The APHEA 2 project investigated short-term health effects of particles in eight European cities. In each city associations between particles with an aerodynamic diameter of less than 10 microm (PM(10)) and black smoke and daily counts of emergency hospital admissions for asthma (0-14 and 15-64 yr), chronic obstructive pulmonary disease (COPD), and all-respiratory disease (65+ yr) controlling for environmental factors and temporal patterns were investigated. Summary PM(10) effect estimates (percentage change in mean number of daily admissions per 10 microg/m(3) increase) were asthma (0-14 yr) 1.2% (95% CI: 0.2, 2.3), asthma (15-64 yr) 1.1% (0.3, 1.8), and COPD plus asthma and all-respiratory (65+ yr) 1.0% (0.4, 1.5) and 0.9% (0.6, 1.3). The combined estimates for Black Smoke tended to be smaller and less precisely estimated than for PM(10). Variability in the sizes of the PM(10) effect estimates between cities was also investigated. In the 65+ groups PM(10) estimates were positively associated with annual mean concentrations of ozone in the cities. For asthma admissions (0-14 yr) a number of city-specific factors, including smoking prevalence, explained some of their variability. This study confirms that particle concentrations in European cities are positively associated with increased numbers of admissions for respiratory diseases and that some of the variation in PM(10) effect estimates between cities can be explained by city characteristics.
We wanted to assess relations between the daily occurrence of asthma symptoms and fluctuations of air pollution concentrations and meteorological conditions. In a panel of 31 asthmatic patients residing in the town of Piteå in northern Sweden, severe symptoms of shortness of breath, wheeze, cough and phlegm were recorded in an asthma diary together with suspected causes. Sulphur dioxide, nitrogen dioxide, black smoke, relative humidity and temperature were used to evaluate the relationship to the environment. By using multivariate analyses, we found that daily variations in the particulate pollution levels, indicated by black smoke levels below the criteria limits, had significant effects on the risk of developing severe symptoms of shortness of breath. This association was stronger among 10 subjects, who had at least five incident days with severe shortness of breath. Meteorological conditions were not significant in the multivariate models. Cough and phlegm did not show significant relationships to any environmental condition that was evaluated. Only one-third of the subjects reported, at least once during the study, symptoms believed to be related to air pollutants, although we found significant correlations between the pollution levels and the frequency of pollution-related symptoms. We conclude that an association has been established for black smoke as pollutant and shortness of breath as respiratory symptom, and that in certain asthmatics, effects were occurring at lower particulate levels than suggested previously.
Until recently the prevalence of asthma in Sweden was assessed to be 2-3 per cent. An increase in the prevalence of asthma and allergic rhinitis was noted among new conscripts undergoing health work-ups prior to military service with the most marked increase in northern Sweden, were 5 per cent of conscripts were reported to have asthma. In southern Sweden the prevalence remained about 2 per cent. More recent questionnaire studies in mid- and southern Sweden have reported similar rates of respiratory symptoms and use of anti-asthmatic drugs as in northern Sweden, suggesting that there may be no difference in asthma prevalence between the north and the south of the country. The exact prevalence of allergic diseases among Swedish adults is still not clear, but 40 per cent of adults in northern Sweden report that they often have wheezing in the chest, attacks of breathlessness, longstanding cough or sputum production. In questionnaire studies among children about 40 per cent of respondents have reported that they had asthma, allergic rhinitis or other type of hypersensitivity. The absence of generally accepted diagnostic criteria for asthma and allergic disorders in epidemiological studies makes comparison of prevalence difficult. It is thus not possible to be sure that the prevalence of asthma and allergic disorders in Sweden has recently increased. Risk factors for the development of asthma and allergic disorders are under study in Sweden. Several studies report an association in children between urban living and allergic disorders.
Asthma and rhinitis have been related to insomnia. The aim of this study was to further analyse the association between asthma, nasal symptoms and insomnia and to identify risk factors for sleep disturbance among patients with asthma, in a large population-based set of material.
