Prevalence of symptoms of asthma, rhinitis, and atopic eczema among adolescents living in urban and rural areas in different regions of Brazil

BackgroundIn Brazil, studies evaluating the prevalence of asthma and allergic diseases among children living in rural area compared to urban area are rare. Some authors identified as risk factors for higher prevalence of current wheezing to have a family history of asthma, to have contact with pets, and being student in an urban school. The International Study of Asthma and Allergies in Childhood (ISAAC) phase 3 has shown higher prevalence of wheezing, nasal symptoms and cutaneous rash in the last 12 months in centers from Northern (N) and Northeastern (NE) regions of Brazil.ObjectiveTo evaluate if adolescents with similar genetic background, living in a rural area are protected against the development of symptoms of asthma, rhinitis, and atopic eczema when compared to those living in an urban area in the same region of the country.Subjects and MethodAdolescents (13-14 year-old) living in Caruaru (Pernambuco) and in Santa Maria (Rio Grande do Sul) were enrolled in this study (2002-2003). The adolescents filled in the ISAAC written questionnaire (WQ), previously translated and validated to the Brazilian culture (30-32). Data obtained were transcribed manually into a database (Epi-Info) supplied by ISAAC's coordinators and were statistically analyzed by the SSPS-12 software.ResultsThe prevalence of asthma related symptoms were higher among those adolescents living in the urban centers in comparison to the rural ones. These differences were significant for wheezy ever, wheezy in the last 12 months, asthma ever, and wheezy with exercise in Caruaru and for wheezy ever and asthma ever, in Santa Maria. Comparing urban areas, the prevalence of asthma related symptoms in Caruaru was higher than in Santa Maria, except for wheezy ever and wheezy with exercise. The opposite was observed comparing rural areas: the prevalence of asthma (except for nocturnal cough) was higher in Santa Maria despite lesser severity of symptoms in this city.     

Obesity and Its Relationship with Asthma Prevalence and Severity in Adolescents from Southern Brazil

Obesity has been pointed out as a risk factor for higher prevalence of asthma and asthma-related symptoms in adolescents. The objective was to evaluate the relationship between the prevalence of asthma and obesity in adolescents living in Santa Maria and surroundings (state of Rio Grande do Sul, southern Brazil), applying the International Study of Asthma and Allergies in Childhood (ISAAC) protocol. A total of 4,010 of 6,123 schoolchildren, 13 to 14 years of age, enrolled in the ISAAC phase III protocol (asthma core questionnaire) and were nutritionally evaluated: height, weight, and triceps skinfold (TSF) measurements. Prevalence of asthma (wheeze in the last 12 months) and prevalence of severe asthma (two or more affirmative responses to: more than 4 acute attacks of asthma, speech disturbance, sleep disturbance, wheezing with exercise) were evaluated and compared according to their nutritional status: obese and non-obese. Obese adolescents were defined by body mass index (BMI, in kg/m²) ≥85th percentile and TSF ≥85th percentile. Obese and non-obese groups were compared for prevalence of asthma and asthma severity using the Chi-square test and odds ratio (OR) with 95% confidence interval. Analyzing all adolescents, we observed a significant positive relationship between the prevalence of obesity and affirmative responses to “wheeze ever” (OR = 1.28; 95% CI 1.08-1.52), “wheezing with exercise” (OR = 1.36; 95% CI 1.11-1.66), “asthma ever” (OR = 1.29; 95% CI 1.03-1.62), and severe asthma (OR = 1.55; 95% CI 1.12-2.14). Among the boys, there was a significant positive association between obesity and “wheeze ever” (OR = 1.49; 95% CI 1.13-1.86). In girls, there was a significant positive relationship with “asthma ever” (OR = 1.38; 95% CI 1.01-1.88) and “wheezing with exercise” (OR = 1.36; 95% CI 1.11-1.66). This cross-sectional study with adolescents living in the southern region of Brazil showed that there is a positive association between obesity and prevalence of asthma symptoms and asthma severity, a finding mainly confined to girls.     

