Renal effects of amlodipine in normotensive renal transplant recipients.

Renal effects of amlodipine in normotensive renal transplant recipients. The use of cyclosporin A (CsA) has improved the success of renal transplantation, but is associated with hypertension and significant renal toxicity. Previous reports suggest that calcium channel blockers may be useful in opposing the adverse effects of CsA. We have evaluated the effects of amlodipine (5 mg, once daily for 8 weeks) on renal function in 27 normotensive renal transplant recipients with stable renal function, in a double-blind, placebo-controlled, multicentre, cross over study. Amlodipine significantly reduced serum creatinine concentration relative to placebo (mean+/-SD: 168+/-65 vs 177+/-66 micromol/l; P=0.002) and there was a strong trend towards an increase in effective renal plasma flow on amlodipine relative to placebo (238+/-92 vs 217+/-87 ml/min; P=0.055). Glomerular filtration rate and lithium clearance were unaffected. Trough CsA blood concentration was unaffected. Amlodipine was well tolerated, with a low incidence of adverse events, and did not affect blood pressure or heart rate. In conclusion, amlodipine reduced serum creatinine in normotensive renal transplant recipients after only 8 weeks treatment, and was well tolerated in concomitant administration with CsA.

Partner notification for sexually transmitted diseases: proposed practice guidelines.

Using the results of an analysis of available scientific evidence and a survey of current practice in Canada, as well as expert opinion, these guidelines attempt to consider current partner notification practice in Canada and recommend an approach to determining practice which is flexible enough to address local circumstances. Priority areas for future research were also identified.

A survey of public health partner notification for sexually transmitted diseases in Canada.

OBJECTIVE: To describe the range of practice for sexually transmitted disease (STD) contact tracing/partner notification (PN) by public health agencies in Canada. METHODS: A two-level mailed survey, using two different questionnaires, was conducted from Aug. 1991 to Feb. 1992, directed to: 1) provincial and territorial epidemiologists/directors of STD control, asking about program organization; and 2) 154 local health units/provincially run PN programs, asking about practice patterns of STD partner notification. CONCLUSIONS: In Canada, STD PN by public health agencies is routinely practised in most provinces. PN efforts vary by the STD; less PN effort goes to chlamydia despite a high burden of illness; HIV PN is frequently perceived to be within the responsibility of the physician. For STDs with higher PN effort, the preferred method is provider referral. Targeting is seldom utilized, and there are little available data at a local level monitoring even process measures of effectiveness.

Ongoing high-risk sexual behaviors in relation recreational drug use in sexual encounters. Analysis of 5 years of data from the Toronto Sexual Contact Study.

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.

Recurrent themes of concern in groups for health care professionals.

This paper reports of recurrent themes of concern about AIDS expressed by health care professionals participating in small group sessions. Three dominant themes emerged: fear of contagion, homophobia, and attachment and loss. For each of these themes the possible meanings are explored. Fear of contagion was the dominant theme and is discussed as both a possible expression of displaced homophobia and a 'catastrophic' risk factor (extreme negative consequence). The need of health care professionals to see themselves as 'different' from the person with AIDS is also discussed. Professionals also discussed the emotional burden of caring for young patients often similar in age to themselves. It is suggested that hospital policy makers need to accept the reality of staff concerns and provide adequate forums for expression of concerns since without an opportunity for thoughtful discussion, health care professionals may espouse the 'correct' position and attitude, but believe and practise something else.

Varied potential risks of HIV infection among prostitutes.

To date, most HIV prevention programs targeting North American prostitutes have focused on individual behaviour change, and in particular, the consistent use of condoms between prostitutes and their clients. The organizational and societal level issues which may influence high risk practices within the working and private spheres have received relatively little attention. In addition, most prevention efforts have been limited to targeting the sub-population of street prostitutes. We outline here three different types of prostitutes (street prostitutes, escorts, and prostitutes who work part time in the service sector, i.e. barmaids and erotic massage therapists) known to work in many North American centres. In doing so, we suggest that potential risks of infection vary according to the type of prostitution, and that prevention programs must recognize the diversity in potential risk practices. Differences in the organization of work and working conditions of varied types of prostitutes may, in particular, influence risk practices while working. Some of the individual, organizational and societal level issues which influence risk practices among different types of prostitutes are presented. Much of the research involving HIV and prostitutes has accessed prostitutes at sites where street prostitutes are over-represented. Other studies are based on potentially baised samples as they have recruited prostitutes from medical clinics. Methodologic problems that influence attempts to obtain a representative sample of the prostitute population are discussed.

