Bengt Järvholm

Obesity, Hypertension, and the Risk of Kidney Cancer in Men

BACKGROUND Obesity and hypertension have been implicated as risk factors for the development of renal-cell cancer. METHODS We examined the health records of 363,992 Swedish men who underwent at least one physical examination from 1971 to 1992 and were followed until death or the end of 1995. Men with cancer (renal-cell cancer in 759 and renal-pelvis cancer in 136) were identified by cross-linkage of data with the nationwide Swedish Cancer Registry. Poisson regression analysis was used to estimate relative risks, with adjustments for age, smoking status, body-mass index, and diastolic blood pressure. RESULTS As compared with men in the lowest three eighths of the cohort for body-mass index, men in the middle three eighths had a 30 to 60 percent greater risk of renal-cell cancer, and men in the highest two eighths had nearly double the risk (P for trend, <0.001). There was also a direct association between higher blood pressures and a higher risk of renal-cell cancer (P for trend, <0.001 for diastolic pressure; P for trend, 0.007 for systolic pressure). After the first five years of follow-up had been excluded to reduce possible effects of preclinical disease, the risk of renal-cell cancer was still consistently higher in men with a higher body-mass index or higher blood pressure. At the sixth-year follow-up, the risk rose further with increasing blood pressures and decreased with decreasing blood pressures, after adjustment for base-line measurements. Men who were current or former smokers had a greater risk of both renal-cell cancer and renal-pelvis cancer than men who were not smokers. There was no relation between body-mass index or blood pressure and the risk of renal-pelvis cancer. CONCLUSIONS Higher body-mass index and elevated blood pressure independently increase the long-term risk of renal-cell cancer in men. A reduction in blood pressure lowers the risk.

Obesity increases the risk of incident asthma among adults

The annual incidence of asthma in adults in northern Sweden has been estimated at 2.3 per thousand population. Risk factors for incident asthma among adults were studied in a case–referent study based on incident cases of asthma during 1995–1999. The healthcare providers reported suspected cases of incident asthma. After clinical examination, 309 (65% female) of 473 reported subjects were included. Inclusion criteria were a history of incident asthma (onset <12 months) and verified bronchial variability. Referents were randomly selected and stratified by age, sex and area of residence. The significant risk factors were hay fever, a family history of asthma, ex-smoking status and elevated body mass index (25.0–29.9 and ≥30). The risk factor pattern was similar for females and males, and increased body mass index was a significant risk factor for both males and females, as well as for allergic and nonallergic subjects. In conclusion, in addition to hay fever, a family history of asthma, allergic sensitisation and ex-smoking status, increased body mass index was a significant risk factor for incident asthma independent of sex and allergic status.

Comparative Health Impact Assessment of Local and Regional Particulate Air Pollutants in Scandinavia

Abstract The ongoing program Clean Air for Europe (CAFE) is an initiative from the EU Commission to establish a coordinated effort to reach better air quality in the EU. The focus is on particulate matter as it has been shown to have large impact on human health. CAFE requested that WHO make a review of the latest findings on air pollutants and health to facilitate assessments of the different air pollutants and their health effects. The WHO review project on health aspects of air pollution in Europe confirmed that exposure to particulate matter (PM), despite the lower levels we face today, still poses a significant risk to human health. Using the recommended uniform risk coefficients for health impact assessment of PM, regardless of sources, premature mortality related to long-range transported anthropogenic particles has been estimated to be about 3500 deaths per year for the Swedish population, corresponding to a reduction in life expectancy of up to about seven months. The influence of local sources is more difficult to estimate due to large uncertainties when linking available risk coefficients to exposure data, but the estimates indicate about 1800 deaths brought forward each year with a life expectancy reduction of about 2–3 months. However, some sectors of the population are exposed to quite high locally induced concentrations and are likely to suffer excessive reductions in life expectancy. Since the literature increasingly supports assumptions that combustion related particles are associated with higher relative risks, further studies may shift the focus for abatement strategies. CAFE sets out to establish a general cost effective abatement strategy for atmospheric particles. Our results, based on studies of background exposure, show that long-range transported sulfate rich particles dominate the health effects of PM in Sweden. The same results would be found for the whole of Scandinavia and many countries influenced by transboundary air pollution. However, several health studies, including epidemiological studies with a finer spatial resolution, indicate that engine exhaust particles are more damaging to health than other particles. These contradictory findings must be understood and source specific risk estimates have to be established by expert bodies, otherwise it will not be possible to find the most cost effective abatement strategy for Europe. We are not happy with todays situation where every strategy to reduce PM concentrations is estimated to have the same impact per unit change in the mass concentration. Obviously there is a striking need to introduce more specific exposure variables and a higher geographical resolution in epidemiology as well as in health impact assessments.