In 2008, a postal questionnaire was sent to a random sample of 45 000 adults in four Swedish cities. The questionnaire included questions on insomnia, asthma, rhinitis, weight, height, tobacco use and physical activity.
Twenty-five thousand six hundred and ten subjects participated. Asthma was defined as either current medication for asthma or at least one attack of asthma during the last 12 months, and 1830 subjects (7.15%) were defined as asthmatics. The prevalence of insomnia symptoms was significantly higher among asthmatics than non-asthmatics (47.3% vs 37.2%,
The theory that cancer may arise under conditions of reduced immune capacity is supported by observations of humans with immune deficiencies such as occur following organ transplants. However, no study on humans has been done in which the reference population was the same as that in which the cancer cases arose and in which there was a sufficiently long period of follow-up. Information on 5,692 Nordic recipients of renal transplants in 1964-1982 was linked with the national cancer registries (1964-1986) and population registries. Person-years at risk were calculated from the date of first transplantation until death or the end of the study period and were multiplied by the appropriate age- and calender-specific incidence rates to obtain the expected numbers of cancers. Standardized incidence ratios (SIR) were calculated after stratification by a number of recorded variables. Altogether, 32,392 person-years were accrued, and 471 cancers occurred, yielding overall SIR of 4.6 (95% CI, 4.0 to 5.2) for males and 4.5 (95% CI, 4.0 to 5.2) for females. Significant overall 2- to 5-fold excess risks in both sexes were seen for cancers of the colon, larynx, lung and bladder, and in men also for cancers of the prostate and testis. Notably high risks, 10-fold to 30-fold above expectation, were associated with cancers of the lip, skin (non-melanoma), kidney and endocrine glands, also with non-Hodgkin's lymphoma, and in women also with cancers of the cervix and vulva-vagina. Among a number of donor and recipient variables studied, including tissue types and compatibility (ABO, HLA, DR), age below 45 years at the time of transplantation was the most important determinant for increased risk at most sites. Kidney transplantation increases the risk of cancer in the short and in the long term, consistent with the theory that an impaired immune system allows carcinogenic factors to act. The tumor risk is small in comparison with the benefits of transplants, but patients should be followed up for signs of cancer.
Comment In: Int J Cancer. 2002 Mar 10;98(2):316-911857425
BACKGROUND: The high and increasing prevalence of childhood asthma is a major public health issue. Various risk factors have been proposed in local studies with different designs. METHODS: We have made a questionnaire study of the prevalence of childhood asthma, potential risk factors and their relations in four regions in Scandinavia (Umeå and Malmö in Sweden, Kuopio in eastern Finland and Oslo, Norway). One urban and one less urbanized area were selected in each region, and a study group of 15962 children aged 6-12 years was recruited. RESULTS: The prevalence of symptoms suggestive of asthma varied considerably between different areas (dry cough 8-19%, asthma attacks 4-8%, physician-diagnosed asthma 4-9%), as did the potential risk factors. Urban residency was generally not a risk factor. However, dry cough was common in the most traffic polluted area. Exposure to some of the risk factors. such as smoking indoors and moisture stains or moulds at home during the first 2 years of life, resulted in an increased risk. However, current exposure was associated with odds ratios less than one. CONCLUSIONS: Our findings were probably due to a combination of early impact and later avoidance of these risk factors. The effects of some risk factors were found to differ significantly between regions. No overall pattern between air pollution and asthma was seen, but air pollution differed less than expected between the areas.
This study aimed to investigate the association between daily air pollution levels and the occurrence of acute respiratory signs and symptoms among people with asthma or asthma-like problems. Thirty eight subjects in the southern Swedish city of Landskrona kept a daily diary for 10 weeks. The daily prevalence of symptoms, supplementary bronchodilator use and peak flow deviations were compared with measurements of environmental nitrogen dioxide (NO2), sulphur dioxide, temperature and humidity in the city. The occurrence of severe asthma, both during the day and during the evening, was significantly positively associated with the concurrent 24 h average concentration of NO2, which never exceeded 72 microg x m(-3). A correlation of borderline significance was found between the use of on-demand medication and the NO2 level. However, peak flow deviations were not associated with air pollution or weather conditions, which may be explained by the beneficial effect of bronchodilators used by 28 of the subjects. The results of this study confirm those of some earlier studies and suggest that aggravation of asthma is related to daily variations in air quality, as indicated by relatively low ambient concentrations of nitrogen dioxide. These results also indicate that it may be appropriate to examine severe asthma symptoms separately.
