Immunological and virological response to initial antiretroviral therapy among older people living with HIV in the Canadian Observational Cohort (CANOC).

OBJECTIVES: The aim of this study was to assess the adequacy of immunological recovery and virological suppression in response to antiretroviral therapy (ART) in the growing population of older people living with HIV (PLWH), as treatment regimens become more effective and tolerable. METHODS: An interprovincial Canadian cohort of treatment-naïve PLWH who initiated ART after 1 January 2000 was used and age assessed in decades. Longitudinal absolute CD4 count response to treatment was modelled using generalized estimating equations. Cumulative incidence functions and proportional hazards models with a competing risk of death were used to estimate time to: (1) CD4 ≥ 200 cells/µL, (2) CD4 ≥ 500 cells/µL, (3) virological suppression (≤ 50 copies/mL), and (4) virological failure (> 200 copies/mL). RESULTS: In all, 12 489 individuals starting ART between 2000 and 2016 with one or more post-treatment CD4 count or viral load were included in the analysis. Age > 60 years was associated with lower absolute CD4 recovery (adjusted ß = -31 cells/µL) compared with age ≤ 30 years when pre-treatment CD4 count and other covariates were accounted for. Older age groups were less likely to achieve a CD4 ≥ 500 cells/µL, with the greatest effect in the > 60 group [adjusted hazard ratio (aHR) = 0.69, 95% confidence interval (CI): 0.57-0.84 vs. age ≤ 30). Older age groups were more likely to achieve viral suppression (age > 60, aHR = 1.20, 95% CI: 1.05-1.37) and less likely to have virological failure (age > 60, aHR = 0.46, 95% CI: 0.3-0.71) compared with those aged ≤ 30 years. CONCLUSIONS: Older adults have robust virological responses to ART; however, individuals over the age 60 are more likely to experience blunted CD4 recovery.

Quality of initial HIV care in Canada: extension of a composite programmatic assessment tool for HIV therapy.

OBJECTIVES: To document the quality of initial HIV care in Canada using the Programmatic Compliance Score (PCS), to explore the association of the PCS with mortality, and to identify factors associated with higher quality of care. METHODS: We analysed data from the Canadian Observational Cohort Collaboration (CANOC), a multisite Canadian cohort of HIV-positive adults initiating combination antiretroviral therapy (ART) from 2000 to 2011. PCS indicators of noncompliance with HIV treatment guidelines include: fewer than three CD4 count tests in the first year of ART; fewer than three viral load tests in the first year of ART; no drug resistance testing before initiation; baseline CD4 count < 200 cells/mm3 ; starting a nonrecommended ART regimen; and not achieving viral suppression within 6 months of initiation. Indicators are summed for a score from 0 to 6; higher scores indicate poorer care. Cox regression was used to assess the association between PCS and mortality and ordinal logistic regression was used to explore factors associated with higher quality of care. RESULTS: Of the 7460 participants (18% female), the median score was 1.0 (Q1-Q3 1.0-2.0); 21% scored 0 and 8% scored ≥ 4. In multivariable analysis, compared with a score of 0, poorer PCS was associated with mortality for scores > 1 [score = 2: adjusted hazard ratio (AHR) 1.64; 95% confidence interval (CI) 1.13-2.36; score = 3: AHR 2.02; 95% CI 1.38-2.97; score ≥ 4: AHR 2.14; 95% CI 1.43-3.21], after adjustments for age, sex, province, ART start year, hepatitis C virus (HCV) coinfection, and baseline viral load. Women, individuals with HCV coinfection, younger people, and individuals starting ART earlier (2000-2003) had poorer scores. CONCLUSIONS: Our findings further validate the PCS as a predictor of all-cause mortality. Disparities identified suggest that further efforts are needed to ensure that care is equitably accessible.

A tale of two countries: all-cause mortality among people living with HIV and receiving combination antiretroviral therapy in the UK and Canada.

