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Evan Wood

Publications and source records attributed to Evan Wood.

103 records · Page 6Linked to original sources
PubMed2002

Socioeconomic status, access to triple therapy, and survival from HIV-disease since 1996.

BACKGROUND: In the era before highly active antiretroviral therapy (HAART), socioeconomic status was associated with survival from HIV disease. We have explored socioeconomic status, access to triple therapy (HAART), and mortality in the context of a universal healthcare system. METHODS: We evaluated 1408 individuals who initiated double or triple therapy between 1 August 1996 and 31 December 1999, and were followed until 31 March 2000. Cumulative HIV-related mortality rates were estimated using Kaplan-Meier methods and Cox proportional hazards regression. RESULTS: In the overall Cox model, we found that adherence [risk ratio (RR) 0.83; per 10% increase], CD4 cell count (RR 1.53; per 100 cell decrease), and lower socioeconomic status (RR 2.19; high versus low), were associated with HIV-related mortality. However, socioeconomic status was not significant among patients prescribed triple therapy in a stratified analysis, or in a sub-analysis restricted to patients prescribed HAART in the initial regimen. When we investigated if inequitable access to HAART by socio-economic status could explain the discrepancy, we found that persons in the lower socio-economic strata were less likely to be prescribed triple therapy even after adjustment for clinical characteristics. CONCLUSION: In a universal healthcare system, socioeconomic status was strongly associated with HIV-related mortality. When we investigated possible explanations for this association, we found that individuals of lower socioeconomic status were less likely to receive triple therapy after adjustment for clinical characteristics. Our findings highlight the need for the monitoring of therapeutic guidelines to ensure equitable access, as treatment strategies are updated.

Adult↗
PubMed2002

"Discordant" increases in CD4 cell count relative to plasma viral load in a closely followed cohort of patients initiating antiretroviral therapy.

BACKGROUND: In HIV-positive persons receiving antiretroviral therapy, CD4 cell responses are associated with optimal suppression of viral replication. However, increases in CD4 cell counts in the absence of viral suppression have been reported. We characterized plasma viral load (pVL) and CD4 cell count increases in closely followed patients to evaluate determinants and the prevalence of CD4 cell responses at a populational level. METHODS: All HIV-positive patients in the province of British Columbia, Canada, who were antiretroviral naive and initiated therapy between August 1996 and May 1998 were eligible for the study. The selection criteria were that patients had to have CD4 cell counts and pVLs measured at baseline and at least once during eight 16-week periods after the initiation of therapy. We characterized CD4 cell responses and sought patients who had a "discordant" increase at 1 year, which was defined as an increase in CD4 cell count of >or=50/mm3 with a <1 log10 decrease in pVL. We also evaluated adherence and antiretroviral use. RESULTS: Overall, when baseline and 1-year pVLs and CD4 cell counts were compared, 6.2% of patients had CD4 cell count increases without pVL decreases of >or=1 log10. However, when all pVLs before 1 year were considered, 92% of the discordant increases could be attributed to prior transient or partial viral suppression. Furthermore, although substantial increases in CD4 cell counts were observed in transient virologic responders, the cumulative number of antiretroviral agents used by this group was significantly higher than that used by full virologic responders (p <.001). CONCLUSIONS: Our results demonstrate that virtually all CD4 cell count increases can be attributed to transient or partial pVL suppression. Unmeasured pVL suppression likely explains discordant responses that have been previously reported. Similarities between transient and full virologic responders also appear to be time limited and are often associated with greater cumulative use of antiretroviral therapy by transient virologic responders.

Adult↗
PubMed2002

Factors associated with persistent high-risk syringe sharing in the presence of an established needle exchange programme.

Vancouver has experienced an explosive HIV epidemic despite the presence of a needle exchange programme (NEP). We sought possible explanations for high-risk syringe sharing among Vancouver injection drug users over the period January 1999 to October 2000. Overall, 14% of participants reported high-risk sharing. Although acquiring needles exclusively from the NEP was independently associated with less sharing, we identified several risk factors for persistent sharing, including difficulty accessing sterile needles, bingeing, and frequent cocaine injection.

British Columbia↗
PubMed2002

Risk factors for elevated HIV incidence rates among female injection drug users in Vancouver.

