The risk of asthma in relation to occupational exposures: a case-control study from a Swedish city.
(41/7400)
The purpose of this study was to estimate the risk of adult asthma in relation to certain occupational exposures. The study was designed as a case-control study in Goteborg, including 321 subjects with asthma, born between 1926 and 1970. Controls (n=1,459) were randomly selected from the same area from registers of the 1986 population. Questionnaire information was collected in 1996, and included occupational exposures and smoking habits. Odds ratios were calculated for exposure before asthma onset, stratified by sex and age-class. The highest risks for asthma were associated with exposure to grain dust (odds ratio (OR) 4.2, 95% confidence interval (CI) 1.6-10.7) and flour dust (OR 2.8, 95% CI 1.1-7.2). Among males, significantly increased risks were observed after exposure to flour dust, welding fumes, man-made mineral fibres, and solvents. Among females, increased risks for asthma were associated with exposures to paper dust and textile dust. In logistic regression models controlling for age, smoking, sex and interacting exposures, increased risks were seen for welding fumes (OR 2.0, 95% CI 15-3.4), man-made mineral fibres (OR 2.6, 95% CI 1.4-7.3) and solvents (OR 2.2, 95% CI 1.2-3.2). The fraction of asthma attributed to occupational exposures after adjusting for sex, smoking and age was 11% (95% CI 7-14%). In conclusion, exposure to welding fumes, man-made mineral fibres, solvents and textile dust is associated with increased risk for asthma. (+info)
Bakery work, atopy and the incidence of self-reported hay fever and rhinitis.
(42/7400)
The aims of this study were to estimate the risk to bakers of developing hay fever and rhinitis, to assess the modifying effect of atopy and to estimate the occurrence of job change due to nasal symptoms. A retrospective cohort study was performed among bakers trained in Swedish trade schools from 1961 to 1989 (n=2,923). School control subjects (n=1,258) comprised students in other programmes in the trade schools and population controls (n=1,258) were randomly selected from the general population. A questionnaire on hay fever, rhinitis, the year of onset of these diseases, change of work due to nasal symptoms and work history was mailed to all participants. The atopic state of the responders was assessed by questions on allergic diseases in childhood and among next of kin. Incidence rates for hay fever and other rhinitis were calculated. The relative risk (RR) for hay fever when working as a baker compared with all control subjects combined was increased in males (RR=1.9, 95% confidence interval (CI) 1.2-2.9). The RR for rhinitis in male bakers compared with combined control subjects was 2.8 (95% CI 2.3-3.4) and for female bakers 2.0 (1.6-2.7). Of the bakers, 6.1% had changed job due to nasal symptoms, significantly more than the controls. A history of respiratory atopy increased the incidence rates of hay fever and rhinitis, with a synergistic effect between atopy and bakery work in males. In conclusion, Swedish bakers, mainly working in the 1970s and 1980s, had an approximately doubled risk of developing rhinitis. Male bakers also had an increased risk for hay fever. There was a synergistic effect of bakery work and atopy such as a family history of hay fever. Bakers also changed job due to nasal symptoms more often than control subjects. (+info)
Cough frequency and cough receptor sensitivity to citric acid challenge during a simulated ascent to extreme altitude.
(43/7400)
The aim of this study was to determine the frequency of cough and the citric acid cough threshold during hypobaric hypoxia under controlled environmental conditions. Subjects were studied during Operation Everest 3. Eight subjects ascended to a simulated altitude of 8,848 m over 31 days in a hypobaric chamber. Frequency of nocturnal cough was measured using voice-activated tape recorders, and cough threshold by inhalation of increasing concentrations of citric acid aerosol. Spirometry was performed before and after each test. Subjects recorded symptoms of acute mountain sickness and arterial oxygen saturation daily. Air temperature and humidity were controlled during the operation. Cough frequency increased with increasing altitude, from a median of 0 coughs (range 0-4) at sea level to 15 coughs (range 3-32) at a simulated altitude of 8,000 m. Cough threshold was unchanged on arrival at 5,000 m compared to sea level (geometric mean difference (GMD) 1.0, 95% confidence intervals (CI) 0.5-2.1, p=0.5), but fell on arrival at 8,000 m compared to sea level (GMD 3.3, 95% CI 1.1-10.3, p=0.043). There was no relationship between cough threshold and symptoms of acute mountain sickness, oxygen saturation or forced expiratory volume in one second. Temperature and humidity in the chamber were controlled between 18-24 degrees C and 30-60%, respectively. These results confirm an increase in cough frequency and cough receptor sensitivity associated with hypobaric hypoxia, and refute the hypothesis that high altitude cough is due to the inhalation of cold, dry air. The small sample size makes further conclusions difficult, and the cause of altitude-related cough remains unclear. (+info)
Sensitivity and exposure to indoor allergens in adults with differing asthma severity.
(44/7400)
In asthma, it is uncertain whether there is an association between degrees of exposure to domestic allergens and asthma severity. The pattern of sensitivity and exposure to common indoor allergens was examined in subjects with differing asthma severity. Sensitivity to house dust mite, dog and cat allergen and exposure to Der p 1, Can f 1 and Fel d 1 were assessed by skin prick tests and settled dust analysis in 28 subjects with severe asthma and 28 age- and sex-matched subjects with mild asthma (two declined skin prick test). All severe asthmatic subjects had at least one positive skin test and 20 of the 28 subjects were positive to all three allergens. Fourteen of the 26 subjects with mild asthma who took skin prick tests were positive to at least one, and one of these subjects was positive to the three allergens tested. Except for bedroom Fel d 1, the proportion of severe asthmatics both sensitized and exposed to each allergen at each site was significantly greater than the proportion sensitized and exposed in the mild asthma group. The geometric mean allergen concentrations, with the exception of bedroom Fel d 1, were greater in sensitized severe asthmatics than the sensitized mild asthmatics, which was significant for Der p 1 in bedroom samples and Can f 1 in bedroom and living room samples. These results support an association between the degrees of domestic allergen exposure in sensitized individuals and asthma severity. (+info)
Unintentional poisoning hospitalisations among young children in Victoria.
