(P371) Social determinants of health and sexually transmitted infection disparities in California, 2013 - 2021

Background:

Institutionalized racism contributes to community segregation and adverse social determinants of health (SDoH). These consequences manifest as unequal access to opportunities and contribute to disparities in disease burden between different populations. Understanding SDoH distribution can identify opportunities to intervene and mitigate the disproportionate and inequitable distribution of sexually transmitted infections (STIs). We aimed to describe the relationship between SDoH and California’s STI morbidity.

Methods:

The California Healthy Places Index (HPI) is a composite geospatial index that includes economic, education, social, and other neighborhood indicators that correlate with life expectancy. United States 2010 census tracts are scored using the HPI and aggregated into quartiles; residents of lower scoring HPI quartiles have fewer community opportunities to lead healthy lives. Using California surveillance data from 2013–2021, chlamydia, gonorrhea, early syphilis (primary, secondary, and early non-primary non-secondary), and syphilis of late/unknown duration incidence rates (IR) and rate ratios (RR) were calculated for each HPI quartile and by race/ethnicity.

Results:

IR were highest in the lowest scoring HPI quartile and lowest in the highest scoring HPI quartile for chlamydia (4,957.2 cases/100,000 persons vs. 2,176.9 cases/100,000 persons), gonorrhea (1,607.4 vs. 786.5), early syphilis (348.3 vs. 189.1), and syphilis of late/unknown duration (164.9 vs. 43.3). Residents in communities in the lowest scoring quartile had 1.8x the risk for early syphilis, 2.0x the risk for gonorrhea, 2.3x the risk for chlamydia, and 3.8x the risk for syphilis late/unknown duration, compared to residents in the highest scoring quartile. Among those residents in the lowest scoring quartile, Black/African American individuals had 5.8x the risk of having any bacterial STI compared to Asian and Native Hawaiian/Other Pacific Island individuals, who had the lowest IR (Figure 1).

Conclusion:

Residents of the lowest scoring HPI quartiles had the greatest STI burden in California. Among those in the lowest scoring quartile, there was a disproportionate burden of cases among Black or African American individuals. STI incidence is associated with SDoH and efforts to reduce disparities in sexual health should take broader social drivers of health into account.