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 White MSM

Cumulative Risk of HIV Diagnosis Among White MSM

Cumulative Risk of HIV Diagnosis Among White MSM

Cumulative Risk of HIV Diagnosis Among White MSM

Cumulative Risk of HIV Diagnosis Among White MSM

Cumulative Risk of HIV Diagnosis Among White MSM

Cumulative Risk of HIV Diagnosis Among White MSM

Cumulative Risk of HIV Diagnosis Among White MSM

Cumulative Risk of HIV Diagnosis Among Black MSM

Cumulative Risk of HIV Diagnosis Among Black MSM

Cumulative Risk of HIV Diagnosis Among Black MSM

Cumulative Risk of HIV Diagnosis Among Black MSM

Cumulative Risk of HIV Diagnosis Among Black MSM

Cumulative Risk of HIV Diagnosis Among Black MSM

Cumulative Risk of HIV Diagnosis Among Black MSM

Cumulative Risk of HIV Diagnosis Among Black MSM

Cumulative Risk of HIV Diagnosis Among MSM : A Comparison between Racial Categories

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

Questions?