Treatment-limiting renal tubulopathy in patients treated with tenofovir disoproxil fumarate

OBJECTIVES

Tenofovir disoproxil fumarate (TDF) is widely used in the treatment or prevention of HIV and hepatitis B infection. TDF may cause renal tubulopathy in a small proportion of recipients. We aimed to study the risk factors for developing severe renal tubulopathy.

METHODS

We conducted an observational cohort study with retrospective identification of cases of treatment-limiting tubulopathy during TDF exposure. We used multivariate Poisson regression analysis to identify risk factors for tubulopathy, and mixed effects models to analyse adjusted estimated glomerular filtration rate (eGFR) slopes.

RESULTS

Between October 2002 and June 2013, 60 (0.4%) of 15,983 patients who had received TDF developed tubulopathy after a median exposure of 44.1 (IQR 20.4, 64.4) months. Tubulopathy cases were predominantly male (92%), of white ethnicity (93%), and exposed to antiretroviral regimens that contained boosted protease inhibitors (PI, 90%). In multivariate analysis, age, ethnicity, CD4 cell count and use of didanosine or PI were significantly associated with tubulopathy. Tubulopathy cases experienced significantly greater eGFR decline while receiving TDF than the comparator group (-6.60 [-7.70, -5.50] vs. -0.34 [-0.43, -0.26] mL/min/1.73 m²/year, p < 0.0001).

CONCLUSIONS

Older age, white ethnicity, immunodeficiency and co-administration of ddI and PI were risk factors for tubulopathy in patients who received TDF-containing antiretroviral therapy. The presence of rapid eGFR decline identified TDF recipients at increased risk of tubulopathy.

HIV-1 drug resistance mutations emerging on darunavir therapy in PI-naive and -experienced patients in the UK

BACKGROUND

Darunavir is considered to have a high genetic barrier to resistance. Most darunavir-associated drug resistance mutations (DRMs) have been identified through correlation of baseline genotype with virological response in clinical trials. However, there is little information on DRMs that are directly selected by darunavir in clinical settings.

OBJECTIVES

We examined darunavir DRMs emerging in clinical practice in the UK.

PATIENTS AND METHODS

Baseline and post-exposure protease genotypes were compared for individuals in the UK Collaborative HIV Cohort Study who had received darunavir; analyses were stratified for PI history. A selection analysis was used to compare the evolution of subtype B proteases in darunavir recipients and matched PI-naive controls.

RESULTS

Of 6918 people who had received darunavir, 386 had resistance tests pre- and post-exposure. Overall, 2.8% (11/386) of these participants developed emergent darunavir DRMs. The prevalence of baseline DRMs was 1.0% (2/198) among PI-naive participants and 13.8% (26/188) among PI-experienced participants. Emergent DRMs developed in 2.0% of the PI-naive group (4 mutations) and 3.7% of the PI-experienced group (12 mutations). Codon 77 was positively selected in the PI-naive darunavir cases, but not in the control group.

CONCLUSIONS

Our findings suggest that although emergent darunavir resistance is rare, it may be more common among PI-experienced patients than those who are PI-naive. Further investigation is required to explore whether codon 77 is a novel site involved in darunavir susceptibility.

Defining cognitive impairment in people-living-with-HIV: the POPPY study

Background

The reported prevalence of cognitive impairment (CI) varies widely in cohorts of people living with HIV (PLWH); this may partly be due to the use of different diagnostic criteria. Agreement between diagnostic criteria of CI, the optimal definition to use, and associations with patient-reported cognitive symptoms have not been fully investigated.

Methods

Two hundred ninety PLWH aged >50 years and 97 matched negative controls completed a detailed assessment of cognitive function and three questions regarding cognitive symptoms. Age- and education-adjusted test scores (T-scores) determined if subjects met the following definitions of CI: Frascati, global deficit score (GDS) and the multivariate normative comparison (MNC) method.

Results

PLWH were more likely than controls to meet each definition of CI (ORs were 2.17, 3.12 and 3.64 for Frascati, GDS and MNC, respectively). Agreement of MNC with Frascati and GDS was moderate (Cohen’s k = 0.42 and 0.48, respectively), whereas that between Frascati and GDS was good (k = 0.74). A significant association was found between all the three criteria and reporting of memory loss but not with attention and reasoning problems. The 41 (14 %) PLWH meeting all the three criteria had the lowest median global T-score (36.9) and highest rate of symptom reporting (42 %).

Conclusions

Different CI criteria show fair diagnostic agreement, likely reflecting their ability to exclude CI in the same group of individuals. Given the lower overall cognitive performance and higher rates of symptom reporting in those meeting all three criteria of CI, further work assessing this as a definition of CI in PLWH is justified.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1970-8) contains supplementary material, which is available to authorized users.

Renal Impairment and Cardiovascular Disease in HIV-Positive Individuals: The D:A:D Study

BACKGROUND

While the association between renal impairment and cardiovascular disease (CVD) is well established in the general population, the association remains poorly understood in human immunodeficiency virus (HIV)-positive individuals.