An efficacy trial of a mammalian cell-derived recombinant DNA hepatitis B vaccine in infants born to mothers positive for HBsAg, in Shanghai, China.

We conducted a randomized, double-blind clinical trial of an experimental mammalian cell-derived DNA hepatitis B vaccine (Betagen, Connaught Laboratories Ltd, Toronto, Canada) to determine its efficacy in infants born to mothers who were carriers of hepatitis B surface antigen (HBsAg). Four groups of 55 infants received injections as follows: (1) a licensed plasma-derived vaccine (Lanzhou, Lanzhou Institute for Biological Products, Lanzhou, People's Republic of China), 20 micrograms; (2) Betagen, 20 micrograms; (3) Betagen, 20 micrograms+hepatitis B immune globulin (HBIG); and (4) Betagen, 10 micrograms+HBIG. Vaccine injections were given at birth and at 1 and 6 months and HBIG was given at birth. The vaccines were compared to a historical placebo control group. The efficacy of Betagen alone was 82.6% compared to 51.0% for the Lanzhou. Efficacy of Betagen increased with the concomitant use of HBIG. No infants who were HBsAg negative at birth and/or were born to hepatitis B e antigen (HBeAg) negative mothers became carriers. The rate of HBsAg in infants receiving Betagen alone, and born to mothers who were HBeAg positive, decreased from 60% at birth to 20% by the ninth month, compared to 62.5% and 50% (respectively) for Lanzhou. The percentage of infants with protective levels of antiHBs was significantly higher for Betagen alone than for Lanzhou, but the geometric mean titre of antiHBs for responders was not significantly different. We have shown that Betagen alone is highly efficacious in preventing the development of hepatitis B in infants born to mothers who are carriers of HBsAg and is also highly effective in reducing the carriage of HBsAg in infants who are HBsAg positive at birth and/or born to HBeAg positive mothers.

PIP: Researchers assigned 220 infants born at 5 participating hospitals in Shanghai, China to receive either a 20mcg of an experimental recombinant DNA hepatitis B vaccine (Betagen), a licensed plasma derived hepatitis B vaccine (Lanzhou), 20 mcg of Betagen and hepatitis B immune globulin (HBIG), or 10mcg of Betagen and HBIG to determine the efficacy of Betagen in infants born to mothers with hepatitis B surface antigen (HBsAg) positive. Since China is a hyperendemic hepatitis B carrier area (in Shanghai, for example, prevalence rate is 57%), China hopes to reduce the carrier state via a low cost, safe, immunogenic, and efficacious recombinant vaccine. 20mcg of Betagen resulted in 82.6% efficacy which was significantly higher than that of Lanzhou (51%). The efficacy increased when HBIG was administered with the 20mcg of Betagen (92%). None of the infants born HBsAg negative and/or born to hepatitis B e antigen (HBeAg) mothers later became carriers. Further the HBsAg positive fell from 60-2-% in 9 months whereas these corresponding figures for those who received only Lanzhou were 62.5% and 50%. Even though the percentage of infants with protective levels of antiHBs stood much higher in those who received only Betagen than for those who received Lanzhou in all the months of follow up, except the 1st, their geometric mean titre of antiHBs was not statistically significant. Since Betagen prompted a quick antibody response which probably helped decrease HBsAg in the serum of those infants already positive for HBsAg at birth, it had an advantage over Lanzhou. In conclusion, Betagen given alone proved to be very efficacious in preventing hepatitis B in infants born to carriers of HBsAg. Further it was effective in reducing carriage of HBsAg in infants born HBsAg positive and/or born to HBeAg positive mothers.

Using serial observations to identify predictors of progression to AIDS in the Toronto Sexual Contact Study.

