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S A Strathdee

Publications and source records attributed to S A Strathdee.

70 records · Page 4Linked to original sources
PubMed1996

HIV/AIDS mortality in Canada: evidence of gender, regional and local area differentials.

OBJECTIVE: To assess the impact of HIV infection and AIDS on mortality patterns in Canada with specific reference to gender and regional differentials and to other leading causes of death. DESIGN: Descriptive, population-based study. SETTING: Canada. PATIENTS: All persons for whom HIV/AIDS [ninth revision of the International Classification of Diseases (ICD-9) 042-044] was recorded as the underlying cause of death as reported to Statistics Canada between 1987 and 1992. For comparative purposes data was obtained on five other leading underlying causes of death including coronary heart disease (ICD-9 410-414), motor vehicle accidents (ICD-9 E810-E819), and suicides (ICD-9 E950-E959) in men and women, lung cancer (ICD-9 162) in men and breast cancer (ICD-9 174) in women. Population figures were obtained from Statistics Canada estimates. MAIN OUTCOME MEASURES: Age and cause-specific mortality rates, standardized mortality ratios (SMR), potential years of life lost (PYLL) before age 65 years, and life expectancy lost due to a select underlying cause of death. RESULTS: Over the period 1 January 1987 to 31 December 1992, 5546 deaths attributed to HIV/AIDS (5229 in men and 317 in women) were recorded in Canada. SMR for men were significantly higher than the national average in the cities of Vancouver, Toronto and Montreal, whereas those for women were significantly greater only in Montreal. Deaths from HIV/AIDS accounted for 3.6% of PYLL in men and 0.4% of PYLL in women. In 1992, HIV/AIDS was the third leading cause of male PYLL surpassing lung cancer. In the cities of Montreal, Toronto, and Vancouver HIV/AIDS was the leading cause of PYLL and was responsible for significant decrease in life expectancy at birth in men over the study period. CONCLUSIONS: HIV/AIDS has had considerable impact on mortality within Canada, principally among men and particularly in the cities of Toronto, Vancouver and Montreal.

Acquired Immunodeficiency Syndrome↗
PubMed1996

The epidemiology of HIV-associated Kaposi's sarcoma: the unraveling mystery.

Unraveling the mysteries associated with the etiology of KS is of tremendous public health significance. Whereas the introduction of prophylaxis has led to a decreased incidence of Pneumocystis carinii pneumonia, the incidence of KS has remained relatively stable and treatment of the HIV-infected KS patient remains a challenge. The last year has brought forth significant breakthroughs in KS research. Although KSHV has only recently been described, rapid progress is being made in understanding the role of this virus in the pathophysiology of the various forms of KS. It is too early to conclude whether KSHV is the elusive 'KS cofactor' or if all forms of KS share a common etiology, but it appears to be the single most plausible agent to be identified to date. Since all cancers are multifactorial in origin, it is likely that other host, environmental and possibly other viral cofactors could influence the risk of developing KS. The search for such cofactors must continue. Even if KSHV plays a central role, the exact mechanisms by which HIV and KSHV may interact to induce KS lesions, the tendency for KS to occur among homosexual men relative to other HIV transmission groups, and the reasons for the aggressive course of this neoplasm in HIV-infected persons remain to be determined. If a causal association can be established, KSHV could provide a model for the understanding of virus-induced neoplasia, like its cousin EBV. Although important questions regarding the specificity and temporality of KSHV and KS remain unanswered, the development and application of a sensitive serodiagnostic tool in longitudinal studies will be a crucial next step.

AIDS-Related Opportunistic Infections↗
PubMed1996

Summary of track C: epidemiology and public health.

AIM: To review Track C on epidemiology and public health. DESCRIPTIVE EPIDEMIOLOGY: Recent trends in the descriptive epidemiology are reported, for example, the rapid spread of HIV in certain Asian countries and the more precise insights in the spread thanks to subtyping of HIV-1 (and HIV-2). TRANSMISSION: There is now ample evidence that sexually transmitted diseases enhance the rate of transmission. Viral load in the plasma of the mother is highly predictive for perinatal transmission. PROGRESSION: Natural history studies have shown that true non-progressors are probably rare. Preliminary evidence indicates that the progression rate to AIDS and death does not differ by HIV-1 subtype. Some genetic factors are associated with the rate of disease progression and a few with susceptibility to HIV infection. INTERVENTIONS AND PREVENTION: Needle-exchange programmes as an intervention measure for injecting drug users were hotly debated and so were HIV (home) testing and counselling. Successes in prevention were reported from Thailand and Uganda, and also from small scale programmes.

