Clinical epidemiology and research on HIV infection in Switzerland: the Swiss HIV Cohort Study 1988-2000

Background and objectives: The Swiss HIV Cohort Study (SHCS) was initiated in 1988 and represented the main scientific component of the comprehensive response to the AIDS epidemic in Switzerland. It brought together physician s and scientists from five university hospitals (Basel, Berne, Geneva, Laus anne and Zurich) and two Cantonal hospitals (Lugano and St. Gallen). The ob jective of SHCS was, and still is, to produce rapid, high quality patient-o riented medical research in the field of HIV infection. Methods: SHCS is a prospective population-based cohort study. Any HIV-infec ted person aged greater than or equal to 16 years is eligible to participat e. Data collection and study procedures are standardised. Data quality and protocol monitoring are conducted at the coordination and data centre in La usanne. Detailed information on demographics, income, mode of HIV acquisiti on, risk behaviours, clinical events, laboratory results, treatment and tre atment tolerance is collected at registration and at 6-monthly intervals. Results: Since 1996, 10 600 persons have been enrolled and the SHCS study p opulation is considered fairly representative of the HIV-infected populatio n in Switzerland, at least in terms of gender and mode of HIV acquisition. In 1999, 4600 patients were actively followed up and more than 70% of patie nts were receiving highly active antiretroviral therapy (HAART). As a conse quence, mortality and the incidence of HIV-related opportunistic infections have decreased significantly in the recent past. Between 1996 and 2000, 91 original manuscripts have been published by SHCS scientists and physicians , almost exclusively in peer-reviewed journals. A wide range of scientific questions have been addressed, including HIV primary infection, the natural history of HIV infection, the clinical and biological impact of HAART, dru g resistance, risk factors for disease evolution including the timing of tr eatment initiation, the role of CD4 receptors, the validity of HIV surveill ance reports, determinants of treatment access and tolerance, clinical tria ls of new drug combinations, the interruption of prophylaxis following a fa vourable response to HAART and issues relating to quality of life and inter action between income, social level and disease evolution. Conclusion: The SHCS has had, and continues to have, a significant impact o n medical practice, public health and research in Switzerland and beyond. I t represents a network of excellence which has brought together and fostere d intensive collaboration between physicians and institutions throughout th is country and beyond. This was possible thanks to the support of the Feder al Office of Public Health and the commitment of primary care physicians, r esearchers and patients. This project may be a model for focused and priori tised multicentre and transdisciplinary research programmes.