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 enrollment 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 enrollment 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 enrollment were significantly associated with elevated risk.(ABSTRACT TRUNCATED AT 250 WORDS)

The Ontario HIV seroprevalence study of childbearing women: results from the first year of testing.

The Ontario HIV Seroprevalence Study of Childbearing Women is an unliked anonymous seroprevalence study designed according to the well-established ethical and legal guidelines for such studies. Commencing in November, 1989, randomly selected neonatal heelprick specimens were tested for the presence of HIV antibodies after all identifying information had been permanently and irrevocably unlinked from the specimens. During the first year of the study 94,119 (approximately 60% of all submitted specimens) were tested. Twenty-six specimens which were repeatedly reactive by EIA were confirmed as positive for an overall crude seroprevalence rate of 2.8 per 10,000 women having live births (95% CI: 1.8-4.1). Twenty-five of the 26 confirmed seropositive results came from babies born in hospitals in the Metropolitan Toronto, Ottawa-Carlton, or Hamilton-Peel-Halton regions.

The probability of progression to AIDS in a cohort of male sexual contacts of men with HIV disease.

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%.

Needle sharing behaviour among injection drug users (IDUs) in treatment in Montreal and Toronto, 1988-1989.

Injection drug users (IDUs) entering treatment programs in Montreal and Toronto were recruited for a study of drug using behaviour and risk of HIV infection. Only those who had injected within 6 months of entering their treatment program were eligible for participation. 183 subjects were recruited in Montreal and 167 in Toronto between November, 1988 and October, 1989. Each participant completed a standardized interviewer-administered questionnaire which focussed on, among other things, drug history and needle sharing behaviour. Approximately three-quarters of respondents in both cities reported sharing needles and syringes within the 6-month period prior to their entry into treatment. Our analysis, which focussed on variables associated with needle sharing revealed that having a sexual partner who injected, trouble obtaining sterile needles and syringes and cocaine injection were significantly and independently associated with needle sharing in a logistic regression model which also controlled for city of recruitment.

Fear of contagion and AIDS: nurses' perception of risk.

Nurses' fear of contagion when caring for persons with AIDS remains high despite increased levels of knowledge. This paper examines the multiple factors that contribute to nurses' perception of risk within the workplace. The authors suggests that constructs from theories such as decision making, psychoanalysis and cognitive psychology can provide insight into the assessment of risk. Findings from a recent survey of nurses are used to illustrate the complex nature of fear of contagion. Understanding this complexity may be an essential first step in order to provide opportunities for resolution of fears and modification of behaviors.

A randomized trial of group interventions for hospital staff caring for persons with AIDS.

The purpose of this study was to develop an educational package for health care providers. Findings from a survey conducted by investigators were used to direct intervention content. All subjects received a 1 hour educational package. Since this type of intervention was not expected to be sufficient to modify attitudes and concerns, 75% of the subjects received an additional 1 hour group discussion intervention (n = 118). In a subgroup of those receiving group interventions, the discussion was preceded by the presence of a person with AIDS (PWA) (in person or on video) discussing his personal experience with the illness and health care workers. It was demonstrated that in order to modify change attitudes, concerns, and affective response, groups were necessary. Furthermore, fear of risk of contagion and homophobia required the presence of a PWA (in person or on video) in order for change to occur.

The knowledge, attitudes and concerns of hospital staff about AIDS.

Staff from 3 Toronto hospitals were surveyed for knowledge, attitudes and concerns about AIDS. 70% of the 1,366 respondents had direct clinical experience with persons with AIDS. Data were analyzed according to hospital setting and professional group: physicians, nurses, technologists and supervisory staff. No setting difference was observed and although statistically significant differences (at the .001 level) were observed between professional groups, these differences are small and have little practical importance. In general, subjects answered 68% of the knowledge questions correctly. All attitudes and concerns were inversely associated to knowledge (Pearson r range was -.31 to -.20). Multivariate analysis demonstrated that knowledge and concern about contagion are important mediating variables (multiple r = .40) for other attitudes and concerns.

Sexual behaviour changes in a cohort of male sexual contacts of men with HIV disease: a three-year overview.

