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Introduction: Horse allergens are less studied than allergens from other furry animals and these allergens must be evaluated to understand the complexity of allergy to horses. The aims of this study were to develop assays for the horse allergens Equ c 1 and Equ c 2 in dander and saliva and to determine their levels in ten horse breeds. The study also included a comparison of these findings with previous results on the levels of Equ c 4 performed on the same study population. Method: The study population included 170 horses from 10 horse breeds including American Curly and Russian Bashkir horse, which have been suggested to be hypoallergenic. Competitive ELISA assays were developed, with polyclonal antibodies as capture antibodies, for the detection of Equ c 1 and Equ c 2 in dander and saliva samples. Results: The horse allergens Equ c 1 and Equ c 2 were found in all dander and saliva samples from the ten horse breeds. The GM level (ng/µg protein) of Equ c 1 in dander was 470 (range 129–2,569) and in saliva samples, 40 (range 6–160). The GM level of Equ c 2 in dander was 138 (range 18–1,650) and in saliva samples, 0.8 (range 0.03–17). In dander, there were no significant differences in Equ c 1 and Equ c 2 GM levels between stallions, mares, and geldings. Conclusion: Our results show high intra- and inter-breed variability. Neither the American Curly horse nor the Russian Bashkir horse, earlier categorized as hypoallergenic breeds, was associated with lower allergen levels of Equ c 1, Equ c 2, or Equ c 4 than the other horse breeds investigated.

Background Gender discrimination (GD) and sexual harassment (SH) occur at all academic institutions worldwide. Medical students report high prevalence of GD and SH, which may negatively affect their education and health. There are indications that policies and reforms on reducing GD/SH are insufficient. Swedish medical students’ experiences of GD/SH are monitored by course-evaluations and bi-annual student union evaluations; however, the response rate is usually low. The aim of this study was to compare the exposure to and context of self-reported GD/SH over an 11-year period amongst medical students at a Swedish university. Methods In 2002, a questionnaire (n = 622) was mailed to medical students’ home addresses. It was repeated in 2013 and then distributed during mandatory lectures (n = 856). The questions used a behavioristic approach and asked about specific GH/SH experiences. Participation was voluntary and anonymous. The changes in prevalence over time were calculated by sampling weights in order to obtain comparable estimates, representative of both cohorts. Results The response frequency was 55% (62% women) in 2002 and 81% (59% women) in 2013. The prevalence of GD tended to decrease for male and clinical students in comparison to female and pre-clinical peers. However, the prevalence of SH increased for female compared to male students. The ratio of SH for female pre-clinical students doubled in many instances; most often, the mistreatment occurred in the clinic. Medical doctors were indicated as perpetrators up to five times more often by all students in 2013. Conclusion Our results show a disproportional change in exposure to GD/SH between female and male medical students, resulting in a widening of the gender gap regarding prevalence of GD and SH between 2002 and 2013. In particular, personal experiences of SH increased for both sexes. It is proof that institutional efforts to fight mistreatment might be ineffective.

Aim The study describes what helps nurse managers maintain the strength to keep going as leaders. Background Good leadership is important for the quality of patient care, patient satisfaction in care and efficiency. Many nurse managers stay on despite challenges at work. Methods Twelve nurse managers were interviewed. Data were analysed by systematic text condensation according to Malterud. Results The results were as follows: A—Walking side by side with my employees; B—Knowing that I mean something to my employees; C—Talking to myself—asking myself tough questions; D—Having someone to talk to, to decrease the feeling of being alone; E—Leading and managing in my own way—the fear of not succeeding is my motivation. Conclusion The nurse managers built their own strategies to get through and get on when difficult situations arose. In order to succeed in leading their employees, the nurse managers gathered their inner strength through moving caritatively back and forth between the ‘secret room’ and the ‘staff room’ in the house of leadership. Implications in Nursing Management The manuscript gives insights into where nurse managers found sources of strengths in their everyday work. To realize their employees’ strengths and motivation made a difference for nurse managers as a driving force. By having someone to talk to and by asking themselves tough questions, they were prepared for the challenges that came. Paid Open Access

