US childhood asthma prevalence estimates: the Impact of the 1997 National Health Interview Survey redesign

The 1997 redesign of the National Health Interview Survey (NHIS) affected US childhood asthma prevalence estimates. The 1997 asthma attack prevalence estimate for children 0-17 years was 5.4%. Pre-redesign NHIS childhood asthma period prevalence estimates peaked in 1995 at 7.5%. It is unclear whether the difference reflects the change in survey methodology or changing asthma prevalence. To examine the impact of the NHIS redesign on childhood asthma prevalence estimates, the authors analyzed the 1988 NHIS that contained two sets of asthma questions: the core survey used until 1996 and the Child Health Supplement (CHS) with questions more similar to those in the redesigned 1997 NHIS. The authors measured the difference between 1988 core and CHS childhood asthma prevalence estimates to calculate an inflation factor for 1997-2000 NHIS estimates. The 1988 CHS questions produced asthma prevalence estimates 19-34% lower than the 1988 core question, depending on the methodology used to assess the difference. Inflating the 1997 asthma attack prevalence estimate by these differences yielded modified 1997 estimates ranging from 6.5% (95% confidence interval: 5.6%, 7.5%) to 7.3% (95% confidence interval: 6.4%, 8.2%). The change in the 1997 NHIS asthma questions likely explains much of the difference in asthma prevalence estimates between 1995 and 1997.     

Measuring childhood asthma prevalence before and after the 1997 redesign of the National Health Interview Survey--United States

Asthma is the most common chronic disease of childhood and a leading cause of disability among children (1,2). Since 1980, asthma prevalence has increased dramatically in children (3,4). The National Health Interview Survey (NHIS), the principal source of asthma prevalence data for the United States, was redesigned in 1997. This report presents NHIS data from 1980-1998 to examine the effect of the redesign on measuring trends in asthma prevalence overall and among age and racial subgroups of children. The findings indicate that although asthma prevalence estimates for 1997-1998 are lower than those preceding changes in the survey design, estimates after 1997 are not comparable to previous estimates. Additional data are needed to establish a new trend after 1997.     

Prevalence of childhood allergic diseases in Adana, Southern Turkey

A study to determine the prevalence of childhood asthma and other allergic diseases was done in Adana, during the period between January 1993 and January 1994. The study has been carried out on 2334 children (48.5% boys). Asthma and the other allergic diseases were recognized in 23.6% of the children. The prevalence of asthma, rhinoconjunctivitis, wheezing, and atopic dermatitis were found to be 12.9, 8.8, 8.4, and 5.0%, respectively. The symptoms of respiratory allergic diseases (asthma, rhinoconjunctivitis, wheezing) seemed to be significantly associated with the environmental factors. In conclusion, asthma and other allergic diseases constituted a major health problem for school children in Adana.     

厦门市同安区儿童哮喘患病情况调查分析

目的 调查2012-2013年厦门市同安区0~14 岁儿童哮喘患病情况及哮喘发病的危险因素, 为今后儿童哮喘的防治工作提供科学依据。方法 通过多阶段分层随机整群抽样方法, 采用2010年第三次全国儿童哮喘流行病学调查问卷, 调查厦门市同安区10 168名0~14岁儿童哮喘患病情况;其次采用1∶1病例对照研究方法和Logistic 回归分析法对哮喘患儿的发病危险因素进行研究。结果 在调查的10 168人中, 哮喘患儿428人, 总患病率为4.21%。男性患病率(5.88%)高于女性(2.28%)(P＜0.001)。哮喘患儿中, 首次发病以3岁内居多占74.76%;发作诱因最常见的为呼吸道感染占85.61%;发作先兆最常见的为打喷嚏占95.20%;经常发作强度以轻度最常见占68.25%;发作类型以突然发作最多占78.50%;好发季节为换季占50.60%;好发时间为夜间和清晨占71.45%。通过对428例哮喘患儿及428例非哮喘儿童的病例对照研究并且经Logistic 回归分析显示, 哮喘发病的独立危险因素包括:个人过敏史、过敏性鼻炎、家族过敏史、家族哮喘史(P＜0.001)。结论 厦门市同安区0~14岁儿童哮喘患病率高于10年前厦门市区哮喘发病率。男性哮喘患病率高于女性。个人过敏史、过敏性鼻炎、家族哮喘史及家族过敏史是该地区儿童哮喘发病的独立危险因素。     

