In studies of asthma in children, a common method is for the parents to complete questionnaires about their child's asthma symptoms. With longitudinal studies of asthma, children reach an age when they can complete the questionnaire themselves. The aim of this paper was to compare the prevalence of asthma symptoms as well as the agreement between responses to an asthma questionnaire completed by teenagers and their parents. As a part of the Obstructive Lung Disease in Northern Sweden Study (OLIN) pediatric study, where 3345, 13-14-yr-old children completed an asthma questionnaire, 294 (84%) randomly selected parents also completed the questionnaire, which included the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. There were no significant differences in the prevalence of wheeze in the last 12 months, ever asthma, or physician diagnosed asthma as reported by the parents compared with the teenagers. However, the teenagers reported a significantly higher prevalence of wheeze during or after exercise. The absolute agreement was generally very high while the level of agreement (kappa-value) was slightly lower. The highest results in both absolute agreement and kappa-value, were reached by the questions on diagnosis of asthma (98.9% and 0.93), use of asthma medicines (95.5% and 0.78), and whether the child ever had had asthma (97.2% and 0.86), respectively. In conclusion, the agreement between the parents' and the teenagers' responses to the asthma questionnaire was good. The change in methodology from parental to self-completion of the questionnaire did not affect the results in the study.
BACKGROUND: Two contradictory hypotheses have been proposed to explain the relationship between allergic conditions and malignancies, the immune surveillance hypothesis and the antigenic stimulation hypothesis. The former advocates that allergic conditions may be protective against development of cancer, whereas the latter proposes an increased risk. This relationship has been studied in several case-control studies, but only in a few cohort studies. METHODS: The association between allergic conditions and risk of developing leukemia, Hodgkin's disease, non-Hodgkin's lymphoma and myeloma was investigated in a cohort of 16,539 Swedish twins born 1886-1925. Prospectively collected, self-reported information about allergic conditions such as asthma, hay fever or eczema was obtained through questionnaires administered in 1967. The cohort was followed 1969-99 and cancer incidence was ascertained from the Swedish Cancer Registry. RESULTS: Hives and asthma tended to increase the risk of leukemia (relative risk [RR] = 2.1, 95% Confidence Interval [CI] 1.0-4.5 and RR = 1.6, 95% CI 0.8-3.5, respectively). There was also an indication of an increased risk of non-Hodgkin's lymphoma associated with eczema during childhood (RR = 2.3, 95% CI 1.0-5.3). CONCLUSION: In contrast to most previous studies, our results do not indicate a protective effect of allergic conditions on the risk of developing hematological malignancies. Rather, they suggest that allergic conditions might increase the risk of some hematological malignancies.
To examine the incidence of allergic rhinoconjunctivitis and asthma, and to assess allergic rhinoconjunctivitis as a risk factor for incident asthma, we performed a 11-year follow-up postal survey.
The original study population was a random population sample of 8000 inhabitants of Helsinki aged 20-69 years in 1996. Participants in the first postal questionnaire survey, 6062 subjects, were invited to this follow-up study, and provided 4302 (78%) answers out of 5484 traced subjects in 2007.
Cumulative incidence of asthma from 1996 to 2007 was 4.0% corresponding to an annual incidence rate of 3.7/1000/year. After exclusion of those with asthma medication or physician-diagnosed chronic bronchitis or COPD at baseline in 1996, the cumulative incidence decreased to 3.5% (incidence rate 3.2/1000/year), and further to 2.7% (2.5/1000/year) when also those reporting recurrent wheeze or shortness of breath during the last year in 1996 were omitted from the population at risk. Remission of asthma occurred in 43 subjects and was 16.9% over 11 years. Cumulative 11-year incidence of allergic rhinoconjunctivitis was 16.9% corresponding to 16.8/1000/year, and cumulative remission was 18.1%. Incidence of allergic rhinoconjunctivitis was significantly lower among those who had lived in the countryside or on a farm during the first 5 years of life, but this was not true for asthma. In multivariate analysis, farm living during the first 5 years of life was protective for the development of allergic rhinoconjunctivitis, OR 0.75 (95%CI 0.57-0.99). Allergic rhinoconjunctivitis was a significant independent risk factor for incident asthma, OR 2.15 (95%CI 1.54-3.02). In the cohort, the prevalence of rhinoconjunctivitis increased from 38.0% in 1996 to 40.9% in 2007, physician-diagnosed asthma from 6.8% to 9.4%, while current smoking decreased from 31.3% to 23.3%.