METHODS

Individuals with ≥2 estimated glomerular filtration rate (eGFR) measurements after 1 February 2004 were followed until CVD, death, last visit plus 6 months, or 1 February 2015. CVD was defined as the occurrence of centrally validated myocardial infarction, stroke, invasive cardiovascular procedures, or sudden cardiac death.

RESULTS

During a median follow-up duration of 8.0 years (interquartile range, 5.4-8.9 years) 1357 of 35 357 individuals developed CVD (incidence rate, 5.2 cases/1000 person-years [95% confidence interval {CI}, 5.0-5.5]). Confirmed baseline eGFR and CVD were closely related with 1.8% of individuals (95% CI, 1.6%-2.0%) with an eGFR > 90 mL/minute/1.73 m(2) estimated to develop CVD at 5 years, increasing to 21.1% (95% CI, 6.6%-35.6%) among those with an eGFR ≤ 30 mL/minute/1.73 m(2) The strong univariate relationship between low current eGFR and CVD was primarily explained by increasing age in adjusted analyses, although all eGFRs ≤ 80 mL/minute/1.73 m(2) remained associated with 30%-40% increased CVD rates, and particularly high CVD rates among individuals with an eGFR ≤ 30 mL/minute/1.73 m(2) (incidence rate ratio, 3.08 [95% CI, 2.04-4.65]).

CONCLUSIONS

Among HIV-positive individuals in a large contemporary cohort, a strong relation between confirmed impaired eGFR and CVD was observed. This finding highlights the need for renal preventive measures and intensified monitoring for emerging CVD, particularly in older individuals with continuously low eGFRs.

Is there continued evidence for an association between abacavir usage and myocardial infarction risk in individuals with HIV? A cohort collaboration

BACKGROUND

In March 2008, the D:A:D study published results demonstrating an increased risk of myocardial infarction (MI) for patients on abacavir (ABC). We describe changes to the use of ABC since this date, and investigate changes to the association between ABC and MI with subsequent follow-up.

METHODS

A total of 49,717 D:A:D participants were followed from study entry until the first of an MI, death, 1 February 2013 or 6 months after last visit. Associations between a person's 10-year cardiovascular disease (CVD) risk and the likelihood of initiating or discontinuing ABC were assessed using multivariable logistic/Poisson regression. Poisson regression was used to assess the association between current ABC use and MI risk, adjusting for potential confounders, and a test of interaction was performed to assess whether the association had changed in the post-March 2008 period.

RESULTS

Use of ABC increased from 10 % of the cohort in 2000 to 20 % in 2008, before stabilising at 18-19 %. Increases in use pre-March 2008, and subsequent decreases, were greatest in those at moderate and high CVD risk. Post-March 2008, those on ABC at moderate/high CVD risk were more likely to discontinue ABC than those at low/unknown CVD risk, regardless of viral load (≤1,000 copies/ml: relative rate 1.49 [95 % confidence interval 1.34-1.65]; >1,000 copies/ml: 1.23 [1.02-1.48]); no such associations were seen pre-March 2008. There was some evidence that antiretroviral therapy (ART)-naïve persons at moderate/high CVD risk post-March 2008 were less likely to initiate ABC than those at low/unknown CVD risk (odds ratio 0.74 [0.48-1.13]). By 1 February 2013, 941 MI events had occurred in 367,559 person-years. Current ABC use was associated with a 98 % increase in MI rate (RR 1.98 [1.72-2.29]) with no difference in the pre- (1.97 [1.68-2.33]) or post- (1.97 [1.43-2.72]) March 2008 periods (interaction P = 0.74).

CONCLUSIONS

Despite a reduction in the channelling of ABC for patients at higher CVD risk since 2008, we continue to observe an association between ABC use and MI risk. Whilst confounding cannot be fully ruled out, this further diminishes channelling bias as an explanation for our findings.

Antiretroviral Drugs and Risk of Chronic Alanine Aminotransferase Elevation in Human Immunodeficiency Virus (HIV)-Monoinfected Persons: The Data Collection on Adverse Events of Anti-HIV Drugs Study

Background. Although human immunodeficiency virus (HIV)-positive persons on antiretroviral therapy (ART) frequently have chronic liver enzyme elevation (cLEE), the underlying cause is often unclear.

Methods. Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) Study participants without chronic viral hepatitis were observed to the earliest of cLEE (elevated aminotransferase ≥6 months), death, last follow-up, or January 2, 2014. Antiretroviral treatment exposure was categorized as follows: no exposure and ongoing short- and long-term exposure (<2 or ≥2 years) after initiation. Association between development of cLEE and ART exposure was investigated using Poisson regression.