Rethinking race/ethnicity, income, and childhood asthma: racial/ethnic disparities concentrated among the very poor

OBJECTIVE: Past studies of the prevalence of childhood asthma have yielded conflicting findings as to whether racial/ethnic disparities remain after other factors, such as income, are taken into account. The objective of this study was to examine the association of race/ethnicity and family income with the prevalence of childhood asthma and to assess whether racial/ethnic disparities vary by income strata. METHODS: Cross-sectional data on 14,244 children aged <18 years old in the 1997 National Health Interview Survey were examined. The authors used logistic regression to analyze the independent and joint effects of race/ethnicity and income-to-federal poverty level (FPL) ratio, adjusting for demographic covariates. The main outcome measure was parental report of the child having ever been diagnosed with asthma. RESULTS: Bivariate analyses, based on weighted percentages, revealed that asthma was more prevalent among non-Hispanic black children (13.6%) than among non-Hispanic white children (11.2%; p<0.01), but the prevalence of asthma did not differ significantly between Hispanic children (10.1%) and non-Hispanic white children (11.2%; p=0.13). Overall, non-Hispanic black children were at higher risk for asthma than non-Hispanic white children (adjusted odds ratio [OR]=1.20; 95% confidence interval [CI] 1.03, 1.40), after adjustment for sociodemographic variables, including the ratio of annual family income to the FPL. Asthma prevalence did not differ between Hispanic children and non-Hispanic white children in adjusted analyses (adjusted OR=0.85; 95% CI 0.71, 1.02). Analyses stratified by income revealed that only among children from families with incomes less than half the FPL did non-Hispanic black children have a higher risk of asthma than non-Hispanic white children (adjusted OR=1.99; 95% CI 1.09, 3.64). No black vs. white differences existed at other income levels. Subsequent analyses of these very poor children that took into account additional potentially explanatory variables did not attenuate the higher asthma risk for very poor non-Hispanic black children relative to very poor non-Hispanic white children. CONCLUSIONS: Non-Hispanic black children were at substantially higher risk of asthma than non-Hispanic white children only among the very poor. The concentration of racial/ethnic differences only among the very poor suggests that patterns of social and environmental exposures must overshadow any hypothetical genetic risk.     

儿童哮喘相关因素分析

儿童哮喘发病率在世界范围内有不断升高的趋势,但相关病因仍然不清楚。近年来大量的流行病学研究发现,儿童哮喘危险因素包括：患儿父母有喘息及过敏史,母孕期有妊娠高血压综合征,母妊娠期间早孕反应重等：以及患儿为剖宫产,早产儿,低体重儿,自身有过敏性鼻炎,药物过敏史,湿疹,肥胖,病毒感染等因素。本研究针对以上因素对儿童哮喘进行简要论述。     

Chlorinated pool attendance, atopy, and the risk of asthma during childhood

The pool chlorine hypothesis postulates that the rise in childhood asthma in the developed world could result at least partly from the increasing exposure of children to toxic gases and aerosols contaminating the air of indoor chlorinated pools. To further assess this hypothesis, we explored the relationships between childhood asthma, atopy, and cumulated pool attendance (CPA). We studied 341 schoolchildren 10-13 years of age who attended at a variable rate the same public pool in Brussels (trichloramine in air, 0.3-0.5 mg/m3). Examination of the children included a questionnaire, an exercise-induced bronchoconstriction (EIB) test, and the measurement of exhaled nitric oxide (eNO) and total and aeroallergen-specific serum IgE. CPA by children (range, 0-1,818 hr) emerged among the most consistent predictors of asthma (doctor diagnosed or screened with the EIB test) and of elevated eNO, ranking immediately after atopy and family history of asthma or hay fever. Although the risk of elevated eNO increased with CPA [odds ratio (OR) = 1.30; 95% confidence interval (CI), 1.10-1.43] independently of total or specific serum IgE, the probability of developing asthma increased with CPA only in children with serum IgE > 100 kIU/L (OR for each 100-hr increase in CPA = 1.79; 95% CI, 1.07-2.72). All these effects were dose related and most strongly linked to pool attendance before 6-7 years of age. Use of indoor chlorinated pools especially by young children interacts with atopic status to promote the development of childhood asthma. These findings further support the hypothesis implicating pool chlorine in the rise of childhood asthma in industrialized countries.     

