Observational cohort study of rilpivirine (RPV) utilization in Europe.

INTRODUCTION: Data on safety and effectiveness of RPV from the real-world setting as well as comparisons with other NNRTIs such as efavirenz (EFV) remain scarce. METHODS: Participants of EuroSIDA were included if they had started a RPV- or an EFV-containing regimen over November 2011-December 2017. Statistical testing was conducted using non-parametric Mann-Whitney U test and Chi-square test. A logistic regression model was used to compare participants' characteristics by treatment group. Kaplan-Meier analysis was used to estimate the cumulative risk of virological failure (VF, two consecutive values > 50 copies/mL). RESULTS: 1,355 PLWH who started a RPV-based regimen (11% ART-naïve), as well as 333 initiating an EFV-containing regimen were included. Participants who started RPV differed from those starting EFV for demographics (age, geographical region) and immune-virological profiles (CD4 count, HIV RNA). The cumulative risk of VF for the RPV-based group was 4.5% (95% CI 3.3-5.7%) by 2 years from starting treatment (71 total VF events). Five out of 15 (33%) with resistance data available in the RPV group showed resistance-associated mutations vs. 3/13 (23%) among those in the EFV group. Discontinuations due to intolerance/toxicity were reported for 73 (15%) of RPV- vs. 45 (30%) of EFV-treated participants (p = 0.0001). The main difference was for toxicity of central nervous system (CNS, 3% vs. 22%, p < 0.001). CONCLUSION: Our estimates of VF > 50 copies/mL and resistance in participants treated with RPV were similar to those reported by other studies. RPV safety profile was favourable with less frequent discontinuation due to toxicity than EFV (especially for CNS).

Dynamics of hepatitis C epidemic among people living with HIV in Estonia based on Estonian HIV cohort study.

BACKGROUND: Estonia has a typical Eastern European HIV epidemic where the most frequent co-infection is chronic hepatitis C (HCV). We aimed to describe the changes in HCV prevalence, the distribution of HCV genotypes (GT), and HCV treatment in Estonian people living with HIV over 15 years. METHODS: We used data of subjects included to the Estonian HIV Cohort Study (E-HIV) before 31st of December 2015. We compared two time periods-first, 1st of January 2000 to 31st of December 2008 when the HIV epidemic was mostly spreading among people who inject drugs (PWID) and second, 1st of January 2009 to 31st of December 2015 when HIV started to emerge to the general population. RESULTS: Of 4422 HIV positives 3708 (84%) had information about their HCV serostatus; 2706 (61%) were HCV seropositive, of latter 1625 (60%) were HCV RNA positive, 239 (9%) had their HCV GT determined, and 141 (5%) received treatment for HCV. The dominating subtypes were 1b (42%) and 3a (37%) followed by 1a (16%), and the few cases of 2 (1.5%). HCV prevalence was 1.5 times (95% CI 1.4-1.6) higher in subjects diagnosed with HIV in first as compared to those diagnosed in second period (84% vs 56%, respectively). There were more men and the median age at HIV diagnosis was lower in HIV/HCV co-infected than in HIV mono-infected patients (70% vs 47% and 24 years vs. 30 years, respectively; both p < 0.001). CONCLUSION: There is a decrease in HCV prevalence but it remains high among HIV positive PWID, suggesting that there is need for improvement of harm reduction programs among PWID.

Persistent disparities in antiretroviral treatment (ART) coverage and virological suppression across Europe, 2004 to 2015.

BACKGROUND: Direct comparisons between countries in core HIV care parameters are often hampered by differences in data collection. AIM: Within the EuroSIDA study, we compared levels of antiretroviral treatment (ART) coverage and virological suppression (HIV RNA < 500 copies/mL) across Europe and explored temporal trends. METHODS: In three cross-sectional analyses in 2004-05, 2009-10 and 2014-15, we assessed country-specific percentages of ART coverage and virological suppression among those on ART. Temporal changes were analysed using logistic regression. RESULTS: Overall, the percentage of people on ART increased from 2004-05 (67.8%) to 2014-15 (78.2%), as did the percentage among those on ART who were virologically suppressed (75.2% in 2004-05, 87.7% in 2014-15). However, the rate of improvement over time varied significantly between regions (p < 0.01). In 2014-15, six of 34 countries had both ART coverage and virological suppression of above 90% among those on ART. The pattern varied substantially across clinics within countries, with ART coverage ranging from 61.9% to 97.0% and virological suppression from 32.2% to 100%. Compared with Western Europe (as defined in this study), patients in other regions were less likely to be virologically suppressed in 2014-15, with the lowest odds of suppression (adjusted odds ratio = 0.16; 95% confidence interval (CI): 0.13-0.21) in Eastern Europe. CONCLUSIONS: Despite overall improvements over a decade, we found persistent disparities in country-specific estimates of ART coverage and virological suppression. Underlying reasons for this variation warrant further analysis to identify a best practice and benchmark HIV care across EuroSIDA.