Summary Background Horses are an important source of allergens, but the distribution of horse allergens is poorly understood. Five horse allergens have been identified, Equ c 1‐4 and 6. Equ c 4 seems to be an important allergen, with an IgE‐binding frequency of 77% in horse‐sensitized individuals. Objectives The aim of this study was to investigate levels of horse allergen Equ c 4 in dander, saliva and urine from ten horse breeds. Method The study population included 170 horses (87 mares, 27 stallions, 56 geldings) from ten breeds. Horse dander, saliva and urine samples were collected. Levels of horse allergen Equ c 4 were quantified using a two‐site sandwich ELISA (mAb 103 and 14G4) and were expressed as Equ c 4 U/μg protein. Results The horse allergen Equ c 4 was present in all dander and saliva samples from ten horse breeds, with high within‐breed and inter‐breed variations; GM values were 639 Equ c 4 U/μg protein (range 5‐15 264) for dander and 39.5 (4‐263) for saliva. Equ c 4 was found in 19/21 urine samples. Adjusted for age, sex and changes over time, no differences between breeds could be seen in dander, while in saliva the North Swedish horse showed lower levels of Equ c 4 than any other breed. The levels of Equ c 4 protein in dander and saliva were significantly higher in samples from stallions compared to mares and geldings, independent of breed. Conclusions and Clinical Relevance The results show a high variability in allergen levels of Equ c 4 in dander and saliva both within and between breeds. Significantly higher levels were found in stallions compared to mares and geldings, independent of breed. Results suggest that none of the horse breeds studied can be recommended for individuals allergic to Equ c 4.

Purpose To investigate why nurse anesthetists and operating room nurses choose to stay in the same workplace. Design Qualitative design. Methods Individual interviews were conducted with 15 nurse specialists from four hospitals in Sweden. Two men and 13 women aged between 43 and 63 participated. Data were analyzed with systematic text condensation according to Malterud. Findings Three themes were identified. (1) Organizational stability contributed to low staff turnover, with good spirits between colleagues, representing everyone's equal value and resulting in a feeling of homelikeness. (2) Sustained development in one's own profession. (3) A humane head nurse who was at hand, who was a facilitator, who knew staff members, and eliminated obstacles for them. Conclusions In a nonhierarchical and stable organization with a head nurse with caritative leadership skills, a welcoming working environment with opportunities for professional development is created. Thus, nurse specialists choose to stay, contributing to organizational development.

Introduction Occupational lung diseases are a broad group of diagnoses caused by a wide range of hazards in the workplace such dusts, chemicals or proteins. The International Labour Organisation estimates that 700.000 people in the world die yearly from occupational lung diseases. Teaching the subject at the undergraduate levels in medical schools is important, so that the students consider these diagnoses later on in their careers. However, earlier surveys have shown that the interest in occupational medicine is low in medical students. Teaching occupational lung diseases can be especially challenging since the terminology is confusing. Methods In order to improve students’ learning, a puzzle game on occupational lung diseases was developed. On a game-board, five columns and ten rows made a grid of fifty squares. The headings of the five columns were different disease groups: Pneumoconiosis, Inhalation Fevers, Allergic Alveolitis, Occupational Asthma, and Toxic Pneumonitis. The rows headings were: Subtypes, Prevalence, Exposure, Symptoms, Clinical Findings, Lab Tests, Chest X-ray, Pulmonary Function Tests, Prognosis, and Treatment. Fifty cards with text descriptions should be placed on the correct square on the board. For example, one card described that more than 350 substances (Exposure) have been associated with occupational asthma. After finding the correct place for all the cards, they are turned upside down showing a poster from a movie related to occupational medicine for example Norma Ray. The students are asked to describe that relation. Results The game has been tested by 160 medical students who were very interested and worked intensely. The students gave high ratings in the course evaluation and enjoyed the puzzle. Conclusion This educational game on occupational lung disease probably improved medical students’ learning outcomes compared to passively listening to lectures. The game is also suitable for other groups such as physicians and staff in Occupational Health Services.

Organic dust toxic syndrome (ODTS) is an acute, febrile, noninfectious, flu-like, short-term reaction that can be seen in a range of situations after inhalation of substances that give rise to an inflammatory reaction in the lungs. There are anecdotical reports suggesting that ODTS is a risk factor for asthma in farmers. In a cross-sectional study, questionnaires were mailed to farmers in middle Sweden and southern Sweden. Sixty percent of the farmers (1004 men and 129 women) responded to the questionnaire. The mean age was 51 years. Nine percent were smokers and 24 percent ex-smokers. The female farmers had a significantly higher prevalence of doctor-diagnosed asthma compared to the males, 8.3 percent compared to 4.5 percent (p

The lack of specialist nurses in operating theatres is a serious problem. The aim of this study was to describe reasons why specialist nurses in perioperative care chose to leave their workplaces and to describe the process from the thought to the decision. Twenty specialist nurses (i.e. anaesthesia, NA, and operating room nurses) from seven university- and county hospitals in Sweden participated in qualitative individual in-depth interviews. Data were analysed by systematic text condensation. We identified four themes of reasons why specialist nurses quitted their jobs: the head nurses' betrayal and dismissive attitude, and not feeling needed; inhumane working conditions leading to the negative health effects; not being free to decide about one's life and family life being more important than work; and, colleagues' diminishing behaviour. Leaving one's job was described as a process and specialist nurses had thought about it for some time. Two main reasons were described; the head nurse manager's dismissive attitude and treatment of their employees and colleagues' mistreatment and colleagues' diminishing behaviour. Increasing knowledge on the role of the head nurse managers in specialist nurses' decision making for leaving their workplace, and creating a friendly, non-violent workplace, may give the opportunity for them to take action before it is too late.

