Satellite symposium: Asthma in the World. Asthma among children in Latin America

The prevalence of respiratory symptoms related to asthma in children from Latin America has been largely ignored. This region participated in phases I and III of the International Study of Asthma and Allergies in Childhood (ISAAC) with 17 participating centers in phase I and 78 centers in phase III. Data were obtained on asthma, rhinitis and eczema from countries and centers with markedly different climactic, cultural and environmental conditions and socioeconomic development. The results for phase I are presented herein because data from phase III are currently being revised at the ISAAC international data control center and will be officially available in the second half of 2004. Phase I provided important information on the prevalence of asthma in the participating countries and demonstrated wide variation among centers in the same country and among countries. The participating Latin American countries are all developing countries and share more or less the same problems related to low socioeconomic status. Therefore, the results and figures should be analyzed within that context. The range for accumulative and current asthma symptoms in children from the Latin American countries that participated in phase I (89,000) were as follows: the prevalence of asthma ranged from 5.5% to 28% in children aged 13-14 years and from 4.1% to 26.9% in children aged 6-7 years. The prevalence of wheezing in the previous 12 months ranged from 6.6% to 27% in children aged 13-14 years and from 8.6% to 32.1% in children aged 6-7 years. The high figures for asthma in a region with a high level of gastrointestinal parasites infestation, a high burden of acute respiratory and gastrointestinal infections occurring early in life, severe environmental and hygiene problems, suggest that these factors, considered as protective in other (developed) regions of the world, do not have the same effect in this region. Furthermore, those aggressive environmental conditions acting together from very early in life might condition different asthmatic phenotypes with more severe clinical presentation in infancy (first 2 years of life), lower atopy and enhanced airways reactivity. The present study indicates that the prevalence of asthma and related symptoms in Latin America is as high and variable as described previously for industrialized or developed regions of the world and that the environmental risk factors, mainly related with poverty, could be responsible for the different clinical and functional presentations of asthma in children from developing regions.     

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.     

Stable prevalence of asthma symptoms in school-aged children in the Torres Strait region

Background and objective:   To (i) determine if the prevalence of asthma has altered in two previously studied communities and (ii) obtain baseline measures in two further communities in the Torres Strait region, Australia.
Methods:   A population-based cross-sectional study of school-aged children was conducted. Five schools in four communities were selected: 361 children aged 5–17 years participated. The study used the same epidemiological tool that had been utilized to measure asthma prevalence (locally adapted International Study of Asthma and Allergy in Childhood questionnaire).
Results:   The overall response rate was 30%; response rates in individual communities ranged from 23% to 100%. The prevalence of self-reported wheezing in the last 12 months decreased from 10.7% to 6.6% ( P  = 0.109) on Thursday Island and from 3.1% to zero ( P  = 0.358) on Warraber Island. The percentage of children with asthma symptoms was lower in this current study but changes were not statistically significant. Overall self-reported prevalence of ever wheezing was 12.5%; 5.4% reported wheezing in the previous 12 months, 5.9% reported wheezing after exercise and 12.2% reported ever having asthma. There was considerable inter-community variation in the prevalence of symptoms.
Conclusions:   Asthma prevalence in school-aged children living in the Torres Strait region remains high but, as in mainstream Australian children, the prevalence is stable.     

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.     

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.     

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.     

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.     

International Study of Asthma and Allergies in Childhood (ISAAC): prevalence of asthma and asthma-related symptoms among Brazilian schoolchildren.

We have studied the prevalence of asthma and its symptoms using a standard written questionnaire (WQ) designed for the International Study of Asthma and Allergies in Children (ISAAC). The WQ (questions 1 through 8 related to asthma) was applied to 13,604 children aged 6-7 years from six Brazilian cities: Porto Alegre (South, N = 2,976), Curitiba (South, N = 1,664), S?o Paulo (Southeast, N = 3,005), Uberlandia (Southeast, N = 3,002), Itabira (Southeast, N = 1,551) and Recife (Northeast, N = 1,406). At the age of 13-14 years the WQ was applied to 20,554 schoolchildren living in Porto Alegre (South, N = 3,198), Curitiba (South, N = 3,008), S?o Paulo (Southeast, N = 3,008), Uberlandia (Southeast, N = 3,001), Itabira (Southeast, N = 2,134), Salvador (Northeast, N = 3,119) and Recife (Northeast, N = 3,086). The parents of the younger children answered the WQ, whereas the adolescents answered the questionnaire themselves. The response rates were 72% and 93% for the 6-7-year-old children and for the 13-14-year-old children, respectively. There was a slight predominance of male children in the population studied. In the group of 6-7-year-olds, the prevalence of physician diagnosed asthma was 7.3% for boys and 4.9% for girls: in the group of 13-14-year-olds the rates were 9.8% and 10.2%, respectively. Asthma severity was similar for both age groups, and wheezing following exercise was more frequent among the adolescents. In keeping with studies from other parts of the world, comparison between reported symptoms and diagnosed asthma revealed a significantly lower frequency of diagnosed asthma, suggesting that in the study population, asthma is underdiagnosed.     

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.     

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.     

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.     

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.     

High prevalence of asthma in five remote indigenous communities in Australia.

Data on the prevalence of asthma in children residing in remote indigenous communities in Australia are sparse, despite the many reports of high prevalence in nonindigenous children of this country. Two previous Australian studies have had poor participation rates, limiting interpretation of their results. A study of children in the Torres Strait and Northern Peninsula Area of Australia was conducted to document the prevalence of asthma symptoms. Five indigenous communities were randomly selected and trained interviewers, who were local indigenous health workers, recruited participants using a house-by-house approach. Information was collected by a structured face-to-face interview based on a standardized questionnaire constructed from the protocol International Study of Asthma and Allergy in Childhood; 1,650 children were included in the study with a 98% response rate. Overall, the prevalence of self-reported ever wheezing was 21%; 12% reported wheezing in the previous year; and 16% reported ever having asthma. There was significant variation in the prevalence of asthma symptoms between communities. It is concluded that there are significant intercommunity variations in the prevalence of asthma symptoms in remote communities and that the prevalence in these communities is as high as in nonindigenous groups.     