Results. Among 21 485 participants observed for 105 413 person-years (PY), 6368 developed cLEE (incidence 6.04/100 PY; 95% confidence interval [CI], 5.89–6.19). Chronic liver enzyme elevation was associated with short-and long-term exposure to didanosine (<2 years rate ratio [RR] = 1.29, 95% CI, 1.11–1.49; >2 years RR = 1.26, 95% CI, 1.13–1.41); stavudine (<2 years RR = 1.51, 95% CI, 1.26–1.81; >2 years RR = 1.17, 95% CI, 1.03–1.32), and tenofovir disoproxil fumarate (<2 years RR = 1.55, 95% CI, 1.40–1.72; >2 years RR = 1.18, 95% CI, 1.05–1.32), but only short-term exposure to nevirapine (<2 years RR = 1.44, 95% CI, 1.29–1.61), efavirenz (<2 years RR = 1.14, 95% CI, 1.03–1.26), emtricitabine (<2 years RR = 1.18, 95% CI, 1.04–1.33), and atazanavir (<2 years RR = 1.20, 95% CI, 1.04–1.38). Chronic liver enzyme elevation was not associated with use of lamivudine, abacavir, and other protease inhibitors. Mortality did not differ between participants with and without cLEE.

Conclusions. Although didanosine, stavudine, nevirapine, and efavirenz have been described to be hepatotoxic, we additionally observed a consistent association between tenofovir and cLEE emerging within the first 2 years after drug initiation. This novel tenofovir-cLEE signal should be further investigated.

Lopinavir and atazanavir in pregnancy: comparable infant outcomes, virological efficacies and preterm delivery rates

OBJECTIVES

The aim of the study was to identify differences in infant outcomes, virological efficacy, and preterm delivery (PTD) outcome between women exposed to lopinavir/ritonavir (LPV/r) and those exposed to atazanavir/ritonavir (ATV/r).

METHODS

A retrospective case note review was carried out. The case notes of 493 women who conceived while on LPV/r or ATV/r or initiated LPV/r or ATV/r during pregnancy and who delivered between 1 September 2007 and 30 August 2012 were reviewed. Data collected included demographics, antiretroviral use, HIV markers, and pregnancy and infant outcomes. Infant outcomes, virological efficacies and PTD rates for LPV/r and ATV/r were compared.

RESULTS

A total of 306 women received LPV/r (82 conceiving while on the drug and 224 commencing it post-conception) and 187 received ATV/r (96 conceiving while on the drug and 91 commencing it post-conception). Comparing the two protease inhibitors (PIs), viral suppression rates were similar and, in women starting antiretroviral therapy (ART) post-conception, the median times to first undetectable HIV viral load were not significantly different (P = 0.64). PTD rates did not differ by therapy overall (ATV/r, 13%; LPV/r, 14%) or when considering the timing of first exposure (conceiving on ART, P = 0.81; commencing ART in pregnancy, P = 0.08). Poor fetal outcomes were very uncommon. There were two transmissions, giving a mother-to-child transmission (MTCT) rate of 0.4% (95% confidence interval 0.05-1.5%).

CONCLUSIONS

Both ART regimens were well tolerated and successful in preventing MTCT. No significant differences in tolerability or in pregnancy or infant outcomes were observed, which supports the provision of a choice of PI in pregnancy.

Use of surveillance data on HIV diagnoses with HIV-related symptoms to estimate the number of people living with undiagnosed HIV in need of antiretroviral therapy

Background

It is important to have methods available to estimate the number of people who have undiagnosed HIV and are in need of antiretroviral therapy (ART).

Methods

The method uses the concept that a predictable level of occurrence of AIDS or other HIV-related clinical symptoms which lead to presentation for care, and hence diagnosis of HIV, arises in undiagnosed people with a given CD4 count. The method requires surveillance data on numbers of new HIV diagnoses with HIV-related symptoms, and the CD4 count at diagnosis. The CD4 count-specific rate at which HIV-related symptoms develop are estimated from cohort data. 95% confidence intervals can be constructed using a simple simulation method.

Results

For example, if there were 13 HIV diagnoses with HIV-related symptoms made in one year with CD4 count at diagnosis between 150–199 cells/mm³, then since the CD4 count-specific rate of HIV-related symptoms is estimated as 0.216 per person-year, the estimated number of person years lived in people with undiagnosed HIV with CD4 count 150–199 cells/mm3 is 13/0.216 = 60 (95% confidence interval: 29–100), which is considered an estimate of the number of people living with undiagnosed HIV in this CD4 count stratum.

Conclusions

The method is straightforward to implement within a short period once a surveillance system of all new HIV diagnoses, collecting data on HIV-related symptoms at diagnosis, is in place and is most suitable for estimating the number of undiagnosed people with CD4 count <200 cells/mm3 due to the low rate of developing HIV-related symptoms at higher CD4 counts. A potential source of bias is under-diagnosis and under-reporting of diagnoses with HIV-related symptoms. Although this method has limitations as with all approaches, it is important for prompting increased efforts to identify undiagnosed people, particularly those with low CD4 count, and for informing levels of unmet need for ART.

Hepatitis delta virus testing, epidemiology and management: a multicentre cross-sectional study of patients in London

BACKGROUND

Hepatitis delta virus (HDV) testing is recommended for all patients with hepatitis B virus (HBV) infection. HDV infection is associated with severe liver disease and interferon is the only available treatment.

