© 1995 Oxford University Press
research-article |
Number of Sexual Partners, Condom Use and Risk of Human Immunodeficiency Virus Infection
*Istituto di Ricerche Farmacologiche ‘Mario Negri’ via Eritrea, 62, 1-20157 Milano, Italy
**Prima Clinica Ostertrica e Ginecologica, Università di Milano Milano, Italy
Servizio di Igiene e Medicina Preventiva USSL Lodi, Italy
Clinica Dermatosifilopatica, Università di Milano Ospedali Riuniti Bergamo, Italy
Centro per le Malattie a Trasmissione Sessuale Ospedale Civile di Brescia, Italy
Clinica Dermosifilopatica, Università di Verona Verona, Italy
¶Istituto di Statistica Medica e Biometria, Università di Milano Milano, Italy
#Servizio di Epidemiologia, Centro di Riferimento Oncologico Aviano, Pordenone, Italy
BACKGROUND: To analyse the relation between number of sexual partners, selected sexual habits and the risk of human immunodeficiency virus (HIV) infection.
METHODS: We conducted a case-control study nested in a cross-sectional survey conducted among subjects attending sexually transmitted diseases (STD) clinics in Northern Italy. Eligible for the study were 1711 subjects (1259 males, 452 females) who referred themselves for the first time between September 1988 and March 1993 to three STD clinics in Northern Italy for suspected STD or STD treatment. A total of 145 subjects (113 males and 32 females) were HIV positive.
RESULTS: In comparison with subjects reporting no or one sexual partner over the 3 years before the interview, the estimated odds ratios (OR) of HIV serum positivity were 1.2 (95% confidence interval [CI]: 0.6–2.3), 0.8 (95% CI: 0.4–1.8) and 0.3 (95% Cl: 0.4–2.5) In subjects reporting 2–3, 4–5, and 
6 partners, respectively. The results were simllar considering separately males and females and in men reporting only homosexual partners. Regular condom use decreased the risk of HIV infection: in comparison with subjects reporting no or occasional use of condoms, the OR of HIV infection was 0.5 (95% Cl: 0.4–0.8) for regular users. Considering men only, compared with men with no homosexual intercourse, the OR of HIV infection was 2.3 (95% Cl: 1.4–3.9) In those reporting bisexual intercourse and 2.2 (95% Cl: 1.2–4.2) In men reporting only homosexual intercourse (among homosexuals). There was no relation between HIV infection risk and receptive anal sex.
CONCLUSIONS: The risk of HIV infection does not increase linearty with the number of sexual partners in this population. This is reasonable, as the prevalence of HIV infection in this population is essentially determined by drug use. Caution is needed in the interpretation of these results since the analysis of role of number of sexual partners in male intravenous drug users is impaired by low statistical power.
Keywords sexual habits, risk factors, human immunodeficiency virus infection
Revised 1 May 1995