The EuroSIDA study: 25 years of scientific achievements.

The EuroSIDA study was initiated in 1994 and follows adult people living with HIV (PLHIV) in 100 collaborating clinics across 35 countries covering all European regions, Israel and Argentina. The study aims to study the long-term virological, immunological and clinical outcomes of PLHIV and to monitor temporal changes and regional differences in outcomes across Europe. Annually collected data include basic demographic characteristics, information on AIDS- and non-AIDS-related clinical events, and details about antiretroviral therapy (ART), hepatitis C treatment and other medications, in addition to a range of laboratory values. The summer 2016 data set held data from a total of 23 071 individuals contributing 174 481 person-years of follow-up, while EuroSIDA's unique plasma repository held over 160 000 samples. Over the past 25 years, close to 300 articles have been published in peer-reviewed journals (h-index 52), covering a range of scientific focus areas, including monitoring of clinical and virological outcomes, ART uptake, efficacy and adverse events, the influence of hepatitis virus coinfection, variation in the quality of HIV care and management across settings and regions, and biomarker research. Recognizing that there remain unresolved issues in the clinical care and management of PLHIV in Europe, EuroSIDA was one of the cohorts to found The International Cohort Consortium of Infectious Disease (RESPOND) cohort consortium on infectious diseases in 2017. In celebration of the EuroSIDA study's 25th anniversary, this article aims to summarize key scientific findings and outline current and future scientific focus areas.

CSF inflammatory markers and neurocognitive function after addition of maraviroc to monotherapy darunavir/ritonavir in stable HIV patients: the CINAMMON study.

CINAMMON is a phase IV, open-label, single-arm, pilot study assessing maraviroc (MVC) in the central nervous system (CNS) when added to darunavir/ritonavir monotherapy (DRV/r) in virologically suppressed HIV-infected subjects. CCR5 tropic participants on DRV/r were recruited. Participants remained on DRV/r for 12 week (w) (control phase). MVC 150 mg qd was added w12-w36 (intervention phase). Lumbar puncture (LP) and neurocognitive function (Cogstate) examinations scheduled at baseline, w12 and w36; MRI before w12, again at w36. Primary endpoint was CSF inflammatory marker changes during intervention phase. Secondary endpoints included changes in NC function and MRI parameters. CSF/plasma DRV/r concentrations measured at w12 and w36, MVC at w36. Nineteen patients recruited, 15 completed (17M, 2F). Dropouts: headache (2), knee problem (could not attend, 1), personal reasons (1). Mean age (range) 45.4 years (27.2-65.1), 13/19 white, 10/19 MSM. No changes in selected CSF markers were seen w12-w36. Overall NC function did not improve w12-w36: total age adjusted z score improved by 0.27 (weighted paired t test; p = 0.11); for executive function only, age adjusted z score improved by 0.54 (p = 0.03). MRI brain parameters unchanged. DRV plasma:CSF concentration ratio unchanged between w12 (132) and w36 (112; p = 0.577, Wilcoxon signed-rank). MVC plasma:CSF concentration ratio was 35 at w36. No changes in neuroinflammatory markers seen. In this small study, addition of 24w MVC 150 mg qd to stable DRV/r monotherapy showed possible improvement in executive function with no global NC effect. Learning effect cannot be excluded. This effect should be further evaluated.

Correction to: CSF inflammatory markers and neurocognitive function after addition of maraviroc to monotherapy darunavir/ritonavir in stable HIV patients: the CINAMMON study.

Due to a production error the bottom portion of Figure 1 was omitted. The corrected figure is given below.

Clinical and demographic factors associated with low viral load in early untreated HIV infection in the INSIGHT Strategic Timing of AntiRetroviral Treatment (START) trial.

