Section of Occupational and Environmental Medicine, University of Gothenburg, Box 414, S-405 30 Göteborg, Sweden; Department of Respiratory Medicine and Allergology, Sahlgrenska University Hospital, Göteborg, Sweden.
The aim was to estimate the incidence rate of adult-onset asthma in relation to age, sex, smoking and occupational exposures. A random sample of 18,087 subjects aged 16-75 years was investigated using a respiratory questionnaire. Adult-onset asthma was defined as "physician-diagnosed" asthma with onset at or after 16 years of age. The subjects were asked about year of asthma diagnosis and year of starting and stopping smoking. Subjects with onset of asthma before 16 years of age and physician-diagnosed chronic obstructive pulmonary disease were excluded resulting in a study population of 15,761 subjects. Incidence-rates of adult-onset asthma were calculated and relative risks were assessed using Cox-regression models. During the observation period 1990-2008, 359 new cases of asthma occurred and the cumulative incidence for adult-onset asthma was 2.3%. The crude incidence rate was 1.4/1000 person-years (95% confidence interval 1.3/1000-1.6/1000), with significantly higher incidence rate among women than among men. The incidence rate of asthma during never-smoking years was similar to that during smoking years. The rate of asthma incidence decreased with increasing age. Occupational dust and fume exposure and being female were associated with increased risk of asthma. The attributable fraction for occupational exposure to gas, dust and fumes was 9.4% in the total group, 17.3% among men and 5.1% among women. The incidence rate of asthma was higher among women than among men, and the rate declined with increasing age. A substantial proportion of the new-onset asthma cases could be attributed to occupational exposures.
Despite the well-known association between asthma and rhinitis, in Swedish adults the prevalence of rhinitis rose from 22% to 31% between 1990 and 2008 while asthma prevalence was unchanged. We tested whether the association of rhinitis with asthma was stable over time using the same population-based databases.
Two surveys of adults (20-44 years) living in three regions of Sweden, carried out in 1990 (n = 8982) and 2008 (n = 9156) were compared. Identical questions regarding respiratory symptoms, asthma and rhinitis were used. Asthmatic wheeze: Wheeze with breathlessness apart from colds. Current asthma: Asthma attacks and/or asthma medication use.
Subjects with rhinitis had level time trends in asthmatic wheeze, current asthma and most nocturnal respiratory symptoms between 1990 and 2008, adjusted for age, sex, area and smoking. Any wheeze however decreased slightly. In never-smokers asthma symptoms were similarly associated with rhinitis in 1990 and 2008: any wheeze OR 4.0 vs. 4.4 (p = 0.339); asthmatic wheeze OR 6.0 vs. 5.9 (p = 0.937); and current asthma OR 9.6 vs. 7.7 (p = 0.213). In the whole population there were decreases in the asthma symptoms most closely associated to smoking, which decreased by half 1990-2008. Conversely current asthma, which was strongly associated with rhinitis and not with smoking, increased (p
The purpose of this study was to investigate whether psychosocial stress defined as high strain based on the job demand-control model increases risk for atrial fibrillation.
The present study comprised 6035 men born between 1915 and 1925 and free from previous coronary heart disease, atrial fibrillation and stroke at baseline (1974-1977). Work-related psychosocial stress was measured using a job-exposure matrix for the job demand-control model based on occupation at baseline. The participants were followed from baseline examination until death, hospital discharge or 75 years of age, using the Swedish national register on cause of death and the Swedish hospital discharge register for any registration for atrial fibrillation, resulting in the identification of 436 cases. Data were analysed with Cox regression models with atrial fibrillation as the outcome using high strain as the explanatory variable adjusted for age, smoking, body mass index, hypertension, diabetes and socioeconomic status.
There was an increased risk for atrial fibrillation in relation to high strain (HR 1.32, 95% CI 1.003 to 1.75). When the four categories of the job-strain model were included and low strain was used as reference, the risk for high strain decreased (HR 1.23, 95% CI 0.84 to 1.82).