Increase in prevalence of rhinoconjunctivitis but not asthma and atopic eczema in teenagers.

OBJECTIVE: We sought to assess changes in the prevalence of asthma and other allergic diseases in schoolchildren of Curitiba between 1995 and 2001. METHODS: Schoolchildren (aged 13-14) were evaluated by a self-reported written questionnaire of ISAAC protocol for symptoms of asthma and allergic diseases. The diagnoses of asthma, rhinoconjunctivitis and atopic eczema were considered according to the ISAAC protocol. Probable asthma was considered: more than 4 attacks of wheezing in the last 12 months; 1 to 3 attacks of wheezing in the last 12 months with dry cough at night, and/or with sleep disturbance due to wheezing, and/or with wheezing after exercise. The data obtained in 2001 were compared with the data obtained in 1995 for the same age group. RESULTS: We evaluated 2,946 schoolchildren in 1995 and 3.628 in 2001. The prevalence of symptoms of asthma, probable asthma, rhinoconjunctivitis and eczema in 1995 and 2001 was 18.4% and 18.7%, 11.6% and 12.4%, 14.2% and 17.2%, 3.8% and 3.7%, respectively. There was a 23.7% increase in the prevalence of rhinoconjunctivitis symptoms (p < 0.05). CONCLUSIONS: The prevalence of symptoms of asthma, probable asthma and eczema did not change over the past 6 years but a significant increase of the rhinoconjunctivitis symptoms was detected.     

Effects of active tobacco smoking on the prevalence of asthma-like symptoms in adolescents

The prevalence of asthma in adolescents markedly varies between different localities as found by the International Study of Asthma and Allergies in Childhood (ISAAC) and this may be due to environmental factors. Although tobacco smoke exposure is related to an increase in the prevalence of asthma, there is lack of information on that respect in children from developing countries, where active tobacco smoking usually starts early in adolescence. This study was undertaken to assess the effect of tobacco smoking on the prevalence of asthma symptoms in a random sample of 4738 adolescents aged 13.4 ± 1.05 years who responded the ISAAC video questionnaires plus questions on tobacco smoking. The prevalence of tobacco smoking in the last 12 months was 16.2%, with significant female predominance. The persistent smokers had a significantly higher prevalence of asthma-like symptoms ever and in the last 12 months (wheezing, wheezing with exercise, nocturnal wheezing, severe wheezing, and dry nocturnal cough) than ex-smokers and nonsmokers. More than 27% of asthma symptoms in our adolescents are attributable to active tobacco consumption (population attributable risk). This study strongly suggests that potent and more effective campaigns against tobacco smoking should be implemented in developing countries, where active tobacco smoking is dramatically increasing in children.     

Prevalence of Asthma and Asthma-Like Symptoms in Inner-City Schoolchildren

This study investigates the prevalence of asthma and asthma-related symptoms in New Orleans inner-city schoolchildren. A cross-sectional survey of 1535 elementary, middle, and high schoolchildren (aged 5-18) was conducted by using the International Study of Asthma and Allergies in Childhood (ISAAC) written questionnaire. Lifetime prevalence of wheezing was 39.4%, and lifetime prevalence of asthma was 24.4%. Wheezing during the previous 12 months was reported by 25.7% of the sample. Twenty-one percent of respondents reported having one or more attacks of wheezing per year, with 5.6% reporting four or more attacks per year. Many participants reported sleep disturbance (15.4%), with 6.2% reporting sleep disturbance more than once a week. The 12-month rate of speech limitation due to asthma exacerbation was 6.6%. Exercise-induced asthma was reported by 16.9% of the students, and nocturnal cough (not associated with cold) was reported by 27.3%. Overall, boys reported higher rates of symptoms than girls, and younger children (aged 6-7) reported greater symptoms than older children (aged 13-14). These findings show that prevalence of asthma in this population is elevated and the ISAAC written questionnaire successfully identified inner-city children at risk for asthma in New Orleans.     

