Prevalence trends of rhinoconjunctivitis, eczema, and atopic asthma in Greek schoolchildren: four surveys during 1991-2008

After a continuous increase of asthma, hay fever, and eczema during 1991-2003 among schoolchildren in Patras, Greece, the prevalence of current wheeze/asthma (diagnosed wheezing and/or asthma in the past 2 years) has reached a plateau (6.9%) during the period 2004-2008. Using methodology identical to the three previously conducted cross-sectional, parental questionnaire surveys (1991, n = 2417; 1998, n = 3076; 2003, n = 2725) we examined further trends in the prevalence of rhinoconjunctivitis and eczema in the same urban environment among third and fourth grade schoolchildren (8-9 years old) in 2008 (n = 2688). In the four surveys, respective prevalence rates of rhinoconjunctivitis were 2.1, 3.4, 4.6, and 5.1% (absolute prevalence increase: 1998 versus 1991, 61.9%; 2003 versus 1998, 35.5%; 2008 versus 2003, 10.9%) and those of eczema were 4.5, 6.3, 9.5, and 10.8% (absolute prevalence increase: 1998 versus 1991, 40.0%; 2003 versus 1998, 50.8%; 2008 versus 2003, 13.7%; sex-adjusted p for trend, <0.001). Among current wheezer/asthmatic patients there was an increase in lifetime rhinoconjunctivitis (sex-adjusted p for trend, <0.001) and lifetime eczema (sex-adjusted p for tend, <0.001) over the period 1991-2008. The proportion of atopic wheeze/asthma (current asthma with lifetime rhinoconjunctivitis and/or eczema) increased further during 2003-2008 (p < 0.05; p for trend during 1991-2008, <0.001). In conclusion, there is a continuous increase in the prevalence of allergic manifestations-rhinoconjunctivitis and eczema-among preadolescent children in Patras, Greece, during the period 1991-2008. After a steep rise during 1991-2003, the frequency of atopic wheeze/asthma continued to increase at a decelerating rate during 2003-2008, while wheeze/asthma prevalence remained unchanged during the same 5-year period.