BACKGROUND: In 1997, we found a higher prevalence of HIV among female than among male injection drug users in Vancouver. Factors associated with HIV incidence among women in this setting were unknown. In the present study, we sought to compare HIV incidence rates among male and female injection drug users in Vancouver and to compare factors associated with HIV seroconversion. METHODS: This analysis was based on 939 participants recruited between May 1996 and December 2000 who were seronegative at enrolment with at least one follow-up visit completed, and who were studied prospectively until March 2001. Incidence rates were calculated using the Kaplan-Meier method. The Cox proportional hazards regression model was used to identify independent predictors of time to HIV seroconversion. RESULTS: As of March 2001, seroconversion had occurred in 110 of 939 participants (64 men, 46 women), yielding a cumulative incidence rate of HIV at 48 months of 13.4% (95% confidence interval [CI] 11.0%-15.8%). Incidence was higher among women than among men (16.6% v. 11.7%, p = 0.074). Multivariate analysis of the female participants' practices revealed injecting cocaine once or more per day compared with injecting less than once per day (adjusted relative risk [RR] 2.6, 95% CI 1.4-4.8), requiring help injecting compared with not requiring such assistance (adjusted RR 2.1, 95% CI 1.1-3.8), having unsafe sex with a regular partner compared with not having unsafe sex with a regular partner (adjusted RR 2.9, 95% CI 0.9-9.5) and having an HIV-positive sex partner compared with not having an HIV-positive sex partner (adjusted RR 2.7, 95% CI 1.0-7.7) to be independent predictors of time to HIV seroconversion. Among male participants, injecting cocaine once or more per day compared with injecting less than once per day (adjusted RR 3.3, 95% CI 1.9-5.6), self-reporting identification as an Aboriginal compared with not self-reporting identification as an Aboriginal (adjusted RR 2.5, 95% CI 1.4-4.2) and borrowing needles compared with not borrowing needles (adjusted RR 2.0, 95% CI 1.1-3.4) were independent predictors of HIV infection. INTERPRETATION: HIV incidence rates among female injection drug users in Vancouver are about 40% higher than those of male injection drug users. Different risk factors for seroconversion for women as opposed to men suggest that sex-specific prevention initiatives are urgently required.

Adolescent↗
PubMed2002

Vancouver police raid needle exchange run by drug users.

The police claimed that drug trafficking was going on at the needle exchange run by the Vancouver Area Network of Drug Users, but they failed to provide any evidence to that effect. The police later apologized for their remarks and the exchange re-opened.

British Columbia↗
PubMedDate not supplied

Safer injection facility use and syringe sharing in injection drug users.

Safer injection facilities provide medical supervision for illicit drug injections. We aimed to examine factors associated with syringe sharing in a community-recruited cohort of illicit injection drug users in a setting where such a facility had recently opened. Between Dec 1, 2003, and June 1, 2004, of 431 active injection drug users 49 (11.4%, 95% CI 8.5-14.3) reported syringe sharing in the past 6 months. In logistic regression analyses, use of the facility was independently associated with reduced syringe sharing (adjusted odds ratio 0.30, 0.11-0.82, p=0.02) after adjustment for relevant sociodemographic and drug-use characteristics. These findings could help inform discussions about the merits of such facilities.

Blood-Borne Pathogens↗
PubMedDate not supplied

Recent incarceration independently associated with syringe sharing by injection drug users.

OBJECTIVES: Few prospective studies are available on the relationship between incarceration and HIV risk among injection drug users (IDUs). The authors evaluated self-reported rates of syringe sharing and incarceration among a cohort of IDUs. METHODS: This study analyzed syringe lending by HIV-infected IDUs and syringe borrowing by HIV-negative IDUs among participants enrolled in the Vancouver Injection Drug Users Study (VIDUS). Since serial measures for each individual were available, variables potentially associated with each outcome (syringe lending and borrowing) were evaluated using generalized estimating equations for binary outcomes. RESULTS: The study sample consisted of 1,475 IDUs who were enrolled into the VIDUS cohort from May 1996 through May 2002. At baseline, 1,123 (76%) reported a history of incarceration since they first began injecting drugs. Of these individuals, 351 (31%) reported at baseline that they had injected drugs while incarcerated. Among 318 baseline HIV-infected IDUs, having been incarcerated in the six months prior to each interview remained independently associated with syringe lending during the same period (adjusted odds ratio [OR]=1.33; 95% confidence interval [CI] 1.06, 1.69; p=0.015). Similarly, among the 1,157 baseline HIV-negative IDUs, having been incarcerated in the six months prior to each interview remained independently associated with reporting syringe borrowing during the same period (adjusted OR=1.26; 95% CI 1.12, 1.44; p<0.001). CONCLUSIONS: Incarceration was independently associated with risky needle sharing for HIV-infected and HIV-negative IDUs. This evidence of HIV risk behavior should reinforce public health concerns about the high rates of incarceration among IDUs.

Adult↗
PubMedDate not supplied

Requiring help injecting as a risk factor for HIV infection in the Vancouver epidemic: implications for HIV prevention.