Female↗
PubMed1995

Motivations for service volunteer involvement at Casey House AIDS Hospice.

Despite the fact that volunteers are an integral component of an AIDS hospice program, there are few studies describing the motivations they may have in choosing to become involved in an AIDS hospice such as Casey House Hospice in Toronto, Ontario, Canada. This study made use of existing mechanisms to track Casey House service volunteers. Volunteers completed questionnaires at the time of application, and at three months and one year following their orientation. Volunteers were asked to describe why they wished to volunteer at the hospice, what their expectations were, and what motivated them to remain involved as a volunteer. This study revealed that Casey House volunteers are motivated by a general desire to contribute, as well as a desire for interaction and personal growth, and to experience the Casey House model of care. However, many volunteers do not enter the program with predetermined expectations, and their motivations for involvement may not be consciously recognized. Major factors relating to their continued involvement are the support and sense of value they receive from staff and residents, as well as the intensity of their experiences. Since this report is part of an ongoing, prospective study of AIDS hospice volunteers, there will be an opportunity to examine some of these issues in more detail at a later date.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Access to health care and geographic mobility of HIV/AIDS patients.

OBJECTIVE: To determine the patterns and determinants of mobility in persons with HIV infection or AIDS on a population basis. DESIGN: Descriptive cross-sectional population health study. TARGET POPULATION: 650 full members (i.e., HIV-positive) of the Vancouver Persons with AIDS Society who were residents of British Columbia and who allow the society to include unsolicited material with their monthly newsletter. MAIN OUTCOME MEASURES: Migration history, access to HIV-related care at diagnosis, current and pre-HIV sociodemographic characteristics, and current health status. RESULTS: Two hundred and fifty-two persons living with HIV/AIDS participated in the study. At the time of the survey, the majority of subjects were male (94 percent), aged between 30 and 54 years (87 percent), and able to carry out daily activities without assistance (84 percent). The median time since the known date of HIV infection was 6 years. Access to care at diagnosis was associated in this population with being diagnosed in the largest metropolitan area in the province (OR = 2.14; 95 percent CI: 1.18, 3.87), a pre-HIV income of $30,000 or more per annum (OR = 0.49; 95 percent CI: 0.27, 0.89), a known date of diagnosis prior to 1990 (78 percent versus 64 percent; p = 0.019), and living in the same residence from the date of known HIV diagnosis to the date of the survey (63 percent versus 51 percent; p = 0.024). CONCLUSION: Although no definitive causal association can be provided by this cross-sectional analysis, our results clearly highlight several ways in which the need for treatment and care potentially affect where persons with HIV/AIDS choose to live.

Adult↗
PubMed1995

Quantitative measures of human immunodeficiency virus-specific antibodies predict progression to AIDS.

Studies examining specific antibodies directed against antigenic components of human immunodeficiency virus (HIV), as potential markers of progression to AIDS, have reported inconsistent results. We used reflectance densitometry and survival analysis to determine whether single quantitative measures of HIV-specific antibodies predicted progression to AIDS in a prospective cohort of 159 HIV-infected homosexual men. Lowered baseline levels of p24 antibody and p24/gp41 antibody ratio were independent predictors of progression to AIDS and retained statistical significance after simultaneously controlling for CD4:CD8 ratio, age, use of zidovudine, and clinical symptoms. Quantitative measures of p24 antibody and p24/gp41 antibody ratio warrant further study with regards to their clinical application as markers of HIV disease progression.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Is the human immunodeficiency virus-related Kaposi's sarcoma epidemic coming to an end? Insights from the Tricontinental Seroconverter Study.