Asthma is common among adolescents, but there are few population-based studies on the risk factors for incident asthma and wheeze at this age group.
To study risk factors for incident asthma and wheeze in adolescence.
Within the Obstructive Lung Disease In Northern Sweden (OLIN) studies, a cohort of 3430 school children (age 7-8 year) was recruited in 1996. In the present study, this cohort was followed from age 12-19 year. At baseline (age 12 year), 3151 participated and skin prick tests (SPT) were performed. The cohort was resurveyed annually, and risk factors for the cumulative incidence of asthma and wheeze from age 12-19 year were analysed using multivariate Cox regression.
Female sex (wheeze: HR 1.4 95%CI 1.2-1.6; asthma: HR 1.8 95%CI 1.2-2.5) and a positive SPT to cat, dog or horse at baseline (wheeze: HR 1.6 95%CI 1.2-2.1; asthma: HR 2.3 95%CI 1.4-4.0) were significantly associated with the cumulative incidence of wheeze and asthma. Increasing numbers of siblings were inversely related to the incidence of wheeze (HR 0.9 95%CI 0.8-0.97) and asthma (HR 0.8 95%CI 0.7-0.97). Parental asthma was related to the incidence of asthma (HR 1.8 95%CI 1.2-2.6) while ever smoking (HR 2.0 95%CI 1.6-2.4) and house dampness (HR 1.3 95%CI 1.1-1.6) were risk factors for the incidence of wheeze. Maternal ETS exposure increased the risk of incident asthma in non-sensitized subjects (HR 1.9 95%CI 1.0-3.7).
Several environmental risk factors related to the incidence of asthma and wheeze in adolescence were identified and may be possible targets for intervention and prevention.
SETTING: Cross-sectional epidemiological study based on a representative sample of the general population in northern Sweden. OBJECTIVES: To assess the prevalence of respiratory symptoms, the role of respiratory symptoms as indicators of impairment of lung function, and to define risk factors for respiratory symptoms and lung function impairment. DESIGN: The 1340 subjects of 6610 who reported respiratory symptoms suggestive of asthma or chronic bronchitis in a postal questionnaire study were invited to a structured interview and lung function tests. A control group of 315 subjects was also invited. Risk factors were assessed from the postal questionnaire. RESULTS: 400 subjects in the symptomatic group had attacks of breathlessness and wheezing, while none in the control group had them, corresponding to 7% of the original study population. Chronic productive cough was present in 537 subjects, of whom 13 were from the control group, suggesting that 12% of the original study population had this symptom. Persistent wheeze was the symptom that predicted the greatest proportion of cases of impaired lung function. Attacks of breathlessness, wheezing, long-standing cough and sputum production were all related to age, smoking and a family history of asthma. Both chronic productive cough and impaired lung function correlated strongly with smoking and age, and their prevalences differed in different socio-economic groups. CONCLUSION: Impaired lung function can be predicted from respiratory symptoms. Data collected in postal questionnaires suffice for the identification of risk factors. Combinations of symptoms gave greater odds ratios than individual symptoms.
The evaluation of rehabilitation potential is discussed in the context of the recent allocation by the Riksdag of substantial funds for rehabilitation purposes, a measure designed to generate savings to social insurance at least comparable to the allocation. In the article are discussed the difficulties involved in assessing the impact of such political measures, when at the same time the chances of people being able to return to work after extended sick leave are reduced owing to the recession. An evaluation model is presented which, in addition to variables related to monetary savings to the community, incorporates indicators capable of identifying gains due to a rehabilitation programme that are important determinants of the changes of target groups returning to a productive and meaningful life.