Temporal trends in the prevalence of asthma and rhinoconjunctivitis in adolescents

Geographic pattern of asthma prevalence in Brazilian adolescents: a systematic review with meta-analysis

OBJECTIVES

This study aimed to verify the prevalence of asthma in Brazilian adolescents and its geographic pattern carried through a systematic review and meta-analysis.

SOURCES

A survey of databases (Pubmed, Chocrane, LILACS, SCIELO and SCOPUS) was carried out, following the PRISMA statement, between the years 2013 and 2023 (PROSPERO-ID-CRD42023427988). Articles that presented a measure relative to the prevalence of asthma in adolescents were included. The methodological quality regarding risk of bias was assessed according to the approach proposed by the Joanna Brigg Institute.

SUMMARY OF THE FINDINGS

Ten of a total of 3140 studies were included. Six studies were collected before 2015. The prevalence of active asthma, severe asthma, and diagnosed asthma were 18 %, 6 %, and 14 %, respectively. The studies were presented in large urban centers and capitals, had a high methodological quality, and showed high heterogeneity. Subgroup analysis was carried out, separating the cities according to the different regions of Brazil (north, northeast, center-west, south, and southeast). The northeast was the region with the lowest prevalence of active asthma (14 %, 95 % CI = 12-17 %, p < 0.001). There was no difference between regions in terms of diagnosed asthma and severity.

CONCLUSION

A high proportion of Brazilian adolescents reported having active asthma, with the northeast region having the lowest prevalence. Most of the studies were collected more than eight years ago and regard capitals and large urban centers. The high heterogeneity found demonstrates uncertainty in asthma prevalence in Brazil and highlights the need for clearer protocols addressing the multifactorial nature of the disease.

Body mass index, asthma, and respiratory symptoms: a population-based study

Objective:

To estimate the prevalence of respiratory symptoms and asthma, according to body mass index (BMI), as well as to evaluate factors associated with physician-diagnosed asthma, in individuals ≥ 40 years of age.

Methods:

This was a population-based cross-sectional study conducted in Florianópolis, Brazil, with probability sampling. Data were collected during home visits. Demographic data were collected, as were reports of physician-diagnosed asthma, respiratory symptoms, medications in use, and comorbidities. Anthropometric measurements were taken. Individuals also underwent spirometry before and after bronchodilator administration. Individuals were categorized as being of normal weight (BMI < 25 kg/m²), overweight (25 kg/m² ≥ BMI < 30 kg/m²), or obese (BMI ≥ 30 kg/m²).

Results:

A total of 1,026 individuals were evaluated, 274 (26.7%) were of normal weight, 436 (42.5%) were overweight, and 316 (30.8%) were obese. The prevalence of physician-diagnosed asthma was 11.0%. The prevalence of obesity was higher in women (p = 0.03), as it was in respondents with ≤ 4 years of schooling (p < 0.001) or a family income of 3-10 times the national minimum wage. Physician-diagnosed asthma was more common among obese individuals than among those who were overweight and those of normal weight (16.1%, 9.9%, and 8.0%, respectively; p = 0.04), as were dyspnea (35.5%, 22.5%, and 17.9%, respectively; p < 0.001) and wheezing in the last year (25.6%, 11.9%, and 14.6%, respectively; p < 0.001). These results were independent of patient smoking status. In addition, obese individuals were three times more likely to report physician-diagnosed asthma than were those of normal weight (p = 0.005).

Conclusions:

A report of physician-diagnosed asthma showed a significant association with being ≥ 40 years of age and with having a BMI ≥ 30 kg/m². Being obese tripled the chance of physician-diagnosed asthma.

Is allergic rhinitis related to migraine disability in adults?

OBJECTIVE

Migraine is a chronic condition with complex pathophysiology. Although immunologic disturbances have been linked to migraine, only few attempts have been made to assess the possibility of allergic rhinitis as a worsening factor of migraine in adults. This survey aimed to compare migraine disability between adult migraineurs with and without current allergic rhinitis.

METHODS

This cross-sectional study comprised 118 adult migraineurs who were consecutively assisted at an outpatient clinic. After ordinary neurological evaluation, participants were evaluated for headache disability using the Migraine Disability Assessment (MIDAS). The presence of current allergic rhinitis, allergic rhinoconjunctivitis and seasonal allergic rhinitis was scored for each participant according to the International Study of Asthma and Allergies in questionnaire.

