Characterizing Sociodemographic, Behavioral Correlates, and Trends of Non-binary/genderqueer Patients at Public Health Seattle and King County Sexual Health Clinic

Non-binary/genderqueer (NB/GQ) individuals are a distinct but understudied population within the LGBTQ+ community. We sought to characterize sociodemographic behaviors and STI outcomes for NB/GQ patients attending the Sexual Health Clinic (SHC) and examine how gender identity among SHC patients has evolved over time. Methods: We used Public Health Seattle-King County (PHSKC) SHC data from 2016-2023 to examine temporal changes in gender identity. We compared sociodemographic characteristics among cisgender (men and women), transgender, and NB/GQ patients using chi-squared tests to determine statistical significance. We used generalized estimating equations to compare the prevalence of syphilis, urogenital gonorrhea, rectal chlamydia, methamphetamine use, and non-prescribed injection drug use in NB/GQ patients to that in both cisgender men who have sex with men (MSM) and transgender patients. Results: Of 82,384 visits between 2016-2023, 1672 (2.0%), 867 (1.1%), and 79,845 (96.9%) were among NB/GQ, transgender, and cisgender patients, respectively. The proportion of visits among NB/GQ and transgender patients increased over time, from 0.7% to 3.5% and 0.7% to 1.7%, respectively (p-trend<0.001). NB/GQ identity was more frequent among patients assigned female vs. male sex at birth (3.2% vs 1.8%, P<0.001), younger vs older patients (14-25 years: 3.1% vs 46+: 0.2%, p<0.001), and patients reporting White (2.3%) vs Black (1.0%) race (p<0.001). We found no significant differences in injectable drug and methamphetamine use across NB/GQ, cisgender MSM, and transgender patients. In models adjusted for age, sex assigned at birth, race, ethnicity, insurance, and housing status, we observed a marginally lower prevalence of syphilis among NB/GQ patients compared to cisgender MSM, with an adjusted prevalence ratio (aPR) of 0.98 (95% CI: 0.97-0.99). Additionally, we observed a lower prevalence of rectal chlamydia infection and urogenital gonorrhea infection among NG/GQ patients compared to cisgender MSM. For rectal chlamydia, the aPR was 0.40 (95% CI: 0.19, 0.82), and for urogenital gonorrhea, the aPR was 0.35 (95% CI: 0.16, 0.77). STI outcomes did not differ between NB/GQ and transgender patients. Conclusion: Given the rapidly increasing gender diversity among clinic attendees, our findings indicate that NB/GQ patients exhibited a lower prevalence of bacterial STIs, such as syphilis, rectal chlamydia, and urogenital gonorrhea, compared to cisgender MSM. This underscores the need for continued monitoring of behaviors and STI outcomes in distinct gender-diverse groups. Such data is imperative to tailor STI and HIV prevention strategies appropriately.