BACKGROUND: Requiring help injecting was recently associated with syringe sharing, and later HIV-1 and HCV seroconversion among injection drug users (IDU) in Vancouver. This risk factor remains poorly understood. The present study investigates this risk factor among Vancouver IDUs. METHODS: We evaluated factors associated with requiring help injecting among participants enrolled in the Vancouver Injection Drug User Study (VIDUS) using univariate and logistic regression analyses. VIDUS participants who were followed-up during the period December 2000 to December 2001 were eligible for the present analyses. We also evaluated self-reported reasons for requiring help injecting. RESULTS: Overall, 661 active injection drug users were interviewed during the study period. Among this population, 151 (22.8%) had required help injecting during the last six months, whereas 510 (77.2%) indicated that they had not. Variables that were independently associated with requiring help injecting included borrowing a used syringe (adjusted odds ratio [AOR] = 2.18), frequent cocaine injection (AOR = 1.57), and female gender (AOR = 2.29). Among males, the most common reasons for requiring help injecting were: having no viable veins (77.1%), and anxiousness or being drug sick (42.9%). Among females, the most common reasons reported were: having no viable veins (71.6%), jugular injection or 'jugging' (45.7%), and being anxious or drug sick (27.2%). Almost twice as many females (13.6% vs 7.1%) reported not knowing how to inject as their reason for requiring help injecting. CONCLUSION: Although current public health approaches, such as needle exchange, are unable to address the concerns associated with requiring help injecting, available evidence suggests that safer injecting facilities have the potential to substantially mitigate this risk behaviour.

British Columbia↗
PubMedDate not supplied

Using baseline CD4 cell count and plasma HIV RNA to guide the initiation of highly active antiretroviral therapy.

Conflicting evidence regarding the impact of baseline plasma HIV RNA and CD4 cell count on survival after the initiation of highly active antiretroviral therapy (HAART) in HIV-infected patients has resulted in wide variability in the expert recommendations regarding when to start therapy. Early initiation of HAART may result in avoidable toxicities and premature evolution of resistance, whereas delaying HAART may increase the risk of opportunistic infections and/or preclude a worse virological and clinical response to therapy. While there is widespread consensus that HAART can be delayed to a CD4 cell count of 0.350 x 10(9) cells/L, the range between this threshold and 0.200 x 10(9) cells/L remains controversial. Greater uncertainty surrounds the role of baseline plasma HIV RNA, with some guidelines recommending initiating HAART when this level rises above 55,000 c/mL regardless of baseline CD4 cell count. The following review examines the evidence in support of delaying the initiation of HAART to a CD4 cell count of 0.200 x 10(9) cells/L regardless of plasma HIV RNA levels and outlines supporting data from a Canadian prospective cohort study of antiretroviral naive patients treated with HAART.

Antiretroviral Therapy, Highly Active↗
PubMedDate not supplied

HIV and hepatitis C outbreaks among high-risk youth in Vancouver demands a public health response.

This paper is a call to action. We present Kaplan Meier cumulative HIV and HCV incidence rates among youth aged < or = 24 participating in the Vancouver Injection Drug Users Study (VIDUS), and demonstrate the alarming increase in HIV and HCV incidence rates in addicted youth. The incidence rates among VIDUS youth were 11.1% for HIV and 52.1% for HCV at 36 months after enrollment in the study. The growing epidemic of HIV and HCV among addicted youth calls for policy-makers and program planners to concentrate resources into prevention and treatment of blood-borne infections among British Columbia's vulnerable youth. Without focussing such resources, further HIV and HCV infections and subsequent higher health care costs appear imminent.

Adult↗
PubMedDate not supplied

Rationale to evaluate medically supervised safer smoking facilities for non-injection illicit drug users.

Many cities are experiencing ongoing infectious disease epidemics and substantial community harm as a result of illicit drug use. In an effort to reduce these public order and public health concerns, consideration has been given to the opening in Vancouver of a safer smoking facility (SSF). The present review was conducted to examine if there is a rationale to support the evaluation of a SSF in the Canadian context. Available evidence suggests that conventional drug control strategies are insufficient to address the health and community harms of non-injection drug use, and that the public order benefits of supervised injection facilities may be relevant to SSFs. In addition, there is persuasive evidence to suggest there is potential for blood-borne disease transmission through the sharing of smoking paraphernalia, and the potential for SSFs to address this concern is a pressing public health question. Also relevant to this topic are interventions to prevent transition into injection drug use, and SSFs may also be evaluated as a potential strategy to address this concern.

Amphetamine-Related Disorders↗