No transmitted drug resistance to HIV integrase strand-transfer inhibitors after their scale-up in Estonia in 2017.

OBJECTIVES: In Eastern Europe, HIV-1 transmitted drug resistance (TDR) data, especially in the integrase (IN) region, are limited. In Estonia, INSTI (integrase strand transfer inhibitors) TDR has been studied only prior to the INSTI scale-up in late 2010s. The current study aimed to determine the levels of protease (PR), reverse transcriptase (RT) and IN surveillance drug resistance mutations (SDRMs) among newly diagnosed patients in Estonia in 2017. METHODS: The study included 216 newly diagnosed HIV-1 individuals from 1 January until 31 December 2017 in Estonia. Demographic and clinical data were obtained from the Estonian Health Board, the Estonian HIV Cohort Study (E-HIV) and clinical laboratories' databases. The PR-RT and IN regions were sequenced and analysed for SDRMs and subtype determination. RESULTS: Seventy-one percent (151/213) of available HIV-positive samples were successfully sequenced. The overall level of TDR was 7.9% (12/151; 95% CI 4.4%-13.8%); no dual or triple class resistance was detected. No major INSTI mutations were found. The distribution of SDRMs for NNRTI, NRTI and PI was 5.9% (9/151), 1.3% (2/151) and 0.7% (1/151), respectively. The predominant NNRTI mutation was K103N. CRF06_cpx was the predominant variant (59%) in the Estonian HIV-1 population, followed by subtype A (9%) and subtype B (8%). CONCLUSION: Although no major INSTI mutations were found, close monitoring of INSTI SDRMs is needed considering the extensive use of the first- and second-generation INSTIs. PR-RT TDR is slowly rising in Estonia, indicating the need for continuous surveillance in the future. Low genetic barrier NNRTIs should be avoided in the treatment regimens.

Incidence and risk factors for suicide, death due to substance use, and violent/accidental death in people with HIV.

OBJECTIVE: Deaths due to suicide, substance use and violence/accident may reflect similar risk factors and overlap in their classification. This study aimed to investigate incidence and risk factors of mortality among people with HIV (PWH) due to these three related causes. DESIGN: Prospectively collected data from PWH at least 18 years old and under active follow-up in the EuroSIDA study from 2007 to 2019 were analysed. METHODS: Cause-specific Cox regression analysis was used to assess risk factors. RESULTS: A total of 17 881 participants were included, comprising 149 327 person-years of follow-up (PYFU). Forty participants died by suicide {incidence rate [IR] [95% confidence interval (CI)]: 0.3/1000 PYFU (0.2, 0.4)} 93 from substance use [IR (95% CI): 0.6/1000 PYFU (0.5, 0.8)], and 57 by violence/accident [IR (95% CI): 0.4/1000 PYFU (0.3, 0.5)]. An AIDS diagnosis within the last 12 months was associated with nine-fold increased risk of suicide vs. no history of AIDS [adjusted hazard ratio (aHR): 9.06; 95% CI: 2.07, 39.7]. Male gender was associated with double the risk of violent/accidental death (aHR: 2.28; 95% CI: 1.09, 4.78). PWH in Eastern Europe and those who acquired HIV by injection drug use (IDU) demonstrated a greater risk of death due to substance use or violence/accident. CONCLUSIONS: The association between a recent diagnosis of AIDS and suicide highlights a critical period for intervention. HIV infection acquired through IDU demonstrated an expected relationship with death due to substance use and violent/accidental deaths. Increased risk of death due to substance use and violence/accident in Eastern Europe demands investigation into specific differences that may drive that association.

