Asthma co-morbidities in Nigerian children: prevalence, risk factors and association with disease severity and symptoms control

INTRODUCTION: Prompt recognition and management of co-morbidities is an important step in ensuring optimal childhood asthma symptoms control. This study sets out to determine the prevalence, predictive factors and association of co-morbidities with asthma severity, lung functions and symptoms control in Nigerian children. METHODS: Children (aged 2 to 15 years) with physician-diagnosed asthma at the Wesley Guild Hospital, Nigeria were consecutively recruited. Asthma co-morbidities, severity and levels of symptoms control were assessed using standard definitions. Lung functions of children ≥ 6 years were also measured. Factors predictive of asthma co-morbidities and association of co-morbid conditions with asthma severity, lung functions and symptoms control were determined using univariate and multivariate analyses. RESULTS: A total of 186 children (male: female 1.4:1) were recruited and the majority (81.0%) had mild intermittent asthma. Forty (21.5%) had suboptimal symptoms control and 112 (60.2%) had associated co-morbidities. Allergic rhinitis and/or conjunctivitis (41.4%) were the most common co-morbidities. Predictors of concomitant presence of allergic rhinitis among the children were older age group ≥ 6 years (OR = 2.488; 95%CI 1.250-4.954; p = 0.036) and lack of exclusive breastfeeding (OR = 2.688; 95%CI 1.199 -5.872; p = 0.020) while obesity/overweight (OR = 6.300; 95%CI 2.040-8.520; p = 0.003) and Allergic rhinitis (OR = 2.414; 95%CI 1.188-6.996; p = 0.049) were determinants of persistent asthma. Suboptimal symptoms control was associated with having concomitant allergic rhinitis (p = 0.018), however no comorbid condition predicted lung function impairment. CONCLUSION: About two-thirds of children with asthma had co-morbidities and allergic rhino-conjunctivitis was the most common. School age group and early introduction to breast milk substitutes predict the presence of these co-morbidities which also affect asthma severity and control.