Asma e obesidade durante a infância até o início da vida adulta: Uma análise bidirecional na coorte de nascimentos de 1993, Pelotas, Brasil

Abstract

Asthma is a chronic disease characterized by respiratory tract inflammation and respiratory symptoms that modify on intensity and frequency over the time. The most common respiratory symptom is wheezing. In the last years, the literature shows a possible positive association between wheezing and obesity. Obesity is a chronic multifactorial non-communicable disease that is considered as a global public health problem due the prevalence increases around the world since the last decades. Asthmatic obese individuals have a worse diseases control and this affect the quality of life and limiting daily activities. However, the relationship between the two conditions is not yet clear. This thesis aimed to explore the association between asthma (measured by wheezing) and obesity, by data collected from childhood to early adulthood in the 1993 Pelotas birth cohort. Wheezing and obesity trajectories and the bidirectional association between the two conditions were the focus on the investigation. Three papers were performed about these thematic. The first paper aimed to analyze the bidirectional association during adolescence and early adulthood (from 11 to 22 years of age) and considered a cumulative effect of exposures. A positive bidirectional association between wheezing and obesity was observed specifically in females. Women who self-reported wheezing in two follow-ups between the ages of 11 and 18, presented a greater chance to be classified as obese at age 22 and, and opposite, women who were classified as obese in two follow-ups presented a greater chance of developing wheezing at the age 22. The second paper included a longitudinal analysis that proposed to identify the wheezing and obesity trajectories and verify the bidirectional association from 4 to 22 years of age. Four wheezing trajectories groups and four obesity trajectories groups were identified. A positive bidirectional association between the two condition was observed too, only in females. High obesity prevalence with a slight increase trajectory was associated with wheezing at 22 years and early transient wheezing and persistent wheezing trajectories were associated with obesity at 22 years of age. The last paper aimed to describe the pulmonary function in early adulthood according to the wheezing and obesity trajectories. We observed that the average of forced expiratory volume in the first second (FEV1), the forced vital capacity (FVC) and the FEV1/FVC, at 22 and 30 years of age, were lower in individuals with trajectories of exposure to the wheezing compared with trajectories of never/infrequent wheezing. On the other hand, the obesity trajectories did not show statistically significant changes in the mean of pulmonary function in early adulthood.