Prevalence of asthma among schoolchildren in Patras, Greece: four questionnaire surveys during 1978-2003.

BACKGROUND: The prevalence of asthma and wheezing has risen during the past four decades. Recent reports suggest that the "asthma epidemic" has reached a plateau. OBJECTIVE: To examine further trends in the prevalence of childhood diagnosed asthma and wheezing in an urban environment in Greece. METHODS: A population-based cross-sectional parental questionnaire survey was repeated among third-grade and fourth-grade school children (8-10 years) of public primary schools in 2003 in the city of Patras, Greece, by using methods identical to that of surveys conducted in 1978 (completed questionnaires, n = 3003), 1991 (n = 2417) and 1998 (n = 3076). RESULTS: 2725 questionnaires were completed in the 2003 survey. The prevalence rates of current asthma and/or wheezing in 1978, 1991, 1998 and 2003 were 1.5%, 4.6%, 6% and 6.9%, respectively (p for trend <0.001). The lifetime prevalence of asthma and/or wheezing in the three more recent surveys was 8%, 9.6% and 12.4%, respectively (p for trend <0.001). The male:female ratios of current asthma and/or wheezing in the four surveys were 1.14:1, 1.15:1, 1.16:1 and 1.22:1, respectively. The proportion of those with wheezing diagnosed with asthma has increased during the study period, more so among non-current children with asthma. CONCLUSIONS: Our findings show a continuous increase in the prevalence of asthma and wheezing among preadolescent children in Patras, Greece, over 25 years, albeit at a decelerating rate. There seems to be a true increase in wheezing, despite some diagnostic transfer, particularly among younger children. The male predominance of the disease has persisted in the population of this study.     

Increase in chronic or recurrent rhinitis, rhinoconjunctivitis and eczema among schoolchildren in Greece: Three surveys during 1991–2003

The prevalence of allergic rhinitis, hay fever and eczema has risen worldwide during the last four decades but may have reached a plateau in some westernized societies. We examined time trends in the prevalence of childhood chronic or recurrent rhinitis, rhinoconjunctivitis and eczema in urban Greece. Using identical methodology, three population-based cross-sectional parental questionnaire surveys on current (last two years) and lifetime allergic symptoms of the nose, eyes and skin were performed among 8–10-yr-old children in 1991, 1998 and 2003 in Patras, Greece. Exactly 2417, 3006 and 2725 questionnaires were completed in 1991, 1998 and 2003, respectively. Prevalence rates of current (lifetime) symptoms of chronic or recurrent rhinitis were 5.1% (6.0%) for 1991, 6.5% (8.0%) for 1998 and 8.0% (9.8%) for 2003. Respective values for rhinoconjunctivitis were 1.8% (2.1%), 2.7% (3.4%) and 3.6% (4.6%) and for eczema 2.5% (4.5%), 3.4% (6.3%) and 5.0% (9.5%) (p for trend <0.001). Among current asthmatics there was an increase in lifetime rhinitis (p = 0.038), current (p = 0.025) and lifetime rhinoconjunctivitis (p = 0.007) and current (p = 0.001) and lifetime eczema (p < 0.001); male predominance increased throughout the study. The proportion of atopic asthma (current asthma with chronic or recurrent rhinitis and/or rhinoconjunctivitis and/or eczema) increased during the same period (p < 0.001). In conclusion, there is a continuous increase in the prevalence of allergic manifestations among preadolescent children in Patras, Greece during the period 1991–2003. In our population, boys have contributed to this increase more than girls and the increase of atopy is, at least partially, responsible for the increase of asthma.     

Eosinophil cationic protein and interleukin-8 levels in bronchial lavage fluid from children with asthma and infantile wheeze

It has been shown previously that airway eosinophils characterize childhood asthma and neutrophils contribute to the pathophysiology of both infantile wheezing and asthma. Therefore, eosinophil cationic protein (ECP) and interleukin‐8 (IL‐8) levels in bronchoalveolar lavage fluid (BALF) from asthmatics (n = 16) and infantile wheezers (n = 30) were analyzed as markers of eosinophil‐ and neutrophil‐mediated inflammation. To aid the interpretation, a control group of children (n = 10) with no lower airway pathology were included. Disease severity was assessed by using a symptom score. Surprisingly, no significant difference was found in IL‐8 or ECP levels among asthma, infantile wheeze, and control groups. Asthma was characterized by: a correlation between ECP levels and eosinophil counts (r = 0.618, p = 0.014); a correlation between neutrophil number and IL‐8 levels (r = 0.747, p = 0.002); and increasing IL‐8 levels with symptom score (p = 0.03). In infantile wheezers, IL‐8 levels were poorly related to neutrophil number but were significantly increased when neutrophils were > 10%. Although detectable levels were found in all but one symptomatic infant, IL‐8 concentrations did not reflect the symptom score in infantile wheeze. ECP was unexpectedly correlated to neutrophil percentages (Rho = 0.832, p = 0.001), and a threshold of ECP > 20 ng/ml was associated with persistent symptoms in these infantile wheezers. Hence, in accordance with BALF cellularity, activation of eosinophils was suggested by raised levels of ECP in childhood asthma, but not in infantile wheeze. Neutrophil‐mediated inflammation appeared to better reflect the severity of asthma than that of infantile wheeze. Although its meaning remains to be elucidated, ECP was suggested to be a helpful indicator of persistent infantile wheeze. However, its utility as a marker predicting ongoing asthma remains to be established.     