Increased mortality in COPD among construction workers exposed to inorganic dust

The aim of this study was to find out if occupational exposure to dust, fumes or gases, especially among never-smokers, increased the mortality from chronic obstructive pulmonary disease (COPD). A cohort of 317,629 Swedish male construction workers was followed from 1971 to 1999. Exposure to inorganic dust (asbestos, man-made mineral fibres, dust from cement, concrete and quartz), gases and irritants (epoxy resins, isocyanates and organic solvents), fumes (asphalt fumes, diesel exhaust and metal fumes), and wood dust was based on a job-exposure matrix. An internal control group with “unexposed” construction workers was used, and the analyses were adjusted for age and smoking. When all subjects were analysed, there was an increased mortality from COPD among those with any airborne exposure (relative risk 1.12 (95% confidence interval (CI) 1.03–1.22)). In a Poisson regression model, including smoking, age and the major exposure groups, exposure to inorganic dust was associated with an increased risk (hazard ratio (HR) 1.10 (95% CI 1.06–1.14)), especially among never-smokers (HR 2.30 (95% CI 1.07–4.96)). The fraction of COPD among the exposed attributable to any airborne exposure was estimated as 10.7% overall and 52.6% among never-smokers. In conclusion, occupational exposure among construction workers increases mortality due to chronic obstructive pulmonary disease, even among never-smokers.

Fifteen-year follow-up of hand eczema: persistence and consequences

Background  Hand eczema is a skin disease often with a long‐lasting and relapsing course. The long‐term prognosis in the general population is unknown.

Perceived pain before and after three exercise programs--a controlled clinical trial of women with work-related trapezius myalgia.

Abstract The effect of exercise on neck–shoulder pain was studied in 103 women with work‐related trapezius myalgia randomized into three exercise groups and a control group. One group trained strength, the second muscular endurance and the third co‐ordination. The exercise groups met three times weekly for 10 weeks. Pain assessment was made on three visual analogue scales, indicating pain at present, pain in general and pain at worst. Pain thresholds were measured in the trapezius muscle with a pressure algometer. A pain drawing was completed. The rated pain decreased significantly (P<0.05) on the VAS describing pain at worst in the strength and endurance groups. Pressure sensitivity decreased significantly (P<0.05) in four triggerpoints in the exercise groups. No changes were seen in the extent of painful body area in any group. Comparison of exercisers (n=82) and controls (n=21) showed significantly larger pain reductions on VAS pain at present and VAS pain at worst among exercisers. All three exercise programs showed similar decreases of pain which indicates that the type of exercise is of less importance to achieve pain reduction.

DNA adducts and lung cancer risk : a prospective study.

Objectives were to investigate prospectively the ability of DNA adducts to predict cancer and to study the determinants of adducts, especially air pollutants. DNA adducts were measured in a case-control study nested in the European Prospective Investigation into Cancer and Nutrition (EPIC) investigation. Cases included newly diagnosed lung cancer (n = 115), upper respiratory cancers (pharynx and larynx; n = 82), bladder cancer (n = 124), leukemia (n = 166), and chronic obstructive pulmonary disease or emphysema deaths (n = 77) accrued after a median follow-up of 7 years among the EPIC former smokers and never-smokers. Three controls per case were matched for questionnaire analyses and two controls per case for laboratory analyses. Matching criteria were gender, age, smoking status, country of recruitment, and follow-up time. Individual exposure to air pollution was assessed using concentration data from monitoring stations in routine air quality monitoring networks. Leukocyte DNA adducts were analyzed blindly using 32P postlabeling technique. Adducts were associated with the subsequent risk of lung cancer, with an odds ratio (OR) of 1.86 [95% confidence interval (95% CI), 0.88-3.93] when comparing detectable versus nondetectable adducts. The association with lung cancer was stronger in never-smokers (OR, 4.04; 95% CI, 1.06-15.42) and among the younger age groups. After exclusion of the cancers occurring in the first 36 months of follow-up, the OR was 4.16 (95% CI, 1.24-13.88). A positive association was found between DNA adducts and ozone (O3) concentration. Our prospective study suggests that leukocyte DNA adducts may predict lung cancer risk of never-smokers. Besides, the association of DNA adduct levels with O3 indicates a possible role for photochemical smog in determining DNA damage.