Incidence of allergic rhinoconjunctivitis was higher than in earlier studies, while asthma incidence remained on similar level, both being significantly higher in women. Allergic rhinoconjunctivitis doubled the risk for incident asthma.
To investigate the association between allergies, asthma, and breast cancer risk in a large, population-based case-control study.
Breast cancer cases (n = 3,101) were identified using the Ontario Cancer Registry and population controls (n = 3,471) through random digit dialing. Self-reported histories of allergies, hay fever, and asthma were collected by questionnaire. Logistic regression was used to assess associations between breast cancer risk and history of allergy/hay fever and asthma, with 16 possible confounders examined. Analyses were stratified by menopausal status.
A history of allergies or hay fever was associated with a small reduction in breast cancer risk [age-adjusted odds ratio (AOR) = 0.86, 95 % confidence interval (CI) 0.77-0.96] and did not differ by menopausal status. Asthma was not associated with breast cancer risk overall; however, among premenopausal women, asthma was associated with a reduced risk of breast cancer (AOR = 0.72, 95 % CI 0.54-0.97).
A history of allergies may be associated with a modest reduction in breast cancer risk. Asthma does not appear to be associated with breast cancer risk overall; however, asthma may be associated with reduced breast cancer risk among premenopausal women.
The association between asthma and type 1 diabetes, two chronic, immune-mediated diseases, has been of longstanding interest, but the evidence is still conflicting. We examined this association in a large, nationwide case-cohort study among Finnish children, using a novel statistical approach.
Among the initial cohort of all children born between 1 January 1981 and 31 December 2008, those who were diagnosed with asthma (n?=?81 473) or type 1 diabetes (n?=?9541) up to age 16 years by the end of 2009 were identified from the Central Drug Register maintained by the Social Insurance Institution of Finland. A 10% random sample from each initial birth year cohort was selected as a reference cohort (n?=?171 138). The association between asthma and type 1 diabetes was studied using a multistate modelling approach to estimate transition rates between healthy and disease states since birth. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated to represent the change in the transition rate between the disease states.
After adjusting for sex and birth decade, previous diagnosis of asthma increased the risk of subsequent type 1 diabetes by 41% (95% CI: 1.28, 1.54), whereas previous diagnosis of type 1 diabetes decreased the risk of subsequent asthma by 18% (95% CI: 0.69, 0.98).
The findings of the present study imply that the association between the diseases is more complex than previously thought, and its direction depends on the sequential appearance of the diseases.
BACKGROUND: There is some evidence that asthmatic women are more likely to have abnormal sex hormone levels. A study was undertaken to determine whether asthma and allergy were associated with irregular menstruation in a general population, and the potential role of asthma medication for this association. METHODS: A total of 8588 women (response rate 77%) participated in an 8 year follow up postal questionnaire study of participants of the ECRHS stage I in Denmark, Estonia, Iceland, Norway, and Sweden. Only non-pregnant women not taking exogenous sex hormones were included in the analyses (n = 6137). RESULTS: Irregular menstruation was associated with asthma (OR 1.54 (95% CI 1.11 to 2.13)), asthma symptoms (OR 1.47 (95% CI 1.16 to 1.86)), hay fever (OR 1.29 (95% CI 1.05 to 1.57)), and asthma preceded by hay fever (OR 1.95 (95% CI 1.30 to 2.96)) among women aged 26-42 years. This was also observed in women not taking asthma medication (asthma symptoms: OR 1.44 (95% CI 1.09 to 1.91); hay fever: OR 1.27 (95% CI 1.03 to 1.58); wheeze preceded by hay fever: OR 1.76 (95% CI 1.18 to 2.64)). Irregular menstruation was associated with new onset asthma in younger women (OR 1.58 (95% CI 1.03 to 2.42)) but not in women aged 42-54 years (OR 0.62 (95% CI 0.32 to 1.18)). The results were consistent across centres. CONCLUSIONS: Younger women with asthma and allergy were more likely to have irregular menstruation. This could not be attributed to current use of asthma medication. The association could possibly be explained by common underlying metabolic or developmental factors. The authors hypothesise that insulin resistance may play a role in asthma and allergy.