We describe the sexual behaviour reported by 240 seronegative and seropositive homosexual men over a 3-year period. Sexual partners of men with HIV disease were recruited into a prospective study between July 1984 and July 1985 and were monitored every 3 months thereafter. Data on sexual activities were collected through interviewer-administered questionnaires. The cohort experienced a reduction in both the number of sexual partners and the volume of sexual activity. Reductions in the number of partners were early and dramatic. Changes in sexual activities were gradual and consistent in trend. The greatest reduction occurred in high risk activities (receptive and insertive anal intercourse). After 3 years of follow-up, only 10% of the men continue to be exposed to semen through unprotected receptive anal intercourse and 18% through unprotected receptive oral-genital sex. The proportion of men engaging in oral-genital contact and masturbation remained stable over the 3 years. Once informed of their serostatus, both seropositive and seronegative men reduced their high risk behaviour. The decline in rates of STDs and seroconversion confirmed that this cohort had indeed reduced their high risk behaviour.

Comparison of saliva and blood for human immunodeficiency virus prevalence testing.

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.

Changing trends of cirrhosis mortality in Ontario, Canada, 1911-1986.

Cirrhosis mortality death rates in Ontario for ages 20 and over declined from a high of 9.3 per 100,000 in 1911 to a low of 5.6 per 100,000 in 1919 (p less than 0.001) and after a 17-year period of relative stability, rose steadily to a high of 19.7 per 100,000 in 1975 (p less than 0.0001) and then declined to 13.3 per 100,000 in 1986 (p less than 0.001). Rates were consistently higher for men than for women and the male to female ratio of the rates increased from a low of 1.3 in 1933 to a high of 2.5 in 1986. The rate of increase in the rates for both men and women, and the rate of decline after the mid 1970s was most noted in the younger ages. Differences in trend could not be related to changes in disease classification, method of recording deaths, changes in diagnostic habits such as introduction of needle liver biopsy or to method of standardizing the rates. There was a positive and significant correlation between per capita alcohol consumption and rates of cirrhosis in Ontario from 1932 to 1975. However, while cirrhosis rates declined markedly from 1976 to 1986, alcohol consumption remained stable from 1976 to 1980 and declined only slightly from 1981 to 1986. A possible explanation for lack of correlation between alcohol consumption and the cirrhosis rates from 1976 to 1986 could be that the balance of force favoured recovery i.e. those people who already had cirrhosis who decreased (or stopped) their consumption of alcohol, did not die. Correlations with lagged alcohol consumption could not explain all the changes in the cirrhosis rates. Although cirrhosis rates consistently increased with increasing age from 35 to 85, our results showed that succeeding generations were developing cirrhosis at successively younger ages after the age of 35. Possible explanations for this cohort effect are increased survival from infectious diseases in infancy and childhood, increase in hepatitis B infection, excessive drinking habits being established at younger ages or a change in the pathogenesis of the disease.

Comparison of three HIV antigen detection kits in sequential sera from a cohort of homosexual men.

HIV antigen detection kits are available from a number of commercial sources. Abbott, Coulter, and Du Pont antigen kits were used to test 661 sera collected sequentially from 65 members of the Toronto Sexual Contact Study (TSCS). The sera had been collected at 3-month intervals over 4 years from nine persistently HIV-seronegative men, 14 seroconverters, and 42 seroprevalent participants. Antigen was not detected in any seronegative men. Two of 14 seroconverters were antigen positive in the specimen immediately preceding seroconversion (by all kits). Antigen was detected in 22 of 56 seropositive participants; of these, 16 of 22 demonstrated the emergence of antigen during observation. Discrepancies were noted in the time of detection of antigen (ranging from 3 months to more than 3 years) in nine participants. Although overall concordance among all kits for all specimens appears high (95.4%), when the bias introduced by testing multiple specimens from the same patient is removed, the lower bound of concordance among all three kits is estimated to be 80%. Similarly, after correction, the upper and lower bound of estimates of sensitivity are Abbott 96, 92%; Coulter 88, 63%; and Du Pont 88, 58%. There are significant differences in the performance characteristics of these commercial products for the detection of HIV antigen in serum.

Cofactors of progression to acquired immunodeficiency syndrome in a cohort of male sexual contacts of men with human immunodeficiency virus disease.

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.