Emerging Regional and Racial Disparities in the Lifetime Risk of Human Immunodeficiency Virus Infection Among Men who Have Sex With Men: A Comparative Life Table Analysis in King County, WA and Mississippi.

BACKGROUND: Little is known about the lifetime risk of human immunodeficiency virus (HIV) diagnosis among US men who have sex with men (MSM), trends in risk and how risk varies between populations.

METHODS: We used census and HIV surveillance data to construct life tables to estimate the cumulative risk of HIV diagnosis among cohorts of MSM born 1940 to 1994 in King County, Washington (KC) and Mississippi (MS).

RESULTS: The cumulative risk of HIV diagnosis progressed in 3 phases. In phase 1, risk increased among MSM in successive cohorts born 1940 to 1964. Among men born 1955 to 1965 (the peak risk cohort), by age 55 years, 45% of white KC MSM, 65% of black KC MSM, 22% of white MS MSM, and 51% of black MS MSM had been diagnosed with HIV. In phase 2, men born 1965 to 1984, risk of diagnosis among KC MSM declined almost 60% relative to the peak risk cohort. A similar pattern of decline occurred in white MS MSM, with a somewhat smaller decline observed in black MS MSM. In phase 3, men born 1985 to 1994, the pattern of risk diverged. Among white KC MSM, black KC MSM, and white MS MSM, HIV risk increased slightly compared with men born 1975 to 1984, with 6%, 14%, and 2% diagnosed by age 27 years, respectively. Among black MS MSM born 1985 to 1994, HIV risk rose dramatically, with 35% HIV diagnosed by age 27 years.

CONCLUSIONS: The lifetime risk of HIV diagnosis has substantially declined among MSM in KC and among white MSM in MS, but is rising dramatically among black MSM in MS.