IMPACT OF NEW ANTIRETROVIRAL COMBINATION THERAPIES IN HIV-INFECTED PATIENTS IN SWITZERLAND - PROSPECTIVE MULTICENTER STUDY

Objectives: To examine trends in disease progression and survival amon g patients enrolled in the Swiss HIV cohort study during 1988-96 and t o assess the influence of new antiretroviral combination therapies. De sign: Prospective multicentre study, with follow up visits planned at six monthly intervals. Setting Seven HIV units at university centres a nd cantonal hospitals in Switzerland. Patients: 3785 men (mean age 35. 0 years) and 1391 women (30.3 years) infected with HIV 2023 participan ts had a history of intravenous drug misuse; 1764 were men who had sex with men; 1261 were infected heterosexually; and 164 had other or unk nown modes of transmission. 601 participants had had an AIDS defining illness. Results: During more than 15 000 years of follow up, there we re 1456 first AIDS defining diagnoses and 1903 deaths. Compared with t hose enrolled during 1988-90, the risk of progression to a first AIDS diagnosis was reduced by 18% (relative risk 0.82 (95% confidence inter val 0.73 to 0.93)) among participants enrolled in 1991-2, by 23% (0.77 (0.65 to 0.91)) among those enrolled in 1993-4, and by 73% (0.27 (0.1 8 to 0.39)) among those enrolled in 1995-6. Mortality was reduced by 1 9% (0.81 (0.73 to 0.90)), 26% (0.74 (0.63 to 0.87)), and 62% (0.38 (0. 25 to 0.97)) respectively. Compared wth no antiretroviral treatment, t he risk of an initial AIDS diagnosis after CD4 lymphocyte counts fell to < 200 cells x 10(6)/l was reduced by 16% (0.84 (0.73 to 0.97)) with dual therapy, and 42% (0.58 (0.37 to 0.92)) with triple therapy. Mort ality was reduced by 23% (0.77 (0.68 to 0.88)), 31% (0.69 (0.60 to 0.8 0)), and 65% (0.35 (0.20 to 0.60)) respectively. Conclusions: The intr oduction of antiretroviral combination therapies outside the selected patient groups included in clinical trials has led to comparable reduc tions in disease progression and mortality.