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.     

Acetaminophen use and the symptoms of asthma, allergic rhinitis and eczema in children

Allergic diseases are frequent in children and their prevalence and severity differ in the different regions of the world. A number of studies have been performed to determine the factors which are effective in the incidence of these diseases. One of the drugs that might have a role in incidence or intensity of the symptoms of allergic diseases is Acetaminophen. In our survey conducted with standardized method (International Study of Asthma and Allergies in Childhood), 3000 children 6-7 years old and 3000 teenagers 13-14 years old were questioned regarding asthma, allergic rhinitis and eczema. The prevalence of ever wheezing in the children of 6-7 years old who took acetaminophen in the first year of their life was 11.3%, which is more than other group (Odds Ratio=1.54, 95% Confidence Interval: 1-2.38, P=0.049) and the prevalence of ever wheezing in older age group who have taken acetaminophen at least once in a month was 25.1% which is more than those taken less acetaminophen (OR=1.7, 95%CI=1.43-2.04, P=0.000). Moreover taking more acetaminophen during past 12 months led to more prevalence of night dry coughs and the symptoms of rhinitis in children 6-7 years old and eczema and rhinitis symptoms in the 13-14 years old. Our findings suggest that taking more acetaminophen may be associated with increasing allergic symptoms in children.     

History of ear infections and prevalence of asthma in a national sample of children aged 2 to 11 years: the Third National Health and Nutrition Examination Survey, 1988 to 1994

METHODS: We analyzed data on 7,538 children aged 2 to 11 years who participated in the Third National Health and Nutrition Examination Survey to examine the cross-sectional associations of history of ear infections with prevalence of ever-diagnosed asthma and the prevalence of wheezing in the last year in US children. RESULTS: History of ear infections was significantly related to the lifetime prevalence of diagnosed asthma (prevalence odds ratio [POR], 1.57; 95% confidence interval [CI], 1.05 to 2.36) and to the prevalence of wheezing in the last year (POR, 1.70; 95% CI, 1.22 to 2.37) after controlling for potential confounding variables. The number of ear infections was linearly and significantly related to the risk of asthma and wheezing in the last year. Among children with no diagnosis of asthma, there was a significant association between a history of ear infections and any wheezing in the last year (adjusted POR, 1.55; 95% CI, 1.07 to 2.25). CONCLUSIONS: Our study indicated strong and significant associations of a history of asthma and wheezing with the frequency of ear infections in a nationally representative sample of 7,538 children aged 2 to 11 years. These findings highlight the need for prospective studies to examine further the relationship between asthma and ear infections.     

Long-term changes in adult asthma prevalence.

There has been an increase in asthma prevalence among children. Little evidence is available regarding long-term changes in asthma prevalence in adults. Two cross-sectional studies were performed among adults aged 15-70 yrs in Oslo, Norway, in 1972 and again in 1998-1999 (n=39,998). A postal self-completed questionnaire was used. Exactly the same questions and survey methods were used in both studies. In 1998-1999, additional telephone follow-up was included for postal nonresponders. The crude prevalence of ever having had a doctor's diagnosis of asthma increased from 3.4 to 9.3%. The prevalence of wheezing increased from 17.8 to 25.8% and attacks of breathlessness from 12.6 to 16.7%. After controlling for smoking, the risk of asthma among those aged <40 yrs had tripled. The increase in asthma was 50% greater in females than males. The prevalence of symptoms increased less than asthma diagnosis. Wheezing increased by 50% in those aged <40 yrs, with smaller increases at greater ages. The increase in symptoms was seen among both asthmatics and nonasthmatics. There has been a large increase in the prevalence of asthma diagnosis and asthma-like symptoms in adults. The increase is less pronounced among those aged >40 yrs.     

Trends in the prevalence of asthma and other allergic diseases in schoolchildren from Cuernavaca, Mexico.

Several studies suggest that the prevalence of allergic diseases have increased worldwide in recent years. However, in Mexico, those diseases have not been assessed throughout time. The aim of this study was to determine whether there has been a change in the prevalence of childhood asthma, eczema, and atopic rhinitis in Mexican schoolchildren. Following the methodology recommended by the International Study of Asthma and Allergy in Childhood, we performed two cross-sectional assessments (1995/2002) using a standardized questionnaire-based survey answered by the parents of schoolchildren aged 6-8 years and 11-14 years randomly selected from schools in Cuernavaca, Mexico. The prevalence of asthma diagnosed by a doctor was 5.8% (95% CI, 5.2, 6.4) for 1995 versus 9.1% (95% CI, 8.3, 10.0) for 2002, with a greater prevalence in children aged 6-8 years in 2002 (5.7% versus 9.0%). No significant differences were found over time for wheezing in the last 12 months: 7.7% (95% CI, 7.1, 8.4) in 1995 and 8.0% (95% CI, 7.3, 8.8) in 2002. The prevalence of nasal and eye symptoms without colds was slightly higher in 1995 than it was in 2002: 9.9% (95% CI, 9.1, 10.7) versus 8.2% (95% CI, 7.4, 9.0), respectively. The results suggest an increase in the prevalence of asthma diagnosed by a doctor. However, no difference was observed in the prevalence of wheezing in the last 12 months, which may indicate a possible absence of "epidemic asthma" in the city of Cuernavaca among schoolchildren.     

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.     

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.