Impaired lung function and lung cancer incidence in a cohort of Swedish construction workers

Background: Although impaired lung function in general has been associated with an increased risk of lung cancer, past studies typically have not attempted to investigate separately the obstructive and restrictive components of respiratory impairment. To deal with this question further, data from a large (n = 176 997) cohort of male Swedish construction workers, for whom spirometry measurements before follow-up were available, were analysed. Methods: Cancer incidence for 1971–2001 was obtained through linkage with the national cancer registry. Using a modification of the Global Initiative for Chronic Obstructive Lung Disease criteria for chronic obstructive pulmonary disease (COPD), subjects were classified into five categories of lung function: normal, mild COPD, moderate COPD, severe COPD and restrictive lung disease (RLD). Rate ratios (RR) and 95% confidence intervals (CI) for lung cancer across lung function categories were calculated using Poisson regression, adjusted for age and smoking. Other end points (histological types of lung cancer, non-lung tobacco-related cancers, other cancers, total mortality) were also investigated. Results: 834 incident cases of lung cancer were identified. Increased rates of lung cancer were observed for both COPD (mild: RR 1.5, 95% CI 1.2 to 1.9; moderate/severe: RR 2.2, 95% CI 1.8 to 2.7) and RLD (RR 2.0, 95% CI 1.6 to 2.5) relative to normal lung function. These associations did not meaningfully change on applying follow-up lag times of 5, 10 and 15 years after spirometry. When analysed by histological type, associations with both COPD and RLD were stronger for squamous cell carcinoma and small cell carcinoma, and weaker for adenocarcinoma. Both COPD and RLD were associated with increased rates of total mortality. Conclusions: Obstructive and restrictive impairments in lung function are associated with increased lung cancer risk.

Occupational exposure to particulate air pollution and mortality due to ischaemic heart disease and cerebrovascular disease.

Objectives: A growing number of epidemiological studies are showing that ambient exposure to particulate matter air pollution is a risk factor for cardiovascular disease; however, whether occupational exposure increases this risk is not clear. The aim of the present study was to examine whether occupational exposure to particulate air pollution increases the risk for ischaemic heart disease and cerebrovascular disease. Methods: The study population was a cohort of 176 309 occupationally exposed Swedish male construction workers and 71 778 unexposed male construction workers. The definition of exposure to inorganic dust (asbestos, man-made mineral fibres, dust from cement, concrete and quartz), wood dust, fumes (metal fumes, asphalt fumes and diesel exhaust) and gases and irritants (organic solvents and reactive chemicals) was based on a job-exposure matrix with focus on exposure in the mid-1970s. The cohort was followed from 1971 to 2002 with regard to mortality to ischaemic heart disease and cerebrovascular disease. Relative risks (RR) were obtained by the person-years method and from Poisson regression models adjusting for baseline values of blood pressure, body mass index, age and smoking habits. Results: Any occupational particulate air pollution was associated with an increased risk for ischemic heart disease (RR 1.13, 95% CI 1.07 to 1.19), but there was no increased risk for cerebrovascular disease (RR 0.97, 95% CI 0.88 to 1.07). There was an increased risk for ischaemic heart disease and exposure to inorganic dust (RR 1.07, 95% CI 1.03 to 1.12) and exposure to fumes (RR 1.05, 95% CI 1.00 to 1.10), especially diesel exhaust (RR 1.18, 95% CI 1.13 to 1.24). There was no significantly increased risk for cerebrovascular disease and exposure to inorganic dust, fumes or wood dust. Conclusions: Occupational exposure to particulate air pollution, especially diesel exhaust, among construction workers increases the risk for ischaemic heart disease.

People with high mercury uptake from their own dental amalgam fillings.

OBJECTIVES--To describe people with high mercury (Hg) uptake from their amalgam fillings, and to estimate the possible fraction of the occupationally unexposed Swedish population with high excretion of urinary Hg. METHODS--Three case reports are presented. The distribution of excretion of urinary Hg in the general population was examined in pooled data from several sources. RESULTS--The three cases excreted 23-60 micrograms of Hg/day (25-54 micrograms/g creatinine), indicating daily uptake of Hg as high as 100 micrograms. Blood Hg was 12-23 micrograms/l, which is five to 10 times the average in the general population. No other sources of exposure were found, and removal of the amalgam fillings resulted in normal Hg concentrations. Chewing gum and bruxism were the probable reasons for the increased Hg uptake. Extrapolations from data on urinary Hg in the general population indicate that the number of people with urinary excretion of > or = 50 micrograms/g creatinine could in fact be larger than the number of workers with equivalent exposure from occupational sources. CONCLUSION--Although the average daily Hg uptake from dental amalgam fillings is low, there is a considerable variation between people; certain people have a high mercury uptake from their amalgam fillings.