A decrease in the prevalence and improved control of allergic conditions in 13- to 15-yr-old Maltese children (ISAAC)

Abstract

The International Study of Asthma and Allergies in Childhood (ISAAC) has produced a reliable global map of childhood allergies through the use of a validated standardized questionnaire. Phase 1 of the study was carried out in the Maltese Islands in 1995 and repeated in 2002 in phase 3. To investigate the trends in prevalence and severity of childhood allergies in Maltese schoolchildren, in this article, we compare the data obtained from 4184 children, 13- to 15-yr-olds (88.7% response rate) in phase 1, to that of phase 3 when 4139 (90% response rate) children participated. The cumulative (27.9% vs. 27.4%: p = 0.6) and current (16% vs. 14.6% p = 0.08) prevalence rates of wheezing remained quite static but wheezers were more likely to be diagnosed with asthma in 2002 (11.1% vs. 14.1% p < 0.0001). Along the 7 yrs, these asthmatics were better controlled with less wheezing attacks (p < 0.01), less disturbed nights (p < 0.05) and less acute severe episodes (p < 0.05). Nasal problems were present in 52.7% of participants in 1995 and in 50.4% in 2002 (p < 0.05), and 47.4% vs. 42.8% (p < 0.0001) persisted with these symptoms and associated itchy eyes (29% vs. 21.8%: p < 000001). Though prevalence decreased, the children were labelled as hayfever sufferers more often (32.3 vs. 40.7%: p < 0.00001). Rhinitis symptoms seemed to interfere less with daily activities (p < 0.01). In 2002, an itchy rash suggestive of eczema was also less present ‘ever’ (12.8% vs. 11.2%: p < 0.05) or currently (10.1% vs. 8.5%: p < 0.05) but again more likely to be diagnosed as eczema (p < 0.001). This rash caused less sleepless nights in phase 3 of the study (p < 0.05). These results indicate that asthma prevalence has reached a plateau between 1995 and 2002 while rhinitis and eczema are less common. All these allergic conditions are better controlled and more likely to be diagnosed in these schoolchildren by Maltese doctors in 2002 than in 1995.