Uptake of hepatitis C virus treatment in HIV/hepatitis C virus-coinfected patients across Europe in the era of direct-acting antivirals.

BACKGROUND AND AIMS: To investigate the uptake of hepatitis C virus (HCV) therapy among HIV/HCV-coinfected patients in the pan-European EuroSIDA study between 2011 and 2016. METHODS: All HCV-RNA+ patients were included. Baseline was defined as latest of anti-HCV+, January 2011 or enrolment in EuroSIDA. The incidence of starting first interferon-free direct-acting antiviral (DAA) therapy was calculated. Factors associated with starting interferon-free DAA were determined by Poisson regression. RESULTS: Among 4308 HCV-RNA+ patients (1255, 970, 663, 633, 787 from South, West, North, Central East and East Europe, respectively) with 11 863 person-years of follow-up, 1113 (25.8%) started any HCV therapy. Among patients with at least F3 fibrosis, more than 50% in all regions remained untreated. The incidence (per 1000 person-years of follow-up, 95% confidence interval) of starting DAA increased from 7.8 (5.9-9.8) in 2014 to 135.2 (122.0-148.5) in 2015 and 128.9 (113.5-144.3) in 2016. The increase was highest in North and West and intermediate in South, but remained modest in Central East and Eastern Europe. After adjustment, women, individuals from Central East or East, genotype 3, antiretroviral therapy naïve and those with detectable HIV-RNA were less likely to start DAA. Older persons, those with HCV-RNA more than 500 000 IU/ml and those with more advanced liver fibrosis were more likely to start DAA. CONCLUSION: Uptake of DAA therapy among HIV/HCV-coinfected patients increased considerably in Western Europe between 2014 and 2016, but was modest in Central East and East. In all regions more than 50% with at least F3 fibrosis remained untreated. Women were less likely to start DAA.

Chronic renal failure among HIV-1-infected patients.

BACKGROUND: The role of exposure to antiretrovirals in chronic renal failure (CRF) is not well understood. Glomerular filtration rates (GFR) are estimated using the Cockcroft-Gault (CG) or Modification of Diet in Renal Disease (MDRD) equations. METHODS: Baseline was arbitrarily defined as the first recorded GFR; patients with two consecutive GFR < or = 60 ml/min per 1.73 m(2) were defined as having CRF. Logistic regression was used to determine odds ratio (OR) of CRF at baseline. ART exposure (yes/no or cumulative exposure) prior to baseline was included in multivariate models (adjusted for region of Europe, age, prior AIDS, CD4 cell count nadir, viral load, hypertension and use of nephrotoxic anti-infective therapy). RESULTS: Using CG, the median GFR at baseline (n = 4474) was 94.4 (interquartile range, 80.5-109.3); 158 patients (3.5%) had CRF. Patients with CRF were older (median, 61.9 versus 43.1 years), had lower CD4 cell count nadirs (median, 80 versus 137 cells/microl), and were more likely to be diagnosed with AIDS (44.3 versus 30.4%), diabetes (16.5 versus 4.3%) or hypertension (53.8 versus 26.4%), all P < 0.001. In a multivariate model any use of indinavir [odds ratio (OR) 2.49; 95% confidence interval (CI), 1.62-3.83] or tenofovir (OR, 2.18; 95% CI, 1.25-3.81) was associated with increased odds of CRF, as was cumulative exposure to indinavir (OR, 1.15 per year of exposure; 95% CI, 1.06-1.25) or tenofovir (OR, 1.60; 95% CI, 1.20-2.15). Highly consistent results were seen using the MDRD formula. CONCLUSIONS: Among antiretrovirals, only exposure to indinavir or tenofovir was associated with increased odds of CRF. We used a confirmed low GFR to define CRF to increase the robustness of our analysis, although there are several potential biases associated with this cross-sectional analysis.

Short-term clinical disease progression in HIV-1-positive patients taking combination antiretroviral therapy: the EuroSIDA risk-score.