OBJECTIVES: We sought to compare all-cause mortality of people living with HIV and accessing care in Canada and the UK. METHODS: Individuals from the Canadian Observational Cohort (CANOC) collaboration and UK Collaborative HIV Cohort (UK CHIC) study who were aged ≥ 18 years, had initiated antiretroviral therapy (ART) for the first time between 2000 and 2012 and who had acquired HIV through sexual transmission were included in the analysis. Cox regression was used to investigate the difference in mortality risk between the two cohort collaborations, accounting for loss to follow-up as a competing risk. RESULTS: A total of 19 960 participants were included in the analysis (CANOC, 4137; UK CHIC, 15 823). CANOC participants were more likely to be older [median age 39 years (interquartile range (IQR): 33, 46 years) vs. 36 years (IQR: 31, 43 years) for UK CHIC participants], to be male (86 vs. 73%, respectively), and to report men who have sex with men (MSM) sexual transmission risk (72 vs. 56%, respectively) (all P < 0.001). Overall, 762 deaths occurred during 98 798 person-years (PY) of follow-up, giving a crude mortality rate of 7.7 per 1000 PY [95% confidence interval (CI): 7.1, 8.3 per 1000 PY]. The crude mortality rates were 8.6 (95% CI: 7.4, 10.0) and 7.5 (95% CI: 6.9, 8.1) per 1000 PY among CANOC and UK CHIC study participants, respectively. No statistically significant difference in mortality risk was observed between the cohort collaborations in Cox regression accounting for loss to follow-up as a competing risk (adjusted hazard ratio 0.86; 95% CI: 0.72-1.03). CONCLUSIONS: Despite differences in national HIV care provision and treatment guidelines, mortality risk did not differ between CANOC and UK CHIC study participants who acquired HIV through sexual transmission.

Does age matter? Sexual event-level analysis of age-disparate sexual partners among gay, bisexual and other men who have sex with men (GBM) in Vancouver, Canada.

BACKGROUND: To determine factors associated with age-disparate sexual partners among Vancouver gay, bisexual and other men who have sex with men (GBM). METHODS: Sexually active GBM aged ≥16 years were recruited from February 2012 to February 2014. Participants self-completed a questionnaire on demographics, attitudes and sexual behaviour and substance use at last sexual event with five most recent partners. Two generalised linear mixed models identified factors associated with: (1) 'same-age' (referent), 'younger' or 'much-younger' and (2) 'same-age' (referent), 'older' or 'much-older' partners. Statistical interactions between age and HIV status were tested. RESULTS: Participants (n=719) were predominantly gay (85.1%), White (75.0%), HIV-negative/unknown status (72.9%) with median age of 33 years (Q1,Q3: 26,47). A minority of sexual events were reported with much-older/much-younger partners (13.7%). In the multivariable models, GBM reporting older partners were more likely to be Asian or Latino, have greater Escape Motivation scores, report their partner used erectile dysfunction drugs (EDDs) and have received something for sex; compared with condom-protected insertive anal sex, participants with older partners were more likely to report condomless insertive anal sex with a serodiscordant or unknown status partner or no insertive anal sex. GBM reporting older partners were less likely to be bisexual-identified, have given something for sex and report event-level alcohol and EDD use. GBM reporting younger partners were more likely to have annual incomes >$30 000 and have met their partner online. As per significant statistical interactions, age-disparate relations were more common for younger HIV-positive and older HIV-negative GBM. CONCLUSIONS: Differences among age-disparate partners highlight important targets for health promotion and future research.

Reductions in all-cause and cause-specific mortality among HIV-infected individuals receiving antiretroviral therapy in British Columbia, Canada: 2001-2012.

OBJECTIVES: Since 2006, the British Columbia HIV/AIDS Drug Treatment Program (DTP) has expanded enrolment and dramatically increased its number of participants. We examined the effect this expansion has had on the underlying cause of death in HIV-infected individuals. METHODS: We analysed data from participants aged 18 years and older in the DTP to measure 2-year mortality rates and causes of death from 2001 to 2012. We conducted tests of trend for all-cause and cause-specific mortality, and compared demographics and characteristics of individuals. Cox proportional hazard models were used to determine the risk of death. RESULTS: A total of 8185 participants received antiretroviral therapy (ART) during the study period. Mortality declined from 3.88 per 100 person-years (PY) in 2001-2002 to 2.15 per 100 PY in 2011-2012 (P = 0.02). There were significant decreases in HIV-related deaths (2.34 to 0.56 per 100 PY; P = 0.02) and deaths attributable to chronic liver disease (0.20 to 0.09 per 100 PY; P = 0.01), cardiovascular disease (0.24 to 0.05 per 100 PY; P = 0.03) and suicides (0.47 to 0 per 100 PY; P = 0.003). Multivariate models, adjusted for age, gender, history of injecting drug use, AIDS diagnoses and baseline CD4 cell counts, demonstrated that initiation of ART in all time periods after 2001-2002 was independently associated with reduced mortality (P < 0.001). CONCLUSIONS: We observed declines in HIV-related mortality and certain non-HIV-related causes of death among participants in the BC DTP from 2001 to 2012. These findings suggest that there may be broader benefits to the increasingly liberal HIV treatment guidelines, including reductions in death caused by cardiovascular disease and chronic liver disease.