Exposure to occupational psychosocial stress defined as high strain may be associated with increased risk for atrial fibrillation. The observed increase in risk is small and residual confounding may also be present.
Cites: Int J Cardiol. 2013 Dec 5;170(1):75-8024383072
Cites: Eur Heart J. 2013 Dec;34(47):3624-3123756332
Breathlessness is common in the population, especially in women and associated with adverse health outcomes. Obesity (body mass index (BMI) >30?kg/m2) is rapidly increasing globally and its impact on breathlessness is unclear.
This population-based study aimed primarily to evaluate the association of current BMI and self-reported change in BMI since age 20 with breathlessness (modified Research Council score =1) in the middle-aged population. Secondary aims were to evaluate factors that contribute to breathlessness in obesity, including the interaction with spirometric lung volume and sex.
We included 13?437 individuals; mean age 57.5 years; 52.5% women; mean BMI 26.8 (SD 4.3); mean BMI increase since age 20 was 5.0?kg/m2; and 1283 (9.6%) reported breathlessness. Obesity was strongly associated with increased breathlessness, OR 3.54 (95% CI, 3.03 to 4.13) independent of age, sex, smoking, airflow obstruction, exercise level and the presence of comorbidities. The association between BMI and breathlessness was modified by lung volume; the increase in breathlessness prevalence with higher BMI was steeper for individuals with lower forced vital capacity (FVC). The higher breathlessness prevalence in obese women than men (27.4% vs 12.5%; p
Pneumonia is an important cause of morbidity and mortality. COPD patients using inhaled corticosteroids (ICS) have an increased risk of pneumonia, but less is known about whether ICS treatment in asthma also increases the risk of pneumonia. The aim of this analysis was to examine risk factors for hospitalisations with pneumonia in a general population sample with special emphasis on asthma and the use of ICS in asthmatics.
In 1999 to 2000, 7340 subjects aged 28 to 54?years from three Swedish centres completed a brief health questionnaire. This was linked to information on hospitalisations with pneumonia from 2000 to 2010 and treatment with ICS from 2005 to 2010 held within the Swedish National Patient Register and the Swedish Prescribed Drug Register.
Participants with asthma (n?=?587) were more likely to be hospitalised with pneumonia than participants without asthma (Hazard Ratio (HR 3.35 (1.97-5.02)). Other risk factors for pneumonia were smoking (HR 1.93 (1.22-3.06)), BMI??30?kg/m2 (HR 2.54 (1.39-4.67)). Asthmatics (n?=?586) taking continuous treatment with fluticasone propionate were at an increased risk of being hospitalized with pneumonia (incidence risk ratio (IRR) 7.92 (2.32-27.0) compared to asthmatics that had not used fluticasone propionate, whereas no significant association was found with the use of budesonide (IRR 1.23 (0.36-4.20)).
Having asthma is associated with a three times higher risk of being hospitalised for pneumonia. This analysis also indicates that there are intraclass differences between ICS compounds with respect to pneumonia risk, with an increased risk of pneumonia related to fluticasone propionate.
To study the relation between body mass index (BMI) in young men and risk of early hospitalization with heart failure.
In a prospective cohort study, men from the Swedish Conscript Registry investigated 1968-2005 (n = 1 610 437; mean age, 18.6 years were followed 5-42 years (median, 23.0 years; interquartile range, 15.0-32.0), 5492 first hospitalizations for heart failure occurred (mean age at diagnosis, 46.6 (SD 8.0) years). Compared with men with a body mass index (BMI) of 18.5-20.0 kg/m2, men with a BMI 20.0-22.5 kg/m2 had an hazard ratio (HR) of 1.22 (95% CI, 1.10-1.35), after adjustment for age, year of conscription, comorbidities at baseline, parental education, blood pressure, IQ, muscle strength, and fitness. The risk rose incrementally with increasing BMI such that men with a BMI of 30-35 kg/m2 had an adjusted HR of 6.47 (95% CI, 5.39-7.77) and those with a BMI of =35 kg/m2 had an HR of 9.21 (95% CI, 6.57-12.92). The multiple-adjusted risk of heart failure per 1 unit increase in BMI ranged from 1.06 (95% CI, 1.02-1.11) in heart failure associated with valvular disease to 1.20 (95% CI, 1.18-1.22) for cases associated with coronary heart disease, diabetes, or hypertension.
