The prognostic value of the World Health Organisation staging system for HIV infection and disease in rural Uganda

Objective: To assess whether the WHO staging classification for HIV provide s prognostically Valuable and applicable information in rural Uganda. Patients and study design: Data were obtained from a population-based cohor t of 232 HIV-infected individuals. Methods: Clinical information was obtained using a detailed questionnaire a nd ascertained by physical examination. Participants were seen routinely ev ery 3 months and when they were sick. A computer algorithm based on clinica l history, examination and laboratory findings was used to stage HIV-positi ve participants at each routine visit. Kaplan-Meier survival estimates and the Cox proportional hazard model were used to assess the prognostic streng th of the clinical and laboratory categories of the system. Results: An attendance rate of 81% and 799 person-years of follow-up were a chieved. Survival probability estimates at 6 years from being seen in clini cal stages 1, 2, 3 and 4 were 63, 46, 24 and 6% respectively. When staging was revised to incorporate lymphocyte categories, the survival probabilitie s were 73, 62, 39 and 6% respectively. Unexplained prolonged fever and seve re bacterial infection had survival probabilities closer to stage 2 conditi ons, mucocutaneous herpes simplex virus infection for more than 1 month and crytosporidiosis with diarrhoea for more than 1 month closer to stage 3 an d oral candidiasis closer to stage 4 conditions. Conclusions: Even without the laboratory markers, the clinical category of the WHO staging system is useful for predicting survival in individuals wit h HIV disease. This is important for areas with limited access to laborator y markers. A simple rearrangement of a few clinical conditions could improv e the prognostic significance of the WHO system. (C) 1999 Lippincott Willia ms & Wilkins.