HEPATITIS B VIRUS (HBV) INFECTION continues to be one of the most frequently reported preventable diseases in the United States, despite the licensure of a vaccine in 1982. 1 In the United States, an estimated 240,000 new infections occur annually, 1 and currently an estimated 1.25 million individuals in this country are chronically infected with HBV. 2–5 Sequelae resulting from chronic HBV infection include cirrhosis of the liver and hepatocellular carcinoma, and an estimated 6,000 deaths occur annually from these complications. 6–9
Because HBV can be transmitted through sexual activity, 10 the U.S. Centers for Disease Control and Prevention (CDC) and the U.S. Gay and Lesbian Medical Association recommend vaccination against HBV for all men who have sex with men (MSM), 1,11 a group for whom HBV has been identified as one of the most important sexually transmitted diseases (STDs). 1,12–15 However, available national epidemiologic data and results of community-based HBV vaccination programs indicate that the majority of MSM are not vaccinated. 13,15,16
Estimates of the prevalence of previous HBV infection in this population range from 5% to 81%; prevalence of hepatitis B surface antigen (HBsAg) varies from 1% to 11%. 17,18 Self-reported vaccination rates among sexually active MSM are low, ranging from 11% to 48%. 12,15,18–23
Recent studies examining HBV infection by race indicate a substantially higher incidence of new HBV infections as well as a higher level of HBV prevalence among blacks. 2,5,24 Despite the low rates of vaccination among MSM and the increased incidence and prevalence among blacks, little is known about HBV vaccination acceptance that could help guide tailored intervention efforts 12,16,18,21–23,25,26. Although the association of race with disease most likely is a proxy for some other characteristic, 27,28 understanding vaccination behavior among subgroups is essential to ensure that appropriately tailored, effective intervention strategies are designed and implemented.
In this study, we sought to explore the psychosocial variables that may affect HBV vaccination acceptance among a conventional outreach sample of black MSM. Findings from this study may inform intervention efforts to increase vaccination rates among black MSM, a subsample of MSM that is particularly neglected in the HBV vaccination behavioral literature. 29 Findings from this study also may inform future interventions designed to enhance vaccination within this population as vaccines against HIV and hepatitis C become available.
Constructs from two of the most widely used behavior change theories 30 were integrated to identify theory-based correlates of HBV vaccination among a convenience sample of MSM. The theories used in this study of HBV vaccination included the health belief model (HBM) 30–34 and the social cognitive theory. 35–37 These theories have been used successfully to explain factors that contribute to health behavior and the mechanisms by which these factors operate. 30
Among adult and adolescent MSM, the HBM has been used to understand sexual risk behavior, 38–41 HIV testing, 42,43 HIV treatment initiation, 44 and risk-reduction intervention participation and completion. 45 When applied to HBV vaccination, the HBM postulates that in order for individuals to participate in a health behavior, they must believe that (1) they are personally susceptible to HBV infection (perceived susceptibility); (2) contracting HBV would have a negative impact on their lives (perceived severity); (3) getting vaccinated against HBV would be beneficial (perceived benefits); and (4) getting vaccinated is not discouraged by insurmountable barriers (perceived barriers).
Perceived self-efficacy is a central concept within the social cognitive theory and is considered to be its most important construct. 35,37 Perceived self-efficacy is defined as the conviction that one can successfully execute the behavior required to produce the desired outcome in various situations. 35–37 Among MSM, perceived self-efficacy has been used to understand HIV sexual risk reduction behavior. 38,41,46–48 When applied to HBV vaccination, self-efficacy is the confidence that an individual perceives himself or herself to have to complete the three-dose vaccination series despite various perceived barriers and limitations.
To the best of our knowledge, this is the first published study to investigate theory-based attitudes and beliefs about HBV vaccination among black MSM, a group at increased risk of exposure to HBV.
Data Collection Procedures
During November 2001, data were collected anonymously in a predominantly black, “gay” male bar in Birmingham, Alabama, USA. All bar patrons were asked to participate regardless of perceived gender or race by a trained recruiter, who explained the study and assessed sobriety of potential participants on the basis of established criteria 49 to ensure informed consent. Questionnaires were self-administered and completed in secluded areas of the bars to enhance participants’ valid reporting of sensitive behaviors. Participants were compensated $10.00 for completing the survey. The data were entered into an electronic database with use of double-entry procedures to assess and validate accuracy.
The Birmingham Vaccine Acceptance Questionnaire included 69 items. Items measured participants’ sociodemographic characteristics, including age, race/ethnicity (American Indian or Alaska Native; Asian; black; Hispanic or Latino; Native Hawaiian or Pacific Islander; or white), educational attainment, estimated yearly income, and health insurance coverage.
Sexual risk was measured by items that assessed the frequency of condom use during oral and anal intercourse with a male partner within the past 3 months and the number of sex partners during the past 30 days and lifetime. Items assessed whether participants had ever received a positive HIV serological test result. Items also assessed whether participants had ever or in the past 5 years been told that they had HIV disease or any other STD.