OBJECTIVES: To derive and validate a clinically applicable prognostic score for predicting short-term disease progression in HIV-infected patients taking combination antiretroviral therapy (cART). DESIGN AND METHODS: Poisson regression was used to identify prognostic markers for new AIDS/death in patients taking cART. A score was derived for 4169 patients from EuroSIDA and validated on 5150 patients from the Swiss HIV Cohort Study (SHCS). RESULTS: In EuroSIDA, 658 events occurred during 22 321 person-years of follow-up: an incidence rate of 3.0/100 person-years of follow-up [95% confidence interval (CI), 2.7-3.3]. Current levels of viral load, CD4 cell count, CD4 cell slope, anaemia, and body mass index all independently predicted new AIDS/death, as did age, exposure group, a prior AIDS diagnosis, prior antiretroviral treatment and stopping all antiretroviral drugs. The EuroSIDA risk-score was divided into four strata; a patient in the lowest strata would have predicted chance of new AIDS/death of 1 in 801, 1 in 401 and 1 in 201 within the next 3, 6 or 12 months, respectively. The corresponding figures for the highest strata were 1 in 17, 1 in 9 and 1 in 5, respectively. A single-unit increase in the risk-score was associated with a 2.70 times higher incidence of clinical progression (95% CI, 2.56-2.84) in EuroSIDA and 2.88 (95% CI, 2.75-3.02) in SHCS. CONCLUSIONS: A clinically relevant prognostic score was derived in EuroSIDA and validated within the SHCS, with good agreement. The EuroSIDA risk-score will be made available publicly via an interface that will perform all calculations for the individual.

The HIV prevention needs of injection drug users in Estonia.

To assess the relationships between HIV transmission risk behaviours, HIV serostatus and knowledge of HIV serostatus among active injection drug users (IDUs) residing in Tallinn, Estonia, we conducted HIV testing and administered a standardized interview to 266 participants reporting recent injection drug use. In total, 45% were HIV positive, and of those, 39% knew their HIV serostatus. Those who knew their HIV-positive serostatus were less likely to report giving someone else their needle after they used it (9%) than were HIV-negative participants (23%) and those who were HIV positive but unaware of their HIV-positive serostatus (25%). There were no statistically significant differences in unprotected sex or other drug use behaviours between the groups. Most participants reported that HIV can be transmitted through sharing needles (98%) and unprotected sexual activity (93%). Prevention needs of IDUs in this area include increasing the rates of HIV testing and implementing effective programmes to reduce sexual and drug use risk behaviours.

Plasma HIV-1 Tropism and the Risk of Short-Term Clinical Progression to AIDS or Death.

OBJECTIVE: To investigate if plasma HIV-1 tropism testing could identify subjects at higher risk for clinical progression and death in routine clinical management. DESIGN: Nested case-control study within the EuroSIDA cohort. METHODS: Cases were subjects with AIDS or who died from any cause, with a plasma sample with HIV-1 RNA >1000 copies/mL available for tropism testing 3 to 12 months prior to the event. At least 1 control matched for age, HIV-1 RNA and HCV status at the time of sampling were selected per each case. Conditional logistic regression was used to investigate exposures associated with clinical progression to AIDS or death. A linear mixed model with random intercept was used to compare CD4+T-cell slopes by HIV tropism over the 12 months following the date of sampling. RESULTS: The study included 266 subjects, 100 cases and 166 controls; one quarter had X4 HIV; 26% were ART-naïve. Baseline factors independently associated with clinical progression or death were female gender (OR = 2.13 vs. male, 95CI = 1.04, 4.36), p = 0.038), CD4+T-cell count (OR = 0.90 (95CI = 0.80, 1.00) per 100 cells/mm3 higher, p = 0.058), being on ART (OR = 2.72 vs. being off-ART (95CI = 1.15, 6.41), p = 0.022) and calendar year of sample [OR = 0.84 (95CI = 0.77, 0.91) per more recent year, p<0.001). Baseline tropism was not associated with the risk of clinical progression or death. CD4+T-cell slopes did not differ within or between tropism groups. CONCLUSIONS: The predictive role of plasma tropism determined using 454 sequencing in the context of people receiving cART with detectable VL is not helpful to identify subjects at higher risk for clinical progression to AIDS or death.

HIV-1 subtypes and response to combination antiretroviral therapy in Europe.

