Trends in bronchial hyperresponsiveness, respiratory symptoms and lung function among adults: West and East Germany

Previous studies have shown higher prevalences of bronchial hyperresponsive ness (BHR), respiratory symptoms and atopic sensitization among adults in W estern Germany than in Eastern Germany. One of the aims of the joint projec t INGA (INdoor Factors and Genetics in Asthma) is to assess incidence, prev alence and trends for asthma, BHR and atopic diseases over a time period of 11 years (1990-2001) in the former West (Hamburg) and East Germany (Erfurt ), with special reference to indoor exposure. INGA was designed as a case-control study following a cross-sectional study performed from 1990 to 1992 within the European Community Respiratory Heal th Survey (ECRHS). The database consisted of 1159 subjects in Hamburg and 7 31 subjects in Erfurt from the ECRHS (age 20-44). In 1995-1996, 107 cases ( diagnosed asthma, positive specific serum IgE, positive skin prick or PD(20 )FEV(1)less than or equal to 2.0 mg methacholine at ECRHS) and 106 controls (none of the previous findings) participated in Hamburg (115 cases and 109 controls in Erfurt). The methodology was identical to the ECRHS and dose-r esponse slopes (DRS) of the methacholine challenge were calculated as an in dex of responsiveness. In the control group, median values of DRS were 0.028% mg(-1) (1990-1992) a nd 0.044 (1995-1996) (P < 0.01) in Erfurt. Corresponding values for Hamburg were 0.028 and 0.022 (NS). Corresponding values within the case groups wer e 0.041 and 0.049 (NS) for Erfurt, and 0.069 and 0.052 (P < 0.05) for Hambu rg. Thus, 4 years after the first survey, we found an increased BHR in the Erfu rt control group while the bronchial responsiveness remained unchanged for the Hamburg group. These trends in BHR, which indicate the expected converg ing tendency between East and West Germany, have to be confirmed within the next INGA-survey in 2000-2001.