A decline in the proportion of Kaposi's sarcoma among AIDS cases since the 1980s has been attributed to changes in sexual behavior among homosexual men and a decreasing exposure to a hypothesized Kaposi's sarcoma cofactor. Recent studies have shown that the incidence rate of Kaposi's sarcoma has remained relatively stable, which seems to argue against the hypothesis of a declining exposure to the putative cofactor. To examine this paradox, we evaluated the incidence of Kaposi's sarcoma, using Cox proportional hazard analyses, and performed a simulation to compare incidences of different AIDS outcomes among 407 homosexual men with documented dates of seroconversion. Our data show that men who seroconverted early in the epidemic did not progress faster to Kaposi's sarcoma than men who seroconverted more recently. A lower incidence rate of Kaposi's sarcoma would be expected among the latter group if exposure to the hypothesized cofactor is decreasing over time. The percentage of Kaposi's sarcoma among incident AIDS cases decreased over the years following seroconversion, but not over calendar time. This study demonstrates that the decline in the proportion of Kaposi's sarcoma among AIDS cases should not be interpreted as a decline in the incidence of Kaposi's sarcoma and that there is no evidence that a hypothesized Kaposi's sarcoma cofactor is declining over calendar time.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Use of pooling and outpatient laboratory specimens in an anonymous seroprevalence survey of HIV infection in British Columbia, Canada.

OBJECTIVE: To conduct an anonymous HIV seroprevalence survey to establish a baseline estimate of HIV seroprevalence in a general population; to evaluate serum pooling and alternative testing strategies as cost-saving measures. DESIGN: Prospective anonymous HIV seroprevalence study using outpatient laboratory specimens. SETTING: Two large non-hospital-associated outpatient chemistry testing laboratories in the major population centers in British Columbia, Canada. PATIENTS AND SERA: Leftover sera received for chemistry screen testing in outpatient laboratories were provided to the study after chemistry testing was completed. Those from patients aged < 15 and > or = 55 years were excluded. METHODS: Patient identifiers were erased from samples. Sera were pooled 10:1 and tested by viral lysate enzyme-linked immunosorbent assay (ELISA). Sera from HIV-positive pools were tested individually. All individual HIV-positive specimens were retested for verification of positivity using a recombinant protein ELISA. MAIN OUTCOME MEASURES: HIV seroprevalence rates were stratified by sex, age group, and geographic area; and costs of pooling and alternative algorithm strategy were compared with those of conventional methods. RESULTS: A total of 80,238 sera were collected from 66,658 individuals (53% women, 47% men). Of these, 276 men (88.3 per 10,000) and 24 women (6.8 per 10,000) were HIV-seropositive. The highest rates were in those aged 30-34 years, for both men and women. Using pooling and non-Western blot verification saved US$2.07 per specimen, or 80% of the cost for conventional testing. CONCLUSIONS: The anonymous outpatient laboratory setting is practicable to obtain a reasonable estimate of HIV seroprevalence rates in a general population. Such studies can be made cost-effective by pooling sera and using alternative confirmatory strategies.

AIDS Serodiagnosis↗
PubMed1995

Rectal gonorrhoea as an independent risk factor for HIV infection in a cohort of homosexual men.

