Rural-urban differences in HIV viral loads and progression to AIDS among new HIV cases

The human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) epidemic in the United States has shifted to the South, where an increasing proportion is occurring in rural areas. We sought to gain a better understanding of the affected rural population in this region.

The statewide HIV/AIDS Electronic Reporting System database was used to examine the epidemiological characteristics of newly diagnosed HIV cases in South Carolina from 2005 to 2011. Rural-urban differences were examined in sociodemographic and clinical characteristics, including progression to AIDS and a decline in HIV viral load (VL) to undetectable levels within 1 year of diagnosis.

Of the 5336 individuals newly diagnosed as having HIV, 1433 (26.9%) were from rural areas. Compared with urban residents, a higher proportion of rural residents were black, non-Hispanic (80.1% vs 68.5%; P ≤ 0.0001) and reported heterosexual risk (28.8% vs 22.9%; P = 0.0007). The proportion of female patients was higher in rural areas (29.7% vs 26.4%; P = 0.016). No significant rural-urban differences were found in initial CD4(+) T-cell and VL counts or proportion obtaining an undetectable VL at 1 year. Rural residents were significantly more likely than urban residents to have AIDS at diagnosis or within 1 year of the HIV diagnosis (adjusted odds ratio 1.15; 95% confidence interval 1.007-1.326).

The reasons behind differences in proportions of rural and urban residents who were diagnosed as having AIDS or progressed to AIDS despite similar initial CD4(+) T-cell counts and VL suppression at 1 year are unclear and should be explored in future studies. Future prevention and treatment efforts may need to consider the unique characteristics of rural populations in the South.