BACKGROUND: Combination antiretroviral therapy (cART) may vary in ability to suppress viral load and increase CD4+ T-cell count in people infected with different HIV-1 subtypes, possibly due to differences in resistance development. Antiretroviral drugs have predominantly been developed in Western Europe/North America on the basis of the most prevalent subtype, B. However, non-B subtypes are increasingly spreading worldwide. OBJECTIVE: To compare virological and immunological response to cART between patients infected with B and non-B subtypes across Europe. DESIGN: EuroSIDA prospective, observational cohort with 11,928 HIV-1-infected patients. METHODS: Response to cART was analysed in patients with subtypes determined pre-cART, via multivariable logistic regression on the first measurements 6-12 months after starting cART. A virological response was defined as a viral load <500 copies/mi and immunological response as a CD4+ T-cell count increase of > or =100 cells/mm(3). RESULTS: Forty-five percent of patients were antiretroviral naive at initiation of cART. Virological suppression was achieved by 58% of 689 subtype-B-infected patients and 66% of 102 non-B-infected patients (P=0.159). After adjustment for potential confounders, there was no significant difference in odds of achieving virological suppression (non-B compared with B; odds ratio [OR]: 1.05, 95% confidence interval [CI]: 0.58-1.93, P=0.866). An immunological response was achieved by 43% of 753 B-infected patients and 48% of 114 non-B-infected patients (P=0.334). After adjustment, there was no significant difference in odds of an immunological response (OR: 1.17, 95% CI: 0.73-1.87, P=0.524). CONCLUSIONS: There was no evidence of significant differences in virological or immunological response to cART between patients infected with HIV-1 B and non-B subtypes.

Design and structure of the Estonian HIV Cohort Study (E-HIV).

BACKGROUND: Estonia is experiencing the new Eastern Europe human immunodeficiency virus (HIV) epidemic, with the highest incidence of new infections in the EU. We describe demographic changes, HIV-related laboratory parameters and co-infections during the concentrated HIV epidemic using the Estonian HIV Cohort Study (E-HIV) database, founded in 2009. METHODS: All 3750 subjects in the E-HIV database on December 31, 2013 were included. Subjects were divided into risk groups: people who inject drugs (PWIDs), sexual transmission (heterosexual/homosexual), and other (perinatal) or unknown risk group. Subjects diagnosed before 2009 (first period) and after (second period) were analyzed separately. RESULTS: The mean age at diagnosis has increased from 22.8 years (interquartile range (IQR) = 19.5-27.2) to 29.7 years (IQR = 25.3-36.2) (p < 0.001) between the first and second periods. PWIDs were younger than other transmission groups (23.2 vs 27.1; p < 0.001). There is a statistical difference in the route of transmission among genders, with overall increasing sexual transmission. The most common AIDS-defining illness was tuberculosis (0.5%). HIV/hepatitis C (HCV) co-infection was diagnosed in 42% of cases. The population median CD4 + cell count at diagnosis has declined over the years; in total 53% have been late presenters. Half of the patients are receiving antiretroviral treatment (cART). The most common combinations are nucleoside reverse transcriptase inhibitor (NRTI) backbone plus protease inhibitors (PIs) (57%) or NRTI backbone + non-NRTIs (42%). CONCLUSION: The E-HIV enables us to fill the gap in the lack of data on the course of the new Eastern European HIV epidemic. These data demonstrate that the HIV epidemic in Estonia is moving from PWIDs to the general population, suggesting that prevention measures and testing guidelines should be revised.

Two viral strains and a possible novel recombinant are responsible for the explosive injecting drug use-associated HIV type 1 epidemic in Estonia.

HIV-1 infection has been rare in Estonia. In 2000, an explosive epidemic among injecting drug users was detected in the Eastern border region, resulting in 3603 newly reported cases by the end of 2003. The molecular epidemiology of the outbreak was studied to establish whether the Estonian epidemic is linked to the epidemics in Eastern Europe. Over 200 newly infected individuals were prospectively sampled from June 2000 to March 2002 in a geographically representative way, with known dates of diagnosis and information of probable route of transmission. Viral regions coding for two viral gene regions were directly sequenced from plasma viral RNA and phylogenetically analyzed. In addition, a larger region coding for the entire env gene was sequenced from one sample and studied for indications of possible recombinant structure. The Estonian HIV outbreak was found to be caused by simultaneous introduction of two strains: a minor subtype A strain very similar to the Eastern European subtype A strain (approximately 8% of cases), and a second major strain (77%) found to be most closely related to the CRF06-cpx strain, previously described only from African countries. The variability in the two clusters was very low, suggesting point source introductions. Ten percent of cases seemed to be newly generated recombinants of the A and CRF06-cpx strains. Analysis of viral diversification over time revealed a rate of change within the V3 region of 0.83%/year for the CRF06-cpx strain, consistent with findings from other subtypes. Due to the relatively frequently found novel recombinant forms, the Estonian HIV-1 epidemic may allow studies of coinfection and intersubtype recombination in detail.

