[1] Karolinska Hosp & Inst, Div Resp Med, Dept Med, Stockholm, Sweden
[2] Karolinska Hosp & Inst, Div Clin Immunol & Allergy, Dept Med, Stockholm, Sweden
[3] Karolinska Inst, Dept Med, S-10401 Stockholm, Sweden
[4] Stockholm Cty Council, Stockholm, Sweden
[5] Univ Stockholm, Natl Inst Working Life, S-10691 Stockholm, Sweden
[6] Univ Stockholm, ITM, S-10691 Stockholm, Sweden
[7] Astra Zeneca, Clin Sci, Lund, Sweden