Internal migration and its association with childhood asthma in Ecuador: a cross-sectional study.

BACKGROUND

Differences in asthma prevalence between urban and rural areas have been observed worldwide. Epidemiological studies in middle- and low-income countries suggest that internal migration processes may partly explain these disparities.

OBJECTIVE

To investigate the association between internal migration and asthma in children living in transitional areas of Ecuador.

METHODS

A cross-sectional study was conducted using data from a birth cohort of children living in a tropical coastal region in northwestern Ecuador. Asthma indicators included wheezing in the past 12 months, ever wheezing, and asthma diagnosis by a doctor. Internal migration was defined as a change of residence between geographical units: cantonal, parish, and census tract. The relationship between asthma and migration was analyzed using binary logistic regression.

RESULTS

Of 2,404 participants, 1,818 children met the inclusion criteria. Among them, 2.8% experienced cantonal migration, 11.9% parish migration, and 24.6% census tract migration. The prevalence of wheezing in the past 12 months, ever wheezing, and asthma diagnosis by a doctor was 13.1%, 33.3%, and 7%, respectively. Children with a history of cantonal migration were more likely to have experienced wheezing compared to those who did not migrate (OR: 1.56; 95%CI: 0.87-2.79).

CONCLUSIONS

Changes in residence between smaller or adjacent geographic units appeared not to be associated with asthma prevalence. However, cantonal migration may play a role in respiratory health outcomes.