The role of social class in allergic diseases has changed over 30 years

The rising prevalence of hay fever in Western Europe during the 19th century was linked to industrialisation, and started in the affluent classes.

The role of social class in allergic diseases has changed during the second part of the 20th century, according to a new study undertaken by Finn Rasmussen (Child and Adolescent Public Health Epidemiology Group, Karolinska Institutet, Stockholm, Sweden) and colleagues.

The two most important strengths of this study are the exceptionally large study population and the consistency of the data collection.

It is based on the annual military service examinations and covers 1,247,038 male conscripts, in all 90% of all men born in Sweden between 1952 and 1977.

The study shows a four-fold increase in allergic asthma over a period of less than three decades and illustrates the epidemic of asthma and hay fever in Sweden after the 1950s.

The rise of asthma and hay fever has affected all social classes, but the steepest increase occurred in conscripts from less advantaged social classes. A low socioeconomic status implied a reduced risk of allergic asthma in conscripts born in the 1950s but an increased risk in conscripts born in the 1970s.

The authors speculate that tobacco smoking contributes to the increased risk of asthma in low social classes, but differences in housing conditions and food habits could also be important.

Title of the original article:
Social class in asthma and allergic rhinitis: a national cohort study over three decades

The European Respiratory Journal is the peer-reviewed scientific publication of the European Respiratory Society (more than 7,500 specialists in lung diseases and respiratory medicine in Europe, the United States and Australia).

EUROPEAN RESPIRATORY JOURNAL (ERJ), Vol. 26, No 6
http://erj.ersjournals.com