OBJECTIVES: A small subset of HIV-positive adults have low HIV RNA in the absence of therapy, sometimes for years. Clinical factors associated with low HIV RNA in early infection have not been well defined. METHODS: We assessed factors associated with low plasma HIV RNA level at study entry in the Strategic Timing of AntiRetroviral Treatment (START) trial. All START participants had a baseline HIV RNA assessment within 60 days prior to randomization. The key covariables considered for this analysis were race, and hepatitis B virus (HBV) and hepatitis C virus (HCV) status. We assessed factors associated with HIV RNA ≤ 50 and ≤ 400 HIV-1 RNA copies/mL using logistic regression. Because of the strong association between region of randomization and baseline low HIV RNA, analyses were stratified by region. RESULTS: We found that, of 4676 eligible participants randomized in START with a baseline HIV RNA assessment, 113 (2.4%) had HIV RNA ≤ 50 copies/mL at baseline, and a further 257 (5.5%) between 51 and 400 copies/mL. We found that HIV exposure routes other than male homosexual contact, higher high-density lipoprotein (HDL) cholesterol levels, higher CD4 cell counts, and higher CD4:CD8 ratio were associated with increased odds of low HIV RNA. HCV antibody positivity was borderline statistically significantly associated with low HIV RNA. Race and HBV surface antigen positivity were not significantly associated with low HIV RNA. CONCLUSIONS: In a modern cohort of individuals with early untreated HIV infection, we found that HIV exposure routes other than male homosexual contact and higher HDL cholesterol were associated with increased odds of low HIV RNA.

A comparison of computational models with and without genotyping for prediction of response to second-line HIV therapy.

OBJECTIVES: We compared the use of computational models developed with and without HIV genotype vs. genotyping itself to predict effective regimens for patients experiencing first-line virological failure. METHODS: Two sets of models predicted virological response for 99 three-drug regimens for patients on a failing regimen of two nucleoside/nucleotide reverse transcriptase inhibitors and one nonnucleoside reverse transcriptase inhibitor in the Second-Line study. One set used viral load, CD4 count, genotype, plus treatment history and time to follow-up to make its predictions; the second set did not include genotype. Genotypic sensitivity scores were derived and the ranking of the alternative regimens compared with those of the models. The accuracy of the models and that of genotyping as predictors of the virological responses to second-line regimens were compared. RESULTS: The rankings of alternative regimens by the two sets of models were significantly correlated in 60-69% of cases, and the rankings by the models that use a genotype and genotyping itself were significantly correlated in 60% of cases. The two sets of models identified alternative regimens that were predicted to be effective in 97% and 100% of cases, respectively. The area under the receiver-operating curve was 0.72 and 0.74 for the two sets of models, respectively, and significantly lower at 0.55 for genotyping. CONCLUSIONS: The two sets of models performed comparably well and significantly outperformed genotyping as predictors of response. The models identified alternative regimens predicted to be effective in almost all cases. It is encouraging that models that do not require a genotype were able to predict responses to common second-line therapies in settings where genotyping is unavailable.

HIV-related neurocognitive impairment screening: the patient's perspective on its utility and psychological impact.

Despite ever improving advances in antiretroviral therapy, neurocognitive impairments such as asymptomatic and mild neurocognitive impairment remain a significant problem for the HIV-positive population. We distributed a post-neurocognitive impairment screening service evaluation questionnaire to assess satisfaction and anxiety. Subjects were HIV positive and aged 18-50. They were screened using the Brief Neurocognitive Score and International HIV Dementia Score as well as undergoing screening for anxiety (Generalised Anxiety Disorder Assessment [GAD-7]), depression (Participant Health Questionnaire Mood Scale [PHQ-9]) and memory (Everyday Memory Questionnaire [EMQ-R]). On completion, they were either reassured that the tests were normal or were referred for further investigation. Following assessment, subjects were asked to complete an anonymous satisfaction survey; 101 surveys were analysed. Forty-nine per cent of participants stated that they "felt better" following screening, 43% said it "made no difference", 6% stated it "worried me" and 1% "did not understand". On a scale of 0-10 of helpfulness, the mean score was 7.53. Forty-seven subjects indicated that they were referred for further investigation and 46 subjects that nothing else was needed; 8 reported they did not know. Those referred on rated satisfaction at a mean of 7.54/10 and those with normal screen as 7.09/10 (p = 0.46). Of the groups that were referred for further investigation, 6% said the test "worried them" compared to 4% in the non-referred group. Forty-nine per cent said they "felt better" despite an abnormal result compared to 50% in a normal screening result (p = 0.76). The results of this survey show that screening for neurocognitive impairment by this method is acceptable and helpful to participants. It did not lead to an increase in anxiety and there was no correlation between referred for further investigations and anxiety suggesting concerns about creating undue anxiety by screening and referral are unfounded.

