Estimates of lifetime risk can be used to compare the burden of disease across populations. This method is frequently used to describe cancer risk, but has infrequently been used for HIV infection. We estimated the lifetime risk of an HIV diagnosis for sex, age, and racial/ethnic subgroups as well as by state.
HIV diagnosis, mortality, and census population data were used to derive lifetime and age-conditional risk estimates of being diagnosed with HIV. Data on HIV diagnoses (adjusted for reporting delays) were obtained from the National HIV Surveillance System (NHSS). The numbers of HIV diagnoses (NHSS) and non-HIV deaths (mortality data) between 2009 and 2013 were used to calculate probabilities of a diagnosis of HIV at a given age, conditional on never having developed HIV prior to that age using a competing risks method. The lifetime risk estimate is the cumulative probability of being diagnosed with HIV from birth. Age-conditional risk measures were the probabilities of an individual of a specified age being diagnosed with HIV within ten years. The lifetime and age-conditional risk estimates were calculated for the entire population and each combination of gender and race/ethnicity. Lifetime risk estimates were also calculated by state. All calculations were conducted in DevCan 6.7.3. Comparisons were made to findings from a 2004-2005 analysis.
Overall, the estimated lifetime risk of being diagnosed with HIV was 1.05%, meaning that approximately 3 million Americans (or 1 in 96 people) will be diagnosed with HIV in their lifetime. This was a decrease from a 2004-2005 estimate (1.29%). Among males the estimated risk was 1 in 62, and among females it was 1 in 221. At every age, males had a higher estimated lifetime risk than females (Figure 1). For males and females, the highest lifetime risk was among blacks (male: 1 in 19; female: 1 in 46). The estimated lifetime risk among Hispanics/Latinos was 1 in 47 among males and 1 in 214 among females. Among white males the lifetime risk was 1 in 127 and among white females it was 1 in 851. The lifetime risk estimates varied by state from 1 in 43 in Georgia to 1 in 662 in North Dakota. The highest lifetime risk was in Washington D.C. (1 in 13), an urban district.
The overall lifetime risk has decreased. However, without improvements in prevention, millions of Americans are expected to acquire HIV infection during their lifetime, and large disparities persist by sex and race/ethnicity.