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Analyzing the Prevalence and Associated Demographics of Syphilitic Retinitis and Syphilis in a Large U.S. Cohort
Caroline K Redick1,2,3, Sonia B Kim1,2, Alison Zhao1,2,3
1Department of Medical Education, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA.
Purpose:
To determine the prevalence of syphilis and syphilitic retinitis (SR) from 2017-2024.
Methods:
Data were analyzed using a large U.S. electronic health platform. Patients were identified by ICD-10 encounter diagnosis codes and further stratified by age, race/ethnicity (White, Black, Hispanic, or Latino), and sex. Prevalence of SR and syphilis was calculated from 2017 to 2024. Prevalence odds ratios (OR) were used to approximate the risk of SR and syphilis among sub-groups, with significance defined as OR < 0.9 or >1.1.
Results:
Among patients with ICD encounter diagnostic codes of syphilis, 3,016 per 100,000 had SR, equating to a 1.48-fold increase from 2017 to 2024. Adults aged 41-60 years had the highest prevalence of SR among age groups (4.18 per 100,000, 2024). Males exhibited higher OR of SR than females across all age groups, except the 41-60-year group (OR: 1.12, 95% CI: 1.01, 1.24). Whites had greater odds of SR than Blacks among all age groups. White males exhibited the largest increase in overall prevalence of SR, from 1.58 to 2.84 per 100,000 (2017-2024). The rise in SR was significantly greater than the rise in syphilis cases from 2017 to 2024 (ratio of change: 1.48, 95% CI: 1.29, 1.70).
Conclusion:
The prevalence of SR is not only rising alongside syphilis but is exceeding the rise in syphilis cases from 2017 to 2024, especially in White males and middle-aged adults (41-60 years). These findings underscore the need for increased awareness among providers and targeted screening to prevent vision-threatening complications of SR.
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