Introduction: Wood pellets are used as a source of renewable energy for heating purposes. Common exposures are wood dust and monoterpenes, which are known to be hazardous for the airways. The purpose of this study was to study the effect of occupational exposure on respiratory health in wood pellet workers. Materials and methods: Thirty-nine men working with wood pellet production at six plants were investigated with a questionnaire, medical examination, allergy screening, spirometry, and nasal peak expiratory flow (nasal PEF). Exposure to wood dust and monoterpenes was measured. Results: The wood pellet workers reported a higher frequency of nasal symptoms, dry cough, and asthma medication compared to controls from the general population. There were no differences in nasal PEF between work and leisure time. A lower lung function than expected (vital capacity [VC], 95%; forced vital capacity in 1 second [FEV1], 96% of predicted) was noted, but no changes were noted during shifts. There was no correlation between lung function and years working in pellet production. Personal measurements of wood dust at work showed high concentrations (0.16–19 mg/m3), and exposure peaks when performing certain work tasks. Levels of monoterpenes were low (0.64–28 mg/m3). There was no association between exposure and acute lung function effects. Conclusions: In this study of wood pellet workers, high levels of wood dust were observed, and that may have influenced the airways negatively as the study group reported upper airway symptoms and dry cough more frequently than expected. The wood pellet workers had both a lower VC and FEV1 than expected. No cross-shift changes were found.

SummaryPsychological factors such as anxiety and depression are prevalent in patients with asthma. The purpose of this study was to investigate the relationship between respiratory symptoms and psychological status and to estimate the importance of psychological status in comparison with other factors that are known to be associated with respiratory symptoms.This study included 2270 subjects aged 20–44 (52% female) from Sweden, Iceland, and Norway. Each participant underwent a clinical interview including questions on respiratory symptoms. Spirometry and methacholine challenge were performed. Symptoms of depression and anxiety were measured using the Hospital Anxiety and Depression Scale (HADS).Eighty-two percent of the subjects reported no anxiety or depression whatsoever, 11% reported anxiety, 2.5% depression and 4% reported both anxiety and depression. All respiratory symptoms, such as wheezing, breathlessness and nightly symptoms, were more common, at a statistically significant level, in participants who had depression and anxiety, even after adjusting for confounders (ORs 1.33–1.94). The HADS score was the most important determinant for nightly symptoms and attacks of breathlessness when at rest whereas bronchial responsiveness was the most important determinant for wheezing, and breathlessness when wheezing. The probability of respiratory symptoms related to HADS score increased with increasing HADS score for all respiratory symptoms.In conclusion, there is a strong association between respiratory symptoms and psychological status. There is therefore a need for interventional studies designed to improve depression and anxiety in patients with respiratory symptoms.

Respiratory disease is a major occupational hazard in farming. The purpose of this study was to investigate determinants of asthma and other respiratory symptoms in farmers. Questionnaires were mailed to all farms in the county of Uppsala and in northwestern part of the county of Skane. The questionnaire contained questions on respiratory symptoms and on the work and production on the farms. Sixty percent of the farmers responded to the questionnaire. Only farmer working at least 15 hours a week with half of their time in farming (1515 men and 206 women) were included in the analysis. The mean age was 51 years. Nine percent were smokers and 24 percent ex-smokers. The female farmers worked significantly more often in all productions involving animals. They had a significantly higher prevalence of doctor-diagnosed asthma and chronic bronchitis compared to the males, 7.5 percent vs. 4.3 percent (p

Traditionally, clinical outcomes such as spirometry are used to assess the progress of asthma and the effectiveness of treatment but the patients9 perception of their health-related quality of life (HRQL) has also become an important aspect. We have earlier shown that subjective assessments of HRQL was a predictors of mortality and survival in an 18 year follow-up of elderly, but this association was not found when analyzing the asthmatic group alone. In this analysis including a follow-up time of 24 years, we want to investigate whether low HRQL is a predictor of mortality in asthmatics. In 1990, a cohort was investigated using a respiratory questionnaire. To assess HRQL, the generic instrument Gothenburg Quality of Life (GQL) was used. The participants, aged 60-69 years in 1990, were also investigated by spirometry and allergy testing. There were 223 subjects with clinically verified asthma, 148 subjects with respiratory symptoms but no asthma or other lung diseases, and 102 subjects with no respiratory symptoms. Mortality in the cohort was followed during the follow-up period 1990-2013. Altogether, 306 of the 472 subjects in the original cohort had died. Mortality was significantly higher in men, in older subjects, in smokers and subjects with a low FEV1 but not in subjects with a positive allergy test. A higher symptoms score for GQL was significantly related to increased mortality. There was no difference in mortality between the asthmatic and the non-asthmatic groups. The prognostic implications of a low HRQL in the whole group and the fact that the asthmatic group had a lower HRQL than the other group9s supports the use of HRQL instruments in clinical health assessments.