OBJECTIVE: To determine whether certain sexually transmitted diseases are independent risk factors for HIV transmission in a cohort of homosexual men. METHODS: Eligible cases were identified as those who had seroconverted between November 1982 and November 1990. Two persistently HIV-seronegative control participants were randomly selected for each case from all participants who remained seronegative in November 1990. For cases, risk factor data were taken from an index visit which was defined as the first seropositive visit, while for controls these data were obtained from a matched visit which occurred within two months of the index visit for the corresponding case. Mantel-Haenszel methods and logistic regression were used to compare differences in risk factors for seroconversion between cases and controls. RESULTS: A total of 125 cases and 250 controls were eligible for this study. Cases were significantly more likely to have had reported any gonorrhoea (17% versus 6%; OR = 2.94; 95% CI: 1.51-5.73) or syphilis (7% versus 2%; OR = 3.78; 95% CI: 1.33-10.79) than controls during the seroconversion period. Multivariate logistic regression revealed rectal gonorrhoea to be independently associated with risk of seroconversion (odds ratio = 3.18; p = 0.044), whereas urethral gonorrhoea (p = 0.479) and pharyngeal gonorrhoea (p = 0.434) were not after inclusion of rectal gonorrhoea. In addition, the following variables were also shown to exert an independent effect on seroconversion: frequency of anal intercourse, use of illicit drugs, number of male sexual partners, and lack of a post-secondary education. CONCLUSIONS: In this observational study, rectal gonorrhoea was found to be associated with HIV seroconversion after adjustment for a number of HIV risk factors. We cannot rule out that rectal gonorrhoea was not directly associated with HIV infection but rather with other residual lifestyle factors not fully adjusted for in the analysis. However, the relationship with gonococcal involvement of a specific anatomic site lends support to a biological association between gonorrhoea and HIV infection, rather than to alternative non-biologic explanations. Our findings are consistent with previous studies reporting an association between HIV infection and non-ulcerative sexually transmitted diseases. Such a direct association might be explained by postulating that gonorrhoea results in inflamed rectal mucosa and compromised epithelial integrity, thereby predisposing an individual to subsequent HIV infection.

Adult↗
PubMed1994

Lower socioeconomic status and shorter survival following HIV infection.

We studied the association between socioeconomic status and survival in a prospective study of 364 HIV-infected homosexual men who were recruited during 1982-84. The participants were divided by annual income; those earning above Canadian $10,000 (high-income; n = 274) and those below $10,000 (low-income; n = 90) at recruitment. The latter threshold closely approximated to the poverty level for this population. Low income men were significantly younger than high income men but the groups were similar with respect to baseline CD4 counts, subsequent use of anti-retrovirals and prophylaxis against Pneumocystis carinii pneumonia (PCP), and number of visits attended during follow-up. Subjects were followed for a median of 9.5 years (range 1.8-13.1). By Dec 31, 1993, there were 135 deaths yielding a cumulative mortality rate of mean 45% (SD 4.0) at 11.5 years. Men aged 30 or more at infection had poorer survival than those under 30 (mortality risk ratio 1.56; 95% CI 1.09-2.24; p = 0.015), and longer survival was significantly associated with a higher CD4 count at the earliest seropositive visit. The age-adjusted mortality risk ratio for low income men compared with high income men was significantly increased at 1.63 (95% CI 1.11-2.40; p = 0.013). The significant risk of death for low income men persisted despite adjustment for age at infection, CD4 count, use of zidovudine, dideoxyinosine, and dideoxycytidine, use of PCP prophylaxis, and year of infection. We cannot attribute our findings to income loss as a result of more rapid HIV progression because the same effect was present in people who provided income data before seroconversion. Similarly, our findings are not due to differential access to care because the study was done within the context of a universal health care system, and the two income groups received treatments equally. This finding is consistent with the association of lower socioeconomic status with increased morbidity and mortality observed within large populations and in other diseases.

Acquired Immunodeficiency Syndrome↗
PubMed1994

The changing spectrum of AIDS index diseases in Canada.

OBJECTIVE: To describe the changing spectrum of AIDS index diseases in Canada over a 10-year period from 1981 to 1991. DESIGN: A descriptive, population-based study. SETTING: Canada. PATIENTS: All cases of AIDS in Canada reported by the Division of HIV/AIDS Epidemiology of the Department of National Health and Welfare. MAIN OUTCOME MEASURES: Age-standardized rates of initial AIDS manifestations (1987 Centers for Disease Control and Prevention case definition), by year of diagnosis among adults in Canada. RESULTS: A total of 6641 adult AIDS cases were examined. The rate of Pneumocystis carinii pneumonia (PCP) peaked in 1989 with a rate of 3.18 per 100,000, declining to 2.74 per 100,000 in 1991 (P = 0.894). Similarly, the rate of Kaposi's sarcoma (KS) stabilized during this interval from 1.06 per 100,000 in 1987 to 1.14 per 100,000 in 1991 (P = 0.189). In contrast, the rates of all other AIDS-defining illnesses increased from 1.48 per 100,000 in 1987 to 3.43 per 100,000 in 1991 (P = 0.001). For these other AIDS index diseases, significant rate increases were observed for esophageal candidiasis, cytomegalovirus (CMV) diseases, wasting syndrome, toxoplasmosis, and Mycobacterium avium complex (MAC) disease. CONCLUSIONS: Our study shows a leveling and decline in incidence of KS and PCP, respectively, and a concomitant increase of other diagnoses, especially esophageal candidiasis, CMV, wasting syndrome, toxoplasmosis, and MAC disease in Canada. These findings highlight the importance of developing specific strategies to prevent emerging AIDS index diseases and serve as a cautionary note to practicing clinicians, indicating the relative widening of the spectrum of HIV index diseases.