Infections, medication use, and the prevalence of symptoms of asthma, rhinitis, and eczema in childhood

BACKGROUND: The "hygiene hypothesis" postulates that infections during infancy may protect against asthma and atopy. There is also some evidence that antibiotic and/or paracetamol use may increase the risk of asthma. METHODS: The study measured the association between infections, and medication use early in life and the risk of asthma at age 6-7 years. It involved 1584 children who had been notified to public health services with serious infections at age 0-4 years, and 2539 children sampled from the general population. For both groups, postal questionnaires were completed by parents. RESULTS: There was little difference in the prevalence of current wheezing between the childhood infections group (prevalence = 23.5%) and the general population group (prevalence = 24.3%). There was also little difference whether the major site of infection was gastrointestinal (prevalence = 24.1%), invasive (prevalence = 24.6%) or respiratory (prevalence = 21.1%). However, in both groups, there were associations with antibiotic (OR = 1.78, 95% CI 1.49 to 2.14) or paracetamol (OR = 1.38, 95% CI 1.04 to 1.83) use in the first year of life or recent paracetamol use (OR = 2.10, 95% CI 1.78 to 2.49) and current wheezing. There was a weak protective effect of childhood infections in children who had not used antibiotics in the first year of life (OR = 0.78, 95% CI 0.55 to 1.10). CONCLUSIONS: These findings are consistent with other evidence that antibiotic use early in life may increase the risk of asthma. They are also consistent with some preliminary evidence associating paracetamol use with an increased risk of asthma. Any protective effect of notifiable childhood infections was weak.     

Ecological association between childhood asthma and availability of indoor chlorinated swimming pools in Europe

Background

It has been hypothesised that the rise in childhood asthma in the developed world could result at least in part from the increasing exposure of children to toxic chlorination products in the air of indoor swimming pools.

Objectives

Ecological study to evaluate whether this hypothesis can explain the geographical variation in the prevalence of asthma and other atopic diseases in Europe.

Methods

The relationships between the prevalences of wheezing by written or video questionnaire, of ever asthma, hay fever, rhinitis, and atopic eczema as reported by the International Study of Asthma and Allergies in Childhood (ISAAC), and the number of indoor chlorinated swimming pools per inhabitant in the studied centres were examined. Associations with geoclimatic variables, the gross domestic product (GDP) per capita, and several other lifestyle indicators were also evaluated.

Results

Among children aged 13–14 years, the prevalence of wheezing by written questionnaire, of wheezing by video questionnaire, and of ever asthma across Europe increased respectively by 3.39% (95% CI 1.96 to 4.81), 0.96% (95% CI 0.28 to 1.64), and 2.73% (95% CI 1.94 to 3.52), with an increase of one indoor chlorinated pool per 100 000 inhabitants. Similar increases were found when analysing separately centres in Western or Northern Europe and for ever asthma in Southern Europe. In children aged 6–7 years (33 centres), the prevalence of ever asthma also increased with swimming pool availability (1.47%; 95% CI 0.21 to 2.74). These consistent associations were not found with other atopic diseases and were independent of the influence of altitude, climate, and GDP per capita.

Conclusions

The prevalence of childhood asthma and availability of indoor swimming pools in Europe are linked through associations that are consistent with the hypothesis implicating pool chlorine in the rise of childhood asthma in industrialised countries.     

Prematurity as a predictor of childhood asthma among low-income children

PURPOSE: The purpose of this study was to evaluate the association among birth weight, prematurity, and the prevalence of asthma later in childhood and to assess the degree to which this association may differ between black and white children. METHODS: Michigan Medicaid claims data from 2001 through 2003 were analyzed to determine asthma prevalence for 150,204 children between ages 5 and 18 years. Asthma cases were identified using Healthcare Effectiveness Data and Information Set persistent asthma criteria and included children having claims for any of the following services within a calendar year: at least one inpatient or one emergency department (ED) claim with an asthma primary diagnosis; at least four asthma medication-dispensing events; or at least four outpatient visits with an asthma diagnosis, and at least two asthma medication-dispensing events. Birth weight and gestational age from birth certificate data were matched with Medicaid files to determine size-for-gestational-age criteria. RESULTS: Overall, 8.3% of children had persistent asthma; black children had slightly higher asthma prevalence (8.6%) than white children (7.8%; odds ratio [OR]=1.11, 95% confidence interval [CI]: 1.07-1.15). Children born very preterm (相似文献   