OBJECTIVES

To determine the rate of anti-HDV antibody testing in HBV patients; and to describe the epidemiology, clinical characteristics and management of HDV-infected patients at four hospitals in London.

STUDY DESIGN

The anti-HDV testing rate was estimated by reviewing clinical and laboratory data. Cross-sectional data collection identified HDV-infected patients who had attended the study centres between 2005 and 2012.

RESULTS

At a centre with clinic-led anti-HDV testing, 40% (67/168) of HBV patients were tested. Recently diagnosed HBV patients were more likely to be screened than those under long-term follow-up (62% vs 36%, P=0.01). At a centre with reflex laboratory testing, 99.4% (3543/3563) of first hepatitis B surface antigen positive samples were tested for anti-HDV. Across the four study centres there were 55 HDV-infected patients, of whom 50 (91%) had immigrated to the UK and 27 (49%) had evidence of cirrhosis. 31 patients received interferon therapy for HDV with an end of treatment virological response observed in 10 (32%).

CONCLUSIONS

The anti-HDV testing rate was low in a centre with clinic-led testing, but could not be evaluated in all centres. The HDV-infected patients were of diverse ethnicity, with extensive histological evidence of liver disease and poor therapeutic responses. Future recommendations include reflex laboratory testing algorithms and a prospective cohort study to optimise the investigation and management of these patients.

Time to initiation of antiretroviral therapy in HIV-infected patients diagnosed with an opportunistic disease: a cohort study

OBJECTIVES

The aim of the study was to identify factors associated with the time between opportunistic disease (OD) diagnosis and antiretroviral therapy (ART) initiation in HIV-infected patients presenting for care with an OD, and to evaluate the outcomes associated with any delay.

METHODS

A multicentre cohort study was undertaken in London, Paris and Lille/Tourcoing. The medical records of patients diagnosed from 2002 to 2012 were reviewed.

RESULTS

A total of 437 patients were enrolled in the study: 70% were male, the median age was 40 years, 42% were from sub-Saharan Africa, 68% were heterosexual, the median CD4 count was 40 cells/μL, and the most common ODs were Pneumocystis pneumonia (37%), tuberculosis (24%), toxoplasmosis (12%) and Kaposi's sarcoma (11%). Of these patients, 400 (92%) started ART within 24 weeks after HIV diagnosis, with a median time from OD diagnosis to ART initiation of 30 [interquartile range (IQR) 16-58] days. Patients diagnosed between 2009 and 2012 had a shorter time to ART initiation than those diagnosed in earlier years [hazard ratio (HR) 2.07; 95% confidence interval (CI) 1.58-2.72]. Factors associated with a longer time to ART initiation were a CD4 count ≥ 200 cells/μL (HR 0.30; 95% CI 0.20-0.44), tuberculosis (HR 0.40; 95% CI 0.30-0.55) and diagnosis in London (HR 0.62; 95% CI 0.48-0.80). Patients initiating 'deferred' ART (by ≥ 30 days) exhibited no difference in disease progression or immunovirological response compared with patients who had shorter times to ART initiation. Patients in the 'deferred' group were less likely to have ART modifications (HR 0.69; 95% CI 0.48-1.00) and had shorter in-patient stays (mean 14.2 days shorter; 95% CI 8.9-19.5 days) than patients in the group whose ART was not deferred.

CONCLUSIONS

The time between OD diagnosis and ART initiation remains heterogeneous and relatively long, particularly in individuals with a high CD4 count or tuberculosis or those diagnosed in London. Deferring ART was associated with fewer ART modifications and shorter in-patient stays.

Trends in underlying causes of death in people with HIV from 1999 to 2011 (D:A:D): a multicohort collaboration

BACKGROUND

With the advent of effective antiretroviral treatment, the life expectancy for people with HIV is now approaching that seen in the general population. Consequently, the relative importance of other traditionally non-AIDS-related morbidities has increased. We investigated trends over time in all-cause mortality and for specific causes of death in people with HIV from 1999 to 2011.

METHODS

Individuals from the Data collection on Adverse events of anti-HIV Drugs (D:A:D) study were followed up from March, 1999, until death, loss to follow-up, or Feb 1, 2011, whichever occurred first. The D:A:D study is a collaboration of 11 cohort studies following HIV-1-positive individuals receiving care at 212 clinics in Europe, USA, and Australia. All fatal events were centrally validated at the D:A:D coordinating centre using coding causes of death in HIV (CoDe) methodology. We calculated relative rates using Poisson regression.