Screening for HIV-related neurocognitive impairment in clinical practice: challenges and opportunities.

With increasingly successful management of HIV, focus has shifted away from AIDS-related complications to other chronic co-morbidities. For HIV-related cognitive problems, the true aetiopathogenesis and epidemiology remains unclear. Rather than a systematic review, this paper presents the challenges and the opportunities we faced in establishing our own clinical service. Papers were identified using Pubmed and the terms "screening", "HIV" and "neurocognitive". This article covers the background of HIV-associated neurocognitive disorders (HAND) with a focus on HIV-related neurocognitive impairment (NCI), detailing classification, prevalence, diagnostic categories and diagnostic uncertainties. Screening is discussed, including a comparison of the available screening tools for cognitive deficits in HIV-infected patients and the importance of practice effects. Discussed also are the normal ranges and the lack thereof and potential investigations for those found to have impairments. We conclude by discussing the role of NCI screening in routine clinical care at the current time.

The immunomodulatory nutritional intervention NR100157 reduced CD4+ T-cell decline and immune activation: a 1-year multicenter randomized controlled double-blind trial in HIV-infected persons not receiving antiretroviral therapy (The BITE Study).

BACKGROUND: The immunomodulatory nutritional product NR100157 was developed for human immunodeficiency virus (HIV)-infected individuals. We hypothesized that targeting the compromised gastrointestinal tract of HIV-infected individuals would result in systemic immunological benefits. METHODS: In a multicenter, randomized, controlled, double-blind trial, 340 HIV-1-positive adults not on antiretroviral therapy, with CD4(+) T-cell counts <800/µL, were given either NR100157 or an isocaloric and isonitrogenous control for 52 weeks. Primary outcome was CD4(+) T-cell count. Secondary outcomes included plasma viral load (pVL), safety, and tolerability. In a pilot study (n = 20), levels of CD4(+)CD25(+) and CD8(+)CD38(+) activation were measured (n = 20). The trial is registered at the Dutch Trial Register (NTR886) and ISRCTN81868024. RESULTS: At 52 weeks, CD4(+) T-cell decline showed a 40-cell/µL difference (P = .03) in the intention-to-treat population in favor of the immunomodulatory NR100157 (control vs active, -68 ± 15 vs -28 ± 16 cells/µL/year). The change in pVL from baseline was similar between groups (P = .81). In the pilot study, the percentage of CD4(+)CD25(+) was lower in the active group (P < .05) and correlated with changes in CD4(+) T-cell count (r = -0.55, P < .05). The percentage of CD8(+)CD38(+) levels was unaffected. CONCLUSIONS: The specific immunonutritional product NR100157 significantly reduces CD4(+) decline in HIV-1-infected individuals, and this is associated with decreased levels of CD4(+)CD25(+). (This nutritional intervention is likely to affect local gut integrity and gut-associated lymphoid tissue homeostasis, which in turn translates positively to systemic effects.) Clinical Trials Registration. ISRCTN81868024.

The incidence of AIDS-defining illnesses at a current CD4 count ≥ 200 cells/µL in the post-combination antiretroviral therapy era.