Respiratory disease is a well known health hazard for farmers, but the long-term prognosis is less well known. This is a 12-year follow-up of an investigation of Swedish farmers, most of them dairy farmers. A questionnaire was mailed to all 418 farmers who were alive of the farmers originally participating in 1982. They were invited to an interview, spirometry, and blood sampling. Ninety-one per cent (380) of the farmers, 321 men and 59 women, responded to the questionnaire. The mean age was 56 years for the men and 55 years for the women. Of the group, 10% were smokers, 25% ex-smokers, and 65% had never smoked. The population estimate for asthma in the farmers was 8.9% in 1994 compared to 2% in 1982, and to 5.4%-6.6% in the general population in the region in 1982. Of the asthmatic subjects, one-third had positive RAST tests (radioallergosorbent tests). Almost 90% of the new onset asthma cases since 1982 had non-IgE-mediated asthma. Most of the IgE-mediated asthmatics had had symptoms for many years, while 70% of the non-IgE-mediated asthmatic farmers had no or only wheezing with colds 1982. Two new cases of hypersensitivity pneumonitis were identified, and 7.3% had experienced inhalation fever during the last 12 years. In general, individuals with asthma and chronic bronchitis who had left farming were in better health in 1994 as compared to 1982. In conclusion, farmers have an enhanced risk to develop asthma increasing with age. Asthma in farmers is often non-IgE-mediated.

Asthma is a common chronic health condition among the elderly and an important cause of morbidity and mortality. Some studies show that subjective assessments of health-related quality of life (HRQL) are important predictors of mortality and survival. The primary aim of this study was to investigate whether low HRQL was a predictor of mortality in elderly subjects and whether such an association differed between subjects with and without asthma.In 1990, a cohort in middle Sweden was investigated using a respiratory questionnaire. To assess HRQL, the generic instrument Gothenburg Quality of Life (GQL) was used. The participants were also investigated by spirometry and allergy testing. The present study was limited to the subjects in the oldest age group, aged 60-69 years in 1990, and included 222 subjects with clinically verified asthma, 148 subjects with respiratory symptoms but no asthma or other lung diseases, and 102 subjects with no respiratory symptoms. Mortality in the cohort was followed during 1990-2008.Altogether, 166 of the 472 subjects in the original cohort had died during the follow-up period of 1990-2008. Mortality was significantly higher in men, in older subjects, in smokers, and subjects with a low forced expiratory volume in one second (FEV(1)). There was, however, no difference in mortality between the asthmatic and the nonasthmatic groups. A higher symptoms score for GQL was significantly related to increased mortality. No association between HRQL and mortality was found when limiting the analysis to the asthmatic group, although the asthmatics had a lower symptom score for GQL compared to the other groups.A higher symptom score in the GQL instrument was significantly related to increased mortality, but this association was not found when analyzing the asthmatic group alone. The negative prognostic implications of a low HRQL in the whole group and the fact that the asthmatic group had a lower HRQL than the other group supports the use of HRQL instruments in clinical health assessments.

The causes of the worldwide increase in asthma seen during the last decades remain largely unexplained, but lifestyle and diet are suggested to play important roles. In this follow up of a large-scale population sample in Sweden, we wanted to identify modifiable risk factors for the cumulative incidence over a 13-year follow-up period. In 1990, a self-administered questionnaire was completed by 12,560 individuals from three age groups (16, 30-39 and 60-69 years of age) in two counties of Sweden. In 2003, the eligible subjects (n = 11,282) were sent a new postal questionnaire. In total 8150 (response rate 73%) answered the questionnaire. The prevalence of asthma in 2003 had increased in all ages. In the young adults, the asthma prevalence rose from 11.3% in 1990 to 25.0% in 2003. Adult asthma onset was identified in 791 of the participants. Smoking [RR (95% CI) = 1.37 (1.12-1.68)], BMI [1.49 (1.25-1.77 per inter quartile range)], and nocturnal gastro-oesophageal reflux (GOR) [2.16 (1.72-2.72)] were significant independent risk factors for the cumulative incidence of asthma. The impact of risk factors differed between the age groups where BMI and GOR had a significantly higher impact in the middle aged and the elderly (p < 0.05). High consumption of fruit and fish was protective especially in the elderly [0.52 (0.35-0.77)]. No significant difference was found in the impact of risk factors between men and women. Weight loss, smoking cessation and a diet rich in fruit and fish may be of importance in preventing onset of adult asthma.