Prevalence of asthma and other allergic diseases in school children from Juarez City, Chihuahua]

OBJECTIVE: To assess the prevalence and severity of asthma and allergic diseases in schoolchildren residing in Ciudad Juarez, Chihuahua. MATERIAL AND METHODS: A cross-sectional study was conducted from April 1998 to May 1999, among 6,174 children from 53 schools in Ciudad Juarez, Chihuahua. The method used was the one recommended by the International Study of Asthma and Allergies in Childhood (ISAAC) to determine the prevalence and severity of asthma, rhinitis, and eczema. Parents were asked to answer a standardized questionnaire on current and cumulative prevalence of asthma, rhinitis, and eczema. A sample stratified by level of pollution was selected. RESULTS: The cumulative prevalence of medically diagnosed asthma and wheezing was 6.8% (95% CI 6.2, 7.4) and 20% (95% CI 19.7, 21.8), respectively. The prevalence of wheezing in the last 12 months was higher in the group aged 6-8 years than in those aged 11-14 years (9.7% vs. 5.8%, p < 0.01). The prevalence of medically diagnosed rhinitis was 5.0% (95% CI 4.5, 5.6). The prevalence of medically diagnosed eczema was 4.9% (4.3, 5.4). The prevalence of eczema symptoms in the last 12 months was 12.7% in the 6-8 years group and 13.3% in the 11-14 year group, respectively. Severe symptoms of asthma were significantly higher in the 6-8 years group and during the autumn months. CONCLUSIONS: The prevalence of medically diagnosed and symptomatic asthma was relatively low in comparison with findings from others studies that use similar methods, but the prevalence rates of rhinitis and eczema were higher.     

Prevalence of asthma,rhinitis and eczema among 13–14-year-old schoolchildren in Tochigi,Japan

To analyze the prevalence and severity of asthma, rhinitis and eczema in children living in different countries, the International Study of Asthma and Allergies in Childhood (ISAAC) was developed. The ISAAC Phase One study evaluated approximately 720 000 children in 56 countries, including Japan. In late 1995 and early 1996, we administered the ISAAC questionnaire to 4466 schoolchildren aged 13–14 years of age in 24 schools in Utsunomiya City and Tochigi City (both in Tochigi Prefecture, Japan). With regard to asthma, the reported prevalence of wheezing in the preceding 12 months was 8.4%, of frequent wheezing attacks 0.6% and of wheezing with sleep disturbance 0.5%. The prevalence in the preceding 12 months of rhinitis was 42.1% and of rhinoconjunctivitis was 21.5%. Nasal symptoms were most frequent in April (19.9%) and least frequent in July (5.6%). The prevalence of atopic eczema in the prior 12 months was 9.6% and atopic eczema with sleep disturbance was 0.6%. All prevalence values were slightly increased in Utsunomiya City, the largest city in Tochigi Prefecture, in comparison with Tochigi City. In conclusion, in Japanese cities, 33.3% of children had some allergic symptoms and 2.4% of children reported severe allergic symptoms.     

Differences in prevalence of asthma, rhinitis, and eczema between parental and self-completed questionnaires in adolescents

This study was undertaken to compare, for the first time in a developing country, the prevalence of asthma, rhinitis, and eczema in children aged 13-14 years when questionnaires from the International Study of Asthma and Allergies in Childhood (ISAAC) were independently completed by children and parents. A random sample of 3,178 children completed the ISAAC questionnaire at school, while in another sample of 3,387 children, the questionnaire was completed by their parents at home. The prevalence of asthma, rhinitis, and eczema symptoms was significantly higher when questionnaires were completed by adolescents themselves rather than by the parents, particularly for those symptoms that could be better perceived by children or that were more severe, e.g., wheezing with exercise, severe episodes of wheezing, nocturnal cough, and awaking with wheezing in the last 12 months. The diagnosis of hay fever and eczema was also reported more frequently by adolescents compared to their parents. The prevalence of asthma ever and wheezing in the last 12 months was not significantly different between the two samples. In a randomly selected subset of 550 pairs where adolescents and parents came from the same family, asthma ever had the highest agreement (kappa = 0.72, 95% CI: 0.64-0.80), but agreement was poor for rhinitis and eczema ever. In conclusion, the prevalence of asthma, rhinitis, and eczema symptoms varied according to whether the information was reported by independent samples of adolescent or parents. However, the prevalence of wheezing in the last 12 months and asthma ever was quite similar between adolescents and parents, suggesting that these questions are crucial for assessing asthma in epidemiological studies.     

