Allergic disorders and socio-economic status: a study of schoolchildren in an urban area of Makassar, Indonesia

Abstract

Background: In urban centres of developing countries, there is great variation in socio-economic status (SES) and lifestyle; however, little information is available on allergic disorders in groups with high- or low-SES within the same urban area.

Objective: To determine the prevalence of allergic disorders and investigate risk factors related to them among high- and low-SES schoolchildren in Makassar, the capital city of South Sulawesi, Indonesia.

Method: This cross-sectional study was performed in 623 children originating from high- (N = 349) and low-SES (N = 274) schools. Information on reported allergic symptoms and potential factors associated with allergic disorders was obtained by questionnaire. Specific IgE and skin prick test (SPT) reactivity were determined against aeroallergens [Dermatophagoides pteronyssinus (HDM) and cockroach]. Total IgE and helminth infections were also assessed.

Result: The prevalence of SPT to any aeroallergens was significantly higher in high-SES than in low-SES school (25% vs. 8%, P < 0.001, respectively). However, specific IgE against cockroach and total IgE were significantly lower in high- than in low-SES children. Allergic symptoms were reported more often in low- compared to high-SES children. Specific IgE to aeroallergens significantly increased the risk of SPT positivity to the same aeroallergen in the high-, but not in the low-SES children. In the high- but not in low-SES, there was a significant positive association between SPT to HDM and wheeze. Similarly, cockroach skin reactivity and elevated BMI increased the risk of eczema in the high-SES children only.

Conclusion and clinical relevance: Skin prick test is higher in high-SES, whereas IgE and allergic symptoms are higher in low-SES children. Specific IgE is a risk factor for being SPT-positive, and SPT positivity is a risk factor for allergic symptoms but only in children of high- and not low-SES school. Therefore, the socio-economic status of a child might affect the diagnosis of allergic disease in a developing country.

Keywords: IgE; allergy; atopy; helminths; risk factors; socio-economic status.