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The current study investigated the association between the use of recreational drugs at the time of sexual activity and high-risk sexual behavior in a Toronto cohort of 249 homosexual and bisexual men over a 5-year period commencing in 1984 to 1985 and concluding in 1989 to 1990. The main analysis was based on a total of 2536 visits. Univariate and multivariate Liang-Zeger regression models were used to relate the log of the sexual activity score (SARS) to the independent variables over the 20 follow-up visits while controlling for intercorrelations between variables from the same respondent. We found that there was a significant decline, over time, in the sexual activities that pose a higher risk of infection with human immunodeficiency virus. Recreational drugs still appear to be playing an important role in the continuation of higher-risk sexual activities. The use of poppers in conjunction with sex is a strong predictor of high-risk activity, as is use of alcohol and marijuana in conjunction with sex. Also, simultaneously strongly associated with higher-risk score is the Centers for Disease Control classification II. More emphasis needs to be placed on educating the population about the potential risks of combining reactional drugs with sexual activity.

In a cohort of 249 male sexual contacts of men with acquired immunodeficiency syndrome (AIDS) or an AIDS-related condition in Toronto, Ontario, Canada, 143 cohort members were seropositive on enrollment and 16 seroconverted between initial recruitment in July 1984 to July 1985 and December 1988. Data on age, smoking and drinking status, recreational drug use, and history of sexually transmitted diseases and other diseases were obtained from interviews at induction and during follow-up on the cohort members every 3 months. Cox relative risk regression models, in which time was calculated from estimated date of human immunodeficiency virus (HIV) infection for seroprevalent cohort members and from 90 days prior to the first positive test for seroconverters, examined the potential effect of use of a variety of recreational drugs and the occurrence of selected infections on the risk of development of AIDS. Thirty-five cohort members developed AIDS while under study. No significant association with risk of progression to AIDS was noted for use of various recreational drugs (singly or in combination), history of specific infections, age at enrollment, or smoking and drinking status at enrollment. Only estimated duration of HIV infection appeared to be associated with increasing risk of development of AIDS.

The Toronto Sexual Contact Study comprises a cohort of 249 male sexual contacts of men with HIV disease which has been followed every 3 months for almost 5 years. On enrolment 143 were seropositive and 16 seroconverted during the follow-up period. By 31 December 1989,41 of the 159 seropositive cohort members had developed AIDS. Using Cox relative risk regression models, we investigated the association of a number of laboratory and clinical variables and progression to AIDS. Fixed covariate models examined laboratory variables from the enrolment visit of cohort members, with time calculated from this date. In models assessing time dependent covariates, time was calculated from the estimated date of HIV infection. In the univariate models of either fixed or time dependent covariates, many variables were significantly associated with risk of progression to AIDS (T4 cell count, T4/T8 ratio, blastogenic responses to phytohemagglutinin, concanavalin A, and pokeweed mitogen, serum IgA, appearance of p24 antigen, and the development of oral hairy leukoplakia, thrush, or herpes zoster). Appearance of persistent generalized lymphadenopathy was not associated with increased risk of progression. In the multivariate model which evaluated fixed laboratory covariates, T4/T8 ratio, IgA level, and PHA response at enrolment were significantly associated with elevated risk. In order to evaluate the impact of the serial observations of immune function variables, these variables were lagged one year in a model with other time dependent covariates; the following point estimates of relative risk of progression to AIDS were observed: for a unit decline in T4/T8 ratio, RR=60.8 ( p p = 0.07); for a 100 μg/l increase in IgA, RR=1.33, ( p = 0.02); for the development of oral hairy leukoplakia, thrush, or herpes zoster, RR=2.69, ( p = 0.02); and treatment with zidovudine, RR=0.06, ( p = 0.01).

In a cohort of 249 male sexual contacts of men with AIDS or an AIDS-related condition (ARC), 143 cohort members were seropositive on enrollment and 16 seroconverted during follow-up. A logistic Weibull mixture model was used to estimate the probability of progression to AIDS after HIV infection when infection was assumed to occur during the period of sexual contact with the primary case. Forty cohort members developed AIDS while under study. It appears that at least 50% of men with HIV disease will progress to AIDS and that the best estimate of this probability lies anywhere in the interval 70% to 100%.

To the Editor: In October 1998, the Centers for Disease Control and Prevention reported 20 endotoxin-like reactions to intravenous gentamicin1 administered in a once-daily dosing regimen. We report...