BACKGROUND: Few studies consider the incidence of individual AIDS-defining illnesses (ADIs) at higher CD4 counts, relevant on a population level for monitoring and resource allocation. METHODS: Individuals from the Collaboration of Observational HIV Epidemiological Research Europe (COHERE) aged ≥14 years with ≥1 CD4 count of ≥200 µL between 1998 and 2010 were included. Incidence rates (per 1000 person-years of follow-up [PYFU]) were calculated for each ADI within different CD4 strata; Poisson regression, using generalized estimating equations and robust standard errors, was used to model rates of ADIs with current CD4 ≥500/µL. RESULTS: A total of 12 135 ADIs occurred at a CD4 count of ≥200 cells/µL among 207 539 persons with 1 154 803 PYFU. Incidence rates declined from 20.5 per 1000 PYFU (95% confidence interval [CI], 20.0-21.1 per 1000 PYFU) with current CD4 200-349 cells/µL to 4.1 per 1000 PYFU (95% CI, 3.6-4.6 per 1000 PYFU) with current CD4 ≥ 1000 cells/µL. Persons with a current CD4 of 500-749 cells/µL had a significantly higher rate of ADIs (adjusted incidence rate ratio [aIRR], 1.20; 95% CI, 1.10-1.32), whereas those with a current CD4 of ≥1000 cells/µL had a similar rate (aIRR, 0.92; 95% CI, .79-1.07), compared to a current CD4 of 750-999 cells/µL. Results were consistent in persons with high or low viral load. Findings were stronger for malignant ADIs (aIRR, 1.52; 95% CI, 1.25-1.86) than for nonmalignant ADIs (aIRR, 1.12; 95% CI, 1.01-1.25), comparing persons with a current CD4 of 500-749 cells/µL to 750-999 cells/µL. DISCUSSION: The incidence of ADIs was higher in individuals with a current CD4 count of 500-749 cells/µL compared to those with a CD4 count of 750-999 cells/µL, but did not decrease further at higher CD4 counts. Results were similar in patients virologically suppressed on combination antiretroviral therapy, suggesting that immune reconstitution is not complete until the CD4 increases to >750 cells/µL.

Pancreatic insufficiency in patients with HIV infection: role of didanosine questioned.

OBJECTIVES: The aim of the study was to identify possible causes of pancreatic insufficiency in patients with HIV infection. METHODS: A retrospective analysis of 233 HIV-positive patients for whom faecal elastase measurement was available was performed to investigate potential associations with core demographic data, HIV infection characteristics, degree of immunosuppresion, exposure to antiretroviral therapy (ART), alcohol misuse, diabetes, hepatitis C virus (HCV) infection, triglyceride and cholesterol levels and symptomatology. The response to pancreatic enzyme replacement for patients with evidence of insufficiency was also evaluated. RESULTS: Of 233 patients, 104 (45%) had evidence of pancreatic exocrine insufficiency (faecal elastase < 200 mcg/g). A positive association with exocrine pancreatic insufficiency was found for HCV infection (P = 0.007), previous or current HCV treatment (P = 0.003), alcohol misuse history (P = 0.006) and the presence of steatorrhoea (P = 0.03). There was no demonstrated association between exocrine pancreatic insufficiency and didanosine (ddI) exposure (P = 0.43) or stavudine (d4T) exposure (P = 0.62). Seventy-seven per cent of patients who were treated with pancreatic enzymatic supplementation reported a subjective improvement in symptoms. CONCLUSIONS: Faecal elastase sampling should form part of the routine work-up for HIV-positive patients with chronic diarrhoea even in the absence of 'traditional' risk factors such as ddI exposure. In particular, if the patient has steatorrhoea, a history of alcohol exposure or their HCV serology is positive, they should be considered for investigation. Treatment with pancreatic enzyme supplementation appears to be effective in the treatment of chronic diarrhoea caused by pancreatic insufficiency in the majority of patients.

Comparison of two cohorts of patients presenting with AIDS: patients with previously known HIV diagnoses and true late presenters.

OBJECTIVES: We aimed to identify the factors associated with developing AIDS 6 months or more after an HIV diagnosis, and to examine how post-HIV diagnosis AIDS (PHDA) patients differed from true late presenters (HIV diagnosed concurrent with the first AIDS presenting event) in their demographics and comorbidities. METHODS: A retrospective analysis was undertaken of all inpatients admitted to a large HIV unit presenting with the following AIDS-defining infections: cryptococcal meningitis, cerebral toxoplasmosis or Pneumocystis jirovecii pneumonia between 1 January 2005 and 31 December 2010. RESULTS: 114 HIV-positive patients presented with AIDS-defining infections. Compared with late presenters, PHDA patients had a larger proportion of migrants and visitors (53.7% vs. 34.0%, p=0.047), were more likely to inject drugs (9.3% vs 0.0%, p=0.032), had more previous HIV-associated diseases (57.4% vs. 12.8%, p=0.000), psychiatric comorbidities (35.2% vs. 12.8%, p=0.009), rates of alcohol abuse (24.1% vs. 4.3%, p=0.005) and reported social issues (25.9% vs. 0.00%, p=0.000). 88.9% of PHDA patients were lost to follow-up for a period of at least 4 months since diagnosis. Common reasons for clinic non-attendance included travel, social issues, transfer of care and treatment avoidance. Common reasons for antiretroviral treatment breaks included drug side effects, negative beliefs about medication, incompatible lifestyles and social issues. CONCLUSIONS: Compared with late presenters, PHDA patients demonstrate clear demographical differences including higher rates of psychiatric comorbidities, social issues, alcohol and substance abuse. Many PHDA patients default follow-up. The retention of HIV patients in care and on treatment must be addressed by clinicians to prevent avoidable morbidity.