The prevalence of asthma and allergies in Singapore; data from two ISAAC surveys seven years apart

Background and Aims: Over the past few decades, the prevalence of asthma has been increasing in the industrialised world. Despite the suggestion of a similar increase in Singapore, the 12 month prevalence of wheeze among schoolchildren in 1994 was 2.5-fold less than that reported in western populations. It was hypothesised that with increasing affluence in Singapore, the asthma prevalence would further increase and approach Western figures. A second ISAAC survey was carried out seven years later to evaluate this hypothesis. Methods: The cross-sectional data from two ISAAC questionnaire based surveys conducted in 1994 (n = 6238) and in 2001 (n = 9363) on two groups of schoolchildren aged 6–7 and 12–15 years were compared. The instruments used were identical and the procedures standardised in both surveys. Results: Comparing data from both studies, the change in the prevalence of current wheeze occurred in opposing directions in both age groups—decreasing in the 6–7 year age group (16.6% to 10.2%) but increasing to a small extent in the 12–15 year age group (9.9% to 11.9%). The 12 month prevalence of rhinitis did not change; there was an increase in the current eczema symptoms in both age groups. Conclusion: The prevalence of current wheeze, a surrogate measure of asthma prevalence, has decreased significantly in the 6–7 year age group. Eczema was the only allergic disease that showed a modest increase in prevalence in both age groups.     

Hypertonic saline challenge tests in the diagnosis of bronchial hyperresponsiveness and asthma in children

The hypertonic saline challenge test is the recommended method to assess bronchial hyperresponsiveness in the International Study of Asthma and Allergies in Childhood (ISAAC). The sensitivity of this procedure to assess asthma symptoms, however, has been reported to vary among study centers. The purpose of our study was to evaluate the value of this provocation test in an epidemiological survey in children, and to relate the degree of bronchial hyperresponsiveness to the severity of asthma symptoms. All 11–13‐year‐old children from 16 randomly selected schools in Linköping, Sweden received a questionnaire regarding respiratory symptoms and allergic disease. Skin prick tests with eight inhalant allergens were performed. In addition, all children with wheeze over the past 12 months (current wheeze) and a random sample of children without current wheeze were invited to perform hypertonic saline provocation tests. A complete data set was available for 170 children, including 50 with and 120 without current wheeze. Bronchial hyperresponsiveness (BHR) was defined as at least 15% decline in FEV₁. The degree of BHR was represented by the response/dose ratio, i.e. the fall in FEV₁ divided by total dose of inhaled saline. The severity of asthma symptoms was classified by the number of wheezing episodes over the past 12 months. ‘Asthma ever’ was defined by a combination of symptoms in the questionnaires. Children with ‘asthma ever’ and current wheeze were considered as having current asthma. Current atopic asthma was defined as current asthma with at least one positive skin prick test. The sensitivity of the procedure to detect ‘asthma ever’, current asthma and current atopic asthma was 62, 61 and 83%, and the specificity 83, 81 and 60%, respectively. The positive challenge rate was 52, 34, 13 and 7% among current wheezers, previous wheezers, non‐wheezers with a history of allergy and healthy children. The degree of bronchial hyperresponsiveness increased with the number of wheezing episodes. Thus, the median and range of the response/dose ratio were 4.8%/ml (2.1–14.8), 2.6%/ml (0.7–8.6) and 1.3%/ml (0.8–2.7), respectively, for children with ≥ 4 episodes, 1–3 episodes and no wheezing episodes over the past 12 months (p<0.001). In conclusion, hypertonic saline provocation test is useful as a tool to detect asthma in epidemiological studies in children. The degree of bronchial hyperresponsiveness, as represented by the response/dose ratio, reflects the severity of asthma symptoms.     