Cancer incidence among HIV-positive women in British Columbia, Canada: Heightened risk of virus-related malignancies.

OBJECTIVES: We used population-based data to identify incident cancer cases and correlates of cancer among women living with HIV/AIDS in British Columbia (BC), Canada between 1994 and 2008. METHODS: Data were obtained from a retrospective population-based cohort created from linkage of two province-wide databases: (1) the database of the BC Cancer Agency, a province-wide population-based cancer registry, and (2) a database managed by the BC Centre for Excellence in HIV/AIDS, which contains data on all persons treated with antiretroviral therapy in BC. This analysis included women (≥ 19 years old) living with HIV in BC, Canada. Incident cancer diagnoses that occurred after highly active antiretroviral therapy (HAART) initiation were included. We obtained a general population comparison of cancer incidence among women from the BC Cancer Agency. Bivariate analysis (Pearson χ(2) , Fisher's exact or Wilcoxon rank-sum test) compared women with and without incident cancer across relevant clinical and sociodemographic variables. Standardized incidence ratios (SIRs) were calculated for selected cancers compared with the general population sample. RESULTS: We identified 2211 women with 12 529 person-years (PY) of follow-up who were at risk of developing cancer after HAART initiation. A total of 77 incident cancers (615/100 000 PY) were identified between 1994 and 2008. HIV-positive women with cancer, in comparison to the general population sample, were more likely to be diagnosed with invasive cervical cancer, Hodgkin's lymphoma, non-Hodgkin's lymphoma and Kaposi's sarcoma and less likely to be diagnosed with cancers of the digestive system. CONCLUSIONS: This study observed elevated rates of cancer among HIV-positive women compared to a general population sample. HIV-positive women may have an increased risk for cancers of viral-related pathogenesis.

Awareness and use of nonoccupational post-exposure prophylaxis among men who have sex with men in Vancouver, Canada.

OBJECTIVES: Nonoccupational post-exposure prophylaxis (nPEP) is a strategy to reduce the risk of HIV infection in those with high-risk exposure. This study characterized nPEP awareness among gay, bisexual and other men who have sex with men (MSM) in Metro Vancouver, British Columbia, Canada after a pilot nPEP programme established in 2012. METHODS: Momentum Health Study participants were MSM aged ≥16 years recruited via respondent-driven sampling (RDS) who completed a computer-assisted self-interview. Stratifying patients by HIV status, we used multivariable logistic regression with backward selection to identify factors associated with nPEP awareness. All analyses were RDS-adjusted. RESULTS: A total of 51.9% (112 of 173) of HIV-positive and 48.5% (272 of 500) of HIV-negative participants had heard of nPEP. Only 3% (five of 106) of HIV-negative participants who reported recent high-risk sex used nPEP. Generally, nPEP awareness was higher for participants who engaged in sexual activities with increased HIV transmission potential. Factors associated with greater awareness among HIV-negative participants included recent alcohol use, higher communal sexual altruism, previous sexually transmitted infection diagnosis, and greater perceived condom use self-efficacy. Other factors associated with greater awareness among HIV-negative participants included white race/ethnicity, gay sexual identity, more formal education, lower personal sexual altruism, and Vancouver residence. Greater nPEP awareness among HIV-positive participants was associated with greater perceived agency to ask sexual partners' HIV status and more frequently reporting doing so, a higher number of lifetime receptive sex partners, and greater access to condoms. CONCLUSIONS: Following implementation of an nPEP pilot programme, nPEP awareness among HIV-negative MSM was 51% and use was 3%. These data support the need to expand access to and actively promote nPEP services.

An integrated approach to care attracts people living with HIV who use illicit drugs in an urban centre with a concentrated HIV epidemic.