AIDS-Related Opportunistic Infections↗
PubMed1994

Increasing age is associated with faster progression to neoplasms but not opportunistic infections in HIV-infected homosexual men.

OBJECTIVE: To characterize the associations of age and progression rates to AIDS-defining neoplasms and opportunistic infections (OI) in HIV-infected homosexual men. METHODS: Data from 407 homosexual men with documented dates of HIV seroconversion participating in cohort studies from four geographic locations were merged. Kaplan-Meier and Cox proportional hazards analyses were conducted with respect to the association of age with time from seroconversion to the first AIDS-defining neoplasm and OI. RESULTS: Among the 407 participants, 139 (34%) were diagnosed with AIDS; 45 (11%) with neoplasms and 90 (22%) with OI. Older age at seroconversion was significantly associated with faster progression to neoplasms, but not to OI. For each 10-year increase in age the risk for neoplasms increased 1.65-fold [95% confidence interval (CI), 1.12-2.43], after adjustment for clinical treatments. For OI this risk estimate was 0.98 (95% CI, 0.72-1.34). CONCLUSIONS: Increasing age is associated with faster progression to AIDS-defining neoplasms, but not with progression to OI. This has not been previously reported and may explain conflicting results in other studies among homosexual men that considered AIDS as a single entity. Our findings suggest that age and AIDS manifestations should be considered, particularly in the context of natural history studies, clinical trials and mathematical modelling.

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

Non-nominal HIV surveillance: preserving privacy while tracking an epidemic.

OBJECTIVE: To enhance HIV surveillance within a non-nominal provincial testing system. METHODS: Confirmatory HIV tests from a provincial laboratory were analyzed during 1995 and 1996. Enhancements included elimination of repeat positive tests for the same individual using automated matching of non-nominal identifiers and nurse call-back of health care providers, completion of missing information through call-back and connection of providers with resources for patient care. RESULTS: Forty-seven percent of 2,683 reactive HIV tests were identified as duplicates for the same individual, meaning that 1,401 people tested positive for the first time. From laboratory test data to enhanced unduplicated data after call-back, the proportion of tests for which risk and ethnic information was unknown dropped from 37% to 11% and from 64% to 18% respectively (p < 0.0001). CONCLUSIONS: Enhanced non-nominal surveillance for HIV is a practical means of marrying the needs of public health for epidemiological information and the rights of patients to privacy.

AIDS Serodiagnosis↗
PubMedDate not supplied

Determinants of HIV-related high risk behaviours among young offenders: a window of opportunity.

PURPOSE: To study HIV-associated risk behaviours among young offenders. METHODS: Juveniles aged 12 to 19 years entering correctional facilities in British Columbia volunteered in an unlinked anonymous study. Logistic regression was used to identify factors associated with high-risk sexual behaviours and injection drug use (IDU). RESULTS: Despite low HIV prevalence (0.25%), patterns of risk behaviour were evident. IDU and homosexual/bisexual activity were equally prevalent among youth aged 12 to 15 and 16 to 19 years. For both age groups, IDU and female gender were significant predictors of sex for trade and sex with another drug user. Natives aged 12 to 15 years were five times more likely to inject drugs than non-Natives. However, predictors of IDU differed for older vs. younger youth. CONCLUSIONS: Patterns of high-risk activity begin early and selective pressures may differ for younger vs. older young offenders. Youth in detention provide a window of opportunity for enhanced HIV/AIDS education.

AIDS Serodiagnosis↗