We found a steeply rising risk of early heart failure detectable already at a normal body weight, increasing nearly 10-fold in the highest weight category. Given the current obesity epidemic, heart failure in the young may increase substantially in the future and physicians need to be aware of this.
Cites: Am J Med. 2008 Nov;121(11):966-73 PMID 18954843
Cites: Eur Heart J. 2015 Jun 7;36(22):1371-6 PMID 25810456
Understanding the reasons for the social gradient in sickness absence might provide an opportunity to reduce the general rates of sickness absence. The complete explanation for this social gradient still remains unclear and there is a need for studies using randomized working population samples. The main aim of the present study was to investigate if self-reported work ability could explain the association between low socioeconomic position and belonging to a sample of new cases of sick-listed employees.
The two study samples consisted of a randomized working population (n = 2,763) and a sample of new cases of sick-listed employees (n = 3,044), 19-64 years old. Both samples were drawn from the same randomized general population. Socioeconomic status was measured with occupational position and physical and mental work ability was measured with two items extracted from the work ability index.
There was an association between lower socioeconomic status and belonging to the sick-listed sample among both women and men. In men the crude Odds ratios increased for each downwards step in socioeconomic status, OR 1.32 (95% CI 0.98-1.78), OR 1.53 (1.05-2.24), OR 2.80 (2.11-3.72), and OR 2.98 (2.27-3.90). Among women this gradient was not as pronounced. Physical work ability constituted the strongest explanatory factor explaining the total association between socioeconomic status and being sick-listed in women. However, among men, the association between skilled non-manual, OR 2.07 (1.54-2.78), and non-skilled manual, OR 2.03 (1.53-2.71) positions in relation to being sick-listed remained. The explanatory effect of mental work ability was small. Surprisingly, even in the sick-listed sample most respondents had high mental and physical work ability.
These results suggest that physical work ability may be an important key in explaining the social gradient in sickness absence, particularly in women. Hence, it is possible that the factors associated with the social gradient in sickness absence may differ, to some extent, between women and men.
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Aims To investigate the association between cardiorespiratory fitness (CRF) and muscle strength in late adolescence and the long-term risk of heart failure (HF). Methods A cohort was created of Swedish men enrolled in compulsory military service between 1968 and 2005 with measurements for CRF and muscle strength ( n?=?1,226,623; mean age 18.3 years). They were followed until 31 December 2014 for HF hospitalization as recorded in the Swedish national inpatient registry. Results During the follow-up period (median (interquartile range) 28.4 (22.0-37.0) years), 7656 cases of first HF hospitalization were observed (mean?±?SD age at diagnosis 50.1?±?7.9 years). CRF and muscle strength were estimated by maximum capacity cycle ergometer testing and strength exercises (knee extension, elbow flexion and hand grip). Inverse dose-response relationships were found between CRF and muscle strength with HF as a primary or contributory diagnosis with an adjusted hazards ratio (95% confidence interval) of 1.60 (1.44-1.77) for low CRF and 1.45 (1.32-1.58) for low muscle strength categories. The associations of incident HF with CRF and muscle strength persisted, regardless of adjustments for the other potential confounders. The highest risk was observed for HF associated with coronary heart disease, diabetes or hypertension. Conclusions In this longitudinal study of young men, we found inverse and mutually independent associations between CRF and muscle strength with risk of hospitalization for HF. If causal, these results may emphasize the importance of the promotion of CRF and muscle strength in younger populations.
