Prevalence, symptomatology and factors associated with asthma in adolescents aged 13-14 years from rural Sri Lanka: an analytical cross-sectional study.

Background: Asthma is the most common chronic disease affecting children. However, the epidemiology of asthma in adolescents from rural geographies is lacking.

Methods: An analytical cross-sectional study was conducted in secondary schools located in the municipal council area of the rural district of Anuradhapura, Sri Lanka. Random sampling was used to select 32 grade 8 classes from 6 out of 9 schools. The prevalence and symptomatology of asthma were determined using the validated International Study of Asthma and Allergy in Childhood (ISAAC) questionnaire and asthma symptom control using the asthma control test (ACT) translated into Sinhalese.

Results: The study sample consisted of 1029 participants aged 13-14 years, including 528 (51.3%) boys and 501 (48.7%) girls. The prevalence of wheeze ever, current wheeze and wheeze while playing was 32.6% (n=335), 23.7% (n=244) and 25.2% (n=259), respectively. The prevalence of parent-reported physician-diagnosed asthma was 19.0% (n=196; 95% CI 16.7 to 21.6). Severe asthma was reported by 157 (15.3%; 95% CI 13.1 to 17.6) adolescents. The independent factors associated with severe asthma were sleeping on a cloth laid on the floor instead of a bed (p<0.02, adjusted-OR 9.72; 95% CI 1.56 to 60.78), cooking using sawdust (p=0.04, adjusted-OR 8.71; 95% CI 1.10 to 68.69) eczema (p<0.01; adjusted-OR 7.39; 95% CI 3.34 to 16.39) and allergic rhinitis (p<0.01; adjusted-OR 5.50; 95% CI 3.80 to 7.98). While having a cemented floor in the house (p<0.04; adjusted-OR 0.68; 95% CI 0.47 to 0.99) was a protective factor. Poor control of asthma symptoms was detected in 29 (29.9%) adolescents which was associated with comorbid allergic rhinitis (p<0.01; unadjusted-OR 5.40; 95% CI 1.84 to 15.82).

Conclusion: Almost one in four adolescents had current wheeze, and 15.3% had severe asthma. Severe asthma was independently associated with allergic rhinitis, eczema, cooking using sawdust as fuel and sleeping on a cloth on the floor instead of a bed. Poor symptom control was found in 29.9% of severe asthmatics which was associated with comorbid allergic rhinitis.