Objective: To analyze the bidirectional association between wheezing and obesity during adolescence and the beginning of adulthood in a cohort in southern Brazil. Methods: This prospective longitudinal study used data from the 1993 birth cohort in Pelotas, Brazil. The following outcome variables were measured at 22 years of age: self-reported wheezing during the last 12 months and obesity (BMI = 30 kg/m2). The following exposure variables were measured at ages 11, 15, and 18: self-reported wheezing (no wheezing or symptom presentation in 1, 2, or 3 follow-ups) and obesity (non-obese or obese in 1, 2, or 3 follow-ups). Crude and adjusted logistical regression stratified by sex were used in the analyses. The reference category was defined as participants who presented no wheezing or obesity. Results: A total of 3,461 participants had data on wheezing and 3,383 on BMI. At 22 years of age, the prevalence of wheezing was 10.1% (95%CI: 9.1; 11.2), and obesity, 16.2% (95%CI: 15.0; 17.6). In females, the presence of wheezing in two follow-ups revealed a 2.22-fold (95%CI: 1.36; 3.61) greater chance of developing obesity at 22 years of age. Meanwhile, the presence of obesity in two follow-ups resulted in a 2.03-fold (95%IC: 1.05; 3.92) greater chance of wheezing at 22 years of age. No associations were found between wheezing and obesity in males. Conclusions: The obtained data suggest a possible positive bidirectional association between wheezing and obesity, with greater odds ratios in the wheezing to obesity direction in females and in the category of occurrence of exposure in two follow-ups.

Keywords: Asthma, BMI, Respiratory Sounds, Wheezing, Body Weight.

Objective: To study the prevalence of wheezing patterns and their associations with independent variables. Methods: Cohort study of live births in 1993 in Pelotas, Brazil. A systematic subsample (20%) of the original cohort was evaluated at 6 months, 12 months and 4 years. At 10-12 years, 87.5% of the original cohort was contacted. Wheezing was categorized: transient, wheezing at 4 years but not at 10-12; persistent, wheezing at all evaluations; late-onset, wheezing at 10-12 years. Independent variables were analyzed: gender; skin color; family income; smoking/asthma during pregnancy; breastfeeding; respiratory infection/diarrhea (during the 1st year); family members with asthma/ allergy (at 4 years and at 10-12); physician-diagnosed rhinitis/eczema (at 10-12 years). Results: The subsample comprised 897 adolescents. Wheezing patterns were expressed as prevalence (95% CI): transient, 43.9% (40.7-47.2); persistent, 6.4% (4.8-8.0); and late-onset, 3.3% (2.2-4.5). The transient pattern was more common in children from low-income families, children breastfed for less time, children with a history of respiratory infections (during the 1st year) and children with asthma in the family (at 4 years). The persistent pattern was almost twice as common in males, in children whose mothers had asthma during pregnancy, in children with respiratory infections (during the 1st year) and in children with asthma in the family (at 4 and 10-12 years). The late-onset pattern was more prevalent among those with asthma in the family (at 10-12 years) and those diagnosed with rhinitis (at 10-12 years), being less prevalent among those reporting respiratory infections (during the 1st year) and those diagnosed with eczema (at 10-12 years). Conclusions: Knowledge of the associations of wheezing patterns allows us to adopt preventive and therapeutic measures.

Keywords: Respiratory sounds; Asthma; Epidemiology; Hypersensitivity.

To evaluate the characteristics of users of inhalers and the frequency of inhaler use among adolescents and adults with self-reported physician-diagnosed asthma, bronchitis, or emphysema. Methods: A population-based study conducted in the city of Pelotas, Brazil, involving 3,670 subjects ≥ 10 years of age, evaluated with a questionnaire. Results: Approximately 10% of the sample reported at least one of the respiratory diseases studied. Among those individuals, 59% reported respiratory symptoms in the last year, and, of those, only half reported using inhalers. The use of inhalers differed significantly by socioeconomic status (39% and 61% for the lowest and the highest, respectively, p = 0.01). The frequency of inhaler use did not differ by gender or age. Among the individuals reporting emphysema and inhaler use, the use of the bronchodilator-corticosteroid combination was more common than was that of a bronchodilator alone. Only among the individuals reporting physician-diagnosed asthma and current symptoms was the proportion of inhaler users higher than 50%. Conclusions: In our sample, inhalers were underutilized, and the type of medication used by the individuals who reported emphysema does not seem to be in accordance with the consensus recommendations.

Keywords: Metered dose inhalers; Asthma; Pulmonary disease, chronic obstructive; Bronchitis; Emphysema; Dry powder inhalers.