Gender, Race, Class and Self-Reported Sexually Transmitted Disease Incidence.(Statistical Data Included)

Multivariate analysis of data from two nationally representative surveys of adult men and women indicates that the likelihood of a self-reported sexually transmitted disease (STD) infection varies by gender, race and socioeconomic status, even after accounting for differences in sexual and health care behaviors. Women and black respondents are more than three times as likely to report an STD infection as men and white respondents; men and women with 12 or fewer years of education are about 30% less likely than those with more schooling to report having had an STD. Income, welfare status and access to health care have no significant association with self-reported STD incidence, but sexual behavior is strongly related. Men and women who have engaged in anal intercourse, have paid for sex or have had one-night stands are significantly more likely than those who avoid these behaviors to report an STD. Further, the likelihood of an STD dramatically increases with the lifetime number of sex partners reported: Compa red with men and women who have had only one partner, those who report 2-3 partners are five times as likely to have had an STD; the odds are as high as 31:1 for those who report 16 or more partners.

(Family Planning Perspectives, 27:196-202, 1995)

Sexually transmitted diseases (STDs) are a major public health problem in the United States, generating societal costs in excess of $3.5 billion annually. (1) During the last decade, both the number of STDs and their complexity have increased dramatically; more than 50 organisms and syndromes are now recognized. Although many of these diseases have long been known, others have recently achieved prominence because new diagnostic methods have helped investigators to describe their extent, method of transmission and clinical consequences.

STDs affect almost 12 million Americans each year, and nearly 50 million Americans may already have acquired viral STDs, which are not curable and infect the individual for life. (2) Gonorrhea is the most frequently reported STD; almost 700,000 cases were reported in 1990. Chlamydia is another common sexually transmitted bacterial pathogen; no formal surveillance system exists, but estimates derived from a variety of sources suggest that 3-4 million persons are infected with chlamydia annually. (3)

Women bear disproportionate consequences from gonorrhea and chlamydia because of the risk of pelvic inflammatory disease (PID), which often leads to such adverse sequelae as infertility and ectopic pregnancy. Some bacterial or viral STDs may affect infants either in utero or at birth. Additionally, other population subgroups are at increased risk of STDs. STD infection is more prevalent among blacks than among members of other racial groups, and is more common among those of low socioeconomic status than among those of higher status. (4)

Race and socioeconomic status may be different manifestations of the same phenomenon, but this supposition has not been unequivocally demonstrated. In any case, these two characteristics are clearly related to adverse health conditions, including cancer, diabetes and cardiovascular diseases, as well as STDs and AIDS. (5) Gender, race and social class not only influence risk behaviors, but also are presumed to affect the efficiency of transmission of some STDs, the ease with which infection is detected and care-seeking behaviors. (6)

In this article, we examine gender, race and class differences in the likelihood of ever having had an STD among a national sample of 20-37-year-old women and 20-39-year-old men.

Conceptual Framework

Three possible explanations may account for gender, race and class differentials in the distribution of STDs: differential biological disposition to acquiring certain diseases; differential sexual behaviors that increase the risk of infection; and differentials in preventive health behavior and access to and use of health care services. These explanations can be viewed in the context of a social-behavioral model that is based on the premise that STD acquisition is a function of the probability of exposure to infection, the probability of infection if exposed and the probability of disease if infected. (7)

The probability of exposure to an infected person is a function of both the number of new sex partners per unit of time and whether any given partner is infected. The latter is determined by the prevalence of infection within a community.

The probability that infection will occur after exposure is primarily a function of biological variables, including factors related to the pathogen, the infectiousness of the source and the susceptibility of the host. Behavioral risk factors, such as types of sexual behavior (e.g., anal vs. vaginal intercourse), frequency of sexual contact and preventive health care (e.g., use of condoms), also influence the likelihood of infection following exposure.

The probability that an infection will lead to a disease is influenced chiefly by health care--seeking behavior, which in turn is determined by such factors as the individual's willingness and ability to obtain health care services, as well as the availability, accessibility and cost of health care in the community. Once health care services have been obtained, compliance with therapy largely determines whether the infection will progress to a disease.

The behavioral risk factors are proximate determinants of STD acquisition, and they operate through the three parameters described above (exposure, infection and disease). We focus here on four risk factors related to sexual behavior (lifetime number of vaginal sex partners, engaging in one-night stands, exchanging sex for money or drugs, and engaging in anal intercourse) and two related to health care behavior (having a regular doctor and having health insurance).

Race has traditionally been tagged a risk marker for both sexual and health care behaviors.(8) For example, the onset of sexual activity is earlier among young black men and women than it is among whites. (9) Further, black men have a greater lifetime number of sex partners than men of other races. (10) It is also well documented that minority populations are characterized by poor health education, poor health care-seeking behavior, and poor access to diagnostic and therapeutic health services. (11) Additionally, because of the overall higher prevalence of STDs among the black population, and because there is a tendency toward selecting partners of the same race, blacks are at relatively high risk of STDs.

Socioeconomic status is thought to influence sexual behavior-specifically, to raise the likelihood of having multiple partners and engaging in a variety of sexual behaviors with those partners-for two reasons. First, education tends to have a liberalizing influence, promoting a more permissive sexual ideology among higher status men and women. (12) Second, higher status women and men are attractive mates because of their wealth, power and prestige. (13)

On the other hand, men and women of high socioeconomic status also have a greater sense of self-efficacy, better access to health care services and a higher likelihood of having health insurance coverage than those of lower status. (14) These characteristics promote the use of measures to prevent STD infection and of STD-related medical services. Further, men and women of high status tend to have low-risk sex partners because of class homogamy with respect to education, income and social class of origin, (15) and because high socioeconomic status is associated with relatively low STD rates. These factors are hypothesized to mitigate the positive influence of socioeconomic status and produce an overall negative relationship between class and the likelihood of STD infection.

Gender differences in STD rates are partly attributable to differences in the efficiency of transmission of some pathogens and the ease with which infection can be detected. (16) The difference in the efficiency of transmission results partly because the contact with pathogens after sexual exposure is more extended among women than among men. That is, if the male partner has an STD, the infected semen remains in the vagina following intercourse; in contrast, if the female partner is infected, the male's exposure to the pathogens is limited to the duration of coitus. The cervix may also be more susceptible to infection than the male's urethra. (17)

Furthermore, STDs are more difficult to detect in women than in men. For anatomical reasons, certain STDs may go unnoticed in women. Moreover, the large number and variety of cells and bacteria that are normally present in the vaginal vault…