FINDINGS

3909 of the 49,731 D:A:D study participants died during the 308,719 person-years of follow-up (crude incidence mortality rate, 12.7 per 1000 person-years [95% CI 12.3-13.1]). Leading underlying causes were: AIDS-related (1123 [29%] deaths), non-AIDS-defining cancers (590 [15%] deaths), liver disease (515 [13%] deaths), and cardiovascular disease (436 [11%] deaths). Rates of all-cause death per 1000 person-years decreased from 17.5 in 1999-2000 to 9.1 in 2009-11; we saw similar decreases in death rates per 1000 person-years over the same period for AIDS-related deaths (5.9 to 2.0), deaths from liver disease (2.7 to 0.9), and cardiovascular disease deaths (1.8 to 0.9). However, non-AIDS cancers increased slightly from 1.6 per 1000 person-years in 1999-2000 to 2.1 in 2009-11 (p=0.58). After adjustment for factors that changed over time, including CD4 cell count, we detected no decreases in AIDS-related death rates (relative rate for 2009-11 vs 1999-2000: 0.92 [0.70-1.22]). However, all-cause (0.72 [0.61-0.83]), liver disease (0.48 [0.32-0.74]), and cardiovascular disease (0.33 [0.20-0.53) death rates still decreased over time. The percentage of all deaths that were AIDS-related (87/256 [34%] in 1999-2000 and 141/627 [22%] in 2009-11) and liver-related (40/256 [16%] in 1999-2000 and 64/627 [10%] in 2009-11) decreased over time, whereas non-AIDS cancers increased (24/256 [9%] in 1999-2000 to 142/627 [23%] in 2009-11).

INTERPRETATION

Recent reductions in rates of AIDS-related deaths are linked with continued improvement in CD4 cell count. We hypothesise that the substantially reduced rates of liver disease and cardiovascular disease deaths over time could be explained by improved use of non-HIV-specific preventive interventions. Non-AIDS cancer is now the leading non-AIDS cause and without any evidence of improvement.

FUNDING

Oversight Committee for the Evaluation of Metabolic Complications of HAART, with representatives from academia, patient community, US Food and Drug Administration, European Medicines Agency and consortium of AbbVie, Boehringer Ingelheim, Bristol-Myers Squibb, Gilead Sciences, ViiV Healthcare, Merck, Pfizer, F Hoffmann-La Roche, and Janssen Pharmaceuticals.

Increased risk of cardiovascular disease (CVD) with age in HIV-positive men: a comparison of the D:A:D CVD risk equation and general population CVD risk equations

OBJECTIVES

The aim of the study was to statistically model the relative increased risk of cardiovascular disease (CVD) per year older in Data collection on Adverse events of anti-HIV Drugs (D:A:D) and to compare this with the relative increased risk of CVD per year older in general population risk equations.

METHODS

We analysed three endpoints: myocardial infarction (MI), coronary heart disease (CHD: MI or invasive coronary procedure) and CVD (CHD or stroke). We fitted a number of parametric age effects, adjusting for known risk factors and antiretroviral therapy (ART) use. The best-fitting age effect was determined using the Akaike information criterion. We compared the ageing effect from D:A:D with that from the general population risk equations: the Framingham Heart Study, CUORE and ASSIGN risk scores.

RESULTS

A total of 24 323 men were included in analyses. Crude MI, CHD and CVD event rates per 1000 person-years increased from 2.29, 3.11 and 3.65 in those aged 40-45 years to 6.53, 11.91 and 15.89 in those aged 60-65 years, respectively. The best-fitting models included inverse age for MI and age + age(2) for CHD and CVD. In D:A:D there was a slowly accelerating increased risk of CHD and CVD per year older, which appeared to be only modest yet was consistently raised compared with the risk in the general population. The relative risk of MI with age was not different between D:A:D and the general population.

CONCLUSIONS

We found only limited evidence of accelerating increased risk of CVD with age in D:A:D compared with the general population. The absolute risk of CVD associated with HIV infection remains uncertain.

Incomplete reversibility of estimated glomerular filtration rate decline following tenofovir disoproxil fumarate exposure

Background. Tenofovir disoproxil fumarate (TDF) has been linked to renal impairment, but the extent to which this impairment is reversible is unclear. We aimed to investigate the reversibility of renal decline during TDF therapy.

Methods. Cox proportional hazards models assessed factors associated with discontinuing TDF in those with an exposure duration of >6 months. In those who discontinued TDF therapy, linear piecewise regression models estimated glomerular filtration rate (eGFR) slopes before initiation of, during, and after discontinuation of TDF therapy. Factors associated with not achieving eGFR recovery 6 months after discontinuing TDF were assessed using multivariable logistic regression.

Results. We observed declines in the eGFR during TDF exposure (mean slopes, −15.7 mL/minute/1.73 m²/year [95% confidence interval {CI}, −20.5 to −10.9] during the first 3 months and −3.1 mL/minute/1.73 m²/year [95% CI, −4.6 to −1.7] thereafter) and evidence of eGFR increases following discontinuation of TDF therapy (mean slopes, 12.5 mL/minute/1.73 m²/year [95% CI, 8.9–16.1] during the first 3 months and 0.8 mL/minute/1.73 m²/year [95% CI, .1–1.5] thereafter). Following TDF discontinuation, 38.6% of patients with a decline in the eGFR did not experience recovery. A higher eGFR at baseline, a lower eGFR after discontinuation of TDF therapy, and more-prolonged exposure to TDF were associated with an increased risk of incomplete recovery 6 months after discontinuation of TDF therapy.