Asthma prevalence in children living in north Mexico City and a comparison with other Latin American cities and world regions.

Reports of previous studies done without following the international guidelines in different cities of Mexico showed a decrease in asthma prevalence. The aim of this study was to determine the prevalence and severity of asthma symptoms in children and teenagers living in north Mexico City and compare them with those of other Latin American cities and world regions. The cross-sectional survey followed the protocol of the International Study of Asthma and Allergies in Childhood IIIb phase survey. The study population included children 6-7 years old and teenagers 13-14 years old from randomly selected primary and secondary schools. There were 1629 boys and 1582 girls in the group of 6- to 7-year-old children and 2039 boys and 1860 girls in the 13- to 14-year-old group. "Wheezing or whistling in the chest at any time in the past" was present in 19.2% (95% confidence interval [CI], 17.9, 20.6) of the children and in 17.0% (95% CI, 15.8, 18.1) of the teenagers; "wheezing or whistling in the chest in the last 12 months" was reported in 6.8% (95% CI, 5.9, 7.6) of the children and 9.9% (95% CI, 9.0, 10.8) of the teenagers; "asthma ever" was claimed in 4.5% (95% CI, 3.8, 5.2) of the children and 8.0% (95% CI, 7.1, 8.8) of the teenagers. These prevalences were low compared with other ISAAC Latin American surveys and intermediate in comparison with worldwide regional prevalences reported by ISAAC surveys. The prevalence of asthma is low in Mexico City in comparison with other surveyed locations, but the number of patients with asthma makes it an important issue for Mexican public health programs.     

Prevalence of asthma symptoms in Latin America: the International Study of Asthma and Allergies in Childhood (ISAAC)

The prevalence of respiratory symptoms indicative of asthma in children from Latin America has been largely ignored. As part of the International Study of Asthma and Allergies in Childhood (ISAAC), 17 centers in 9 different Latin American countries participated in the study, and data from 52,549 written questionnaires (WQ) in children aged 13-14 years and from 36,264 WQ in 6-7 year olds are described here. In children aged 13-14 years, the prevalence of asthma ever ranged from 5.5-28%, and the prevalence of wheezing in the last 12 months from 6.6-27%. In children aged 6-7 years, the prevalence of asthma ever ranged from 4.1-26.9%, and the prevalence of wheezing in the last 12 months ranged from 8.6-32.1%. The lower prevalence in centers with higher levels of atmospheric pollution suggests that chronic inhalation of polluted air in children does not contribute to asthma. Furthermore, the high figures for asthma in a region with a high level of gastrointestinal parasite infestation, and a high burden of acute respiratory infections occurring early in life, suggest that these factors, considered as protective in other regions, do not have the same effect in this region. The present study indicates that the prevalence of asthma and related symptoms in Latin America is as high and variable as described in industrialized or developed regions of the world.     

Obesity and Its Relationship with Asthma Prevalence and Severity in Adolescents from Southern Brazil