Chemoradiotherapy for anal cancer in HIV patients causes prolonged CD4 cell count suppression.

BACKGROUND: Despite the advent of highly active antiretroviral therapy, anal cancer remains a significant health problem in human immunodeficiency virus (HIV) patients. We present the clinical features and treatment outcomes of anal cancer in 60 HIV-positive patients over a 20-year period. PATIENTS AND METHODS: A prospective database of all HIV-positive individuals managed in a specialist unit since 1986 includes 11 112 patients (71 687 person-years of follow-up). Sixty patients with anal cancer were identified. Their clinicopathological and treatment details were analysed. RESULTS: At anal cancer diagnosis, the mean age was 44 years (range: 28-75 years) and the median CD4 cell count was 305 mm(-3) (range: 16-1252 mm(-3)). Fifty (83%) had chemoradiotherapy (CRT). Forty-six (92%) responded, of whom 10 (22%) subsequently relapsed with locoregional (70%), metastatic disease (10%) or both (20%). The overall 5-year survival is 65% (95% confidence interval 51% to 78%). The median CD4 count fell from 289 mm(-3) before CRT to 132 mm(-3) after 3 months and to 189 mm(-3) after 1 year (P<0.05). Six patients in remission of anal cancer died of acquired immunodeficiency syndrome defining illnesses. CONCLUSIONS: The management of anal cancer with CRT achieves similar outcomes as the general population. CRT is associated with significant prolonged CD4 suppression that may contribute to late deaths of patients in remission.

Non-uptake of highly active antiretroviral therapy among patients with a CD4 count < 350 cells/µL in the UK.

OBJECTIVES: Current British HIV Association (BHIVA) guidelines recommend that all patients with a CD4 count <350 cells/µL are offered highly active antiretroviral therapy (HAART). We identified risk factors for delayed initiation of HAART following a CD4 count <350 cells/µL. METHODS: All adults under follow-up in 2008 who had a first confirmed CD4 count <350 cells/µL from 2004 to 2008, who had not initiated treatment and who had >6 months of follow-up were included in the study. Characteristics at the time of the low CD4 cell count and over follow-up were compared to identify factors associated with delayed HAART uptake. Analyses used proportional hazards regression with fixed (sex/risk group, age, ethnicity, AIDS, baseline CD4 cell count and calendar year) and time-updated (frequency of CD4 cell count measurement, proportion of CD4 counts <350 cells/µL, latest CD4 cell count, CD4 percentage and viral load) covariates. RESULTS: Of 4871 patients with a confirmed low CD4 cell count, 436 (8.9%) remained untreated. In multivariable analyses, those starting HAART were older [adjusted relative hazard (aRH)/10 years 1.15], were more likely to be female heterosexual (aRH 1.13), were more likely to have had AIDS (aRH 1.14), had a greater number of CD4 measurements < 350 cells/µL (aRH/additional count 1.18), had a lower CD4 count over follow-up (aRH/50 cells/µL higher 0.57), had a lower CD4 percentage (aRH/5% higher 0.90) and had a higher viral load (aRH/log(10) HIV-1 RNA copies/ml higher 1.06). Injecting drug users (aRH 0.53), women infected with HIV via nonsexual or injecting drug use routes (aRH 0.75) and those of unknown ethnicity (aRH 0.69) were less likely to commence HAART. CONCLUSION: A substantial minority of patients with a CD4 count < 350 cells/µL remain untreated despite its indication.

British HIV Association and Children's HIV Association position statement on infant feeding in the UK 2011.