BACKGROUND: People living with HIV (PLHIV) who are also marginalized by social and structural inequities often face barriers to accessing and adhering to HIV treatment and care. The Dr. Peter Centre (DPC) is a non-profit integrated care facility with a supervised injection room that serves PLHIV experiencing multiple barriers to social and health services in Vancouver, Canada. This study examines whether the DPC is successful in drawing in PLHIV with complex health issues, including addiction. METHODS: Using data collected by the Longitudinal Investigations into Supportive and Ancillary health services (LISA) study from July 2007 to January 2010, linked with clinical variables available through the British Columbia Centre for Excellence in HIV/AIDS Drug Treatment Program, we identified DPC and non-DPC clients with a history of injection drug use. Bivariable and multivariable logistic regression analyses compared socio-demographic and clinical characteristics of DPC clients (n = 76) and non-DPC clients (n = 482) with a history of injection drug use. RESULTS: Of the 917 LISA participants included within this analysis, 100 (10.9%) reported being a DPC client, of which 76 reported a history of injection drug use. Adjusted results found that compared to non-DPC clients with a history of injection drug use, DPC-clients were more likely to be male (AOR: 4.18, 95% CI = 2.09-8.37); use supportive services daily vs. less than daily (AOR: 3.16, 95% CI = 1.79-5.61); to have been diagnosed with a mental health disorder (AOR: 2.11; 95% CI: 1.12-3.99); to have a history of interpersonal violence (AOR: 2.76; 95% CI: 1.23-6.19); and to have ever experienced ART interruption longer than 1 year (AOR: 2.39; 95% CI: 1.38-4.15). CONCLUSIONS: Our analyses suggest that the DPC operating care model engages PLHIV with complex care needs, highlighting that integrated care facilities are needed to support the multiple intersecting vulnerabilities faced by PLHIV with a history of injection drug use living within urban centres in North America and beyond.

Declines in highly active antiretroviral therapy initiation at CD4 cell counts ≤ 200 cells/µL and the contribution of diagnosis of HIV at CD4 cell counts ≤ 200 cells/µL in British Columbia, Canada.

OBJECTIVES: The aim of the study was to examine trends in initiating highly active antiretroviral therapy (HAART) with a CD4 count ≤ 200 cells/µL and the contribution of having a CD4 count ≤ 200 cells/µL at the time of diagnosis to these trends, in British Columbia (BC), Canada. METHODS: We included in the analysis treatment-naïve BC residents aged ≥ 19 years who initiated HAART from 2003 to 2012. Participants were classified as follows: Group 1: diagnosed and initiated HAART with a CD4 count > 200 cells/µL; Group 2: diagnosed with a CD4 count > 200 cells/µL and initiated HAART with a CD4 count ≤ 200 cells/µL; and Group 3: diagnosed and initiated HAART with a CD4 count ≤ 200 cells/µL. We measured trends in initiating HAART with a CD4 count ≤ 200 cells/µL and used logistic regression models to measure factors associated with initiating HAART with a CD4 count ≤ 200 cells/µL, stratified by having a CD4 count ≤ 200 cells/µL or > 200 cells/µL at the time of diagnosis. RESULTS: Between 2003 and 2012, 3506 BC residents initiated HAART. Of these, 44% (1558 of 3506) initiated HAART with a CD4 count ≤ 200 cells/µL. This proportion declined from 69% (198 of 287) in 2003 to 21% (81 of 330) in 2012 (P < 0.001). The proportion of those in Group 3 increased from 49% (97 of 198) in 2003 to 69% (56 of 81) in 2012 (P < 0.001). Overall, 56% (1948), 22% (776) and 22% (782) made up Groups 1, 2, and 3, respectively. In adjusted analyses, seeing a specialist was significantly associated with being in Group 3. Using injection drugs and seeing a specialist were associated with being in Group 2. CONCLUSIONS: In recent years, among individuals who ever initiated HAART in BC, being diagnosed with low CD4 cell counts has become a greater contributor to initiating HAART with low CD4 cell counts.

Predictors of unstructured antiretroviral treatment interruption and resumption among HIV-positive individuals in Canada.

