Think TB! Is the diagnosis of pulmonary tuberculosis delayed by the use of antibiotics?

SETTING

Effective tuberculosis (TB) control requires prompt diagnosis of infectious cases through early suspicion of pulmonary TB in all subjects with suspected respiratory infection.

OBJECTIVE

To test our hypothesis that prior antibiotic treatment for presumed bacterial infection leads to a delay in diagnosing TB in a European country with low TB incidence.

DESIGN

Adults with culture-confirmed pulmonary TB at a single metropolitan centre were assessed for the impact of any previous antibiotic treatment on symptoms and the time to starting specific anti-tuberculosis treatment.

RESULTS

Of 83 patients, 42 (51%) received antibiotics prior to TB diagnosis, with symptomatic improvement reported in 20 of the 42 (48%) patients. This was unrelated to specific drug class. Although the median time to diagnosis in subjects receiving antibiotics was prolonged (P=0.001), this was not predicted by treatment response. In 94% of cases, the initial chest radiograph was suggestive of TB infection.

CONCLUSION

Patients receiving antibiotics prior to TB confirmation experience a process-related delay in starting treatment. To minimise the risk of ongoing TB transmission, we propose that clinicians should include TB in their differential diagnosis and initiate simple, TB-focused investigations early on in the diagnostic process.

Hepatitis B virus pre-S deletion mutations are a risk factor for hepatocellular carcinoma: a matched nested case-control study

A matched nested case-control study of 33 paired cases and controls was conducted, based on a study cohort in Long An county, Guangxi, China, to determine whether infection with hepatitis B virus (HBV) with pre-S deletions is independently associated with the development of hepatocellular carcinoma (HCC), without the confounding effects of basal core promoter (BCP) double mutations. The prevalence of pre-S deletions was significantly higher in HCC (45.5 %, 15 of 33) than the controls (18.2 %, 6 of 33) (P<0.01), under the control of the influence of BCP double mutations. Most of the pre-S deletions occurred in, or involved, the 5' half of the pre-S2 region and the difference between HCC (93.3 %, 14 of 15) and controls (66.7 %, four of six) was significant for this region (P=0.015). There was no significant difference in pre-S deletions between the BCP mutant group and BCP wild-type group (P>0.05), nor was the prevalence of pre-S deletions significantly different between genotypes B and C (P>0.1). These results suggest that pre-S deletions constitute an independent risk factor for HCC and their emergence and effect are independent of BCP mutations. The 5' terminus of pre-S2 is the favoured site for the deletion mutations, especially in HCC cases. Further prospective studies are required to confirm the role of these mutations in the development of HCC.

The associations between age and the development of laboratory abnormalities and treatment discontinuation for reasons other than virological failure in the first year of highly active antiretroviral therapy

OBJECTIVE

The aim of this study was to describe the relationship between age and the time to treatment discontinuation in the absence of virological failure as well as the development of specific laboratory abnormalities, in patients starting highly active antiretroviral therapy (HAART) for the first time.

METHODS

Analyses included 8708 antiretroviral-naïve patients from the UK Collaborative HIV Cohort (CHIC) study who started HAART from 1998 onwards. We considered time to the first discontinuation of any drug in the initial HAART regimen for reasons other than virological failure; the association between this and age at the start of HAART was determined using proportional hazards regression after adjustment for potential confounders. The incidence of specific laboratory abnormalities in the first year after starting HAART was compared in those of different ages using multiple logistic regression.

RESULTS

A total of 2650 patients discontinued at least one drug in their HAART regimen in the first year for reasons other than virological failure; after controlling for confounders, those aged < 30 years at the time of starting HAART were more likely to discontinue than those aged 30-39 years [relative hazard (RH) 1.12; 95% confidence interval (CI) 1.01, 1.24] as were those aged > or = 50 years (RH 1.14; 95% CI 1.00, 1.31). There were strong associations between greater age and raised total cholesterol, decreased haemoglobin and raised triglycerides over the first year, although the latter disappeared after adjustment for pre-HAART levels, suggesting that this finding reflected higher pre-HAART triglyceride levels in older individuals.