Conclusions. This study shows that a decline in the eGFR during TDF therapy was not fully reversible in one third of patients and suggests that prolonged TDF exposure at a low eGFR should be avoided.

The Effect of HBV Genotype C on the Development of HCC Differs Between Wild-Type Viruses and Those With BCP Double Mutations (T(1762)A(1764))

BACKGROUND

Association of hepatitis B virus (HBV) genotype C with hepatocellular carcinoma (HCC) development remains controversial. HBV basal core promoter (BCP) double mutations (T(1762)A(1764)) are very strong confounding factors of genotypes B and C in HCC development.

OBJECTIVES

To investigate the association of HBV genotype C with HCC development after controlling for BCP double mutations.

MATERIALS AND METHODS

Four hundred and two serum samples from patients with HCC, liver cirrhosis (LC) and chronic hepatitis (CH) and also from asymptomatic HBsAg carriers were analyzed.

RESULTS

Genotypes B (31.1%), C (62.8%), and I (6.1%) were detected. With the severity of liver disease the prevalence of genotype B decreased, but genotype C increased. No trend was found for genotype I. The prevalence of BCP double mutations in genotypes C and I viruses was significantly higher than genotype B. BCP double mutations are risk factors for CH, LC and HCC. Genotype C was not identified as a particular risk factor for HCC prior to the stratification analysis but after that genotype C viruses with BCP double mutations were found to be a particular risk factor for HCC (P = 0.008, OR = 17.19 [95% CI: 2.10 - 140.41]), but those with the wild-type BCP were not. In the interaction analysis, genotype C and BCP double mutations were found to have a synergistic effect on HCC development (P < 0.0001, OR = 52.56 [95% CI: 11.49-240.52]).

CONCLUSIONS

The effect of HBV genotype C on the development of HCC differs between wild-type viruses and those with BCP double mutations, suggesting that not all individuals infected with genotype C HBV are at increased risk of HCC.

Do people with HIV infection have a normal life expectancy in the era of combination antiretroviral therapy?

There is evidence that the life expectancy (LE) of individuals infected with the human immunodeficiency virus (HIV) has increased since the introduction of combination antiretroviral therapy (cART). However, mortality rates in recent years in HIV-positive individuals appear to have remained higher than would be expected based on rates seen in the general population. A low CD4 count, whether due to late HIV diagnosis, late initiation of cART, or incomplete adherence to cART, remains the dominant predictor of LE, and thus the individual's disease stage at initiation of cART (or thereafter) certainly contributes to these higher mortality rates. However, individuals with HIV also tend to exhibit lifestyles and behaviors that place them at increased risk of mortality, particularly from non-AIDS causes. Thus, although mortality rates among the HIV population may indeed remain slightly higher than those seen in the general population, they may be no higher than those seen in a more appropriately matched control group. Thus, further improvements in LE may now only be possible if some of the other underlying issues (for example, modification of lifestyle or behavioral factors) are tackled.

The effects of age on associations between markers of HIV progression and markers of metabolic function including albumin, haemoglobin and lipid concentrations

OBJECTIVES

We investigated whether age modified associations between markers of HIV progression, CD4 T lymphocyte count and HIV RNA viral load (VL), and the following markers of metabolic function: albumin, haemoglobin, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC).

METHODS

A retrospective analysis of data from the United Kingdom Collaborative HIV Cohort was carried out. Analyses were limited to antiretroviral-naïve subjects to focus on the impact of HIV disease itself. A total of 16670 subjects were included in the analysis. Multilevel linear regression models assessed associations between CD4 count/VL and each of the outcomes. Statistical tests for interactions assessed whether associations differed among age groups.

RESULTS

After adjustment for gender and ethnicity, there was evidence that lower CD4 count and higher VL were associated with lower TC, LDL-C, haemoglobin and albumin concentrations but higher triglyceride concentrations. Age modified associations between CD4 count and albumin (P < 0.001) and haemoglobin (P = 0.001), but not between CD4 count and HDL-C, LDL-C and TC, or VL and any outcome. Among participants aged < 30, 30-50 and > 50 years, a 50 cells/μL lower CD4 count correlated with a 2.4 [95% confidence interval (CI) 1.7-3.0], 3.6 (95% CI 3.2-4.0) and 5.1 (95% CI 4.0-6.1) g/L lower haemoglobin concentration and a 0.09 (95% CI 0.07-0.11), 0.12 (95% CI 0.11-0.13) and 0.16 (95% CI 0.13-0.19) g/L lower albumin concentration, respectively.

CONCLUSIONS

We present evidence that age modifies associations between CD4 count and plasma albumin and haemoglobin levels. A given reduction in CD4 count was associated with a greater reduction in haemoglobin and albumin concentrations among older people living with HIV. These findings increase our understanding of how the metabolic impact of HIV is influenced by age.

Non-AIDS defining cancers in the D:A:D Study--time trends and predictors of survival: a cohort study

Background

Non-AIDS defining cancers (NADC) are an important cause of morbidity and mortality in HIV-positive individuals. Using data from a large international cohort of HIV-positive individuals, we described the incidence of NADC from 2004–2010, and described subsequent mortality and predictors of these.