OBJECTIVES: Sustained optimal use of combination antiretroviral therapy (cART) has been shown to decrease morbidity, mortality and HIV transmission. However, incomplete adherence and treatment interruption (TI) remain challenges to the full realization of the promise of cART. We estimated trends and predictors of treatment interruption and resumption among individuals in the Canadian Observational Cohort (CANOC) collaboration. METHODS: cART-naïve individuals ≥ 18 years of age who initiated cART between 2000 and 2011 were included in the study. We defined TIs as ≥ 90 consecutive days off cART. We used descriptive analyses to study TI trends over time and Cox regression to identify factors predicting time to first TI and time to treatment resumption after a first TI. RESULTS: A total of 7633 participants were eligible for inclusion in the study, of whom 1860 (24.5%) experienced a TI. The prevalence of TI in the first calendar year of cART decreased by half over the study period. Our analyses highlighted a higher risk of TI among women [adjusted hazard ratio (aHR) 1.59; 95% confidence interval (CI) 1.33-1.92], younger individuals (aHR 1.27; 95% CI 1.15-1.37 per decade increase), earlier treatment initiators (CD4 count ≥ 350 vs. <200 cells/µL: aHR 1.46; 95% CI 1.17-1.81), Aboriginal participants (aHR 1.67; 95% CI 1.27-2.20), injecting drug users (aHR 1.43; 95% CI 1.09-1.89) and users of zidovudine vs. tenofovir in the initial cART regimen (aHR 2.47; 95% CI 1.92-3.20). Conversely, factors predicting treatment resumption were male sex, older age, and a CD4 cell count <200 cells/µL at cART initiation. CONCLUSIONS: Despite significant improvements in cART since its advent, our results demonstrate that TIs remain relatively prevalent. Strategies to support continuous HIV treatment are needed to maximize the benefits of cART.

Characteristics and determinants of T-cell phenotype normalization in HIV-1-infected individuals receiving long-term antiretroviral therapy.

OBJECTIVES: Although combination antiretroviral therapy (cART) can restore CD4 T-cell numbers in HIV infection, alterations in T-cell regulation and homeostasis persist. We assessed the incidence and predictors of reversing these alterations with cART. METHODS: ART-naïve adults (n = 4459) followed within the Canadian Observational Cohort and exhibiting an abnormal T-cell phenotype (TCP) prior to cART initiation were studied. Abnormal TCP was defined as having (1) a low CD4 T-cell count (< 532 cells/µL), (2) lost T-cell homeostasis (CD3 < 65% or > 85%) or (3) CD4:CD8 ratio dysregulation (ratio < 1.2). To thoroughly evaluate the TCP, CD4 and CD8 T-cell percentages and absolute counts were also analysed for a median duration of 3.14 years [interquartile range (IQR) 1.48-5.47 years]. Predictors of TCP normalization were assessed using adjusted Cox proportional hazards models. RESULTS: At baseline, 96% of pateints had CD4 depletion, 32% had lost homeostasis and 99% exhibited ratio dysregulation. With treatment, a third of patients had normalized CD4 T-cell counts, but only 85 individuals (2%) had normalized their TCP. In a multivariable model adjusted for age, measurement frequency and baseline regimen, higher baseline CD4 T-cell counts and time-dependent viral suppression independently predicted TCP normalization [hazard ratio (HR) for baseline CD4 T-cell count = 1.42 (1.31-1.54) per 100 cells/µL increase; P ≤ 0.0001; HR for time-dependent suppressed viral load = 3.69 (1.58-8.61); P-value ≤ 0.01]. CONCLUSIONS: Despite effective cART, complete TCP recovery occurred in very few individuals and was associated with baseline CD4 T-cell count and viral load suppression. HIV-induced alterations of the TCP are incompletely reversed by long-term ART.

The effect of injecting drug use history on disease progression and death among HIV-positive individuals initiating combination antiretroviral therapy: collaborative cohort analysis.

BACKGROUND: We examined whether determinants of disease progression and causes of death differ between injecting drug users (IDUs) and non-IDUs who initiate combination antiretroviral therapy (cART). METHODS: The ART Cohort Collaboration combines data from participating cohort studies on cART-naïve adults from cART initiation. We used Cox models to estimate hazard ratios for death and AIDS among IDUs and non-IDUs. The cumulative incidence of specific causes of death was calculated and compared using methods that allow for competing risks. RESULTS: Data on 6269 IDUs and 37 774 non-IDUs were analysed. Compared with non-IDUs, a lower proportion of IDUs initiated cART with a CD4 cell count <200 cells/µL or had a prior diagnosis of AIDS. Mortality rates were higher in IDUs than in non-IDUs (2.08 vs. 1.04 per 100 person-years, respectively; P<0.001). Lower baseline CD4 cell count, higher baseline HIV viral load, clinical AIDS at baseline, and later year of cART initiation were associated with disease progression in both groups. However, the inverse association of baseline CD4 cell count with AIDS and death appeared stronger in non-IDUs than in IDUs. The risk of death from each specific cause was higher in IDUs than non-IDUs, with particularly marked increases in risk for liver-related deaths, and those from violence and non-AIDS infection. CONCLUSION: While liver-related deaths and deaths from direct effects of substance abuse appear to explain much of the excess mortality in IDUs, they are at increased risk for many other causes of death, which may relate to suboptimal management of HIV disease in these individuals.