Obesity has been pointed out as a risk factor for higher prevalence of asthma and asthma-related symptoms in adolescents. The objective was to evaluate the relationship between the prevalence of asthma and obesity in adolescents living in Santa Maria and surroundings (state of Rio Grande do Sul, southern Brazil), applying the International Study of Asthma and Allergies in Childhood (ISAAC) protocol. A total of 4,010 of 6,123 schoolchildren, 13 to 14 years of age, enrolled in the ISAAC phase III protocol (asthma core questionnaire) and were nutritionally evaluated: height, weight, and triceps skinfold (TSF) measurements. Prevalence of asthma (wheeze in the last 12 months) and prevalence of severe asthma (two or more affirmative responses to: more than 4 acute attacks of asthma, speech disturbance, sleep disturbance, wheezing with exercise) were evaluated and compared according to their nutritional status: obese and non-obese. Obese adolescents were defined by body mass index (BMI, in kg/m²) ≥85th percentile and TSF ≥85th percentile. Obese and non-obese groups were compared for prevalence of asthma and asthma severity using the Chi-square test and odds ratio (OR) with 95% confidence interval. Analyzing all adolescents, we observed a significant positive relationship between the prevalence of obesity and affirmative responses to “wheeze ever” (OR = 1.28; 95% CI 1.08–1.52), “wheezing with exercise” (OR = 1.36; 95% CI 1.11–1.66), “asthma ever” (OR = 1.29; 95% CI 1.03–1.62), and severe asthma (OR = 1.55; 95% CI 1.12–2.14). Among the boys, there was a significant positive association between obesity and “wheeze ever” (OR = 1.49; 95% CI 1.13–1.86). In girls, there was a significant positive relationship with “asthma ever” (OR = 1.38; 95% CI 1.01–1.88) and “wheezing with exercise” (OR = 1.36; 95% CI 1.11–1.66). This cross-sectional study with adolescents living in the southern region of Brazil showed that there is a positive association between obesity and prevalence of asthma symptoms and asthma severity, a finding mainly confined to girls.     

Risk factors associated to the prevalence of asthma in adolescence

The ISAAC project (International Study of Asthma and Allergies in Childhood) was developed with the purpose of determining the prevalence of asthma in schoool children, with the definition of two age groups: infancy, when asthma is more frequent, and adolescence, when mortality associated to asthma is greater. However, the study does not address the risk factors associated with this pathology. Our aim is to comparatively analyze the prevalence of respiratory symptoms and the asthma epidemiological factors in the two age groups and in both sexes. Since the results of ISAAC Phase I are available, we can study the variations in risk factors, relating them to the current prevalence of asthma. The prevalence of bronchial asthma in our adolescents is 10 % - this implying a significant increase with respect to the data corresponding to ISAAC Phase I. Likewise, the prevalence of wheezing in the last 12 months has also increased significantly with respect to the data corresponding to ISAAC Phase I. It can be affirmed that familial antecedents of asthma are significantly correlated to the fact of having experienced asthma at some point in time, or to wheezing in the previous 12 months. In the same way as for bronchial asthma, the increase in rhinitis has been significant. The presence of animals in the home is significantly associated to the fact of having experienced asthma at some point in time, though the presence of animals in the home has decreased significantly. An encouraging finding in our study is the fact that smoking has decreased significantly among adolescents in comparison with the previous data. However, the same does not apply to smoking among parents, which shows results similar to those recorded in the previous study - with an influence upon the same habit in the offspring. As in other studies, active smoker status is seen to be associated with the fact of having experienced asthma at some point in time. Although a common observation, the importance of hyper-responsiveness with exercise among adolescents is still not acknowledged, despite its significant correlation to the fact of having experienced asthma at some point in time, or wheezing in the previous 12 months.     

Prevalence of asthma in 13-14 yr-old schoolchildren across Israel.

There is evidence that the incidence and severity of asthma are increasing worldwide, but there are limited data on asthma in Israel. The aim of this study was to investigate the prevalence and severity of asthma and asthma symptoms in 13-14 yr-old schoolchildren in Israel. The self-completed questionnaire used was a modified version of that developed by the International Study of Asthma and Allergies in Childhood (ISAAC), and was administered to a national sample of 12,918 children. The prevalence of asthma ever, wheezing ever and wheezing in the last 12 months were 13.7, 23.8 and 17.9% respectively. Significantly higher rates of a history of asthma and asthma symptoms were observed in Jews compared with Arabs. Although asthma ever was more prevalent in males than in females, asthma symptoms were significantly more common in females. The type of area of residence had no effect on the prevalence of wheezing. The ethnic differences in the prevalence of asthma persisted after controlling for sex, district of residence and level of urbanization. The prevalence of both asthma and asthma symptoms in Israel are slightly above the mean reported from 10 other countries in Europe and the Far-East.     