Methods

Individuals were followed from 1st January 2004/enrolment in study, until the earliest of a new NADC, 1st February 2010, death or six months after the patient’s last visit. Incidence rates were estimated for each year of follow-up, overall and stratified by gender, age and mode of HIV acquisition. Cumulative risk of mortality following NADC diagnosis was summarised using Kaplan-Meier methods, with follow-up for these analyses from the date of NADC diagnosis until the patient’s death, 1st February 2010 or 6 months after the patient’s last visit. Factors associated with mortality following NADC diagnosis were identified using multivariable Cox proportional hazards regression.

Results

Over 176,775 person-years (PY), 880 (2.1%) patients developed a new NADC (incidence: 4.98/1000PY [95% confidence interval 4.65, 5.31]). Over a third of these patients (327, 37.2%) had died by 1st February 2010. Time trends for lung cancer, anal cancer and Hodgkin’s lymphoma were broadly consistent. Kaplan-Meier cumulative mortality estimates at 1, 3 and 5 years after NADC diagnosis were 28.2% [95% CI 25.1-31.2], 42.0% [38.2-45.8] and 47.3% [42.4-52.2], respectively. Significant predictors of poorer survival after diagnosis of NADC were lung cancer (compared to other cancer types), male gender, non-white ethnicity, and smoking status. Later year of diagnosis and higher CD4 count at NADC diagnosis were associated with improved survival. The incidence of NADC remained stable over the period 2004–2010 in this large observational cohort.

Conclusions

The prognosis after diagnosis of NADC, in particular lung cancer and disseminated cancer, is poor but has improved somewhat over time. Modifiable risk factors, such as smoking and low CD4 counts, were associated with mortality following a diagnosis of NADC.

Low frequency of genotypic resistance in HIV-1-infected patients failing an atazanavir-containing regimen: a clinical cohort study

OBJECTIVES

To determine protease mutations that develop at viral failure for protease inhibitor (PI)-naive patients on a regimen containing the PI atazanavir.

METHODS

Resistance tests on patients failing atazanavir, conducted as part of routine clinical care in a multicentre observational study, were randomly matched by subtype to resistance tests from PI-naive controls to account for natural polymorphisms. Mutations from the consensus B sequence across the protease region were analysed for association and defined using the IAS-USA 2011 classification list.

RESULTS

Four hundred and five of 2528 (16%) patients failed therapy containing atazanavir as a first PI over a median (IQR) follow-up of 1.76 (0.84-3.15) years and 322 resistance tests were available for analysis. Recognized major atazanavir mutations were found in six atazanavir-experienced patients (P < 0.001), including I50L and N88S. The minor mutations most strongly associated with atazanavir experience were M36I, M46I, F53L, A71V, V82T and I85V (P < 0.05). Multiple novel mutations, I15S, L19T, K43T, L63P/V, K70Q, V77I and L89I/T/V, were also associated with atazanavir experience.

CONCLUSIONS

Viral failure on atazanavir-containing regimens was not common and major resistance mutations were rare, suggesting that adherence may be a major contributor to viral failure. Novel mutations were described that have not been previously documented.

Impact of switching from zidovudine to tenofovir disoproxil fumarate on bone mineral density and markers of bone metabolism in virologically suppressed HIV-1 infected patients; a substudy of the PREPARE study

CONTEXT

In virologically suppressed, antiretroviral-treated patients, the effect of switching to tenofovir (TDF) on bone biomarkers compared to patients remaining on stable antiretroviral therapy is unknown.

METHODS

We examined bone biomarkers (osteocalcin [OC], procollagen type 1 amino-terminal propeptide, and C-terminal cross-linking telopeptide of type 1 collagen) and bone mineral density (BMD) over 48 weeks in virologically suppressed patients (HIV RNA < 50 copies/ml) randomized to switch to TDF/emtricitabine (FTC) or remain on first-line zidovudine (AZT)/lamivudine (3TC). PTH was also measured. Between-group differences in bone biomarkers and associations between change in bone biomarkers and BMD measures were assessed by Student's t tests, Pearson correlation, and multivariable linear regression, respectively. All data are expressed as mean (SD), unless otherwise specified.

RESULTS

Of 53 subjects (aged 46.0 y; 84.9% male; 75.5% Caucasian), 29 switched to TDF/FTC. There were reductions in total hip and lumbar spine BMD in those switching to TDF/FTC (total hip, TDF/FTC, -1.73 (2.76)% vs AZT/3TC, -0.39 (2.41)%; between-group P = .07; lumbar spine, TDF/FTC, -1.50 (3.49)% vs AZT/3TC, +0.25 (2.82)%; between-group P = .06), but they did not reach statistical significance. Greater declines in lumbar spine BMD correlated with greater increases in OC (r = -0.28; P = .05). The effect of TDF/FTC on bone biomarkers remained significant when adjusted for baseline biomarker levels, gender, and ethnicity. There was no difference in change in PTH levels over 48 weeks between treatment groups (between-group P = .23). All biomarkers increased significantly from weeks 0 to 48 in the switch group, with no significant change in those remaining on AZT/3TC (between-group, all biomarkers, P < .0001).

