Risk of HIV infection in homosexual men
BMJ (British Medical Journal), 1993, 307: 681 (letter).
Authors: PM Davies, P Weatherburn, FCI Hickson, PG Keogh
Letter - full text
Editor, A recent paper from the Communicable Disease Surveillance Centre has been widely interpreted to show that younger homosexually active men are more at risk from HIV infection than older men,1 although the claim has subsequently been questioned by the first author (B Evans, personal communication). Evidence from clinic and surveillance data is subject to a number of biases, 2 including differing patterns of presentation at clinics. Claims that younger gay men have more risky behaviour patterns require evidence from sources other than clinics.
On 19 June 1993 an estimated 130 000 men and women assembled in south London after the Lesbian and Gay Pride March. We used the opportunity to distribute short questionnaires on sexual behaviour for self completion and administration by trained volunteers. Assessment of age trends was made with ANOVA; cross tabulation was by 10 groups (<21; age pairs to 34; 35-40; >40); and five year bands (<21; 21-25, 26-29; 30-34; 35-40; >40).
In all, 1633 usable questionnaires were returned; most were self-completed (1383). Median (mean) age was 28 (30), range 14-72. A total of 91 (5.6%) were under 21 years of age and 485 (29.7%) under 26; 86.2% of respondents claimed a gay identity.
Table I - Percentage of homosexual men reporting sexual contact and anal intercourse in the year before interview
|Regular partners||Casual partners|
|Sexual contact||88.1 (1393/1581)||69.5(1084/1560)|
|Anal intercourse||68.0 (1110/1580)||38.6(612/1579)|
|Without condom||28.3 (466/1597)||8.9(143/1591)|
|Without condom with >1 partner||5.0 (80/1597)||3.5(55/1591)|
Table II - Sexual experience of 1575 homosexual men who responded to questionnaire
|No||Mean Age||Years sexually active||Years since first anal intercourse|
|No anal intercourse||295||30.7||13.2||11.3|
|All with condom||422||29.5||13.5||10.8|
|1 without condom||136||29.4||13.6||10.7|
|All without condom||163||29.6||14.1||10.8|
The Table shows the proportions reporting anal intercourse in the preceding year with regular or casual partners in the whole sample. There were no significant age effects on any proportions and no effect of age on partner numbers.
All respondents were allocated to one of seven categories (table II) on the basis of their sexual behaviour in the past year. There were no significant age effects when age was taken as continuous or categorical (0.67 >p>0.10). Length of sexual career (years since first sexual encounter) also produced no significant result (p = 0.15).
Young men remain at risk of HIV transmission, but they are not more likely to have unsafe sex (on a number of measures) than older men. Unsafe behaviour occurs across the age range. Given the fact that homosexual contact remains the most common source of new HIV infection, 3 the need for targeted campaigns for all gay men remains immediate and pressing.
1 Evans BG, Catchpole MA, Heptonstall J, Mortimer JY, McCarrigle CA, Nicoll AG, et al. Sexually transmitted diseases and HIV-1 infection among homosexual men in England and Wales. BMJ 1993; 306:426-8.
2 Hunt AJ, Christofinis G, Coxon APM, Davies PM, McManus TJ, Sutherland S et al. Seroprevalence of HIV-1 infection in a cohort of homosexually active men. Genitourinary Med 1990;66: 423-7.
3 Public Health. Laboratory Service AIDS Centre and Communicable Diseases (Scotland) Unit. AIDS/HIV Quarterly Surveillance Tables: Data to end December 1991. 1991; No 14.