Items measured nonsexual risk behaviors as well, including international travel since 1995, because HBV vaccination is recommended for travel within some regions. 50–52 Items assessed participant history of injecting drugs or steroids, sharing injecting-drug equipment, and receiving blood or blood products.
Items assessed participant history of HBV awareness, vaccination, testing, and treatment. Vaccination against HBV was assessed by self-reported vaccination status, regardless of completion of the three-dose series (data have suggested that an incomplete vaccination regimen may confer adequate immunity in some individuals). 53–55
Theory-based, latent construct variables based on the HBM and the social cognitive theory, specifically related to HBV vaccination, were measured with 34 items comprising eight measures that have been identified through rigorous psychometric scale development. In brief, measurement development with use of a diverse sample of 358 MSM followed a two-step process.
First, standard procedures of principal component analysis (PCA) with Varimax rotation were employed to determine a factor structure for each scale on a slit half sample (n = 179). The scree test, 56 eigenvalues, 57 interpretability of the factors, 58,59 theoretical considerations, 60 factor loadings, 56,58,61 and Cronbach’s coefficient alpha 62 were used to define all factor structures. The remaining split-half (“hold-out”) sample (n = 179) was used for instrument confirmation analyses with AMOS, 63 a statistical package that is commonly used for structural equation modeling (SEM).
Confirmatory factor analysis (CFA) via SEM recently has become one of the primary methods of choice for measurement development. CFA recognizes the role of theory for establishing a structural model that organizes scale and subscale development. CFA permits evaluating the adequacy of a proposed factor structure. 64–66 Number of items per scale, sample items, and Cronbach’s coefficient alphas for the current study sample are presented in Table 1.
A final item assessed whether participants had completed the questionnaire previously. The response categories for each item within the questionnaire used binary, categorical, or Likert-scale responses to facilitate readability and administration.
SPSS for Windows 10.1 (SPSS, Chicago, IL) was used for data analysis. The Kolmogorov–Smirnov one-sample test 57 was performed to determine whether the data were normally distributed. All distributions were normal at P < 0.05.
All theory-based scales were dichotomized by median split and entered into a multivariate logistic regression model to test the independent contribution of each of the constructs while adjusting for the other constructs in the model. 67 Accordingly, adjusted odds ratios (ORs) and 95% CIs were calculated to assess the magnitude of association between theory-based predictors and self-reported vaccination.
Of the 179 participants who completed the survey, 167 were identified as MSM; of these, 143 self-identified as black; 5 as Hispanic or Latino; 5 as Asian; and 4 as white. Of the 143 black participants, the mean (±SD) age was 25.18 ± 6.1 years, with a range of 18 to 50 years. The majority of participants reported some college or more education (62.9%), yearly income of $20,000 or more (61.7%), and having private health insurance (59.0%).
Nearly 42% (n = 60) reported being vaccinated against HBV, while 18.9% (n = 27) reported never having heard of HBV. Over half of the participants reported 10 or more different lifetime male sex partners (n = 92), and fewer than half reported 2 or more different male sex partners within the past 30 days (n = 61). Nearly a third (n = 47) reported having had intercourse with females as well as males within the past 5 years.
When asked what percentage of the time they used condoms during intercourse, 7% of the participants reported condom use over half of the time when performing or receiving oral intercourse, and 50% of the participants reported using a condom over half the time during insertive or receptive anal intercourse.
Not including HIV seropositivity, over 13% of this sample (n = 19) reported a lifetime history of at least one STD diagnosis, and 6.3% (n = 9) reported that they had received at least one STD diagnosis within the past 5 years. Almost 6% (n = 8) reported a positive HIV antibody test result. About 4% of the sample (n = 6) reported having received blood or blood products before 1992, and 5.6% (n = 8) reported ever having injected drugs or steroids; only two participants reported ever having shared injecting drug equipment.
Attitudes and Beliefs About HBV Infection and Vaccination
Table 2 displays the OR, 95% CI, and significance level between HBV vaccination and the independent contribution of each theory-based construct. The predictive power of the overall theory-based model (chi-square = 86.32;P = 0.0001) was high, correctly classifying 79% of the participants in their self-reported vaccination status categories.
Participants who perceived low levels of practical barriers to HBV vaccination were 2.7 times more likely to be vaccinated against HBV than those who perceived high levels of practical barriers to HBV vaccination. Participants who perceived the medical outcomes of HBV infection to be highly severe were 5.3 times more likely to self-report vaccination against HBV than those who perceived low levels of general medical severity, and those who perceived high levels of personal severity of HBV were 2.2 times more likely to self-report HBV vaccination. Participants who perceived high levels of general medical self-efficacy to complete the three-dose series were nine times more likely to self-report HBV vaccination than those who perceived low levels of general medical self-efficacy to complete the series, and participants who perceived high levels of personal self-efficacy to complete the three-dose series were twice as likely to self-report HBV vaccination than those who perceived low levels of personal self-efficacy.
