Community Practicum Project: Part 1-3

Correlates of Syphilis in Men Who Have Sex With Men in Norfolk, Virginia: A Cross-sectional Analysis.

Clay Porter, M.P.H.

Abstract:

Word Count: 247 (250 words allowed)

Syphilis is a sexually transmitted infection that, if left untreated, can cause serious health problems including neuralgic (brain and nerve) problems, eye problems, and even blindness¹. In addition, syphilis is linked to an increased risk of transmission of HIV. The United States is reporting the highest numbers of syphilis cases in over 20 years, according to Centers for Disease Control and Prevention (CDC).¹ In Virginia, there was a 40% increase in the number of reported syphilis cases between 2015-2016²; and early reporting³ indicates that rates are on the rise. Surveillance data from Virginia Department of Health (VDH) reveals that Eastern Virginia bears the greatest burden of disease, and Norfolk represents the highest number of cases in the region.³ In 2017, the number of reported syphilis cases in Norfolk, Virginia was 105, ranking it third among cities with the highest incidence of infection. African American men who have sex with men (MSM) are the population most at-risk of syphilis infection.^2-3 However, local data does not investigate the prevalence of syphilis among sexual minorities. Considering most cases of syphilis in the United States are among gay, bisexual and other MSM⁴, this study is the first to estimate the prevalence and correlates of risk linked to syphilis infection using population data. By examining why young African-American males are testing positive for the virus at higher rates than any other demographic, results from this study will be used to develop targeted program interventions that address syndemic health disparities in MSM communities. 

Introduction: Review of the Literature on Syphilis in MSM

Syphilis has made a dramatic resurgence in Hampton Roads over the past several years and African American MSM have been hit hardest by this emergent health problem. While MSM account for only 4% of the U.S. male population, they account for about two thirds of reported syphilis cases⁴. The current situation is stark, with reported syphilis rates among MSM having increased 64% from 2013⁵. Despite substantial advances in testing and treatment, the infection rate among MSM, and particularly young MSM, remains high, even as it has been dropping among other risk groups⁶. The spread of syphilis among African American MSM in Norfolk is syndemic. Numerous interrelated health problems have come together to interact with one another, creating a unique set of issues for identifying the underlying patterns of causation and consequences for public health in the region.

Throughout the literature, various correlates were determined to have an additive effect, each one intensifying the others. Depression, substance use, nonvolitional sex, and high risk sexual behavior in the context of poverty and cultural experiences such as stigma, shame, and self-denial, make African American MSM uniquely vulnerable to syphilis infection. Inequities in the public health care delivery system has left sexual minorities without the resources they need to overcome the challenges posed by this health crisis; and a lack of specific knowledge on the population in question has presented researchers with challenges in determining causality. Available data on sexual minority health is limited, making it difficult to estimate the prevalence of disease in the community. There is no approximation of the current number of MSM in Hampton Roads, or of their geographical distribution. Identifying individuals at-risk of syphilis infection that are both African American and MSM without local population data is a barrier to understanding this problem.    

The history of syphilis infection in MSM communities and the failure of various risk reduction strategies have informed this study by laying out what approaches to research and intervention have already been used to address the problem. Health activists have systematically resisted the application of the full range of public health strategies traditionally used to prevent the spread of such diseases; primarily because of the denominator problem in estimating prevalence, and their narrow interpretations of sexual minority health. Understanding the dynamics of syphilis transmission can provide insight into syphilis prevalence among African American MSM and inform prevention efforts to reduce the incidence of syphilis in this community.

Methods: Descriptive, Cross-sectional Survey 

Using cross-sectional methods, this study was designed to estimate MSM concentration factors and population sizes, and calculate MSM-specific local syphilis prevalence and yearly rates of diagnosed syphilis, as well as identify correlates of risk associated with increased incidence of infection in the region. A survey of sexual minorities was used to evaluate the current landscape of syphilis in Hampton Roads and establish a more thorough understanding of susceptibility and transmissibility in the specific context of exposure to syphilis infection.  Descriptive methods were embedded in the study design and used to guide the analysis and development of data collection instruments. The research process outlined in Figure 1 illustrates how measures of risk were identified and used to make causal inferences about disease exposure and risk. Data was collected via field surveys and data recorded in existing syphilis surveillance systems. Survey questions covered the domains being examined and were specifically designed to estimate disease prevalence in this community. Descriptive statistical analysis was employed in the study to calculate correlations between several different variables. Chi Square Test of Independence was used to determine any associations between nominal data collected in the survey, and McNemar’s test was used to test the significance of the difference between these correlated proportions.