The role of injection drug use in the emergence of Human Immunodeficiency Virus infection in Estonia.

OBJECTIVE: This article reviews the marked increase in human immunodeficiency virus (HIV) among injection drug users (IDU) in Estonia, a former Soviet Union republic bordering the Baltic Sea. HIV infection associated with injecting drug use has been reported worldwide. In Eastern Europe large-scale HIV epidemics have been observed from 1995 onward, after injection drug use (IDU) communities became infected. MATERIALS AND METHODS: In Estonia, surveillance of HIV infection is based on the mandatory universal notification of newly identified cases, with the same reporting principles in use throughout the last decades. By legal regulations every sample sent for HIV testing has to be coded (on the testing form) to identify the transmission category it belongs to. HIV testing was introduced in Estonia in 1987; by now over 2 million HIV tests have been performed. RESULTS: To date since 1987, 1305 cases of HIV have reported in Estonia. The incidence of HIV infections remained very low until recently, even when a considerable rise occurred in the incidence of sexually transmitted diseases, especially syphilis. Through 1999, only 96 cases of HIV had been reported nationally. Since then however, a dramatic increase has occurred. The cumulative data, including the information recorded on HIV testing forms and clinical records suggest that IDU was a factor in nearly 90% of the new HIV cases reported in year 2000. CONCLUSIONS: HIV infection appeared in Estonia much later than in many other parts of the world, so the experience from other countries that have confronted with the challenges of HIV could be of great help and importance for Estonia. The IDU related HIV infection epidemic in Estonia emphasizes an urgent need for preventive measures for IDUs as the target group.

Plasma HIV-1 tropism and risk of short-term clinical progression to AIDS or death.

INTRODUCTION: It is uncertain if plasma HIV-1 tropism is an independent predictor of short-term risk of clinical progression / death, in addition to the CD4 count and HIV RNA level. We conducted a nested case-control study within EuroSIDA to assess this question amongst people with current HIV RNA level >1000 copies/mL, including both people on ART and those ART naïve. METHODS: People with an AIDS diagnosis or who died from any causes for whom there was a stored plasma sample with HIV-1 RNA (VL)≥1,000 copies/mL available in the time window of 3-12 months prior to the event were identified. At least one control was selected for each case matched for age, VL and HCV status at the time of sampling. Controls were event-free after a matched duration of time from the date of sampling. Plasma HIV tropism was estimated using 454 and population sequencing (PS). Non-R5 HIV was defined as: (a) ≥2% of sequences with a Geno2Pheno (G2P) FPR≤3.75% by 454, and (b) a G2P FPR≤10% by PS. We also compared CD4 slopes over the 12 months following the date of sampling using a linear mixed model with random intercept according to HIV tropism and ART status. RESULTS: The study included 266 subjects, 100 cases and 166 controls, with sample taken on average in 2006; 23% and 24% had non-R5 HIV by 454 and PS respectively. There were 19% women, 25% MSM, 92% Caucasians, 22% HCV+. At the time of sampling, 26% were ART-naïve, 25% had started but were off ART and 49% were receiving ART. The median age, CD4 and viral load was 41 years, 350 cells/mm(3) and 4.81 log c/mL, respectively. Baseline characteristics were well balanced by tropism. Factors independently associated with clinical progression or death were female gender (OR=2.12; 95% CI=1.04, 4.36; p=0.038), CD4+ count (OR=0.90 per 100 cells/mm(3) higher; 95% CI 0.80, 1.00; p=0.058), being on ART (OR=2.72; 95% CI 1.15, 6.41; p=0.022) and calendar year of sample (OR=0.84 per more recent year; 95% CI=0.77, 0.91; p<0.001). Baseline plasma tropism was not an independent risk factor for clinical progression or death by either 454 or PS. No significant interaction was observed between tropism and ART status. There were no significant differences in the CD4+ slope within or between tropism groups. CONCLUSIONS: Plasma HIV-1 tropism does not appear to add to the ability of CD4 count and viral load to predict the short term risk of AIDS and death outcomes, even with 454 sequencing.

