Background: In many states, public formularies provide access to antiretroviral medications for patients regardless of ability to pay or social circumstances. Analyzing geographic and demographic variation in HAART use is therefore vitally important in monitoring access and assuring equitable usage. Data are presented on patterns of HAART use for New York City (NYC) and the surrounding suburban Tri-County region of Westchester, Rockland, and Putnam counties.

Methods:  Data were obtained from interviews conducted with HIV-positive adults in NYC and the Tri-County region. The NYC cohort was recruited in 1994-1995 and refreshed in 1998 from a  randomly stratified sample of 43 medical and social service agencies. The cohort includes 968 individuals who have been interviewed as many as 8 times through 2002. A similar sampling strategy was employed to assemble a cohort of 398 HIV positive individuals in the Tri-County region in 2001-2002, recruited  from 28 medical and social service agencies. Analysis was restricted to 529 respondents diagnosed with HIV prior to 1998 who had an AIDS diagnosis.  Among these 529 respondents, 320 were from NYC  and 209 from Tri-County. Logistic regression analyses tested for geographic and demographic differences.

Results: Of the NYC cohort, 50% were using HAART, and of the Tri-County cohort, 43% were. Within  Tri-County, 65% of Rockland County residents were on HAART, compared with 38% of those living in the more urbanized southern section of Westchester and 41% of those living in the more suburban areas of northern Westchester and Putnam County. In both cohorts, 60% of non-Hispanic white participants reported current use of HAART. Non-Hispanic black and Hispanic respondents were less likely to use HAART, but the racial ethnic differences were statistically significant only for Tri-County (p <0.05), not for NYC. Controlling for sociodemographic differences, participants in southern Westchester were half as likely as NYC participants to be on HAART.

Conclusions: Although widespread, HAART is far from universal. More than half the combined New York City and Tri-County cohorts with an AIDS diagnosis are not currently on HAART.  Racial disparities are present, as are geographic differences. Although such findings suggest practice pattern variations, they do not precisely locate the causes of regional and ethnic disparities; they do focus attention on markers of unequal access that need to be addressed.

Keywords: HAART; small-area variation; disparities