Global, regional, and national burden and trends of syphilis among women of childbearing age from 1990 to 2021

Abstract

Background: Syphilis represents a significant sexual health concern for women of childbearing age (WCBA) worldwide. However, information regarded the burden and trends associated with this disease is limited. This study aimed to evaluate the changes in syphilis burden among WCBA aged 15-49 years from 1990 to 2021 at global, regional, and national levels.

Methods: The extensive information was gathered from the Global Burden of Disease (GBD) 2021 database concerning the incidence, prevalence, and disability-adjusted life years (DALYs) related to syphilis in WCBA aged 15-49 across 204 countries and territories from 1990 to 2021. To quantify temporal trends, the estimated annual percentage change (EAPC) was calculated in age-standardized rate (ASR) for incidence, prevalence, and DALYs based on age group, region, and sociodemographic index (SDI). The relationship between ASR and SDI was examined using spearman correlation analysis.

Results: In 2021, there were 20.48 million prevalent cases, 5.36 million new syphilis cases, and 39.59 thousand DALYs among WCBA, reflecting increases of 45.85, 46.96, and 16.08%, respectively, since 1990. Over 32 years, global rates of prevalence, incidence, and DALYs declined, with EAPCs of -0.50, -0.35, and -1.30. However, high-middle SDI regions experienced rising trends in incidence (EAPC: 0.28) and prevalence (EAPC: 0.22). The Low-middle SDI region had the highest syphilis cases among WCBA, accounting for about one-third of the global total. Notably, the 20-24 age group had the highest incidence rate at 467.35 per 100,000.

Conclusion: Our findings highlight a decline in the global prevalence of syphilis from 1990 to 2021, the burden of this disease remains significant in low-and middle-income countries and regions. The development of more effective strategies to prevent and reduce the burden of syphilis is a pressing need.

Keywords: age-standardized rate; burden of disease; estimated annual percentage change; syphilis; women of childbearing age.

Figure 1

Temporal trend of syphilis burden in WCBA across 5 SDI regions: (a) Percentage change in cases of prevalent, incident, and DALYs in 1990 and 2021; (b) The EAPC of prevalence, incidence, and DALYs rates from 1990 to 2021; (c) The rates of incidence from 1990 to 2021. WCBA, women of childbearing age; EAPC, estimated annual percentage change; DALYs, disability-adjusted life years; SDI, sociodemographic index.

Figure 2

Temporal trend of syphilis burden in WCBA across 21 GBD regions: (a) Incidence rate per 100,000 population in 1990 and 2021; (b) Percentage change in cases of prevalent, incident, and DALYs in 1990 and 2021; (c) EAPC of rates of prevalent, incident, and DALYs from 1990 to 2021. WCBA, women of childbearing age; EAPC, estimated annual percentage change; DALYs, disability-adjusted life years; GBD, Global Burden of Disease.

Figure 3

Temporal trend of syphilis incidence in WCBA across 204 countries: (a) Age-standardized incidence rate (ASIR) in 2021; (b) Percentage change in incident cases in 1990 and 2021; (c) EAPC in incident rates from 1990 to 2021. WCBA, women of childbearing age; EAPC, estimated annual percentage change.

Figure 4

Temporal trend of syphilis burden in WCBA by age pattern across SDI and GBD regions: (a) The distribution of incident cases across 7 age groups as percentages in 1990 and 2021; (b) Percentage change in incident cases of 7 age groups in 1990 and 2021 across SDI regions; (c) EAPC of incident rates of 7 age groups from 1990 to 2021 across SDI regions. WCBA, women of childbearing age; EAPC, estimated annual percentage change; SDI, sociodemographic index; GBD, Global Burden of Disease.

Figure 5

The associations between the SDI and ASIR per 100,000 population of syphilis in WCBA across 21 GBD regions. WCBA, women of childbearing age; SDI, sociodemographic index; GBD, Global Burden of Disease; ASIR, age-standardized incidence rate.

Figure 6

The associations between the SDI and ASIR per 100,000 population of syphilis in WCBA across 204 countries. WCBA, women of childbearing age; SDI, sociodemographic index; ASIR, age-standardized incidence rate.

Figure 7

The associations between EAPC and ASR in 1990, and SDI in 2021: (a) The correlation between EAPC and ASIR, ASPR, ASDR in 1990 across 204 countries; (b) The correlation between EAPC and SDI in 2021 across 204 countries. WCBA, women of childbearing age; EAPC, estimated annual percentage change; SDI, sociodemographic index; ASR, age-standardized rate; ASIR, age-standardized incidence rate; ASPR, age-standardized prevalence rate; ASDR, age-standardized DALYs rate.