CD4 cell count and viral load-specific rates of AIDS, non-AIDS and deaths according to current antiretroviral use.

BACKGROUND: CD4 cell count and viral loads are used in clinical trials as surrogate endpoints for assessing efficacy of newly available antiretrovirals. If antiretrovirals act through other pathways or increase the risk of disease this would not be identified prior to licensing. The aim of this study was to investigate the CD4 cell count and viral load-specific rates of fatal and nonfatal AIDS and non-AIDS events according to current antiretrovirals. METHODS: Poisson regression was used to compare overall events (fatal or nonfatal AIDS, non-AIDS or death), AIDS events (fatal and nonfatal) or non-AIDS events (fatal or nonfatal) for specific nucleoside pairs and third drugs used with more than 1000 person-years of follow-up (PYFU) after 1 January 2001. RESULTS: Nine thousand, eight hundred and one patients contributed 42372.5 PYFU, during which 1203 (437 AIDS and 766 non-AIDS) events occurred. After adjustment, there was weak evidence of a difference in the overall events rates between nucleoside pairs (global P-value = 0.084), and third drugs (global P-value = 0.031). As compared to zidovudine/lamivudine, patients taking abacavir/lamivudine [adjusted incidence rate ratio (aIRR) 1.22; 95% CI 0.99-1.49] and abacavir and one other nucleoside [aIRR 1.51; 95% CI 1.14-2.02] had an increased incidence of overall events. Comparing the third drugs, those taking unboosted atazanavir had an increased incidence of overall events compared with those taking efavirenz (aIRR 1.46; 95% CI 1.09-1.95). CONCLUSION: There was little evidence of substantial differences between antiretrovirals in the incidence of clinical disease for a given CD4 cell count or viral load, suggesting there are unlikely to be major unidentified adverse effects of specific antiretrovirals.

Hyaluronic acid levels predict risk of hepatic encephalopathy and liver-related death in HIV/viral hepatitis coinfected patients.

BACKGROUND: Whereas it is well established that various soluble biomarkers can predict level of liver fibrosis, their ability to predict liver-related clinical outcomes is less clearly established, in particular among HIV/viral hepatitis co-infected persons. We investigated plasma hyaluronic acid's (HA) ability to predict risk of liver-related events (LRE; hepatic coma or liver-related death) in the EuroSIDA study. METHODS: Patients included were positive for anti-HCV and/or HBsAg with at least one available plasma sample. The earliest collected plasma sample was tested for HA (normal range 0-75 ng/mL) and levels were associated with risk of LRE. Change in HA per year of follow-up was estimated after measuring HA levels in latest sample before the LRE for those experiencing this outcome (cases) and in a random selection of one sixth of the remaining patients (controls). RESULTS: During a median of 8.2 years of follow-up, 84/1252 (6.7%) patients developed a LRE. Baseline median (IQR) HA in those without and with a LRE was 31.8 (17.2-62.6) and 221.6 ng/mL (74.9-611.3), respectively (p<0.0001). After adjustment, HA levels predicted risk of contracting a LRE; incidence rate ratios for HA levels 75-250 or ≥250 vs. <75 ng/mL were 5.22 (95% CI 2.86-9.26, p<0.0007) and 28.22 (95% CI 14.95-46.00, p<0.0001), respectively. Median HA levels increased substantially prior to developing a LRE (107.6 ng/mL, IQR 0.8 to 251.1), but remained stable for controls (1.0 ng/mL, IQR -5.1 to 8.2), (p<0.0001 comparing cases and controls), and greater increases predicted risk of a LRE in adjusted models (p<0.001). CONCLUSIONS: An elevated level of plasma HA, particularly if the level further increases over time, substantially increases the risk of contracting LRE over the next five years. HA is an inexpensive, standardized and non-invasive supplement to other methods aimed at identifying HIV/viral hepatitis co-infected patients at risk of hepatic complications.

Group A rotavirus genotypes circulating prior to implementation of a National Immunization Program in Estonia.

