Racial/ethnic differences in time from HIV diagnosis to AIDS diagnosis in San Diego County

Background: Disparities in race/ethnicity are of concern in HIV/AIDS prevention and treatment. Recently, there has been some evidence for differences in disease progression across races/ethnicities. To assess the extent of these differences in San Diego County, a comparison was made between races/ethnicities of the time from HIV diagnosis to AIDS diagnosis among reported AIDS cases. Methods: The proportion of cases by race/ethnicity progressing from HIV to AIDS diagnosis in less than a month (essentially simultaneous diagnoses), and less than a year, was determined from the HIV/AIDS Reporting System (HARS) registry for the County of San Diego. This registry includes all AIDS cases reported in County residents. These proportions are reported for 5-year time periods and compared for significant differences. Data are categorized as less than a month or less than a year because of the skewed distribution of times. Results: The proportion of simultaneous diagnoses in all cases was 30.3% in 2003-2007, with Hispanics (36.5%) significantly higher than whites (25.2%) or African Americans (26.8%). The proportion of all cases with less than a year between diagnoses was 52.3%; Hispanics (62.9%) again had a higher proportion than either whites (44.2%) or African Americans (45.7%). Additionally, Hispanics had greater and more consistent increases in proportion over time than other race/ethnicities. Conclusions: There are significant differences in proportion of cases progressing from HIV to AIDS diagnosis across races/ethnicities, particularly in Hispanics. The most likely cause of this phenomenon is testing later in the course of infection.