To prevent the transmission of HIV infection during the postpartum period, the British HIV Association and Children's HIV Association (BHIVA/CHIVA) continue to recommend the complete avoidance of breast feeding for infants born to HIV-infected mothers, regardless of maternal disease status, viral load or treatment.

Responses to highly active antiretroviral therapy and clinical events in patients with a low CD4 cell count: late presenters vs. late starters.

OBJECTIVE: We investigated whether adverse responses to highly active antiretroviral therapy (HAART) associated with late HIV presentation are secondary to low CD4 cell count per se or other confounding factors. METHODS: A longitudinal analysis of the UK Collaborative HIV Cohort (CHIC) Study of individuals starting HAART in 1998-2007 was carried out, comparing late presenters (presenting/starting HAART at a CD4 count <200 cells/µL) with late starters (presenting at a CD4 count>350 cells/µL; starting HAART at a CD4 count<200 cells/µL), using 'ideal starters' (presenting at a CD4 count>350 cells/µL; starting HAART at a CD4 count of 200-350 cells/µL) as a comparator. Virological, immunological and clinical (new AIDS event/death) outcomes at 48 and 96 weeks were analysed, with the analysis being limited to those remaining on HAART for>3 months. RESULTS: A total of 4978 of 9095 individuals starting first-line HAART with HIV RNA>500 HIV-1 RNA copies/mL were included in the analysis: 2741 late presenters, 947 late starters and 1290 ideal starters. Late presenters were more commonly female, heterosexual and Black African. Most started nonnucleoside reverse transcriptase inhibitors (NNRTIs); 48-week virological suppression was similar in late presenters and starters (and marginally lower than in ideal starters); by week 96 differences were reduced and nonsignificant. The median CD4 cell count increase in late presenters was significantly lower than that in late starters (weeks 48 and 96). During year 1, new clinical events were more frequent for late presenters [odds ratio (OR) 2.04; 95% confidence interval (CI) 1.19-3.51; P=0.01]; by year 2, event rates were similar in all groups. CONCLUSION: Amongst patients who initiate, and remain on, HAART, late presentation is associated with lower rates of virological suppression, blunted CD4 cell count increases and more clinical events compared with late starters in year 1, but similar clinical and immunological outcomes by year 2 to those of both late and ideal starters. Differences between late presenters and late starters suggest that factors other than CD4 cell count alone may be driving adverse treatment outcomes in late-presenting individuals.

Long-term trends in CD4 cell counts and impact of viral failure in individuals starting antiretroviral therapy: UK Collaborative HIV Cohort (CHIC) study.

OBJECTIVE: The aim of the study was to describe trends in CD4 cell counts in HIV-infected patients after initiation of combination antiretroviral therapy (cART), according to CD4 cell count at initiation (baseline), and to quantify the implications of virological failure for these trends. METHODS: Eligible participants from the UK Collaborative HIV Cohort (CHIC) were antiretroviralnaïve and started cART after 1997. Random effects were used to model CD4 cell count trends, accounting for multiple measurements within participants. We assessed whether CD4 cell count trends varied according to baseline CD4 cell count and separately in participants with and without post-cART virological failure. Effects of post-cART virological failure (>1000 HIV-1 RNA copies/mL) on subsequent CD4 cell counts were evaluated. FINDINGS: A total of 7069 participants were included in the analysis (median follow-up in all baseline CD4 cell count groups was ≥ 35 months). Among participants without virological failure ≥ 6 months after the start of cART, CD4 cell counts continued to increase up to 8 years, with little evidence that differences between baseline CD4 cell count groups diminished over time. Virological failure ≥ 6 months after the start of cART was associated with lower subsequent CD4 cell counts, with greater CD4 cell count reduction for more recent virological failure and higher viral load. CONCLUSIONS: Post-cART CD4 cell counts are strongly related to pre-cART CD4 cell counts. CD4 cell count recovery is greatest in individuals who can avoid viral loads >1000 copies/mL while on cART.

Persistence of episomal HIV-1 infection intermediates in patients on highly active anti-retroviral therapy.