Prevalence of asthma and bronchial hyperreactivity in Danish schoolchildren: no change over 10 years

Aim: To describe the point prevalence of current physician‐diagnosed asthma and bronchial hyperreactivity (BHR) in 2001 among unselected Danish schoolchildren aged 6–17 years, compared with the prevalence from a similar study from 1990 to 1991. Methods: Cross‐sectional study using parental questionnaire on asthma and respiratory symptoms combined with a 6‐min free running test with peak expiratory flow rate (PEFR) measurement (n = 1051, response rate 89.3%). Results were compared with those of a similar study in the same area from 1990 to 1991. Main outcome measures were current physician‐diagnosed asthma or BHR in children without physician‐diagnosed asthma measured by either a decrease in lung function after standardized running test and/or variability in PEFR on home monitoring. Results: The prevalence of current physician‐diagnosed asthma was 4.0% [95% confidence interval (CI) 2.7–5.3%] in 1990–1991 and 3.6% (95% CI 2.4–4.8%) in 2001. The prevalence of BHR was 3.2% (95% CI 2.0–4.4%) in 1990–1991 and 2.0% (95% CI 1.1–2.9%) in 2001. The combined prevalence was 7.2% (95% CI 5.4–8.9%) in 1990–1991 and 5.6% (95% CI 4.2–7.1%) in 2001. Conclusion: The point prevalence of current physician‐diagnosed asthma and BHR among unselected Danish schoolchildren aged 6–17 years was unchanged over 10 years between 1990–1991 and 2001.     

Epidemiological studies of the very high prevalence of asthma and related symptoms among school children in Costa Rica from 1989 to 1998

The aim of our study was to determine the prevalence of asthma and related respiratory symptoms in school children from Costa Rica during the last 10 years, from 1989 to 1998. Using nationally representative samples of school children from Costa Rica during the last 10 years we have performed three studies. Altogether 9931 children were investigated. The age groups: study I, 5–17 years (n = 2682), study II, 6–7 years (n = 2944), 13–14 years (n = 3200) and study III, 10 years (n = 1105). The diagnostic criteria for asthma used in these studies was as follows: study I (1989), diagnosis by a doctor in combination with the presence of four kinds of respiratory symptoms; studies II (1995) and III (1998), history of wheeze in the past 12 months. The two latter were part of the International Study of Asthma and Allergies in Childhood (ISAAC). A very high prevalence of a history of wheezing was found in the three studies (46.8%, 42.9%, and 45.1%) as well as a diagnosis of asthma (23.4%, 27.7% and 27.1%). The physician's diagnosis of asthma reported in the first study (23%) increased from 23.1 in study II to 27.7% in study III (p = 0.004). This increment could be a real increase in asthma prevalence, or be due to a better awareness about asthma. In study II the group of 6–7‐year‐olds had respiratory symptoms significantly more often than 13–14‐year‐olds (p < 0.001). Boys more often had a history of wheezing (p = 0.001), wheeze during the previous 12 months (p = 0.01) and an asthma diagnosis at the age of 6–7 years (p = 0.002) than girls, but girls had more respiratory symptoms than boys at the age of 13–14 years (p < 0.005). Wheezing in the past 12 months was more common for those living in urban areas aged 6–7 years (p = 0.04), and there was an increase of wheeze after exercise (p = 0.01). For the 13–14‐year‐olds the risk of wheezing was higher during the previous 12 months if they lived in temperate areas (<20°C) and at a high altitude (>1000 m). Living in a rural area and in a warm region (>20°C), increased the risk of dry cough during the previous 12 months in the group of 13–14‐year‐olds. In conclusion, Costa Rica is located in the tropics with a very high humidity, an enormous variety of flora and fauna and a very high prevalence of mite and cockroach allergens, which provide important risk factors that may explain the high prevalence of asthma and asthma‐related symptoms. Further possible factors, such as the change towards a more Western life style, resulting in fewer infections and parasitic diseases in the first years of life and changes in bedding material, may also be unresolved. Increased environmental pollution may add to the very high prevalence of asthma and related respiratory symptoms. The very extensive exposure to mites and cockroaches in bed material and in homes with poor ventilation may be an important factor, but many asthmatic children behave as non atopic, with a viral respiratory infection as a major precipitating factor.     

Prevalence of asthma among schoolchildren in Patras, Greece: four questionnaire surveys during 1978-2003

Background

The prevalence of asthma and wheezing has risen during the past four decades. Recent reports suggest that the “asthma epidemic” has reached a plateau.

Objective

To examine further trends in the prevalence of childhood diagnosed asthma and wheezing in an urban environment in Greece.

