Dramatic Declines in Lifetime HIV Risk and Persistence of Racial Disparities among
Men Who Have Sex with Men in King County, Washington, USA
IAS 2015VANCOUVER, CANADA
JULY 21, 2015
GALANT AU CHANAMY BENNETT
SUSAN BUSKINDAVID KATZ
MATTHEW GOLDEN
BackgroundIn the US, HIV disproportionately affects
MSM. The proportion of cases occurring in black
MSM is increasing. Life tables can be used to estimate the
lifetime risk of HIV diagnosis within age cohorts.
MethodsWe constructed life tables for 1982-2012 to
estimate the cumulative risk of HIV diagnosis among MSM born in 1940-1994.U.S. Census data to define size of male
populations in King County, Washington6% of male population in King County
estimated to be MSM, reflecting net in-migration during ages 18-29
Local surveillance data to define # of HIV diagnoses in MSM each year, by age and race
Cumulative Risk of HIV Diagnosis Among MSM : A Comparison between Racial Categories
Birth cohortAbsolute
DifferenceRelative
Difference
1960-1964 18.14% 43.20%
1975-1979 7.95% 83.70%
SummaryCumulative risk of HIV diagnosis progressed in 3 phases:
Increased in MSM born 1940s – 1960s Highest risk in MSM born 1960-1964
Declined approximately 65% in those born after the mid-1960s
Risk plateaued in later birth cohorts, born after mid-1970sThis trend occurred in both black and white MSMSignificant racial disparities persist.
The largest absolute decrease in risk occurred in black MSMRelative disparities have increased in later birth cohorts
LimitationsUndiagnosed HIV infection not includedGeneralizability to other localitiesEstimation of MSM population imprecise,
although imprecision would not affect trend estimates
Changes in ascertainment of race in the US census
ConclusionsOur findings suggest that King County may
be aging out of the HIV epidemic.High rates of infection in young MSM in
some areas of the US suggest that such a trend is not ongoing nationally.
The absence of progress in young MSM presents a long-term problem, as high rates of infection early in the life course lead to high cumulative risk of HIV within a birth cohort.
AcknowledgmentsMatthew GoldenDavid KatzSusan BuskinAmy Bennett Julia DombrowskiChristine Khosropour
Funding: T32 Training grant AI007140-38