Poster presentation at the 11th annual BC AIDS Conference in November, 1998, in Vancouver, BC. (Originally presented at the XII International Conference on AIDS in July, 1998, in Geneva, Switzerland.)

Characteristics of Male Sex Trade Workers enrolled in a 
Prospective Study of HIV Incidence

Mary Lou Miller, RN; Steve Martindale; Steffanie A. Strathdee, PhD; Peter GA Cornelisse, MSc; Fiona Tetlock; James Tigchelaar; and Martin T. Schechter, OBC, MD, PhD; for the Vanguard Project, the University of British Columbia and the British Columbia Centre for Excellence in HIV/AIDS.

ACKNOWLEDGEMENTS:

The authors gratefully acknowledge the contributions of volunteer recruiter Garry Johnson; participating doctors and nurses, particularly James Tigchelaar of the Street Nurse Program; members of the Community Advisory Committee; Vanguard Project staff; and the study participants themselves. Artwork by John Ferrie. Tables created by Fiona Tetlock.

OBJECTIVE:

To compare demographics, sexual behaviours and drug use among male sex-trade workers relative to other gay and bisexual men in an ongoing prospective study.

BACKGROUND:

The Vanguard Project is a prospective study of HIV incidence and risk behaviours which began in May, 1995. Eligible participants are males between the ages of 18 and 30, living in the Greater Vancouver area, who have not previously tested HIV-positive. The study is open to all men who have sex with men, regardless of whether they self-identify as gay, bisexual or straight.

Recruitment of subjects involved outreach at gay community events, use of print materials (e.g. posters, brochures, condom packages), and recruitment by health care professionals at HIV testing clinics and local physicians' practices. Recruitment of street-involved sex-trade workers occurred primarily at an outreach clinic specifically aimed at street youth.

METHODS:

Study Design:

Eligible participants who provide informed consent complete an annual self-administered questionnaire and submit a blood sample for HIV antibody testing. The questionnaire includes information on demographics, sexual behaviour with both men and women, and psychosocial scales (e.g. 7-item Centres for Epidemiologic Studies depression scale [CES-D]).¹

For the purposes of this study, we defined "paid sex" in the questionnaire as: "Sex exchanged for money, drugs, goods, clothing, shelter or protection." The questionnaire also differentiated between "being paid for sex," and "paying someone else for sex." Respondents were asked whether they had ever engaged in these activities, and if they had done so in the year prior to baseline.

"Regular" partners were defined as men respondents had sex with "at least once a month," whereas "casual" partners were those they had sex with "less than once a month."

Statistical Analysis:

Prevalence of HIV infection and sexual and drug-using behaviours were determined for men who had completed a baseline questionnaire and HIV test as of May, 1998.

Contingency table analysis was used to compare characteristics of men who reported being paid for sex in the previous year, versus those who had not. All reported p-values are two-sided.

Among men who tested HIV-negative at baseline and returned for follow-up, HIV incidence density and corresponding 95% confidence intervals were calculated separately for men who had been paid for sex in the previous year versus the remainder of the cohort.

RESULTS:

Paid Sex:

As of May, 1998, baseline questionnaires and HIV test results were available for 681 men. As shown in Table 1, 165 participants (24%) reported ever having been paid for sex by another male, 13.5% in the previous year. Seventy two (11%) reported ever paying another male for sex, 3.5% in the previous year.

Socio-demographics:

Relative to the remainder of the cohort (n=589), men who were paid for sex in the previous year (n=92) were significantly younger and were more likely to be non-white (Table 2). Men being paid for sex were also less educated, had lower incomes and were more likely to report unstable housing. These men were also more likely to have been institutionalized in a psychiatric ward, to have high depression scores, and to have ever been incarcerated.

Sexual Experiences:

Men who had been paid for sex had engaged in consensual sex with males and females at younger ages, and were more likely to report currently having sex with both men and women (Table 3). These men were significantly more likely to report having sex outside (e.g. in parks). They were also more likely to have paid another male for sex, relative to the rest of the cohort. Finally, men who had been paid for sex were significantly more likely to report a history of sexual abuse, especially as a child. Four of these men reported having been raped in jail.

Substance Use:

Men who had been paid for sex were significantly more likely to report use of most recreational drugs, including injection drugs (Table 4).

Risk Behaviours:

As seen in Table 5, men being paid for sex were more likely to use condoms for oral sex with regular partners compared to the remainder of the cohort, but rates of unprotected anal sex were similar.

With casual male partners (Table 6), male sex-trade workers were also more likely to use condoms during oral sex; however, relative to the rest of the cohort, they were significantly less likely to report using condoms during anal insertive sex.

A disturbing finding was that with clients, 19% reported being paid more to have sex without condoms.

HIV Prevalence and Incidence:

HIV prevalence and incidence were much higher among men who had been paid for sex, relative to the remainder of the cohort (Table 7).