Methods

A population‐based cross‐sectional parental questionnaire survey was repeated among third‐grade and fourth‐grade school children (8–10 years) of public primary schools in 2003 in the city of Patras, Greece, by using methods identical to that of surveys conducted in 1978 (completed questionnaires, n = 3003), 1991 (n = 2417) and 1998 (n = 3076).

Results

2725 questionnaires were completed in the 2003 survey. The prevalence rates of current asthma and/or wheezing in 1978, 1991, 1998 and 2003 were 1.5%, 4.6%, 6% and 6.9%, respectively (p for trend <0.001). The lifetime prevalence of asthma and/or wheezing in the three more recent surveys was 8%, 9.6% and 12.4%, respectively (p for trend <0.001). The male:female ratios of current asthma and/or wheezing in the four surveys were 1.14:1, 1.15:1, 1.16:1 and 1.22:1, respectively. The proportion of those with wheezing diagnosed with asthma has increased during the study period, more so among non‐current children with asthma.

Conclusions

Our findings show a continuous increase in the prevalence of asthma and wheezing among preadolescent children in Patras, Greece, over 25 years, albeit at a decelerating rate. There seems to be a true increase in wheezing, despite some diagnostic transfer, particularly among younger children. The male predominance of the disease has persisted in the population of this study.Several studies have reported a rise in the prevalence of childhood asthma in Western countries over the past 3–4 decades. This increase can be, at least partially, explained by changes in diagnostic criteria and increased public awareness of the disease.¹ Those few serial studies that have used identical methods support the impression of a true increase in the prevalence of childhood asthma.^2,3,4,5,6,7 However, recently reported trends show no further increase in the prevalence of asthma, suggesting that the asthma epidemic may have reached a plateau.^8,9,10,11Using a standard parental questionnaire, the increasing prevalence of asthma was shown among 8–10‐year‐old school children in Patras, Greece, in 1978, 1991 and 1998.⁶ In this study, we hypothesised that a plateau in the prevalence of asthma has been reached in the city of Patras as well. To test this hypothesis, we performed another survey in 2003 using the same method as in the previous years and reanalysed the data, including sex analysis of the prevalence of asthma over the whole 25‐year surveillance period.     

Adherence to the Mediterranean type of diet is associated with lower prevalence of asthma symptoms,among 10–12 years old children: the PANACEA study

To cite this article: Arvaniti F, Priftis KN, Papadimitriou A, Papadopoulos M, Roma E, Kapsokefalou M, Antracopoulos MB, Panagiotakos DB. Adherence to the Mediterranean type of diet is associated with lower prevalence of asthma symptoms, among 10–12 years old children: the PANACEA study. Pediatr Allergy Immunol 2011; 22 : 283–289. Epidemiological studies have shown several associations between asthma symptoms and dietary factors. The aim of this work was to evaluate the relationship between adherence to the Mediterranean diet and childhood asthma. A cross‐sectional analysis was performed on 700 children (323 boys), 10–12 yr old, selected from 18 schools located in Athens greater area. Children and their parents completed questionnaires, which evaluated, among others, dietary habits. Asthma was defined according to ISAAC II criteria. Adherence to the Mediterranean diet was evaluated using the KIDMED score (theoretical range 0–12). Higher KIDMED score corresponds to greater adherence to the Mediterranean diet. Greater adherence to the Mediterranean diet was inversely associated with ever had wheeze (p = 0.001), exercise wheeze (p = 0.004), ever had diagnosed asthma (p = 0.002) and with any asthma symptoms (p < 0.001). One‐unit increase in the KIDMED score was associated with 14% lower likelihood of having asthma symptoms (odds ratio = 0.86, 95% confidence interval 0.75–0.98), after adjusting for various confounders. No significant associations were found between asthma symptoms and consumption of fruits (p = 0.25), vegetables (p = 0.97), legumes (p = 0.76), cereals (p = 0.71), dairy (p = 0.61), salty snacks (p = 0.53), or margarine/butter (p = 0.42) consumption, while increased fish and meat intake was associated with less asthma symptoms (p = 0.04 and p = 0.01, respectively). Our findings suggest an inverse relationship between level of adherence to the Mediterranean diet and prevalence of asthma in school‐aged children.     

The prevalence of asthma and allergies in Singapore; data from two ISAAC surveys seven years apart.