Risk factors for asthma in school children--results of a seven-year follow-up

The objective of the study was to evaluate the cumulative incidence of physician-diagnosed asthma over the period of 7 years, and to determine its host and environmental risk factors in children aged 7-9 years at the beginning of follow-up. The incidence of the disease was determined from answers to respiratory questionnaire on two occasions (in 1993 and 2000) in a group of 663 children aged 14-16 years in 2000. The data on host and environmental factors obtained in 1993 were used to explore predictors of asthma, by means of relative risks and the results of logistic regression analysis. The cumulative incidence of asthma (3.9%) appeared to relate to using coal for cooking/heating (RR = 2.78) and parental smoking (RR = 1.21), in addition to known effects of parental asthma (RR = 5.54), history of atopic eczema (RR = 4.66) or allergic conjunctivitis (RR = 4.11). Although the cumulative incidence of asthma increased from 2.0% in non-smoking families to 4.2% in one-parent-smoking families and 5.4% in two-parent-smoking families the results of multivariate analysis confirmed only the effects of parental asthma (logOR = 4.59), atopy (logOR = 3.88) and using coal for cooking (logOR = 3.33). The effect of exposure to parental smoking was not statistically significant (logOR = 2.33). The findings, in addition to well known host-related factors, suggest the role of environmental exposures (indoor air quality) in childhood asthma and support a challenging hypothesis concerning protective effect of measles infection--the study revealed no incidence of asthma in a group of 38 children who acquired measles before the follow-up started.     

Family history as a predictor of asthma risk

Asthma, one of the most important chronic diseases of children, disproportionately affects minority and low-income children. Many environmental risk factors for asthma have been identified, including animal, mite, and other allergens; cigarette smoke; and air pollutants. Genetics also play an important causative role, as indicated by familial aggregation and the identification of candidate genes and chromosomal regions linked to asthma risk. Using a positive family history of asthma to identify children at increased risk could provide a basis for targeted prevention efforts, aimed at reducing exposure to environmental risk factors.To assess the predictive value of family history as an indicator of risk for childhood asthma, we reviewed population-based studies that evaluated family history of asthma and atopic disease in children with asthma.Our search identified 33 studies from all geographic regions of the world for review. The studies varied in definitions of positive family history and asthma phenotype and used study populations with asthma prevalence ranging from 2% to 26%. Nevertheless, family history of asthma in one or more first-degree relatives was consistently identified as a risk factor for asthma. In ten studies, sensitivity and predictive value of a positive family history of asthma could be calculated: sensitivity ranged from 4% to 43%, positive predictive value from 11% to 37%, and negative predictive value from 86% to 97%.Although a positive family history predicts an increased risk of asthma, it identifies a minority of children at risk. Positive family history may have utility in targeting some individual prevention efforts, but the low positive predictive value limits its value as a means to direct environmental remediation efforts.     

苏州市0~14岁儿童哮喘患病率及防治现状的调查

【目的】 了解苏州市儿童哮喘患病率、起病年龄、发病诱因及防治现状,为进一步制定儿童哮喘防治措施提供科学依据。 【方法】 采用整群抽样调查,分两步:第一步问卷筛查得到疑似哮喘儿童资料,第二步对疑似病例进行临床确诊,同时了解其发病诱因及防治情况。 【结果】 收回初筛问卷10 805份,筛出喘息相关儿童622例,经临床确诊哮喘540例,咳嗽变异性哮喘5例,可疑哮喘77例。哮喘累计患病率为5%,男女患病率分别为6.22%、3.51%。过敏性鼻炎1 130例,患病率为10.46%,男女患病率分别为12.37%、8.13%。湿疹884例,患病率为8.18%,男女患病率分别为8.85%、7.35%。哮喘在3岁以内起病占77.17%。98.23%哮喘儿童反复应用过抗生素,59.97%在急性发作期接受吸入治疗,但在缓解期进行维持治疗的仅为8.89%。 【结论】 2010年苏州市0~14岁儿童哮喘累计患病率为5%,较10年前有增加,男性高于女性。儿童哮喘起病年龄大多数在3岁以内,发病高峰在春秋换季时,上呼吸道感染为最常见诱发因素。大多数哮喘患儿治疗不规范,正确、合理、规范治疗儿童哮喘的新知识、新药物要宣传、普及。     