Different instruments have been developed to assess health-related quality of life (HRQL) in asthma patients. However, relatively few studies have assessed HRQL in asthma patients from a general population, and it is still unclear which instrument is most suitable. The purpose of this study was to compare HRQL in clinically verified asthmatics with subjects with respiratory symptoms without asthma and with subjects with no respiratory symptoms from a general population. The generic instrument Gothenburg Quality of Life (GQL) was used. A secondary aim was to study if GQL had any prognostic value in asthma.A cohort of three age groups in Sweden was investigated in 1990 using a respiratory questionnaire and GQL. The cohort consisted of 616 subjects with asthma, 488 subjects with respiratory symptoms but no asthma, and 347 subjects without respiratory symptoms. The participants were also investigated by spirometry and allergy testing. In a follow-up study, subjects were identified who had persistent and improved asthma.The prevalence of 28 of the 30 common symptoms in GQL was significantly increased (p0.001) in subjects with asthma as compared to non-asthmatics. All symptoms in the domains heart and lung, head, musculoskeletal, tension, and depression were significantly increased among the asthmatics. The asthmatics also rated their physical well-being lower (p0.001) than subjects with no respiratory symptoms. Subjects with persistent asthma had a significantly higher prevalence of 7 of the 30 symptoms and lower social well-being than subjects showing improvement in asthma during the follow-up. All differences remained significant after adjusting for age, sex, and smoking habits.Subjects with asthma had different symptom-profiles compared to those of non-asthmatics, with a higher prevalence of both respiratory and non-respiratory symptoms. Asthma is also a disease that is related to low well-being. The use of quality-of-life questionnaires such as the GQL may provide useful information for evaluating the non-respiratory aspects of asthma as well as for assessing the impact of disease on health status and well-being.

Asthma is one of the most common chronic illnesses and affects health in many ways with reduced health related quality of life (HRQL) as a result. In a recent study, we found that there is a strong association between respiratory symptoms and psychological status (anxiety and depression). The aim of this study was to investigate associations between psychological status and HRQL in asthmatics. This study included 2270 subjects aged 20–44 (52% females) from Sweden, Iceland, and Norway. Each participant underwent a clinical interview including questions on respiratory symptoms. Symptoms of depression and anxiety were measured using the Hospital Anxiety and Depression Scale (HADS). Health related quality of life was measured with the 36-Item Short Form Health Survey (SF-36). The physical (PCS) and mental health (MCS) component scores were calculated with higher values indicating better health status. An asthma score consisting of a simple sum of the positive answers to five respiratory symptoms was used in the analysis i.e. the score ranges from 0 to 5. The HADS was a strong determinant for both PCS and MCS with increasing HADS being associated with decreased PCS and MCS after adjustment for possible confounding variables. An interaction between HADS and the asthma symptom score was observed for PCS, with associations being more pronounced for individuals with more symptoms than for individuals without symptoms.

Objectives This study investigated the possibility of pleuropulmonary lesions, which can occur as rare but serious side effects of different ergot drugs, occurring more commonly in persons earlier exposed to asbestos. Methods All reports of pleuropulmonary side effects of the ergot drugs used in Sweden in the Swedish side effect registry from 1985 to 2003 were studied. In addition, the literature was reviewed. Results In the registry, 47 men and 3 women were found. Of the men, 24 were exposed to asbestos, and 2 denied such exposure; 2 of the 3 women were exposed. In the literature, 111 patients were found—32 had confirmed exposure and 15 denied it. For most of the patients, it was not possible to determine exposure. Conclusions Enough evidence exists to postulate that earlier asbestos exposure in combination with the intake of ergot drugs can cause pleuropulmonary lesions.

Bromocriptine, which is used in the treatment of Parkinson's disease, can cause adverse pleuropulmonary reactions. Exposure to asbestos can result in similar lesions. Fifteen patients with former exposure to asbestos, who developed pleural fibrosis after treatment with bromocriptine, were observed independently in Sweden (11 patients) and Australia (four patients). The patients complained of malaise, often associated with weight loss, dyspnoea, and a disturbing cough. Laboratory values included increased erythrocyte sedimentation rate and a low haemoglobin level. Lung function tests showed a restrictive lung function defect. Chest radiographs showed bilateral pleural fibrosis, with small amounts of fluid in some cases. Soon after bromocriptine was withdrawn, the patients improved clinically, and the laboratory values returned to normal. However, in most cases, pleural fibrosis and a restrictive lung function defect persisted to some extent. In conclusion, in patients who develop pleuropulmonary fibrosis whilst being treated with bromocriptine, former exposure to asbestos should be investigated. Conversely, when pleural changes develop in a patient on bromocriptine and with prior exposure to asbestos, the possible causative role of the drug should be discussed. Special follow-up may be indicated when bromocriptine is planned in a patient with previous asbestos exposure, and if symptoms or signs of pleural fibrosis develop, bromocriptine withdrawal should be considered.

