HIV risk factors and seroprevalence in surgical patients

To determine the prevalence of risk factors for human immunodeficiency virus (HIV) infection, and HIV-1 seroprevalence, in surgical patients.

Prospective study in which consenting patients completed a questionnaire on factors potentially related to a higher risk of HIV infection, and underwent an HIV-1 antibody test.

Both elective and emergency surgical admissions between July and November 1990 at St Vincent's Hospital, Sydney.

Of 1292 patients who were approached to participate, 27 had been previously diagnosed with HIV-1 infection and, of the remaining 1265, eight (0.63%) refused to answer the questionnaire and undergo a blood test, and 12 (0.95%) refused the blood test only. HIV-1 antibody testing was completed for 1171 study subjects. Twenty-six of the 807 men who answered the questionnaire had been previously diagnosed with HIV-1 infection. Of the remaining 781 male patients, 133 (17%) reported a history of homosexual contact, injecting drug use or blood transfusion, 132 (17%) had had a prior HIV-1 antibody test and three were newly diagnosed with HIV-1 infection as a result of the survey. Of 476 women who completed the questionnaire, one had been previously diagnosed with HIV-1 infection, and of the remaining 475, 59 (12.4%) reported injecting drug use or a blood transfusion and 72 (15%) had had a prior HIV-1 antibody test. No women were newly diagnosed with HIV-1 infection. Of patients reporting specific factors, the proportion who had had a prior HIV-1 antibody test varied from 62% for men reporting homosexual contact to 34% for recipients of a blood transfusion between 1980 and 1985.

Although an appreciable proportion of surgical patients admitted to St Vincent's Hospital reported factors associated with a higher risk of HIV infection, the prevalence of undiagnosed HIV-1 infection is very low, particularly among patients reporting no such factors.