(45/7400)
OBJECTIVES: To describe the epidemiology of unintentional childhood poisoning hospitalisation in Victoria, Australia, in order to monitor trends and identify areas for research and prevention. METHODS: For children under 5 years, all Victorian public hospital admissions, July 1987 to June 1995, due to unintentional poisoning by drugs, medicines, and other substances were analysed. Similar cases were also extracted from the database of the Royal Children's Hospital intensive care unit, Melbourne for the years 1979-91. Log linear regression modelling was used for trend analyses. RESULTS: The annual average childhood unintentional poisoning rate was 210.7 per 100,000. Annual rates for males consistently exceeded those for females. The most common agents were those acting on the respiratory system and on smooth and skeletal muscles (muscle relaxants, cough and cold medicines, antiasthmatics), aromatic analgesics (paracetamol), and systemic agents (including antihistamines). Further investigation is justified for cardiac agents, some respiratory agents, and asthma medications. CONCLUSIONS: Childhood poisoning hospitalisation rates have not decreased in Victoria over recent years. A focused, agent specific approach, as well as a series of generic measures for the prevention of poisoning to children under 5 is advocated. The ongoing surveillance, collection and analysis of data, in addition to research on specific poisoning agents are essential components of any prevention strategy. (+info)
Pediatric practice based evaluation of the Steps to Prevent Firearm Injury program.
(46/7400)
OBJECTIVE: To estimate the prevalence of gun ownership and methods of gun storage in homes of pediatric patients before and after an educational intervention. DESIGN: Before and after trial. SETTING: Hospital based, inner city, pediatric primary care practice. PARTICIPANTS: Consecutive sample of parents of patients with appointments August to November 1994. INTERVENTION: Before the intervention, participants completed an anonymous questionnaire regarding ownership and storage of guns in their home. The intervention followed the Steps to Prevent Firearm Injury program of the American Academy of Pediatrics. It began after the parent completed the questionnaire and was reinforced at subsequent visits until July 1995. Families completing a baseline questionnaire and returning to the office July to October 1995 were resurveyed. MAIN OUTCOME MEASURE: Reported change in gun ownership and methods of storage. RESULTS: A gun(s) in the home was reported by 8.7% of respondents. Matched baseline and follow up questionnaires were available for 23.6% of families. In these, gun ownership reportedly decreased after intervention from 9.4% to 7.0%, handgun ownership fell from 5.4% to 3.0%, and long gun ownership fell from 6.1% to 5.5%. Storing guns outside of a locked container did not change from the baseline prevalence of 2.7%, but keeping any gun loaded fell from 1.6% to 0.5%. All p values were >0.05. CONCLUSION: This study was unable to demonstrate a statistically significant decline in gun ownership or improvement in gun storage after a practice based intervention designed to encourage these behaviors. (+info)
Detection of antibodies to hepatitis C virus in dried blood spot samples from mothers and their offspring in Lahore, Pakistan.
(47/7400)
Dried blood spot samples from mothers and their offspring attending the obstetric and pediatric departments of two hospitals in Lahore, Pakistan, were tested for antibodies to hepatitis C virus (HCV). The seroprevalence of HCV in the women was 6.7% (95% confidence interval [CI], 4.3 to 9.1), and that in the children was 1.3% (95% CI, 0.34 to 2.26). Four anti-HCV immunoglobulin G (IgG)-positive children had mothers that were anti-HCV IgG negative, which suggested that their infection was community acquired. (+info)
Systemic availability and pharmacokinetics of nebulised budesonide in preschool children.
(48/7400)
AIM: To evaluate the systemic availability and basic pharmacokinetic parameters of budesonide after nebulisation and intravenous administration in preschool children with chronic asthma. METHODS: Plasma concentrations of budesonide were measured for three hours after an intravenous infusion of 125 micrograms budesonide. The children then inhaled a nominal dose of 1 mg budesonide through the mouthpiece of a Pari LC Jet Plus nebuliser connected to a Pari Master compressor, and the plasma concentrations of budesonide were measured for another six hours. The amount of budesonide inhaled by the patient ("dose to subject") was determined by subtracting from the amount of budesonide put into the nebuliser, the amount remaining in the nebuliser after nebulisation, the amount emitted to the ambient air (filter), and the amount found in the mouth rinsing water. RESULTS: Ten patients aged 3 to 6 years completed both the intravenous and the inhaled treatment. The mean dose to subject was 23% of the nominal dose. The systemic availability of budesonide was estimated to be 6.1% of the nominal dose (95% confidence intervals (CI), 4.6% to 8.1%) or 26.3% of the dose to subject (95% CI, 20.3% to 34.1%). Budesonide clearance was 0.54 l/min (95% CI, 0.46 to 0.62), steady state volume of distribution 55 litres (95% CI, 45 to 68), and the terminal half life was 2.3 hours (95% CI, 2.0 to 2.6). CONCLUSIONS: Approximately 6% of the nominal dose (26% of the dose to subject) reached the systemic circulation of young children after inhalation of nebulised budesonide. This is about half the systemic availability found in healthy adults using the same nebuliser. (+info)