Introduction Our knowledge about atopy as a longitudinal predictor of asthma is limited. The purpose of this study was to investigate the prognosis of asthma and risk factors for asthma onset, especially sensitization of specific allergens in a population sample. Material and methods A cohort responded to a respiratory questionnaire in 1990 and 2003. At baseline, 2,060 subjects who, in the screening questionnaire, reported respiratory symptoms and 482 controls were investigated with interviews, spirometry, and skin-prick test. A total of 721 asthmatics and 976 subjects without respiratory disease were clinically verified. At follow-up in 2003, 340 subjects with persistent asthma and 186 subjects with asthma remission were identified, while 76 subjects reported new asthma onset. Results Sensitization to pets and a high symptom score were significant determinants of persistent asthma (odds ratio (OR) 3.2 (95% CI 1.9–5.6) and 5.7 (2.5–13.3), respectively) and onset of asthma (OR 2.6 (1.1–6.0), and 1.7 (1.2–2.3)). A high self-reported responsiveness to airway irritants (OR 1.6 (1.1–2.2)), and more asthma medications (OR 2.0 (1.3–2.9)) were additional indicators of persistent asthma at the follow-up. Belonging to the older age group decreased the risk both of having persistent asthma and asthma onset. Discussion Asthmatics sensitized to pets have a more severe outcome than asthmatics not sensitized to pets. Sensitization to pets was also a strong predictor for onset of asthma. Special attention should be given to asthmatics who report having severe symptoms and problems with airway irritants as such patients are more likely to have persistent problems.

People with asthma suffer from impaired health-related quality of life (HRQL), but the determinants of HRQL among asthmatics are not completely understood. The aim of this investigation was to study determinants of low HRQL in asthmatics and to study whether the determinants of HRQL differ between sexes and age groups. A cohort of three age groups in Sweden was investigated in 1990 using a questionnaire with focus on respiratory symptoms. To study quality of life, the generic instrument Gothenburg Quality of Life was used. The participants were also investigated with interviews, spirometry, and allergy testing. Asthma was diagnosed in 616 subjects. Fifty-eight per cent (n = 359) of the subjects were women; and 24% were smokers, 22% ex-smokers, and 54% were non-smokers. Women were more likely than men to report poor health-related quality of life. Respiratory symptoms severity was another independent determinant of a lower quality of life as well as airway responsiveness to irritants. Current and former smokers also reported lower quality of life. Finally, absenteeism from school and work was associated with lower quality of life. Factors such as sex, smoking habits, airway responsiveness to irritants, respiratory symptom severity, allergy, and absenteeism from school and work were associated with low HRQL in asthmatics.

The aim of this thesis was to identify risk factors for the onset of adult asthma. Other objectives were to study determinants of smoking habits and the association between sensitization and outcome of asthma. In 1990, a questionnaire was distributed to 12,732 individuals from three age groups (16, 30-39 and 60-69 years) in two counties of Sweden. In a second phase, 2538 subjects who had reported respiratory symptoms and 600 controls were invited to clinical investigations, 81% participated. At the follow-up in 2003 subjects of the remaining cohort (11,282) were re-invited. Analyses are based on the 67% (n=7563) who responded to both questionnaires 1990 and 2003. In 2003, 17.2% of the young adults, 11.4% of the middle-aged and 10.3% of the elderly reported having, or having had, asthma. A total of 791 subjects reported onset of asthma during the 13-year study period. Lifestyle factors such as smoking, obesity, hard physical training and a low consumption of fruit and fish were constant risk factors for onset of asthma after adjusting for socioeconomic group. A smoker’s risk of asthma onset was increased by 37%. The impact of risk factors differed between the age-groups. BMI had a significantly higher impact in the middle-aged and elderly. In subjects participating in the clinical investigations in 1990, sensitization to pets, were determinants of both persistent asthma and onset of asthma in 2003. The risk for persistent asthma was threefold. The risk for onset of asthma was more than doubled. Smoking at baseline in 1990 was the strongest determinant of being a smoker in 2003. Allergic sensitization and clinically verified asthma were not associated with smoking habits in 2003. No differences in changing smoking habits could be identified between smokers with or without asthma. In conclusion, modifiable lifestyle factors are important risk factors for adult onset asthma. The co-occurrence and interplay between asthma and cigarette smoking is still puzzling.