BACKGROUND AND AIMS: Over the past few decades, the prevalence of asthma has been increasing in the industrialised world. Despite the suggestion of a similar increase in Singapore, the 12 month prevalence of wheeze among schoolchildren in 1994 was 2.5-fold less than that reported in western populations. It was hypothesised that with increasing affluence in Singapore, the asthma prevalence would further increase and approach Western figures. A second ISAAC survey was carried out seven years later to evaluate this hypothesis. METHODS: The cross-sectional data from two ISAAC questionnaire based surveys conducted in 1994 (n = 6238) and in 2001 (n = 9363) on two groups of schoolchildren aged 6-7 and 12-15 years were compared. The instruments used were identical and the procedures standardised in both surveys. RESULTS: Comparing data from both studies, the change in the prevalence of current wheeze occurred in opposing directions in both age groups--decreasing in the 6-7 year age group (16.6% to 10.2%) but increasing to a small extent in the 12-15 year age group (9.9% to 11.9%). The 12 month prevalence of rhinitis did not change; there was an increase in the current eczema symptoms in both age groups. CONCLUSION: The prevalence of current wheeze, a surrogate measure of asthma prevalence, has decreased significantly in the 6-7 year age group. Eczema was the only allergic disease that showed a modest increase in prevalence in both age groups.     

Prevalence of and factors associated with current asthma symptoms in school children aged 6–7 and 13–14 yr old in Bogotá, Colombia

This cross‐sectional study of children aged 6–7 years and adolescents aged 13–14 years in Bogotá, Colombia, assessed the prevalence of asthma symptoms and their associations with dietary, health, and behavioral habits. This study is part of the International Study of Asthma and Allergies in Childhood (ISAAC)‐phase III. Asthma prevalence among the children was assessed using a parental self‐administered written questionnaire (WQ), and among adolescents using a WQ together with a video questionnaire (VQ). Associations were estimated with bivariate and multivariate analysis. The study found that the 6–7 year age‐group were more likely to report current asthma symptoms than the 13–14 year age‐group (10.4% [WQ] vs. 8.6% [WQ] and 8.0% [VQ], respectively). Factors associated with current asthma symptoms among the 6–7 year age‐group included higher maternal education (OR = 1.7, [95% CI 1.2–2.6], p = 0.007), a cat in the home during the last year (OR = 1.5, [95% CI 1.0–2.3], p = 0.036), watching TV 1–2 hours/day (OR = 2.1, [95% CI 1.2–3.9], p = 0.013), and medication with acetaminophen in the first and most recent year of life (OR = 1.8, [95% CI 1.3–2.4], p < 0.001; OR = 2.2, [95% CI 1.7–2.8], p < 0.001, respectively) or antibiotics in the first year of life (OR = 1.9, [95% CI 1.4–2.5], p < 0.001). Among the 13–14 year age‐group, factors associated with current asthma symptoms included medication with acetaminophen during the last year (OR = 1.8, [95% CI 1.4–2.3], p < 0.001); cereal, milk, and fruit consumption 3 or more times weekly (OR = 1.5, [95% CI 1.1–1.9], p = 0.010; OR = 0.8, [95% CI 0.6–1.0], p = 0.046; OR = 0.6, [95% CI 0.4–1.0], p = 0.031, respectively). Overall, compared with that in other Latin American centers, asthma prevalence in Bogotá is close the lower estimates. However, associations with dietary, health, and behavioral habits need further study to assess their complex relationship with asthma.     

The clinical expression of asthma in schoolchildren has changed between 1996 and 2006

Andersson M, Bjerg A, Forsberg B, Lundbäck B, Rönmark E. The clinical expression of asthma in schoolchildren has changed between 1996 and 2006.
Pediatr Allergy Immunol 2010: 21: 859–866.
© 2010 John Wiley & Sons A/S Several studies have reported diverging trends in the prevalence of asthma and wheeze. The aim of this study was to investigate the clinical expression of childhood asthma in 1996 and 2006 by studying asthma morbidity, treatment, and environmental exposures in school children with physician‐diagnosed asthma and wheeze, respectively. All children enrolled in first or second grade (7–8 yr‐old) in three municipalities in northern Sweden were invited to a questionnaire study in 1996 and 2006, respectively. In 1996, 3430 (97%) participated; and in 2006, 2585 (96%) participated. The same parental completed questionnaire, including the ISAAC questions, was used in both surveys. Physician‐diagnosed asthma was reported at 5.7% in 1996 and 7.4% in 2006. A significantly greater proportion of children with asthma were using inhaled corticosteroids (ICS) in 2006, 67% vs. 55% in 1996. This increase was parallel to a major decrease in severe asthma symptoms such as disturbed sleep because of wheeze (49% vs. 38%) and troublesome asthma (21% vs. 11%). The prevalence of current wheeze among the asthmatics decreased significantly; however, this was seen only among children not using ICS. Parental smoking decreased significantly as did the proportion living in damp buildings. In conclusion, although asthma remains a major public health issue in school age children, children with asthma had less respiratory symptoms and a better asthma control in 2006 compared to 1996. This parallels with an increase in treatment with ICS, more beneficial environmental conditions, and an increased diagnostic intensity resulting in a larger proportion of children with mild symptoms being diagnosed as having asthma.     