Testing saliva for the detection of human immunodeficiency virus (HIV) antibodies has many potential advantages for epidemiologic surveillance. A commercial ELISA kit and a standardized in-house immunoblot (IB) system were slightly modified to enhance antibody detection in saliva. Frozen saliva specimens from Toronto Sexual Contact Study participants (including sequential saliva specimens collected during seroconversion) were tested as were fresh saliva samples collected from a population of street-based intravenous drug users (IVDUs). HIV antibody results on saliva were compared with HIV serostatus determined by ELISA and IB on serum or dried blood spots. The overall sensitivity was 98.3% (117/119) for the kit and 99.2% (118/119) for IB; the specificity was 100% (429/429). In the IVDU population, compliance in the voluntary submission of specimens increased from 69% agreeing to provide blood samples to 89% agreeing to provide blood, saliva, or both. Saliva specimens can be easily collected under difficult field conditions with minimal training and provide a valuable alternative to testing blood for HIV-seroprevalence studies.

The degree of clinical agreement amongst different physicians on the presence or absence of generalized lymphadenopathy was assessed in 32 randomly selected participants from a prospective study of male sexual contacts of men with AIDS or an AIDS-related condition (ARC). Three physicians completed the same standard examination that was developed for the main project and conducted the examination of the anatomic regions in the same order on each person, at approximately the same time, and in random order. One physician (Doctor A) was the physician responsible for conducting examinations on the main cohort from which these participants were selected. Intra-observer agreement was assessed by comparing Doctor A's examinations on these participants with those he had recently conducted within a one and a half month period in the main study. Acceptable levels of intra-observer agreement (kappa = 0.72) and interobserver agreement (kappa = 0.66) were demonstrated for the presence or absence of generalized lymphadenopathy for Doctor A and Doctor B, a physician who periodically replaced Doctor A in the main project. Agreement between Doctors A, B, and C, was less satisfactory (kappa of 0.45 and 0.39, respectively). Doctor C was the least experienced with the standardized examination. However, during the progress of this study, agreement between the three doctors improved (kappa values for the latter 16 participants ranged from 0.60 to 0.86) suggesting that experience with the criteria and the standardization of the examination may enhance agreement.(ABSTRACT TRUNCATED AT 250 WORDS)

As part of a prospective study in Toronto, Canada of male sexual contacts of men with either acquired immunodeficiency syndrome (AIDS) or an AIDS-related condition (primary cases), separate interviews were conducted in 1984-1985 with primary cases and their corresponding sexual contacts. Seventy-five primary cases and their corresponding sexual contacts were asked details concerning the sexual activities involved in their sexual encounters. Spearman correlation coefficients were calculated for the responses regarding frequency of various sexual activities between the primary case and his corresponding contact. Comparison of responses revealed good to excellent correlations for the majority of the sexual activities. Regression analysis of responses (dependent variable = contact's response; independent variable = primary's response) revealed the tendency for primary cases to report greater numbers of various activities than sexual contacts, as illustrated by regression coefficients that were consistently less than unity. Agreement between primary responses and sexual contact responses appeared to be affected by the time lapsed from the last sexual encounter with the contact and the date of the primary case's interview. No effect on agreement was observed when primary case diagnosis and the total number of other sexual partners of primary cases were considered. The authors conclude that such data can be captured with sufficient reliability and validity for use in epidemiologic investigations to assess the risk of acquisition of human immunodeficiency virus for the more common forms of sexual activity. However, some caution may be necessary in interpreting the results for some activities (anal digit insertion, anilingus) since agreement is less satisfactory for these activities.

A total of 246 healthy male sexual contacts of men with either acquired immunodeficiency syndrome (AIDS) or an AIDS-related condition were recruited into a prospective study in Toronto, Canada between July 1984 and July 1985. At induction, data were collected on the sexual relationship between the contact and his primary case, sexual activities with other men, history of sexually transmitted diseases and other diseases, and use of recreational drugs. At recruitment, 144 sexual contacts had antibodies to human immunodeficiency virus (HIV); 102 of the contacts were seronegative at induction and at three months following recruitment. No association between HIV seropositivity and total number of sexual partners could be demonstrated. In univariate and multivariate analyses, receptive and insertive anal intercourse with the primary cases, and activities which either indicated or potentially caused anorectal mucosal injury (rectal douching, perianal bleeding, receipt of objects in ano, and receptive fisting) were strongly associated with HIV seropositivity. In the final multiple logistic regression model, two significant interaction effects were observed: the interaction between receptive anal intercourse and insertive anal intercourse and that between receptive anal intercourse and the anorectal mucosal injury index. These two interaction terms had negative regression coefficients which suggested that change in one sexual activity would not decrementally reduce risk of HIV infection without a comparable modification in the other activity. No association could be demonstrated between oral-genital and oral-anal sexual contact and odds ratios for these sexual activities declined to levels below 1.0 when adjusted for frequency of receptive anal intercourse.