Long-term health effects of syphilis in cardiovascular diseases and neurological diseases: A systematic review and meta-analysis

Syphilis, caused by Treponema pallidum, remains a significant public health concern globally. While early treatment can prevent the acute effects, syphilis has been linked to long-term neurological and cardiovascular complications. However, the magnitude of this association remains unclear. This meta-analysis aims to evaluate the association between syphilis and the incidence of neurological and cardiovascular diseases, providing a comprehensive overview of the long-term health risks associated with syphilis infection. We systematically reviewed and synthesized data from 14 clinical trials published through 2024. A total of 792 syphilis patients and 563 controls were included in the analysis of neurological outcomes, and 21,139 syphilis patients and 22,640 controls were analyzed for cardiovascular outcomes. A fixed-effect model was used due to low heterogeneity, assessed by I2 statistics. The meta-analysis found a significant increase in the incidence of neurological diseases in syphilis patients, with a mean difference of 2.53 (95% confidence interval: 1.78-3.59, P < .00001). Similarly, syphilis was associated with a higher risk of cardiovascular diseases, showing a mean difference of 2.85 (95% confidence interval: 2.64-3.07, P < .00001). Both analyses showed low heterogeneity (I2 = 0.53, P = .05 for neurological and I2 = 0.94, P < .00001 for cardiovascular outcomes). Syphilis is significantly associated with both neurological and cardiovascular diseases, highlighting the importance of early detection and treatment to prevent these long-term complications.