Rhinitis in 10-year-old children and early life risk factors for its development

Aim: To study the prevalence, characteristics of and risk factors for childhood rhinitis. Methods: In a whole population birth cohort study (n = 1456) the prevalence and characteristics of rhinitis among 10-y-old children were examined. At this age 1373 children (94%) completed standardized questionnaires, 1043 (72%) skin-prick testing, 953 (65%) serum inhalant immunoglobulin E antibody screening and 784 (54%) methacholine bronchial challenges. Results: At the age of 10 y the prevalence of hayfever ever was 18.6% and current nasal symptoms (rhinitis) 22.6%. Rhinitis at 10 y was largely seasonal and associated with low morbidity, although 62.7% of cases required pharmacological treatment. Atopy (positive skin test) and other allergic states were associated with rhinitis (p 3 0.001). Wheeze or diagnosed asthma was higher with coexistent rhinitis. Among wheezing children physician-diagnosed asthma (p 3 0.024) and inhaled corticosteroid use (p 3 0.001) were greater with the presence of rhinitis. Significant bronchial hyperresponsiveness (methacholine concentration giving a 20% fall in forced expiratory volume in 1 s 34.0 mg ml 31 ) was greater if rhinitis was present even when the child did not wheeze (p 3 0.001). Risk factor analysis for rhinitis identified the independent significance for atopy (p 3 0.001) and eczema ( p = 0.009) at the age of 4 y plus paternal rhinitis (p 3 0.001), maternal rhinitis ( p = 0.033) and maternal food allergy ( p = 0.016). Conclusion: Rhinitis is common at the age of 10 y, with strong associations with atopy, wheezing, asthma and bronchial hyperresponsiveness. An inherited predisposition towards atopy appears to predominate over environment in the aetiology of this state.     

Time trends of the prevalence of asthma and allergic disease in Austrian children.

After a substantial increase in the prevalence of atopic disease in Europe, recent studies indicate that a plateau has been reached. However, variation across countries and age groups exists. We studied the prevalence and time trends of asthma and allergic disease among schoolchildren in Austria, a country with traditionally low rates of asthma, hay fever, and eczema. As part of the International Study of Asthma and Allergies in Childhood (ISAAC), symptoms and physician diagnoses of asthma and allergic disease of 13,399 Austrian children aged 6-7 yr and 1516 children aged 12-14 yr were surveyed between 1995 and 1997. A similar survey was conducted between 2001 and 2003. Among children aged 6-7 yr, significant increases were seen in the prevalence of physician-diagnosed asthma (+16%; p = 0.013), hay fever (+22%; p < 0.001), and eczema (+37%; p < 0.001) between 1995 and 2003. These changes were paralleled by an increase in the prevalence of symptoms typical for hay fever (itchy eyes and runny nose), but not by an increase in wheeze. Among children aged 12-14 yr, the lifetime prevalence of diagnosed asthma increased by 32%, of hay fever by 19%, and of eczema by 28% (all, p < 0.001). These changes were paralleled by increases in the prevalence of wheezing as documented by both questions before and after a video showing wheezing children but not by symptoms typical for hay fever such as itchy eyes and runny nose. In conclusion, in Austria, contrary to other European countries, the prevalence of asthma and allergic disease increased among schoolchildren. Additional studies are needed to continue monitoring the dynamics of the prevalence of asthma and allergic disease in Austria and to explore trends in their risk factors.     

