Progression to AIDS or death following diagnosis with a class IV non-AIDS disease: utilization of a surveillance database.

Time to progression to an AIDS-defining disease or death was analyzed for residents of King County, Washington State, with selected class IV non-AIDS diagnoses. Relative to people with constitutional symptoms, the risk of progression to an AIDS-defining diagnosis was 1.4 [95% confidence interval (CI), 0.8-2.2), 1.6 (95% CI, 1.0-2.5), and 2.1 (95% CI, 1.3-3.5) times greater for people with a diagnosis of oral hairy leukoplakia, oral candidiasis, and multiple diseases, respectively. Relative to subjects with CD4 counts of > or = 200, the risk of progression to AIDS was greater for subjects with CD4 counts < 200; relative risks ranged from 2.3 (95% CI, 0.8-6.6) for subjects with constitutional symptoms and CD4 counts < 200 to 6.7 (95% CI, 3.3-13.6) for subjects diagnosed with oral hairy leukoplakia and CD4 counts > 200. However, the statistical test for interaction between CD4 count and diagnostic group was not significant (p = 0.62). Our findings are in general agreement with results from previous cohort studies and suggest the utility of surveillance databases for natural history studies of the course of HIV illness.