RESULTS

There was no significant difference between the MIDAS scores of those with current allergic rhinitis, allergic rhinoconjunctivitis, or seasonal allergic rhinitis and nonatopic migraineurs. The disability caused by allergic symptoms also did not influence the MIDAS scores of patients with allergic rhinitis. The frequency of headache days during the last three months was higher in the subset of patients without allergic rhinitis (median and interquartile range 12 [8-19.2] vs. 8 [4-14]; p = 0.03).

CONCLUSIONS

Our results suggest that current allergic rhinitis, allergic rhinoconjunctivitis, and seasonal allergic rhinitis are not related to headache disability in adults with episodic migraine.

The Trend of Change of Allergic Diseases over the Years: Three Repeated Surveys from 1994 to 2014

BACKGROUND

Although it is known that there has been an increase in asthma and allergic diseases among school-aged children, results vary between countries. The aim of this study was to examine trends in the prevalence of these diseases in the city of Adana (south Turkey) over the last 20 years based on the results of 3 cross-sectional studies.

METHODS

Three cross-sectional surveys were performed 10 years apart in south Turkey. Here, we compare the surveys conducted among children between the ages of 6 and 14 years from 1994, 2004, and 2014. The participants were randomly chosen among children attending participating primary schools in Adana. The questionnaire in the first survey contained almost the same questions as the ISAAC. In the 2 latter surveys, we used the ISAAC questionnaire to investigate the prevalence of asthma and other allergic diseases.

RESULTS

A total of 2,334 children in 1994, 3,728 children in 2004, and 3,209 children in 2014 were included in the final analysis. The results showed a statistically significant increase in the prevalence of physician-diagnosed allergic diseases across the years, respectively: asthma (5, 4.6, and 8.9%), allergic rhinitis (8.8, 11.4, and 15.6%), and atopic dermatitis (5, 9.9, and 7%). In contrast, the prevalence of parent-reported current wheeze (16.2, 13.2%) decreased in the last 10 years.

CONCLUSIONS

Our findings were consistent with the increased prevalence of childhood asthma and other allergic diseases. However, this pattern did not occur in respiratory symptoms.

Changes in symptoms of asthma and rhinitis by sensitization status over ten years in a cohort of young Chilean adults

Background

We investigated the net changes in prevalence of symptoms of asthma and rhinitis over 10 years in a cohort of young by baseline sensitization status.

Methods

One thousand one hundred ninety three Chilean adults subjects aged 22–28 living in a semi-rural area of central Chile answered a lifestyle and the European Community Respiratory Health Survey (ECRHS) questionnaires. Bronchial hyper-responsiveness (BHR) and skin prick test (SPT) to eight allergens were measured at baseline in 2001. Ten years later, 772 participants completed the questionnaires again. Estimates of adjusted net changes in prevalence of symptoms by sensitization status at baseline and association between sensitization status at baseline and respiratory symptoms ten years later were assessed.

Results

A quarter of the participants were sensitized to at least one allergen in 2001. Prevalence of wheeze had a net change per year of −0.37 % (95 % Confidence Interval −0.71 to 0.02 %; p = 0.067). Self-reported nasal allergies in the last 12 months increased by 0.83 % per year (95 % CI 0.49 to 1.17 %; p < 0.001). Those sensitized to either cat fur (OR 1.76; CI 1.01 to 3.05), cockroach, (OR 2.09; 1.13 to 3.86) blend of grass and pollens (1.78; 95 % CI 1.08 to 2.92), or weeds (OR 1.77; 95 % CI 1.01 to 3.12) in 2001 were more likely to have wheeze in the last 12 months 10 years later.

Conclusion

Symptoms of asthma remained stable or slightly changed over 10 years in adults, whilst rhinitis and nasal allergies greatly increased. Being sensitized to at least one allergen is a risk factor for persistent symptoms of asthma and rhinitis, but not for determining net changes of symptoms over time. The underlying causes for the contrasting trends between asthma and nasal allergy are unknown.

Electronic supplementary material

The online version of this article (doi:10.1186/s12890-016-0273-6) contains supplementary material, which is available to authorized users.