Statewide Adolescent Asthma Surveillance

We assessed the prevalence of diagnosed asthma, wheezing, healthcare utilization, and environmental triggers in children ages 13-14 years, and evaluated the feasibility of statewide asthma surveillance in North Carolina. A cross-sectional study (N = 1596) was conducted using the International Survey for Asthma and Allergies in Childhood (ISAAC) questionnaire. Ten percent reported current diagnosed asthma. Nineteen percent reported wheezing symptoms with no diagnosis of asthma. Children with frequent wheezing were more likely to be poor, African-American, and female. Thirty percent of diagnosed asthmatics made 1 or more emergency room visits in the last year. Undiagnosed asthmatics were unmedicated. These results highlight the magnitude of the asthma epidemic in early adolescence, and illustrate that statewide surveillance using ISAAC is feasible.     

Urbanization and the risk of asthma among schoolchildren in the Palestinian Authority.

The aim of the present survey was to compare the prevalence of symptoms suggestive of asthma in boys and girls aged 6-7 and 13-14 years in a rural and an urban area in the West Bank. For this purpose, the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire was issued to 970 schoolchildren in the two regions. The response rate was 92.2%. The prevalences of ever wheezing in the urban and rural areas were 16.4% and 12.0%, respectively (p < 0.05); the 12-month prevalences of wheezing were 10.5% and 5.5%, respectively (p < 0.05); the prevalences of more severe wheeze were 4.5% and 1.7%, respectively (p < 0.05); and prevalences of diagnosed asthma were 4.2% and 2.8%, respectively (p = NS). When controlling for age by stratification, the significant association between prevalence rates and place of residence persisted in the 13-14-year age group. These results also show that the prevalence of asthma among Palestinian children is moderately high in comparison with that reported from developing countries, but lower than those reported from Western countries. This survey, the first epidemiological survey on asthma in the West Bank, demonstrates a marked difference between urban and rural areas. The findings emphasize the need for further study of the environmental determinants of the disease among Palestinian children.     

Regional Variation in Asthma Symptom Prevalence in Latin American Children

Objectives. This study investigates the distribution pattern of asthma symptom prevalence in Latin American children aged 13–14 years. Methods. A randomized, cross-sectional and multicentric study on the prevalence and severity of asthma symptoms (lifetime asthma, current wheezing, and frequent sleep disturbance by wheezing) was conducted in 165,917 schoolchildren from 56 centers in 17 Latin American countries, as part of the International Study of Asthma and Allergies in Childhood (ISAAC), Phase Three. Results. The prevalence of lifetime asthma prevalence ranged from 1.2% to 33.1%, whereas current wheezing went from 3.9% to 30.8% and frequent sleep disturbance from 0.6% to 6.1%. An important proportion of centers (55%) reported a prevalence of asthma symptoms over 15%. There was no significant correlation between asthma symptom prevalence and latitude, altitude, or tropical setting. At country level, the prevalence of asthma was not associated with gross national income (GNI), proportion of population under the poverty line, or ancestry. Conclusions. This study suggests that ecological interactions, probably typical for each locality, may be the main determinants for the large variability of asthma prevalence in Latin America. The high prevalence of asthma symptoms found in children living in areas with low socioeconomic development would challenge the protective role against asthma of factors related to low hygiene and poverty; contrarily, in this region they would act as risk factors.     

Agreement between written and video questions for comparing asthma symptoms in ISAAC.