The causes of the worldwide increase in asthma seen during the last decades remain largely unexplained, but lifestyle and diet are suggested to play important roles. In this follow up of a large-scale population sample in Sweden, we wanted to identify modifiable risk factors for the cumulative incidence over a 13-year follow-up period. In 1990, a self-administered questionnaire was completed by 12,560 individuals from three age groups (16, 30-39 and 60-69 years of age) in two counties of Sweden. In 2003, the eligible subjects (n = 11,282) were sent a new postal questionnaire. In total 8150 (response rate 73%) answered the questionnaire. The prevalence of asthma in 2003 had increased in all ages. In the young adults, the asthma prevalence rose from 11.3% in 1990 to 25.0% in 2003. Adult asthma onset was identified in 791 of the participants. Smoking [RR (95% CI) = 1.37 (1.12-1.68)], BMI [1.49 (1.25-1.77 per inter quartile range)], and nocturnal gastro-oesophageal reflux (GOR) [2.16 (1.72-2.72)] were significant independent risk factors for the cumulative incidence of asthma. The impact of risk factors differed between the age groups where BMI and GOR had a significantly higher impact in the middle aged and the elderly (p0.05). High consumption of fruit and fish was protective especially in the elderly [0.52 (0.35-0.77)]. No significant difference was found in the impact of risk factors between men and women. Weight loss, smoking cessation and a diet rich in fruit and fish may be of importance in preventing onset of adult asthma.

Mold dust exposure in the trimming departments of sawmills may cause inhalation fever as well as allergic alveolitis. Responses to questionnaires sent to 2,052 workers from trimming departments of 233 Swedish sawmills showed that one of five workers experienced work-related febrile attacks. A single case of allergic alveolitis was found.

Study objective: To compare exposure to microorganisms associated with allergic alveolitis (AA) and with febrile reactions to inhaled mold dust (organic dust toxic syndrome [ODTS]) in farmers and in normal subjects. Design A prospective study in which exposure was evaluated within two weeks of medical consultation for AA or ODTS. Samples were collected during normal farming (background) and during the handling of materials associated with disease or causing maximal exposure in reference farms (worst case). Setting: Swedish farms Participants: Eleven farmers with a confirmed diagnosis of AA from ten farms, 16 subjects with symptoms of ODTS from 12 farms, and 17 reference farmers. Measurements and results: Worst-case samples representative of the exposure preceding disease were obtained on four farms where five farmers had had AA; the samples contained on average 2.6 ± 1.8 × 109 (SD) spores/m3 of air. On six farms where nine farmers had had ODTS, representative samples averaged 13 ± 13 × 109 spores/m3, and on reference farms this figure was 0.12 ± 0.20 × 109 spores/m3. The daily spore dose associated with allergic alveolitis was 2 × 109 spores/d, which was ten times higher than on reference farms. The average dose associated with ODTS was 2 × 1010 spores. Worst-case samples, collected during 10 to 30 min, contributed to more than 90 percent of the day exposure on farms where AA or ODTS had occurred. Conclusion: Allergic alveolitis was associated with high exposure levels on most weekdays for weeks, and ODTS was associated with extreme exposure occurring on a single day. There was no correlation with individual spore types and disease and the present results are compatible with a hypothesis that common cell wall components of microorganisms may cause "toxic" symptoms and stimulate immune reactions.

The incidence of allergic alveolitis (AA) and of febrile reactions (FR) to inhaled mold dust in those who did not meet the criteria of AA was investigated in Swedish farmers, and the findings were related to farming methods and exposure type. A questionnaire was completed by 6,702 farmers. A stratified sample of 390 farmers underwent examination comprising spirometry, a skin-prick test, blood tests for precipitating antibodies and total IgE and an interview concerning symptoms, exposure and farming methods. The yearly incidence of AA was 2–3/10,000 farmers. The incidence of FR was 30–50 times higher (1/100 farmers) and the majority of these reactions was of a toxic rather than allergic type (organic dust toxic syndrome). Among farmers with recent FR or AA there was a higher frequency of positive precipitin reactions (p < 0.05). Exposures to moldy grain, straw, wood chips and hay were associated with both AA and FR. A major difference in exposure between 17 farmers with AA and 80 with FR was that AA appeared to require repeated exposure, while FR was associated with occasional heavy exposure to mold dust.

A questionnaire was sent to 512 farmers, members of a local farmer's health association. Eighty were interviewed, and their serum precipitins and total serum immunoglobulin E (IgE) values were determined. Forty-five underwent extensive pulmonary function tests. On the basis of the clinical evaluation it was estimated that 19% of the farmers had experienced febrile reactions (fever and/or shivering) following exposure to organic dust, 50% of the 19% having been exposed within the last 2.5 years. Common causes were moldy grain, hay, and woodchips. The pulmonary function, gas exchange, and chest radiographs of those who had previously had febrile reactions were normal. Only 13% showed positive precipitin reactions in Ouchterlony double-diffusion tests. With more sensitive tests, positive precipitins were found in 59%, but they were negatively correlated with febrile episodes. Air samples collected during work with hay and grain on 21 farms contained between 10(7) to 2 X 10(9) microorganisms/m3. The highest values were associated with symptoms of alveolitis. Eleven percent of the farmers reported obstructive chest symptoms following exposure to organic dust. This group showed decreased pulmonary function and elevated serum IgE levels and included a high proportion of smokers and exsmokers. No correlation was found between febrile and obstructive reactions.