Enhancing awareness and facilitating vaccination among populations at risk for HBV infection are urgently needed. Although more than 40% of participants in this study reported vaccination, almost 20% reported no information about hepatitis. Furthermore, many participants reported engaging in behaviors that put them and their sex partners at risk for HBV infection. Given that HBV transmission can result from mucous membrane exposure to infectious body fluids, including semen, 10 the low level of vaccination and the high levels of risk behaviors, such as inconsistent condom use, suggest that the failure to vaccinate this high-risk population is a missed opportunity to prevent disease.
Within our sample of black MSM, lower scores for perceived practical barriers to HBV vaccination were associated with HBV vaccination. Thus, interventions to increase vaccination among these MSM may focus on educating MSM about insurance coverage for vaccination, identifying locations for vaccination administration, and reducing the out-of-pocket expense of vaccination against HBV.
Unlike other studies that have found an association between HBV vaccination and health care provider communication about patients’ sexual orientation and risk, 12,22 in the current study we did not find this to be a significant predictor of HBV vaccination after accounting for the other predictors in the model. In part, this finding may be due to efforts to use social networks for vaccination efforts that do not require individual risk disclosure. Using the social networks of black MSM, promoters of vaccination services, such as health department staff, can reach eligible men for HBV vaccination without requiring sexual orientation or sexual risk disclosure. Using a diffusion-of-innovations 68 approach has been shown to be successful in HIV prevention intervention design among MSM 69,70 and could be tested empirically for the promotion of HBV vaccination, especially among men who may perceive social stigma associated with their same-sex behavior.
Furthermore, because recommendation by a health care provider has been found to be a strong predictor of preventive behavior in general, 71–73 the importance of the health care provider in promoting preventive behavior among MSM cannot be discounted on the basis of this study. In fact, the provider may influence other attitudes and beliefs that have been found to be predictive of HBV vaccination.
The finding that vaccinated participants perceived a higher level of severity of HBV infection reflects both medical and personal perceptions of severity. Because each subscale was included in the multivariable logistic model, efforts to increase vaccination rates among MSM must include messages that address the medical sequelae of HBV infection as well as the personal relevance of HBV infection (e.g., effects on diet and one’s peace of mind).
General medical and personal self-efficacy also was found to be predictive of vaccination status in the multivariable model. Participants who reported more confidence in overcoming fears of needles, fears of vaccinations, and their distrust for the government were more likely to report vaccination, as were participants who reported more confidence in overcoming the embarrassment of talking about their sexual behavior with providers, worries about HBV vaccine safety and possible side effects, and concerns such as time and money.
Thus, to increase vaccination among unvaccinated MSM, trust must be built between the medical community and the black MSM community in order to overcome histories such as the Tuskegee Syphilis Study and to ensure utilization of health-promoting technologies. The emphasis on vaccine safety also is particularly important, given the negative publicity surrounding potential deleterious side effects of the HBV vaccine. 74,75
The negative association between HBV vaccination and perceived susceptibility to infection may be a result of vaccinated individuals reporting low perceived susceptibility as a result of their vaccination status; those who have been vaccinated do not believe they are susceptible to infection on the basis of their vaccination status.
The current study is not without limitations. First, the observed associations are based on cross-sectional data. Additional studies with a prospective cohort design will be necessary to evaluate the significance and stability of these findings over time. Furthermore, the results of this study may not apply to the general population of MSM. However, the degree of fit between a sample and a target population about which generalizations can be made is a common challenge in many studies; in fact, nearly all studies of sexual behavior among MSM are based on nonrandom, self-selected samples. 76–78
Lending support for the validity of this study, the vaccination rate we observed is within the range of what other investigators have reported. 12,15,18–23 Although we utilized a self-administered format that may minimize response bias and included techniques found to increase validity of self-reported behavior, 79 these results nevertheless are based on self-reported data, with their potential limitations. 80
Understanding HBV vaccination among black MSM not only is crucial for the development and evaluation of tailored interventions aimed at increasing vaccination against HBV but also provides the framework for developing future vaccination strategies for conditions such as HIV disease and hepatitis C. Whereas we have reported on psychosocial predictors of HBV vaccination based on a sample of black MSM, a group about whom much behavioral data are lacking, 81,82 subsequent studies must explore further the potential impact of increased access to heath care; reduced costs for vaccination services; and vaccination opportunities in untraditional venues such as bars, bath houses, coffee shops, gyms, and house parties.
Hepatitis B is one of only two vaccine-preventable STDs (hepatitis A is the other), but after 20 years of HBV vaccine licensure, many MSM remain unvaccinated. Much is still unknown about the factors that influence MSM vaccination behavior. Focus must be placed on increasing our understanding of the factors that affect vaccination acceptance in order to develop innovative and well-tailored strategies to increase vaccination rates among MSM.
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