Relationship of chronic hepatitis C infection to rates of AIDS-defining illnesses in a Canadian cohort of HIV seropositive individuals receiving highly active antiretroviral therapy.

BACKGROUND: The influence of chronic hepatitis C virus (HCV) infection on the risk, timing, and type of AIDS-defining illnesses (ADIs) is not well described. To this end, rates of ADIs were evaluated in a Canadian cohort of HIV seropositive individuals receiving highly active antiretroviral therapy (HAART). METHODS: ADIs were classified into 6 Centers for Disease Control and Prevention (CDC)-defined etiological subgroups: non-Hodgkin lymphoma, viral infection, bacterial infection, HIV-related disease, protozoal infection, and mycotic infection. Generalized estimating equation (GEE) Poisson regression models were used to estimate the effect of HCV on rates of ADIs after adjusting for covariates. RESULTS: Among 2,706 HAART recipients, 768 (28%) were HCV coinfected. Rates of all ADIs combined and of bacterial infection, HIV-related disease, and mycotic infection were increased in HCV-coinfected persons and among those with CD4 counts <200 cells/mm3 HCV was associated with an increased risk of ADIs (rate ratio [RR], 1.38; 95% CI, 1.01-1.88) and a 2-fold increased risk of mycotic infections (RR, 2.21; 95% CI, 1.35-3.62) in univariate analyses and after adjusting for age, baseline viral load, baseline CD4 count, and region of Canada. However, after further adjustment for HAART interruptions, HCV was no longer associated with an increased rate of ADIs overall (RR, 1.13; 95% CI, 0.80-1.59), but remained associated with an increased rate of mycotic infections (RR, 1.97, 95% CI, 1.08-3.61). CONCLUSION: Although HCV coin-fected individuals are at increased risk of developing ADIs overall, our analysis suggests that behavioral variables associated with HCV (including rates of retention on HAART), and not biological interactions with HCV itself, are primarily responsible.

Factors associated with virological suppression among HIV-positive individuals on highly active antiretroviral therapy in a multi-site Canadian cohort.

OBJECTIVE: The aim of the study was to evaluate time to virological suppression in a cohort of individuals who started highly active antiretroviral therapy (HAART), and to explore the factors associated with suppression. METHODS: Eligible participants were HIV-positive individuals from a multi-site Canadian cohort of antiretroviral-naïve patients initiating HAART on or after 1 January 2000. Viral load and CD4 measurements within 6 months prior to HAART initiation were assessed. Univariate and multivariate analyses were conducted using piecewise survival exponential models where time scale was divided into intervals (<10 months; ≥10 months). Virological suppression was defined as the time to the first of at least two consecutive viral load measurements <50 HIV-1 RNA copies/mL. RESULTS: A total of 3555 individuals were included in the study, of median age 40 years [interquartile range (IQR) 34-47 years]. Eighty per cent were male, 18% had a history of injecting drug use (IDU), and 13% presented with an AIDS-defining illness at baseline. The median time to suppression was 4.55 months (IQR 2.99-7.89 months). In multivariate analyses, older age, male sex, treatment in Ontario rather than British Columbia, non-IDU history, and having an AIDS diagnosis at baseline predicted increased likelihood of suppression. Patients with low baseline viral load were more likely to have suppression [4-5 log(10) copies/mL, hazard ratio (HR) 1.27, 95% confidence interval (CI) 1.18-1.38; <4 log(10) copies/mL, HR 1.49, 95% CI 1.32-1.68] than patients with baseline viral load ≥5 log(10) copies/mL; however, this effect ceased after 18 months of follow-up. Suppression was more likely with nonnucleoside reverse transcriptase inhibitors and ritonavir-boosted HAART. CONCLUSION: Identification of patients at risk for diminished likelihood of virological suppression will allow focusing of efforts and the utilization of resources to maximize the benefits of HAART.

High prevalence of food insecurity among HIV-infected individuals receiving HAART in a resource-rich setting.

