Trends, patterns, and factors associated with HIV infection among males diagnosed with syphilis, 2014-2019, Hawaii

Objective: This study describes HIV infection and associated risk factors among males diagnosed with syphilis in Hawaii.

Methods: Hawaii sexually transmitted infection (STI) registry records of males diagnosed with syphilis, 2014-2019, were crossmatched with Hawaii HIV surveillance registry records through 2020 using CDC's Registry Plus Link Plus software. HIV status from the STI registry was validated by matching results. Logistic regression was used to examine demographic and behavioral factors associated with HIV infection.

Results: Among the 947 male syphilis cases, 257 (27.1%) had both syphilis and HIV infections. Dual infection rates were higher in earlier years (39.5% in 2015), among older patients (41.6% among persons ≥45 years old), males who have sex with males (MSM, 36.6%), and cases with repeated syphilis events (59.5%). The overall agreement on HIV status between the STI registry and matching results was 95.7%.

Conclusions: Over a quarter (27.1%) of male syphilis cases were living with HIV. HIV infection rates were higher among older patients, MSM, and males with repeated syphilis events. Periodic matching between STI and HIV registries provides opportunities for quality control to both registries and opportunities to identify patients not linked to HIV care or who have fallen out of HIV care.