Clinical significance of cough and wheeze in the diagnosis of asthma

OBJECTIVES: (1) To determine the prevalence of cough, wheeze, and breathlessness, both as single symptoms and in combination, in primary schoolchildren and their relation to doctor diagnosed asthma. (2) To identify in areas with different levels of dust pollution whether questionnaire reported 'cough alone' (without wheeze or breathlessness) had similar risk factors to the questionnaire reported triad of 'cough, wheeze, and breathlessness'. SUBJECTS AND METHODS: Two cross sectional community surveys of primary schoolchildren (5-11 years) were performed in 1991 and 1993. Parent completed questionnaires related to socioeconomic and respiratory factors were distributed through 15 schools in three areas of Merseyside, one of which had a relatively high level of dust pollution. Data were analysed to determine the prevalence of different respiratory symptom patterns. Univariate and multiple logistic regressions were used to investigate the associations between respiratory symptom profiles and potential risk factors. RESULTS: The proportions of completed questionnaires that were returned were similarly high in both surveys, 92% in 1991 (1872 of 2035) and 87% in 1993 (3746 of 4288). The proportions of children with different respiratory symptom patterns were similar in the two surveys: in 1991, asymptomatic children 70.1% (1109 of 1583), those with cough alone 8.9% (141 of 1583), and children with the symptom triad of cough, wheeze, and breathlessness 8.3% (132 of 1583); the figures for 1993 were 69.5% (2144 of 3083), 9.2% (284 of 3083), and 7.3% (224 of 3083) respectively. The prevalence of doctor diagnosed asthma increased from 17.4% in 1991 to 22.1% in 1993. The symptom of cough alone was associated with going to school in an area of increased air pollution. The symptom triad of cough, wheeze, and breathlessness was associated with reported allergies, familial history of atopy and preterm birth. In 1991, of children with the symptom of cough alone one in eight were diagnosed asthmatic; twice as many doctors made the diagnosis on this basis in 1993. CONCLUSION: The respiratory symptom of cough alone and cough, wheeze, and breathlessness represent clinical responses to different specific risk factors. Cough alone was associated with the environmental factors of school in the dust exposed zone and dampness in the home, whereas cough, wheeze, and breathlessness related to allergic history and preterm birth, and may be the best surrogate of asthma. Diagnosis of asthma on the basis of cough alone partly explains the increased prevalence of doctor diagnosed asthma, especially in dust polluted areas.     

Clinical significance of cough and wheeze in the diagnosis of asthma.

OBJECTIVES: (1) To determine the prevalence of cough, wheeze, and breathlessness, both as single symptoms and in combination, in primary schoolchildren and their relation to doctor diagnosed asthma. (2) To identify in areas with different levels of dust pollution whether questionnaire reported ''cough alone'' (without wheeze or breathlessness) had similar risk factors to the questionnaire reported triad of ''cough, wheeze, and breathlessness''. SUBJECTS AND METHODS: Two cross sectional community surveys of primary schoolchildren (5-11 years) were performed in 1991 and 1993. Parent completed questionnaires related to socioeconomic and respiratory factors were distributed through 15 schools in three areas of Merseyside, one of which had a relatively high level of dust pollution. Data were analysed to determine the prevalence of different respiratory symptom patterns. Univariate and multiple logistic regressions were used to investigate the associations between respiratory symptom profiles and potential risk factors. RESULTS: The proportions of completed questionnaires that were returned were similarly high in both surveys, 92% in 1991 (1872 of 2035) and 87% in 1993 (3746 of 4288). The proportions of children with different respiratory symptom patterns were similar in the two surveys: in 1991, asymptomatic children 70.1% (1109 of 1583), those with cough alone 8.9% (141 of 1583), and children with the symptom triad of cough, wheeze, and breathlessness 8.3% (132 of 1583); the figures for 1993 were 69.5% (2144 of 3083), 9.2% (284 of 3083), and 7.3% (224 of 3083) respectively. The prevalence of doctor diagnosed asthma increased from 17.4% in 1991 to 22.1% in 1993. The symptom of cough alone was associated with going to school in an area of increased air pollution. The symptom triad of cough, wheeze, and breathlessness was associated with reported allergies, familial history of atopy and preterm birth. In 1991, of children with the symptom of cough alone one in eight were diagnosed asthmatic; twice as many doctors made the diagnosis on this basis in 1993. CONCLUSION: The respiratory symptom of cough alone and cough, wheeze, and breathlessness represent clinical responses to different specific risk factors. Cough alone was associated with the environmental factors of school in the dust exposed zone and dampness in the home, whereas cough, wheeze, and breathlessness related to allergic history and preterm birth, and may be the best surrogate of asthma. Diagnosis of asthma on the basis of cough alone partly explains the increased prevalence of doctor diagnosed asthma, especially in dust polluted areas.     

Epidemiologie des Asthma bronchiale

A large variability in the prevalence of childhood asthma was found among subjects enrolled in the International Study of Asthma and Allergies in Childhood (ISAAC study). Up to 20-fold differences were found between regions with low and high prevalences, respectively. Within Europe an East-West-gradient has been documented showing significantly reduced prevalences in eastern European countries. Urban-rural differences in the prevalence of asthma have furthermore been found in Africa, whereas in Europe significant effects have been found in farming environments within rural areas. There is increasing evidence to suggest that the prevalence of asthma has increased over the past decades, but it remains unclear whether this trend has reached a plateau. When considering the natural course of wheezing illnesses in childhood, heterogeneity of these conditions emerges. Wheezing episodes in infancy might be attributable to other mechanisms then asthma attacks in school age children. Some infant wheezers may show decrements of pulmonary function before the occurrence of any wheeze, while in preschool and school age two main wheezing phenotypes may be identified: viral associated and atopy related wheezing. The importance of such distinctions for the management of childhood asthma and wheeze awaits, however, further elucidation.     