This study aimed to assess the prevalence and correlates of food insecurity in a cohort of HIV-infected individuals on highly active antiretroviral therapy (HAART) in British Columbia (BC), Canada. Adults receiving HAART voluntarily enrolled into the Longitudinal Investigations into Supportive and Ancillary Health Services (LISA) cohort. Individual food insecurity was measured using a modified version of the Radimer/Cornell Questionnaire. We performed bivariate analyses to determine differences between explanatory variables for individuals who were food secure and food insecure. We performed logistic regression to determine independent predictors of food insecurity. Of the 457 individuals enrolled in the LISA cohort, 324 (71.0%) were found to be food insecure. Multivariate analysis indicated that individuals who had an annual incomes less than $15,000 (odds ratio [OR] 3.15, 95% confidence interval [CI] 1.83, 5.44), used illicit drugs (OR 1.85, 95% CI 1.03, 3.33), smoked tobacco (OR 2.30, 95% CI 1.30, 4.07), had depressive symptoms (OR 2.34, 95% CI 1.38, 3.96), and were younger (OR 0.95, 95% CI, 0.92, 0.98) were more likely to be food insecure. Our results demonstrated a high (71%) prevalence of food insecurity among HIV-infected individuals receiving HAART in this resource-rich setting, and that food insecurity is associated with a compendium of environmental and behavioral factors. More research is needed to understand the biological and social pathways linking food insecurity to these variables in order to identify program strategies that can effectively improve food security among HIV-infected populations.

Suboptimal use of HIV drug resistance testing in a universal health-care setting.

HIV drug resistance testing is recommended as routine part of clinical practice in HIV/AIDS treatment and care. Our objective is to assess the determinants of accessing HIV drug resistance testing and examine the factors associated with resistance testing prior to or after starting highly active antiretroviral therapy (HAART) in a setting where access to HIV care is free and universal. The Longitudinal Investigation into Supportive and Ancillary health services (LISA) study is an open prospective cohort of HIV-positive persons on HAART in British Columbia (BC), Canada. Non-clinical data were collected through an interviewer-administered survey and clinical data were obtained through the BC Centre for Excellence in HIV/AIDS Drug Treatment Program. Independent associations between key explanatory variables and resistance testing were analyzed using logistic regression. We restricted our post-HAART analyses to those patients who met the criteria for resistance testing after HAART initiation. Of 359 LISA participants who started HAART after 2000 and at a time when resistance testing was available free of charge, almost half did not receive a baseline resistance test. Post-HAART initiation, 165 of 359 study subjects met the criteria for resistance testing based on current therapeutic guidelines due to virological failure. About 37.6% of them remain untested for resistance. Multivariable analyses show that baseline testing was less likely performed for persons of Aboriginal ethnicity and more likely performed for patients initiating HAART in 2004 or after. Additionally, persons initiating HAART in 2004 or after were less likely to have received a resistance test after virologic failure. Our results show that despite existing clinical guidelines, resistance testing is underused, even in an environment where the service is available free of charge. Further, resistance testing is particularly underutilized among vulnerable populations. Urgent efforts are needed to ensure the optimal use of resistance testing at baseline and at the time of virologic failure as recommended by current guidelines.

Non-medically supervised treatment interruptions among participants in a universally accessible antiretroviral therapy programme.

BACKGROUND: We examined clinical outcomes, patient characteristics and trends over time of non-medically supervised treatment interruptions (TIs) from a free-of-charge antiretroviral therapy (ART) programme in British Columbia (BC), Canada. METHODS: Data from ART-naïve individuals > or =18 years old who initiated triple combination highly active antiretroviral therapy (HAART) between January 2000 and June 2006 were analysed. Participants having > or =3 month gap in HAART coverage were defined as having a TI. Cox proportional hazards modelling was used to examine factors associated with TIs and to examine factors associated with resumption of treatment. RESULTS: A total of 1707 participants were study eligible and 643 (37.7%) experienced TIs. TIs within 1 year of ART initiation decreased from 29% of individuals in 2000 to 19% in 2006 (P<0.001). TIs were independently associated with a history of injection drug use (IDU) (P=0.02), higher baseline CD4 cell counts (P<0.001), hepatitis C co-infection (P<0.001) and the use of nelfinavir (NFV) (P=0.04) or zidovudine (ZDV)/lamivudine (3TC) (P=0.009) in the primary HAART regimen. Male gender (P<0.001), older age (P<0.001), AIDS at baseline (P=0.008) and having a physician who had prescribed HAART to fewer patients (P=0.03) were protective against TIs. Four hundred and eighty-eight (71.9%) participants eventually restarted ART with male patients and those who developed an AIDS-defining illness prior to their TI more likely to restart therapy. Higher CD4 cell counts at the time of TI and unknown hepatitis C status were associated with a reduced likelihood of restarting ART. CONCLUSION: Treatment interruptions were associated with younger, less ill, female and IDU participants. Most participants with interruptions eventually restarted therapy. Interruptions occurred less frequently in recent years.