Treatment of HIV-1-infected individuals with a combination of anti-retroviral agents results in sustained suppression of HIV-1 replication, as evidenced by a reduction in plasma viral RNA to levels below the limit of detection of available assays. However, even in patients whose plasma viral RNA levels have been suppressed to below detectable levels for up to 30 months, replication-competent virus can routinely be recovered from patient peripheral blood mononuclear cells and from semen. A reservoir of latently infected cells established early in infection may be involved in the maintenance of viral persistence despite highly active anti-retroviral therapy. However, whether virus replication persists in such patients is unknown. HIV-1 cDNA episomes are labile products of virus infection and indicative of recent infection events. Using episome-specific PCR, we demonstrate here ongoing virus replication in a large percentage of infected individuals on highly active anti-retroviral therapy, despite sustained undetectable levels of plasma viral RNA. The presence of a reservoir of 'covert' virus replication in patients on highly active anti-retroviral therapy has important implications for the clinical management of HIV-1-infected individuals and for the development of virus eradication strategies.

Discordant responses on starting highly active antiretroviral therapy: suboptimal CD4 increases despite early viral suppression in the UK Collaborative HIV Cohort (UK CHIC) Study.

OBJECTIVES: Patients starting highly active antiretroviral therapy (HAART) may have a suboptimal CD4 increase despite rapid virological suppression. The frequency and the significance for patient care of this discordant response are uncertain. This study was designed to determine the incidence of a discordant response at two time-points, soon after 6 months and at 12 months, and to determine the relationship with clinical outcomes. METHODS: Data obtained in the UK Collaborative HIV Cohort Study were analysed. A total of 2584 treatment-naïve patients starting HAART with HIV viral load (VL) > 1000 HIV-1 RNA copies/mL at baseline and < 50 copies/mL within 6 months were included in the analysis. Patients were classified at either 6-10 (midpoint 8) months or 10-14 (midpoint 12) months as having a discordant (CD4 count increase < 100 cells/microL from baseline) or concordant response (CD4 count increase >or= 100 cells/microL). RESULTS: Discordant responses occurred in 32.1% of patients at 8 months and in 24.2% at 12 months; 35% of those discordant at 8 months were concordant at 12 months. A discordant response was associated with older age, lower baseline VL, and (at 12 months) higher baseline CD4 cell count. In a multivariate analysis it was associated with an increased risk of death, more strongly at 12 months [incidence rate ratio (IRR) 3.35, 95% confidence interval (CI) 1.73-6.47, P < 0.001] than at 8 months (IRR 2.08, 95% CI 1.19-3.64, P = 0.010), but not with new AIDS events. CONCLUSIONS: Discordant responders have a worse outcome, but assessment at 12 months may be preferred, given the number of 'slow' responders. Management strategies to improve outcomes for discordant responders need to be investigated.

The prevalence of hepatitis C virus (HCV) infection in HIV-positive individuals in the UK - trends in HCV testing and the impact of HCV on HIV treatment outcomes.

We examined the prevalence of hepatitis C virus (HCV) infection among HIV-positive individuals in the UK, trends in HCV testing and the impact of HCV on HIV treatment outcomes. Trends over time in HCV prevalence were calculated using each patient's most recent HCV status at the end of each calendar year. Logistic regression was used to identify factors associated with having a HCV antibody test, and Cox regression was used to determine whether HCV status was associated with the time to experiencing an immunological response to highly active antiretroviral treatment (HAART), time to virological response and viral rebound. Of the 31,765 HIV-positive individuals seen for care between January 1996 and September 2007, 20,365 (64.1%) individuals were tested for HCV, and 1807 (8.9%) had detectable HCV antibody. The proportion of patients in follow-up ever tested for HCV increased over time, from 782/8505 (9.2%) in 1996 to 14,280/17,872 (79.9%) in 2007. Nine thousand six hundred and sixty-nine individuals started HAART for the first time in or after January 2000, of whom, 396 (4.1%) were HCV positive. Presence of HCV infection did not affect initial virological response, virological rebound or immunological response. The cumulative prevalence of HCV in the UK CHIC Study is 8.9%. Despite UK guidelines, over 20% of HIV-positive individuals have not had their HCV status determined by 2007. HCV infection had no impact on HIV virological outcomes or immunological response to HIV treatment. The long-term impact on morbidity and mortality remain to be determined.