Allergy: a systemic disease? The HUNT and Young–HUNT study,Norway.

A systemic nature of allergic diseases has been hypothesized. As part of this discussion, we studied if adolescent allergic wheeze and increasing combinations of allergic organ involvements (lung, nose and skin) would also increase the reporting of other health problems (headache, muscle pain and abdominal pain). In addition, we studied if parental asthma was associated with adolescent clustering of allergic expressions and if parental asthma with additional health problems (headache or muscle pain) was associated with adolescent reporting allergy in combination with headache, muscle pain and abdominal pain. Adolescents 13–19 yr (n = 8817, 89%) participated in the Young–HUNT study, Norway, 1995–97. Parental data on asthma were eligible in n = 5620. Health and lifestyle were measured by questionnaires and interviews. Associations with additional health problems were significantly strengthened with combinations of wheeze and other allergic expressions. Odds Ratio for associations ‘wheeze only’, ‘wheeze and rhinitis’ and ‘wheeze, rhinitis and eczema’ were for headache 2.1, 3.4 and 3.7; for muscle pain 2.8, 3.2 and 4.9; for abdominal pain 3.6, 4.0 and 4.9. All p for trend were <0.010. Similar results were obtained when studying allergic wheeze; p for trend <0.001. Parental asthma was associated with clustering of adolescent allergic expressions, and parental asthma with headache or muscle pain was significantly associated with reported allergy combined with similar health problems in their offspring. The results indicate that allergy may be expressed beyond organs commonly viewed as part of an allergic disease, and hence may support a hypothesis of a systemic nature of allergic diseases.     

The prevalence of respiratory symptoms and asthma among school children in three different areas of Norway

The role of exposure to ambient air pollution has been a topic of interest as a potential risk factor for respiratory symptoms and asthma. We expected that the prevalence rates would vary in Norway between the capital, Oslo, the mountainous area Hallingdal and the industrial area Odda. Surveys were conducted in school children, aged 6-16 years, in; Oslo (n=2577), Hallingdal (n=1177) and Odda (n=831). The parent-reported prevalence of wheeze in past year was almost similar in Oslo (13. 1 (95% CI 11. 7-14. 5)) and Upper Hallingdal (14. 2 (13. 1–15. 3)), but lower in Odda (9. 0 (7. 0–11. 0)). The findings for severe respiratory symptoms were almost equal. The age patters within each area differed. The risk of wheeze ever (p < 0.001) and wheeze in past year (p=0.04) decreased with increasing age in Odda, while there was an increase in the risk of exercise induced wheeze in Oslo (p=0.02) and Hallingdal (p < 0.001). The lifetime prevalence of asthma was lowest in Odda (5. 4 (3. 8–7. 0)) compared to Oslo (9. 4 (8. 2–10. 6)) and Hallingdal (8. 5 (6. 8–10. 2)). There was a positive association between physical activity and wheeze in past year. The results do not support the hypothesis that respiratory morbidity is more common in urban than rural areas, age and physical activity can influence the prevalence rates of respiratory symptoms in school children.     

Recurrent wheeze in children with Down syndrome: is it asthma?

Aim: To compare the prevalence of current wheeze in children with Down syndrome (DS), their siblings, and nonrelated population controls. Methods: This was a case–control study in which the International Study of Asthma and Allergy in Childhood questionnaire for respiratory symptoms was completed by parents for 130 children with DS, 167 of their siblings, and for 119 age‐ and sex‐matched control subjects from the general population. Results: Both wheeze ever and wheeze during the last 12 months was more commonly reported in DS than in their siblings or controls. The relative risk (RR) of current wheeze in DS was 2.8 (95% CI, 1.42–5.51) compared with siblings, and 2.75 (95% CI, 1.28–5.88) compared with controls. A doctor’s diagnosis of asthma was found in 3.1% in children with DS, in 4.2% in siblings and in 6.7% in controls. During 4‐years follow‐up, the diagnosis of asthma could not be confirmed in the 24 DS children with current wheeze, and atopy was found in none of them. Conclusion: Wheeze is common in children with DS. This is likely to be related to the factors specific for DS and probably unrelated to asthma.