The endotoxin concentration in air was measured in farms where 11 farmers had experienced febrile reactions or allergic alveolitis and in a random sample of farms with 17 symptomless farmers. Samples were obtained during normal dairy farming in eight reference farms (background samples) and in all farms during the handling of material which had probably caused symptoms or disease or, in reference farms, maximal spore exposure (worst case samples). In addition, parallel samplers were used in reference farms, one with a cyclone (5 microns cutoff) and one without, to measure the dust and endotoxin concentrations in the respirable fraction and total dust. The endotoxin worst case values varied from less than 0.01 to greater than 50 micrograms/m3 in symptom farms (median 6.4 micrograms/m3, geometric mean 2.2 micrograms/m3) and from less than 0.01 to greater than 50 micrograms/m3 in reference farms (median 42 micrograms/m3, geometric mean 29 micrograms/m3). This difference was not statistically significant. The background values in reference farms were 1.3 (median) and 0.4 (geometric mean) micrograms/m3. The differences between samples with and without cyclone and between background and worst case samples were statistically significant (p less than 0.02). About 75% of the activity was found in the non-respirable fraction. No correlation was found between exposure to endotoxin and symptoms in farmers. There were weak, but statistically significant, correlations between endotoxin concentrations and total spore count or dust concentrations. The surprisingly high endotoxin values in the respirable fraction of air from environments which apparently did not cause symptoms raises the concern that the Limulus amebocyte assay might be sensitive to other components in the dust rather than endotoxin.

SummaryBackgroundHealth-related quality of life (HRQL) has been increasingly used as an outcome measure in asthma, but less is known about the prognostic implication of low health-related quality of life. The purpose of this study was to investigate if a set of quality of life measures could predict onset of asthma.MethodsIn the baseline study 391 subjects without asthma answered a respiratory questionnaire and the Gothenburg Quality of Life (GQL) instrument in 1990. The GQL questionnaire included two parts: (1) the prevalence of HRQL-related symptoms and (2) well-being scores for physical, mental and social dimensions. The participants were also investigated with spirometry and allergy testing. In 2003, the same respiratory questionnaire that had been used in 1990 was sent. There were 290 responders, of whom 22 subjects had developed asthma.ResultsParticipants who had developed asthma by the follow-up had a higher prevalence of sleep disturbances (30% vs. 10%), problems with chest pain (16% vs. 2%), depression (40% vs. 20%) difficulty relaxing (40% vs. 13%) and constipation (25% vs. 2%) at baseline than participants who did not develop asthma (p

Allergic alveolitis due to mold dust inhalation in farmers is a severe but rare disease in Scandinavia. In this report 38 cases of the disease are presented. There were 31 men and 7 women, with mean ages of 46 and 38 years respectively. Strict diagnostic criteria were used, resulting in 21 definite, 12 probable and 5 possible cases. None of the patients were current smokers, but 10 of the men were ex-smokers. The great majority of the patients fell ill between October and April. The symptoms were dyspnea, cough, fatigue, episodes of fever, and in some cases loss of weight. The average duration of the disease was 6 months. The moldy material most commonly associated with the disease was straw, followed by hay, grain, and wood chips. For those tested serum lactate dehydrogenase was raised in 80% and the mean value for PaO2 was 7.8 kPa. Precipitating antibodies to mold antigens were positive in 68%. In general, pulmonary function tests showed a restrictive pattern. Over half of the patients still had dyspnea on exercise after recovery. Three fourths of the patients were treated with antibiotics and thus clearly had been misjudged as having an infection.

Clinical symptoms and exposure conditions were investigated in 80 farmers with organic dust toxic syndrome, defined as the occurrence of febrile reactions after exposure to organic dust in subjects with no evidence of allergic alveolitis. The material was compiled from a field study of febrile reactions in the farming community and the diagnosis was based on interviews performed by physicians. Of the 75 men (mean age 44) and five women (mean age 39), only 13% of the men and none of the women were current smokers. One attack had been experienced by 44% and the remaining subjects had had two or more attacks, often several years apart. The duration of symptoms was 24 hours or less in 46% of the farmers and in 95% of the cases the symptoms lasted less than one week. The attacks were most common in the autumn and were usually provoked by handling grain (80% of the farmers with organic dust toxic syndrome). Other causes were hay, straw, wood chips, and silocapping material. The material was usually described as extremely mouldy and the episodes were usually provoked by unusual work tasks such as cleaning grain bins or removing mouldy feed. Twenty three farmers had consulted physicians: five of nine examined during symptoms had slightly abnormal chest radiographs and two of four examined had decreased arterial oxygen tension. Spirometry performed during a symptom free interval was normal.