LIMITATIONS:

1. Small sample size contributed to low statistical power.
2. Definition of "sex trade" used was overly broad and therefore results may not be generalizable.
3. Limitations of the survey instrument did not allow for differentiation between sex trade clients and regular/casual sex partners.
4. Differential follow-up may have caused HIV incidence to be underestimated.

CONCLUSIONS:

Our analysis indicates that male sex-trade workers are vulnerable to HIV infection due to unfavourable living conditions, high levels of unprotected anal sex, and high rates of recreational drug use.

The high rate of injection drug use (IDU) is of particular concern due to a recent HIV outbreak among the IDU community in Vancouver.²

Many male sex-trade workers may not be reached through conventional prevention programs as many do not self-identify as gay. Prevention programs should also take into account the fact that for some male sex workers, economic need can compromise decisions surrounding safer sex. For these men, HIV/AIDS prevention must take into account their social, cultural, economic and sexual realities.

The fact that men being paid for sex were more likely to use condoms for oral sex relative to the rest of the cohort is encouraging, and suggests that behaviour change can be attained. However, since rates of unprotected anal sex were similar to the rest of the cohort, it is clear that education needs to be reinforced.

Table 1: [back to text]

Table2: [back to text]

Socio-Demographics

	Sex Trade Workers (n=92)	Rest of Cohort (n=589)
Median age	23 yrs [IQR: 20-26]	26 yrs [IQR: 23-28]
Non-white	41 (45%)*	147 (25%)
< high school education	37 (40%)	65 (11%)
Live in unstable housing**	43 (47%)	24 (4%)
Earn less than $10K/yr	55 (60%)	153 (26%)
Ever in psychiatric ward	25 (27%)	24 (4%)
High depression score***	41 (45%)	124 (21%)
Ever in jail	44 (48%)	29 (5%)

NB: all p-values <0.001
* Of the 92 men, 30% were Aboriginal, 7% Asian and 3% Black.
** Defined as living primarily in a hotel or transition house, on the street or in jail.
*** CES-D score above 75th percentile.

Table 3: [back to text]

Sexual Experiences

	Sex Trade Workers (n=92)	Rest of Cohort (n=589)	p-value
Age at 1st sex with MALE	15 yrs [IQR: 13-18]	18 yrs [IQR: 16-20]	<0.001
Age at 1st sex with FEMALE	15 yrs [IQR: 12-17]	17 yrs [IQR: 15-19]	<0.001
Sex with both men & women	45 (49%)	41 (7%)	<0.001
Sex outside*	68 (74%)	306 (52%)	<0.001
Paid someone else for sex*	9 (10%)	12 (2%)	0.002**
Non-consensual sex (ever)	47 (51%)	183 (31%)	0.001

* Since last visit.
** Fisher's exact test.

Table 4: [back to text]

Substance Use
in previous year

	Sex Trade Workers (n=92)	Rest of Cohort (n=589)
>10 drinks/wk	29 (32%)	77 (13%)
Poppers	45 (49%)	159 (27%)
Coke	55 (60%)	141 (24%)
Crack	29 (32%)	18 (3%)
Heroin	22 (24%)	18 (3%)
Injection drugs	25 (27 %)	24 (4%)

NB: all p-values <0.001

Table 5: [back to text]

Unprotected Sex with REGULAR Male Partners
in previous year

	Sex Trade Workers (n=92)	Rest of Cohort (n-589)
Oral insertive*	49 (53%)	430 (73%)
Oral receptive*	51 (55%)	430 (73%)
Anal insertive	22 (24%)	171 (29%)
Anal receptive	27 (29%)	177 (30%)

*p<0.1

Table 6: [back to text]

Unprotected Sex with CASUAL Male Partners
in previous year

	Sex Trade Workers (n=92)	Rest of Cohort (n-589)
Oral insertive*	55 (60%)	401 (68%)
Oral receptive*	58 (63%)	418 (71%)
Anal insertive**	22 (24%)	82 (14%)
Anal receptive	13 (14%)	71 (12%)

* p=0.01
** p<0.01

Table 7: [back to text]

HIV Incidence and Prevalence

	Sex Trade Workers (n=92)	Rest of Cohort (n=589)	Total
HIV Prevalence	5.56% [CI: 0.82-10.29]	1.53% [CI: 0.54-2.52]	2.06% [CI: 0.99-3.13]
HIV Incidence (per 100 person years)	9.53% [CI: 1.18-17.89]	1.02% [CI: 0.20-1.84]	1.72% [CI: 0.70-2.74]

1. Mirowsky J , Ross CE. Age and Depression. J Health Soc Behav 1992, 33: 187-205.
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2. Strathdee SA, Patrick DM, Currie S, Cornelisse PGA, Rekart ML, Montaner JSG, Schechter MT, O'Shaughnessy MV. Needle exchange is not enough: Lessons from the Vancouver Injection Drug Use Study. AIDS 1997, 8: F59-F65.
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