Psoriasis is a chronic immune-mediated disease and psoriatic arthritis is a common coexisting condition. Cardiorespiratory fitness is the overall capacity to perform exertion exercise. Low levels of cardiorespiratory fitness are associated with negative health outcomes. Individuals with psoriasis have lower cardiorespiratory fitness compared with individuals without psoriasis. There are no previous studies exploring the association between cardiorespiratory fitness and new-onset psoriasis and psoriatic arthritis.
With the objective to investigate whether low cardiorespiratory fitness in late adolescence increases the risk for onset of psoriasis and psoriatic arthritis, a cohort of Swedish men in compulsory military service between 1968 and 2005 was created using data from the Swedish Military Service Conscription Register. Cardiorespiratory fitness, estimated by maximum capacity cycle ergometer testing at conscription, was divided into three groups: high, medium, and low. Diagnoses were obtained using the Swedish National Patient Register and cohort members were followed from conscription until an event, new-onset psoriasis or psoriatic arthritis, occurred, or at the latest until 31 December 2016. Cox regression models adjusted for confounders at conscription were used to obtain hazard ratios with 95% confidence intervals for incident psoriasis and psoriatic arthritis.
During the follow-up period (median follow-up time 31 years, range 0-48 years), 20,679 cases of incident psoriasis and 6,133 cases of incident psoriatic arthritis were found among 1,228,562 men (mean age at baseline 18.3 years). There was a significant association between low cardiorespiratory fitness and incident psoriasis and psoriatic arthritis (hazard ratio 1.35 (95% confidence interval 1.26-1.44) and 1.44 (95% confidence interval 1.28-1.63), respectively).
These novel findings suggest that low cardiorespiratory fitness at an early age is associated with increased risk of incident psoriasis and psoriatic arthritis among men, and highlight the importance of assessing cardiorespiratory fitness early in life.
Patients with early-onset dementia are a significantly under-recognized subgroup of patients with an increasing prevalence. Epidemiological studies are limited and studies of modifiable risk factors, such as physical fitness, are lacking. We aimed to investigate the associations between cardiovascular fitness individually and in combination with cognitive performance at age 18 and risk of early-onset dementia and mild cognitive impairment later in life. We performed a population-based cohort study of over 1.1 million Swedish, 18-year-old, male conscripts, who underwent conscription exams between 1968 and 2005. These males were then followed for up to 42 years. Objective data on cardiovascular fitness and cognitive performance were collected during conscription exams and were subsequently linked with hospital registries to calculate later risk of early-onset dementia and mild cognitive impairment using Cox proportional hazards models controlling for several confounders. The scores from the exams were divided into tertiles (low, medium, high) for the analyses. The mean follow-up time for the analyses was 25.7 years (standard deviation: 9.3) and the median was 27 years. In total, 30 195 315 person-years of follow-up were included in the study. In fully adjusted models, both low cardiovascular fitness and cognitive performance (compared to high) at age 18 were associated with increased risk for future early-onset dementia (cardiovascular fitness, n = 662 events: hazard ratio 2.49, 95%, confidence interval 1.87-3.32; cognitive performance, n = 657 events: hazard ratio 4.11, 95%, confidence interval 3.19-5.29) and mild cognitive impairment (cardiovascular fitness, n = 213 events: hazard ratio 3.57, 95%, confidence interval 2.23-5.74; cognitive performance, n = 212 events: hazard ratio 3.23, 95%, confidence interval 2.12-4.95). Poor performance on both cardiovascular fitness and cognitive tests was associated with a >7-fold (hazard ratio 7.34, 95%, confidence interval 5.08-10.58) and a >8-fold (hazard ratio 8.44, 95%, confidence interval 4.64-15.37) increased risk of early-onset dementia and early-onset mild cognitive impairment, respectively. In conclusion, lower cardiovascular fitness and cognitive performance in early adulthood were associated with an increased risk of early-onset dementia and mild cognitive impairment later in life, and the greatest risks were observed for individuals with a combination of low cardiovascular fitness and low cognitive performance.