An assessment of global Internet-based HIV/AIDS media coverage: implications for United Nations Programme on HIV/AIDS' Global Media HIV/AIDS initiative.

No studies to date have assessed the quantity of HIV/AIDS-related media on the Internet. We assessed the quantity of language-specific HIV/AIDS Internet-based news coverage, and the correlation between country-specific HIV/AIDS news coverage and HIV/AIDS prevalence. Internet-based HIV/AIDS news articles were queried from Google News Archives for 168 countries, for the year 2007, in the nine most commonly spoken languages worldwide. English, French and Spanish sources had the greatest number of HIV/AIDS-related articles, representing 134,000 (0.70%), 11,200 (0.65%) and 24,300 (0.49%) of all news articles, respectively. A strong association between country-specific HIV/AIDS news coverage and HIV/AIDS prevalence was found, Spearman's rank correlation: 0.6 (P < 0.001). Among countries with elevated HIV/AIDS prevalence (> or =10%), the volume of HIV/AIDS-specific media was highest in Swaziland (15.9%) and Malawi (13.2%), and lowest in South Africa (4.8%) and Namibia (4.9%). Increased media attention should be placed on countries with high HIV/AIDS prevalence and limited HIV/AIDS-specific news coverage.

Mortality is influenced by locality in a major HIV/AIDS epidemic.

OBJECTIVES: The aim of the study was to compare the risks of death among HIV-infected patients on highly active antiretroviral therapy (HAART) in two proximate, yet distinct neighbourhoods: a neighbourhood with a high concentration of gay men, and a neighbourhood with a high concentration of injecting drug users. METHODS: We compared the clinical and socioeconomic characteristics of HIV-infected patients from the two neighbourhoods entering the British Columbia Centre for Excellence in HIV/AIDS Drug Treatment Program from 1 September 1997 to 30 November 2005, using contingency table statistics. Cox survival models and Kaplan-Meier methods were used to estimate the cumulative mortality rates. RESULTS: We found significant differences between patients from the two neighbourhoods for all socioeconomic variables. Patients in the neighbourhood with a high concentration of injecting drug users were more likely to be female, have a history of injecting drug use, have a less HIV-experienced physician and be less adherent. Patients in the neighbourhood with a high concentration of gay men were more likely to have AIDS. Mortality was significantly higher for patients in the neighbourhood with a high concentration of injecting drug users [hazard ratio (HR) 3.01; 95% confidence interval (CI) 1.73, 5.24]. CONCLUSIONS: A threefold increase was observed in the risk of death among HIV-infected individuals on HAART in the neighbourhood with a high concentration of injecting drug users relative to the neighbourhood with a high concentration of gay men. The implications of this study should be assessed in similar HIV/AIDS epicentres.

Health care services utilization stratified by virological and immunological markers of HIV: evidence from a universal health care setting.

OBJECTIVE: The aim of the study was to determine rates of utilization of in-patient, out-patient and laboratory services stratified by virological and immunological markers of HIV disease among patients on antiretroviral treatment in British Columbia, Canada. METHODS: We estimated resource utilization for in-patient visits, out-patient visits, and laboratory tests among patients initiating antiretroviral treatment between 1 April 1994 and 31 December 2000, with follow-up to 31 March 2001. Resource use was stratified by CD4 cell count and plasma HIV viral load (pVL) at the time of utilization and rates per 100 patient-years were calculated for each health care resource. RESULTS: A total of 2718 patients were included in our analyses. The overall rates of in-patient visits, out-patient visits, and laboratory tests were 902, 3001 and 840 per 100 patient-years, respectively. Utilization was higher for patients with low CD4 cell counts and high pVLs when compared with patients with high CD4 cell counts and low pVLs. CONCLUSIONS: Patients with low CD4 cell counts and high pVLs had the highest use of health care services. Regular follow-up with health care providers in an out-patient setting, allowing for proper monitoring and maintenance of HIV care, is important in minimizing unnecessary and potentially costly in-patient care.