Group A rotaviruses (RVA) are a major cause of acute gastroenteritis in children ≤ 5 y worldwide which could be prevented with two recently introduced vaccines - monovalent Rotarix (live-attenuated G1P[8] strain) and pentavalent RotaTeq (human-bovine reassortant containing serotypes G1, G2, G3, G4 and P[8]). Prior to implementation of vaccines into national immunization program we aimed to describe RVA genotype distribution in hospitalized children aged < 5 y in Estonia during 2007-2008. A total of 671 children with confirmed RVA gastroenteritis from three major pediatric hospitals were prospectively enrolled. G- and P-genotypes were detected from 124 stool samples by semi-nested reverse transcription-PCR. Severity of disease was assessed using Clark scoring system. The majority of cases (65%) occurred in infants aged 7 to 24 mo and were of moderate severity (mean Clark score 12.1 (SD 3.2)). The prevailing strain was G2P[4] (34.7%), causing significantly more cases than G4P[8] (12.9%), G1P[8] or G9P[8] (both 4.0%), G3P[8] (1.6%). Yearly differences in genotype distribution occurred, as G2P[4] (52.8%) dominated in 2007, but G4P[8] (26.9%) in 2008. One third of strains remained non-typeable. The distribution of RVA genotypes in Estonia differs from that seen in other Central and Eastern European countries, although one should bear in mind the large proportion of P-untypeable strains and natural fluctuations of dominating RVA genotypes. Nevertheless, considering the high genotype-independent efficacy of the vaccines, introduction of national immunization should be considered.

Predominance of a rare type of HIV-1 in Estonia.

An earlier study has indicated that a complex recombinant HIV-1 strain dominates the epidemic in Estonia. The objective of this study was to further investigate the molecular epidemiology and genetic structure of HIV-1 in Estonia. Most of the investigated individuals became infected after August 2000 when HIV-1 started to spread rapidly among Estonian intravenous drug users (IDUs). Two viral DNA regions, gag/pol and gp41, were sequenced and subtyped from peripheral blood mononuclear cells or plasma from 141 individuals. Phylogenetic analysis in the gp41 region revealed that the most frequent type of the virus among IDUs was a circulating recombinant form, CRF06_cpx, whereas a few samples showed highest sequence similarity to a subtype A strain circulating in Ukraine and Russia. Likewise, in the gag/pol region, most of the samples were classified as CRF06_cpx, with a few classified as subtype A. In this region, however, 16% of the sequences turned out to be mosaic unique recombinant forms consisting of CRF06_cpx and subtype A. At least 9 mosaic forms were identified, each with distinct patterns of multiple crossover. To characterize Estonian CRF06_cpx as well as recombinant isolates in more detail, 4 near-full-length HIV-1 genomes were sequenced.

Sequential changes in hepatitis A virus genotype distribution in Estonia during 1994 to 2001.

Hepatitis A virus (HAV) isolates from a large outbreak and from non-outbreak cases in Estonia were characterized by sequencing the aminoterminal VP1 region. From January 1998 to December 1999, a total of 1084 cases of hepatitis A were reported to the Harjumaa-Tallinn and Ida-Virumaa Health Protection Services in Estonia. The attack rate was highest among males aged 15-29. Initial cases were noted to be associated with injecting drug use. IgM anti-HAV positive sera were available from 107 hospitalized outbreak cases and from 68 patients sampled during 1994 to 2001. HAV RNA was detected in 42% of sera from 1994-1996 and in 88% of sera from 1998-2001. It was possible to obtain HAV sequences from 83 outbreak and 29 background cases. The outbreak strain was represented by five different sequences, all belonging to subtype IIIA. During the outbreak, this IIIA strain also spread into the general population. All available non-outbreak isolates from 1994 to 2001 but one belonged to genotype IA and formed distinct clusters as compared to isolates from other parts of the world. One subtype IIIA isolate from 1995 was unrelated to the outbreak strain. Subtype IA had been dominating in Estonia during 1994-2001, but the outbreak strain from 1998 to 1999 was IIIA. This subtype was encountered previously in addicts in Sweden during the 1980s and in Norway at the end of the 1990s. This study supports the use of limited sequencing within the aminoterminal VP1 region for studying the molecular epidemiology of hepatitis A.