The population in question was chosen because of the overwhelming burden of disease in the community. In Figure 2, the prevalence of syphilis is compared across the state, and illustrates how Norfolk is uniquely affected by this syphilis crisis. Participants were chosen based on their sexual experiences and medical history. Selection bias was controlled by increasing the sample size to include all individuals with correlates of risk for syphilis infection in the region that identified as male and reported ever having sex with a male.  Data from 569 participants in this 2019 cross-sectional examination reported high risk behaviors, such as sex without a condom or drug use. Multivariable logistic regression was used to examine factors related to risk of syphilis infection and establish associations between correlates and prevalence.  Sample weights were adjusted using STATA-15 programming.

A Scatterplot and Pearson’s R Test was also used to illustrate what the data looked like in a graph form, and the degree of linear correlations between the paired data. Correlates were positively associated with increased incidence of syphilis in the population. Some of these risk factors included sexual behaviors such as receptive or penetrative anal sex, sex with multiple partners, sex without a condom, sex under the influence of alcohol or illicit drugs, and nonvolitional sex.  There were also socioeconomic and behavioral correlates, such as MSM who reported an annual income less the $30,000/year, MSM who reported having sex with both women and men, and MSM who reported sexual debut before age 16.

All individuals involved in the cross-sectional study were asked questions related to their medical history, socioeconomic status, sexual experiences, and behavioral risk patterns. Categorical variables were measured and compared to one another using Bayesian modeling. This project is the first study to use population-based data to estimate the prevalence and correlates of risk for syphilis infection in Norfolk’s African American MSM communities. It serves as an example of how cross-sectional methods can be used to obtain a “snap-shot” of the community and describe the factors contributing to higher disease prevalence.

Results and Analysis: Interpreting Risk

Combining general population data, MSM online surveys and notification data allowed for the calculation of realistic estimates of local MSM populations and thus proportions of MSM with diagnosed syphilis or HIV co-infection. The results of this study have implications for prevention planning, commissioning of health services and counselling MSM on HIV/STI risk, as well as public policy agenda setting for special protections in sexual minority communities.

Over 18% of MSM in Norfolk reported sexual risk factors, such as sex without a condom, among which 78% were below 27-year-old at first experience. Over 31% of MSM ever had sex with a female, 45% used illicit drugs in past 12 months and 19% reported ever having STIs. Experiencing forced or nonvolitional sex was associated with incidence of syphilis infection and household income below $30,000 (OR:1.84; 95% CI:1.02-3.35), being ever-married (OR:2.10; 95% CI:1.23-3.57), using illicit drugs (OR:2.09; 95% CI:1.32-3.32) and ever having STIs (OR:1.90; 95% CI:1.13-3.21). Findings demonstrated socioeconomics, marital status, and illicit drug use were related to increased risk for syphilis in MSM in Norfolk. These results highlight the need for evidence-based multicomponent interventions to address syndemic health disparities in this population.

Syphilis rates in Norfolk depend on the community’s capacity to identify correlates of risk and develop strategies for dismantling them. Prevention tools, such as condoms, risk-reduction counselling and syphilis screening and treatment, can alter syphilis rates by modifying risk parameters; but without equitable treatment for African American MSM, the prevalence of syphilis will continue to burden this community. This project is evidence that sexual orientation is not a risk factor of its own kind; but rather, the subjective experience of being a sexual minority exposes individuals to syndemic health disparities that are the result of structural inequities in culture, health, and society. Only a culturally competent public health campaign designed to disentangle the correlates of risk will reduce the burden of disease in this city.

References:

1.       STD Data and Statistics. Centers for Disease Control and Prevention. https://www.cdc.gov/std/stats/. Published 2017. Accessed February 21, 2019.

2.       Virginia Department of Health. Go to Virginia Department of Health. http://www.vdh.virginia.gov/data/sexually-transmitted-infections/. Published 2017. Accessed February 19, 2019.

3.       Virginia Department of Health. Go to Virginia Department of Health. http://www.vdh.virginia.gov/surveillance-and-investigation/hai/ip/. Published 2017. Accessed February 19, 2019.

4.       What MSM Can Do About Syphilis | Syphilis | CDC. Centers for Disease Control and Prevention. https://www.cdc.gov/std/syphilis/CTAmsm.htm. Accessed April 24, 2019.

5.       Syphilis - 2017 Sexually Transmitted Diseases Surveillance. Centers for Disease Control and Prevention. https://www.cdc.gov/std/stats17/syphilis.htm. Accessed April 24, 2019.

6.       Oleary D. The Syndemic of AIDS and STDS among MSM. The Linacre Quarterly. 2014;81(1):12-37. doi:10.1179/2050854913y.0000000015.