term LSs after HDT-ASCT compared to normative reference data. To limit obstructive impairments in LSs after HDT-ASCT, we suggest that targeted smoking-cessation advice is directed towards patients who have received high cumulative doses of doxorubicin.

Adiposity, physical activity, and risk of hypertension: prospective data from the population-based HUNT Study, Norway

Adiposity and inactivity have been associated with increased risk of hypertension. However, reports on the joint effect of these two risk factors in relation to hypertension are scarce and their interaction poorly understood. We prospectively examined both independent and joint effects of measured body mass index (BMI) and self-reported physical activity on the risk of hypertension. We conducted a longitudinal study of 11,238 men and 15,301 women who participated in the Nord-Trøndelag Health Study (HUNT) in Norway. Poisson regression was used to estimate adjusted risk ratios (RRs) of hypertension (≥140/90 mmHg) according to BMI and physical activity. BMI was positively associated with risk of hypertension in both sexes (P_trends < 0.001), whereas the independent effect of physical activity was less clear. Obese men who reported no physical activity had a RR of 1.50 (95% confidence interval (CI): 1.27-1.77) compared to normal weight men with a high activity level, whereas obese men who reported high activity levels had a RR of 1.16 (95% CI: 0.79-1.70). Correspondingly, obese and inactive women had a RR of 1.55 (95% CI: 1.35-1.77), whereas obese and highly active women had RRs of 1.41 (95% CI: 1.18-1.69). Our data suggest that high levels of physical activity could to some extent attenuate the unfavorable effect of adiposity on hypertension, particularly in men.

Anthropometric factors and cutaneous melanoma: Prospective data from the population-based Janus Cohort

The aim of the present study was to prospectively examine risk of cutaneous melanoma (CM) according to measured anthropometric factors, adjusted for exposure to ultraviolet radiation (UVR), in a large population-based cohort in Norway. The Janus Cohort, including 292,851 Norwegians recruited 1972-2003, was linked to the Cancer Registry of Norway and followed for CM through 2014. Cox regression was used to estimate hazard ratios (HRs) of CM with 95% confidence intervals (CIs). Restricted cubic splines were incorporated into the Cox models to assess possible non-linear relationships. All analyses were adjusted for attained age, indicators of UVR exposure, education, and smoking status. During a mean follow-up of 27 years, 3,000 incident CM cases were identified. In men, CM risk was positively associated with body mass index, body surface area (BSA), height and weight (all ptrends  < 0.001), and the exposure-response curves indicated an exponential increase in risk for all anthropometric factors. Weight loss of more than 2 kg in men was associated with a 53% lower risk (HR 0.47, 95% CI: 0.39, 0.57). In women, CM risk increased with increasing BSA (ptrend  = 0.002) and height (ptrend  < 0.001). The shape of the height-CM risk curve indicated an exponential increase. Our study suggests that large body size, in general, is a CM risk factor in men, and is the first to report that weight loss may reduce the risk of CM among men.

Adiposity, physical activity and risk of diabetes mellitus: prospective data from the population-based HUNT study, Norway

BACKGROUND

Physical activity may counteract the adverse effects of adiposity on cardiovascular mortality; however, the evidence of a similar effect on diabetes is sparse. This study examines whether physical activity may compensate for the adverse effect of adiposity on diabetes risk.

METHODS

The study population consisted of 38 231 individuals aged 20 years or more who participated in two consecutive waves of the prospective longitudinal Nord-Trøndelag Health Study in Norway: in 1984-1986 and in 1995-1997. A Poisson regression model with SEs derived from robust variance was used to estimate adjusted risk ratios of diabetes between categories of body mass index and physical activity.

RESULTS

Risk of diabetes increased both with increasing body mass (P_trend <0.001) and with decreasing physical activity level (P_trend <0.001 in men and 0.01 in women). Combined analyses showed that men who were both obese and had low activity levels had a risk ratio of 17 (95% CI 9.52 to 30) compared to men who were normal weight and highly active, whereas obese men who reported high activity had a risk ratio of 13 (95% CI 6.92 to 26). Corresponding analysis in obese women produced risk ratios of 15 (95% CI 9.18 to 25) and 13 (95% CI 7.42 to 21) among women reporting low and high activity levels, respectively.

CONCLUSIONS

This study shows that overweight and obesity are associated with a substantially increased risk of diabetes, particularly among those who also reported being physically inactive. High levels of physical activity were associated with a lower risk of diabetes within all categories of body mass index, but there was no clear evidence that being physically active could entirely compensate for the adverse effect of adiposity on diabetes risk.

Benzene exposure and risk of lymphohaematopoietic cancers in 25 000 offshore oil industry workers

BACKGROUND

The aim of this work was to examine the risk of lymphohaematopoietic (LH) cancer according to benzene exposure among offshore workers.

METHODS

Cancer registry data were used to identify 112 cancer cases diagnosed during 1999-2011 in a cohort of 24 917 Norwegian men reporting offshore work between 1965 and 1999. Analyses were conducted according to a stratified case-cohort design with a reference subcohort of 1661 workers. Cox regression was used to estimate hazard ratios with 95% confidence intervals, adjusted for other benzene exposure and smoking.

RESULTS

Most workers were exposed to benzene for <15 years. The upper range values of average intensity and cumulative exposure were estimated to 0.040 p.p.m. and 0.948 p.p.m.-years, respectively. Risks were consistently elevated among exposed workers for all LH cancers combined and for most subgroups, although case numbers were small and yielded imprecise risk estimates. There was evidence of dose-related risk patterns according to cumulative exposure for acute myeloid leukaemia (AML), multiple myeloma (MM) (P trends 0.052 and 0.024, respectively), and suggestively so for chronic lymphocytic leukaemia (CLL) according to average intensity (P trend 0.094).

CONCLUSIONS

Our results support an association between cumulative and intensity metrics of low-level benzene exposure and risk for AML, MM, and suggestively for CLL.

Self-reported Occupational Exposures Relevant for Cancer among 28,000 Offshore Oil Industry Workers Employed between 1965 and 1999

The objective of this study was to examine self-reported frequency of occupational exposure reported by 28,000 Norwegian offshore oil workers in a 1998 survey. Predictors of self-reported exposure frequency were identified to aid future refinements of an expert-based job-exposure-time matrix (JEM). We focus here on reported frequencies for skin contact with oil and diesel; exposure to oil vapor from shaker, to exhaust fumes, vapor from mixing chemicals used for drilling, natural gas, chemicals used for water injection and processing, and to solvent vapor. Exposure frequency was reported by participants as the exposed proportion of the work shift, defined by six categories, in their current or last position offshore (between 1965 and 1999). Binary Poisson regression models with robust variance were used to examine the probabilities of reporting frequent exposure (≥&frac14; vs. <&frac14; of work shift) according to main activity, time period, supervisory position, type of company, type of installation, work schedule, and education. Holding a non-supervisory position, working shifts, being employed in the early period of the offshore industry, and having only compulsory education increased the probability of reporting frequent exposure. The identified predictors and group-level patterns may aid future refinement of the JEM previously developed for the present cohort.