CONCLUSION

A switch to TDF/FTC compared to remaining on a stable regimen is associated with increases in bone turnover that correlate with reductions in BMD, suggesting that TDF exposure directly affects bone metabolism in vivo.

Predictors of pregnancy and changes in pregnancy incidence among HIV-positive women accessing HIV clinical care

OBJECTIVES

To describe predictors of pregnancy and changes in pregnancy incidence among HIV-positive women accessing HIV clinical care.

METHODS

Data were obtained through the linkage of two separate studies: the UK Collaborative HIV Cohort study (UK CHIC), a cohort of adults attending 13 large HIV clinics; and the National Study of HIV in Pregnancy and Childhood (NSHPC), a national surveillance study of HIV-positive pregnant women. Pregnancy incidence was measured using the proportion of women in UK CHIC with a pregnancy reported to NSHPC. Generalized estimating equations were used to identify predictors of pregnancy and assess changes in pregnancy incidence in 2000-2009.

RESULTS

The number of women accessing care at UK CHIC sites increased as did the number of pregnancies. Older women were less likely to have a pregnancy [adjusted relative rate (aRR) 0.44 per 10 year increment in age, [95% confidence interval (CI) (0.41-0.46)], P < 0.001] as were women with CD4 cell count less than 200 cells/μl compared with CD4 cell count 200-350 cells/μl [aRR 0.65 (0.55-0.77), P < 0.001] and women of white ethnicity compared with women of black African ethnicity [aRR 0.67 (0.57-0.80), P < 0.001]. The likelihood that women had a pregnancy increased over the study period [aRR 1.05 (1.03-1.07), P < 0.001). The rate of change did not significantly differ according to age group, antiretroviral therapy use, CD4 group or ethnicity.

CONCLUSION

The pregnancy rate among women accessing HIV clinical care increased in 2000-2009. HIV-positive women with, or planning, a pregnancy require a high level of care and this is likely to continue and increase as more women of older age have pregnancies.

Antiretroviral drug-related liver mortality among HIV-positive persons in the absence of hepatitis B or C virus coinfection: the data collection on adverse events of anti-HIV drugs study

BACKGROUND

Liver diseases are the leading causes of death in human immunodeficiency virus (HIV)-positive persons since the widespread use of combination antiretroviral treatment (cART). Most of these deaths are due to hepatitis C (HCV) or B (HBV) virus coinfections. Little is known about other causes. Prolonged exposure to some antiretroviral drugs might increase hepatic mortality.

METHODS

All patients in the Data Collection on Adverse Events of Anti-HIV Drugs study without HCV or HBV coinfection were prospectively followed from date of entry until death or last follow-up. In patients with liver-related death, clinical charts were reviewed using a structured questionnaire.

RESULTS

We followed 22 910 participants without hepatitis virus coinfection for 114 478 person-years. There were 12 liver-related deaths (incidence, 0.10/1000 person-years); 7 due to severe alcohol use and 5 due to established ART-related toxicity. The rate of ART-related deaths in treatment-experienced persons was 0.04/1000 person-years (95% confidence interval, .01, .10).

CONCLUSIONS

We found a low incidence of liver-related deaths in HIV-infected persons without HCV or HBV coinfection. Liver-related mortality because of ART-related toxicity was rare.

Using two on-going HIV studies to obtain clinical data from before, during and after pregnancy for HIV-positive women

Background

The UK Collaborative HIV Cohort (UK CHIC) is an observational study that collates data on HIV-positive adults accessing HIV clinical care at (currently) 13 large clinics in the UK but does not collect pregnancy specific data. The National Study of HIV in Pregnancy and Childhood (NSHPC) collates data on HIV-positive women receiving antenatal care from every maternity unit in the UK and Ireland. Both studies collate pseudonymised data and neither dataset contains unique patient identifiers. A methodology was developed to find and match records for women reported to both studies thereby obtaining clinical and treatment data on pregnant HIV-positive women not available from either dataset alone.

Results

Women in UK CHIC receiving HIV-clinical care in 1996–2009, were found in the NSHPC dataset by initially ‘linking’ records with identical date-of-birth, linked records were then accepted as a genuine ‘match’, if they had further matching fields including CD4 test date. In total, 2063 women were found in both datasets, representing 23.1% of HIV-positive women with a pregnancy in the UK (n = 8932). Clinical data was available in UK CHIC following most pregnancies (92.0%, 2471/2685 pregnancies starting before 2009). There was bias towards matching women with repeat pregnancies (35.9% (741/2063) of women found in both datasets had a repeat pregnancy compared to 21.9% (1502/6869) of women in NSHPC only) and matching women HIV diagnosed before their first reported pregnancy (54.8% (1131/2063) compared to 47.7% (3278/6869), respectively).

Conclusions

Through the use of demographic data and clinical dates, records from two independent studies were successfully matched, providing data not available from either study alone.