This was the conclusion of Ana María Irujo Andueza in her PhD thesis defended recently at the Public University of Navarra.

8,607 children in 66 centres.

The most common atopical illnesses in infancy are, besides asthma, atopical dermatitis and allergic rhinitis. Studies of a multicentre nature have shown a significant rise in these ailments throughout the world and the causes of the increase are, as yet, not sufficiently clear.

Within this context, the aim of the PhD thesis was to evaluate the prevalence of allergic rhinitis and atopical dermatitis amongst the school population in the area around Pamplona, the capital of Navarre, using parameters as sex, language, date of birth and school. The data obtained was compared with a previous study undertaken in 1994 in the same geographical zone, and against those carried out at other centres at a national and international level as part of the third phase of the International Study of Asthma and Allergies in Childhood (ISAAC).

In 2001 Ana María Irujo carried out a transversal epidemiological study - using questions from the ISAAC - on two populations of children, a group between 6- and 7- year-olds and another between 12 and 14, both groups being drawn from 66 schools and colleges, mostly in the Pamplona-Irunea city area but also from centres in Barañain, Zizur Mayor, Zizur Menor, Atarrabia, Huarte, Burlada and Mutilva Baja.

The first signs of asthma

Rhinitis and atopical dermatitis are considered to be "the first signs of asthma". The expression "allergic triad" is used to refer to dermatitis followed by rhinitis and ending up with asthma. The rhinitis is characterised by an increase in nasal secretion, also normally associated with conjunctival factors of the eyes that significantly affect the quality of life, given that exercise and physical activity in general are affected.

According to the study, for the group of 6- and 7-year olds, the current frequency of rhinitis is 14%, i.e. 1.33 times higher than in 1994, with a higher incidence amongst boys than girls. Moreover, the proportion (8.1%) of children between 6 and 7 with prior diagnosis for allergic rhinitis or hay fever doubled compared to the data for 1994.

However, amongst the group of children between 12 and 14, there is a greater incidence of rhinitis amongst girls (31.6% compared to 27.6% amongst boys). Moreover, amongst this age group, 37.9% had had rhinitis at some time; 29.5% currently suffer from the ailment and 15% have rhinoconjunctivitis. Thus, there is reason to believe that the problem is under-diagnosed.

Compared to the 1994 data, the study concluded that, amongst the group of adolescents, the incidence of rhinitis over the last year has dropped 1.37 times and that of accumulated rhinitis by 1.67 times.

Another factor thrown up by the study was the significant differences between Spanish-speakers and Basque-speakers. In both age groups a greater incidence of rhinitis was registered by those responding in Basque.

Stabilisation of dermatitis

As regards dermatitis, this is a pathology which is on the increase and which starts in early infancy. Most cases start before the age of two and are characterised by red marks that itch a lot, and that come and go.

The study undertaken showed that, amongst the population of 6- and 7-year-olds, the incidence of atopical dermatitis is currently greater amongst boys (10.1%) than amongst girls (7.5%). In the 12-14 group, on the other hand, girls predominate with dermatitis.

As regards gender, both in the 6 to 7 group and in the 12 to 14 one, girls are more prone to getting this illness. Also, the Basque-speaking school population shows a greater percentage of diagnosis for atopical dermatitis than the Spanish-speaking one (42.6% against 31.2%).

It should be pointed out that, in the older group, the symptoms of dermatitis, as with rhinitis, descended or stabilised over the seven years separating the two studies.