Maternal asthma has been associated with adverse pregnancy outcomes. Little is known about the influence of other atopic diseases on pregnancy outcomes. We assessed how various maternal atopic diseases might affect preterm birth, stillbirth, and neonatal death.
By linking Norwegian national registries, we acquired information on maternal health, socio-demographic factors, pregnancy, birth, and neonatal outcome on all births in Norway from 1967 to 2003.
A total of 1?974?226 births were included. Of these, 1.8% had a record of maternal asthma, 3.4% of maternal atopic dermatitis, and 0.4% of maternal allergic rhinoconjunctivitis. Overall rates of preterm birth, stillbirth, and neonatal death were 6.0%, 0.6%, and 0.5%, respectively. After adjustments for possible confounders, maternal asthma was associated with increased risk of preterm birth (relative risk (RR), 1.15, [95% confidence interval (CI) 1.10, 1.21]). In contrast, maternal atopic dermatitis was associated with decreased risk of preterm birth (RR 0.90, [95% CI 0.86, 0.93]), stillbirth (RR 0.70, [95% CI 0.62, 0.79]), and neonatal death (RR 0.76, [95% CI 0.65, 0.90]). Similarly, maternal allergic rhinoconjunctivitis was associated with decreased risk of preterm birth (RR 0.84, [95% CI 0.76, 0.94]) and stillbirth (RR 0.40, [95% CI 0.25, 0.66]).
We confirmed the previously reported association of maternal asthma with increased risk for preterm birth. Unexpectedly, maternal atopic dermatitis and allergic rhinoconjunctivitis were associated with decreased risk of preterm birth and stillbirth. Mechanisms for these protective associations are unclear, and our findings require confirmation in further studies.
This study from Danish general practice gives figures about the simultaneous prevalence of asthma and allergic rhinitis and the order of onset among 7662 patients, who during 1 year consulted for one or both of these diseases. Twenty-eight percent of patients with asthma consulted because they also had allergic rhinitis, and 17% of patients with allergic rhinitis consulted because they also had asthma. Age- and sex-distributions are presented. In 25% of patients with both diseases the onset of both diseases occurred within the same year, while in 35% the onset of asthma occurred first and in 40% allergic rhinitis. Among patients with both diseases, who did not have onset of both within the same year, more than 75% of them had onset of one disease within 2 years of the other.
We investigated the frequency of allergic disorders, the pattern of allergen sensitization and serum total IgE concentration in a population-based sample of schoolchildren screened on the basis of respiratory symptoms (N = 244). The children were classified on clinical grounds into three groups, asthma (N = 43), other symptoms from lower airways (OSLA; N = 34) and control children (N = 167). The frequency of allergic disorders (allergic rhinitis, conjunctivitis or dermatitis) differed significantly between children with asthma (81%), children with OSLA (62%) and in control children (48%) (p
A study was undertaken to determine the prevalence and impact of asthma in elementary school children in Fort Saskatchewan, Alberta. Questionnaires were distributed at all seven elementary schools and were completed by the parents. Of the 1,457 eligible students in grades one to six, questionnaires were returned for 1,083 (74%). A history of physician-diagnosed asthma was reported for 12.9% of the children: 16.0% of boys and 9.7% of girls. Currently, 9.9% of children had asthma: 11.6% of boys and 8.2% of girls. Compared to children without, those with asthma were more than 10 times as likely to have to limit their activities for a health reason (70.5% versus 6.6%), missed school more often for health reasons (32.7% versus 14.8% missed two or more days in the previous month), reported more "colds" in the previous year and were three times as likely to have had pneumonia. The prevalence of asthma is approximately twice as high as that found in children across Canada and underscores the need to determine risk factors for asthma in this population. The finding that 1 in 10 children had asthma emphasized the need for programs aimed at children with asthma.
Comment In: Can J Public Health. 1997 Mar-Apr;88(2):138-409170697