云南省两城区儿童哮喘患病情况及其危险因素分析

目的 了解云南省城区儿童哮喘的流行现状、危险因素及其治疗情况,为进一步规范儿童哮喘的诊治及预防提供依据。方法 采用随机整群抽样的方法,通过自填式问卷调查与集中调查相结合的方式进行调查。对于初筛问卷中的可疑哮喘患儿按哮喘诊断标准进行诊断,对确诊的哮喘患儿填写哮喘儿童调查表。建立问卷数据库,并对数据进行整理、分析。结果 云南省两城区0~14岁儿童哮喘患病率为1.24%。哮喘患儿中既往诊断为哮喘及咳嗽变异性哮喘的为66.37%。哮喘患儿中使用抗生素治疗的有69.64%,使用支气管舒张剂治疗的有54.76%,吸入激素治疗有60.71%。家族过敏史、早产、房屋装修、烟草烟雾暴露等因素为哮喘发病的独立危险因素。结论 云南省城区0~14岁儿童哮喘患病率较10年前有明显增加。仍需进一步规范哮喘患儿诊治方法。预防早产、减少室内外污染、及时治疗变应性疾病及预防呼吸道感染是减少哮喘患病和预防哮喘发作的有效方法。     

Household exposure factors,asthma, and school absenteeism in a predominantly Hispanic community

The Passaic Asthma Reduction Effort (PARE) used an asthma symptom and household exposure factor questionnaire to screen 4634 elementary school children over a 4-year period in Passaic, New Jersey. During the first year, an additional 240 preschool children were also screened. Overall, 16% of the school children were reported by their parents to have been diagnosed with asthma. In all, 30% of responding families claimed to have at least one family member diagnosed with asthma and this was five times more likely if the target child had asthma. Exposures consistently associated with childhood asthma diagnosis included environmental tobacco smoke (ETS), presence of dampness/mold, roaches, and furry pets in the home. Diagnosis of asthma was primarily associated with all six symptoms used in the PARE questionnaire, and secondarily with environmental factors. Puerto Rican and black children had the highest asthma prevalence (26% and 33%), while Mexican children had the lowest (7%). Use of medications and school absenteeism among asthmatic children were associated with wheeze and night cough, but not with any specific environmental exposure. Increased school absenteeism by children undiagnosed with asthma was associated with ETS and dampness/mold in the home. Differences in asthma diagnosis and absenteeism in response to environmental factors were found across ethnic subgroups. Getting asthmatic children on medical management protocols and providing families with education about environmental risk reduction should aid in reducing morbidity in this ethnically complex population. Such coordinated efforts offer the promise of reducing school absenteeism.     

Trends in adolescent asthma in Israel

There has been observed a worldwide increase in childhood asthma and this short communication reviews current research on adolescent asthma in Israel. Several studies have found an overall asthma prevalence of 7.8% for Jewish children, 4.9% for Arab children and 3.7% for the total population, while 7.8% was found in Bedouin children in the south of Israel. For the 1980-1997 period for the 5-34 year age group the AMR (asthma mortality rate) per 100,000 was found to be 0.226 with no significant difference between Jews and Arabs. This is a decrease as a result of increase in the use of inhaled corticosteroids (ICS) and a better anti-inflammatory treatment.     

Asthma and farm exposures in a cohort of rural Iowa children

Epidemiologic studies of farm children are of international interest because farm children are less often atopic, have less allergic disease, and often have less asthma than do nonfarm children--findings consistent with the hygiene hypothesis. We studied a cohort of rural Iowa children to determine the association between farm and other environmental risk factors with four asthma outcomes: doctor-diagnosed asthma, doctor-diagnosed asthma/medication for wheeze, current wheeze, and cough with exercise. Doctor-diagnosed asthma prevalence was 12%, but at least one of these four health outcomes was found in more than a third of the cohort. Multivariable models of the four health outcomes found independent associations between male sex (three asthma outcomes), age (three asthma outcomes), a personal history of allergies (four asthma outcomes), family history of allergic disease (two asthma outcomes), premature birth (one asthma outcome), early respiratory infection (three asthma outcomes), high-risk birth (two asthma outcomes), and farm exposure to raising swine and adding antibiotics to feed (two asthma outcomes). The high prevalence of rural childhood asthma and asthma symptoms underscores the need for asthma screening programs and improved asthma diagnosis and treatment. The high prevalence of asthma health outcomes among farm children living on farms that raise swine (44.1%, p = 0.01) and raise swine and add antibiotics to feed (55.8%, p = 0.013), despite lower rates of atopy and personal histories of allergy, suggests the need for awareness and prevention measures and more population-based studies to further assess environmental and genetic determinants of asthma among farm children.     

