[1] Hosp Lugano, Lugano, Switzerland
[2] Univ Lausanne Hosp, Lausanne, Switzerland
[3] Swiss HIV Cohort Study Data Ctr, Lausanne, Switzerland
[4] Univ Zurich Hosp, CH-8091 Zurich, Switzerland
[5] Univ Hosp Bern, CH-3010 Bern, Switzerland
[6] Univ Basel Hosp, CH-4031 Basel, Switzerland
[7] Univ Hosp Geneva, Geneva, Switzerland
[8] Univ Bristol, MRC, Hlth Serv Res Collaborat, Dept Social Med, Bristol BS8 1TH, Avon, England