Phase One of the International Study of Asthma and Allergies in Childhood (ISAAC) has reported the prevalence of asthma, rhinitis and eczema symptoms in children. In 99 centres from 40 countries, a total of just under 317,000 13-14-yr-old children also completed a video questionnaire, showing the symptoms and signs of asthma. This first video sequence has been compared to the ISAAC written question asking about current wheezing to explore variations in agreement and the contribution of each questionnaire to wheezing prevalence between centres, by region and language groups. In general, responses to the video questionnaire gave a lower prevalence than the siritten questionnaire and responses were closely correlated. The overall proportion of agreement was high, mean 0.89. but unbalanced, with good negative agreement but poor positive agreement. Chance corrected agreement using Cohen's kappa coefficient, was generally low, with onl 20 centres with kappa >0.4. The contribution of each questionnaire to wheezing prevalence also varied between centres and suggests that written questions about wheezing are variably understood and interpreted by 13-14 yr olds. International comparisons of wheezing and its audiovisual presentation suggest that adolescents interpret a written question about wheezing differently from its audiovisual presentation and that this interpretation shows variation between centres. This relationship and the interpretation of both written and audiovisual presentation of symptoms requires further study in order to better predict asthma.     

Risk factors affecting asthma prevalence in adolescents living in Istanbul,Turkey

BackgroundAsthma is one of the most important diseases of childhood. The aim of this study was to evaluate the prevalence of asthma symptoms and risk factors affecting asthma.MethodsIn a cross-sectional study design, 9991 children, aged 13–14 years in 61 primary schools in 32 districts of Istanbul were evaluated. Asthma prevalence among the children was assessed using the ISAAC protocol.ResultsIn our study, a total of 10,894 questionnaires were distributed to 13–14 years old children, and of these 9991 questionnaires were suitable for analysis with an overall response rate of 91.7%. The rates of wheeze ever, wheezing in last 12 months and lifetime doctor diagnosed asthma prevalence were 17.4%, 9.0%, and 11.8%, respectively. There were 4746 boys (47.9%) and 5166 girls (52.1%) with M/F ratio of 0.92. Atopic family history, fewer than three siblings living at home, tonsillectomy or adenoidectomy history, consumption of fermented foods, mixed pickles, margarine and meat were found to be associated with an increased asthma risk. Use of paracetamol in the last 12 months, consumption of fruit and animal fats acted as a protective factor against asthma. The Mediterranean-style diet was not associated with the prevalence of asthma.ConclusionsLifetime doctor diagnosed asthma prevalence was found to be 11.8% in 13–14 year olds. History of tonsillectomy and/or adenoidectomy and consumption of fermented foods, mixed pickles, margarine and meat may increase the symptoms of asthma. Usage of paracetamol and consumption of animal fats may be investigated as a protective factor against asthma.     

Preschool asthma in Italy: prevalence, risk factors and health resource utilization

Asthma in preschool children is greatly under-diagnosed worldwide. Aim was to investigate prevalence of wheezing, and asthma risk factors, doctor diagnosis, treatment and health resource utilization in preschool children. About 1402 children (3-5 years) attending local kindergartens participated in the study. The International Study of Asthma and Allergies in Childhood (ISAAC) written questionnaire (WQ) was used with additional questions on risk factors, asthma diagnosis, treatments, resource utilization. Allergic sensitisation was evaluated by skin prick tests for the common allergens. Prevalence of "wheezing in previous 12 months" and "doctor diagnosed asthma" were 12.1% and 8.6%, respectively. 4.7% of children have had both wheezing in the last 12 months and asthma diagnosis. Significant risk factors for wheezing were rhinitis, parental history of atopy and sensitivity to mites and grass pollens. 27.3% of children with asthma diagnosis, but only 4.9% of children without diagnosis, received regular treatment during the previous year (p<0.0001). Children with more than 4 episodes of wheezing a year received more frequently an asthma diagnosis, but 68.6% were not on regular treatment. Asthma diagnosis was associated with a significant increase in control visits for wheezing (p<0.0001). The prevalence of children requiring at least one hospital emergency visit in the previous year was not different among the two groups (83.3% vs. 82.5%). In preschool children the prevalence of wheezing and asthma is elevated. Preschool asthma seems to be under-treated with few cases receiving regular therapy. The social cost of the disease at this age seems to be elevated because of the high frequency of control and emergency visits.