The associations between childhood asthma and atopy, and parental asthma, hay fever and smoking

Summary. The aim of this analysis was to examine the degree to which a life time prevalence of asthma in a 7-year-old child is statistically associated with atopic conditions of the child, and with parental asthma, hay fever and smoking. In 1968, 8585 children who were born in 1961 and who were attending school in Tasmania were surveyed. This comprised 99% of the eligible population. The prevalence of a history of asthma in the 7-year-olds was 16.2% (males 19.0%, females 13.2%). Multiple logistic regression analysis showed that a history of asthma in a 7-year-old was associated with the child being male (odds ratio [OR] 1.56; 99% confidence interval 1.30–1.86), having a history of hay fever (3.86; 3.12–4.78), eczema (2.04; 1.63–2.55), hives (1.34; 1.09–1.65) or allergy to foods or medicines (1.70; 1.26–2.30), the child's mother or father having a history of asthma (2.63; 2.08–3.31 or 2.52; 1.99–3.19, respectively), and the mother being a smoker (1.26; 1.05–1.51). Parental hay fever and paternal smoking were not independently associated with childhood asthma. The strength of association between childhood asthma and parental asthma was independent of the sex of either the parent or the child, and of atopic conditions in the child. In the 133 children for whom both parents were asthmatic, 65 (49%) had a history of asthma. These findings, based on a population survey, are consistent, not only with a childhood history of asthma being strongly associated with atopy, but also with the existence of strong unmeasured determinants common to family members, the effects of which are not mediated via atopy. The risk for asthma being independent of both the sex of the child and of the parent, is consistent with a genetic aetiology for susceptibility to asthma.     

Increase in prevalence of childhood asthma in Budapest between 1995 and 2003: correlation with air pollution data and total pollen count

INTRODUCTION: According to the data of the Hungarian pulmonological network, the prevalence of asthma in the last 15 years has increased (almost linearly) in Hungary. In 2004 it was 1.8%. There are only a few data about the prevalence of childhood asthma. AIMS: The aim of the authors was to measure the prevalence of bronchial asthma in childhood in Budapest in 1995, 1999 and 2003, using questionnaires directed to district pediatricians. METHODS: There were only two questions in these questionnaires: how many children are in their districts, and how many are suffering from asthma? Besides of this survey the dust, CO, NO(2) and SO(2) concentrations in the air were measured on-line at 8 points in Budapest, while ozone level measurements were also made at 2 stations. The counts of pollen and of fungal elements in the air were calculated separately for Buda and for Pest. RESULTS: In 1995, replies were received from 118 pediatricians in 11 districts, who were responsible for the supervision of 104,060 children, out of these 1.88+/-0.87% had been diagnosed as having asthma. In 1999 replies were sent by 153 physicians in 22 of the 23 districts, who had a total of 142,679 children under their care. These included 3228 asthmatics, i.e. a prevalence of 2.26+/-0.95%. In 2003 the authors received answers from all of the 23 districts of Budapest. The 204 pediatricians were responsible for the supervision of 176 049 children. The number of patients with the diagnosis of asthma was 4712 (corresponding for a prevalence of 2.68+/-1.3%). The increase between 1995 and 1999, and between 1999 and 2003 was highly significant (p < 0.0001). This significant increase was valid even when the authors analysed only those 11 districts, which answered already in 1995. The level of air pollution in Budapest did not deteriorate in the period in question, and the concentration of pollen grains of plants causing allergy did not increase compared to previous years. CONCLUSIONS: On the basis of the results of more than 100 thousand children, the authors conclude that between 1995 and 2003 the proportion of asthmatic children increased by 50% in Budapest, while the air pollution did not deteriorate and the pollen concentration from sensitizing plants did not increase.