CONCLUSIONS

Continued attempts to improve the tolerability of HAART regimens may help to sustain the good outcomes in all age groups over the longer term.

Prognostic Importance of Anaemia in HIV Type-1-Infected Patients Starting Antiretroviral Therapy: Collaborative Analysis of Prospective Cohort Studies

Background

In HIV type-1-infected patients starting highly active antiretroviral therapy (HAART), the prognostic value of haemoglobin when starting HAART, and of changes in haemoglobin levels, are not well defined.

Methods

We combined data from 10 prospective studies of 12,100 previously untreated individuals (25% women). A total of 4,222 patients (35%) were anaemic: 131 patients (1.1%) had severe (<8.0 g/dl), 1,120 (9%) had moderate (male 8.0–<11.0 g/dl and female 8.0–<10.0 g/ dl) and 2,971 (25%) had mild (male 11.0–<13.0 g/dl and female 10.0–<12.0 g/dl) anaemia. We separately analysed progression to AIDS or death from baseline and from 6 months using Weibull models, adjusting for CD4+ T-cell count, age, sex and other variables.

Results

During 48,420 person-years of follow-up 1,448 patients developed at least one AIDS event and 857 patients died. Anaemia at baseline was independently associated with higher mortality: the adjusted hazard ratio (95% confidence interval) for mild anaemia was 1.42 (1.17–1.73), for moderate anaemia 2.56 (2.07–3.18) and for severe anaemia 5.26 (3.55–7.81). Corresponding figures for progression to AIDS were 1.60 (1.37–1.86), 2.00 (1.66–2.40) and 2.24 (1.46–3.42). At 6 months the prevalence of anaemia declined to 26%. Baseline anaemia continued to predict mortality (and to a lesser extent progression to AIDS) in patients with normal haemoglobin or mild anaemia at 6 months.

Conclusions

Anaemia at the start of HAART is an important factor for short- and long-term prognosis, including in patients whose haemoglobin levels improved or normalized during the first 6 months of HAART.

HIV-induced immunodeficiency and mortality from AIDS-defining and non-AIDS-defining malignancies

OBJECTIVE

To evaluate deaths from AIDS-defining malignancies (ADM) and non-AIDS-defining malignancies (nADM) in the D:A:D Study and to investigate the relationship between these deaths and immunodeficiency.

DESIGN

Observational cohort study.

METHODS

Patients (23 437) were followed prospectively for 104 921 person-years. We used Poisson regression models to identify factors independently associated with deaths from ADM and nADM. Analyses of factors associated with mortality due to nADM were repeated after excluding nADM known to be associated with a specific risk factor.

RESULTS

Three hundred five patients died due to a malignancy, 298 prior to the cutoff for this analysis (ADM: n = 110; nADM: n = 188). The mortality rate due to ADM decreased from 20.1/1000 person-years of follow-up [95% confidence interval (CI) 14.4, 25.9] when the most recent CD4 cell count was <50 cells/microl to 0.1 (0.03, 0.3)/1000 person-years of follow-up when the CD4 cell count was more than 500 cells/microl; the mortality rate from nADM decreased from 6.0 (95% CI 3.3, 10.1) to 0.6 (0.4, 0.8) per 1000 person-years of follow-up between these two CD4 cell count strata. In multivariable regression analyses, a two-fold higher latest CD4 cell count was associated with a halving of the risk of ADM mortality. Other predictors of an increased risk of ADM mortality were homosexual risk group, older age, a previous (non-malignancy) AIDS diagnosis and earlier calendar years. Predictors of an increased risk of nADM mortality included lower CD4 cell count, older age, current/ex-smoking status, longer cumulative exposure to combination antiretroviral therapy, active hepatitis B infection and earlier calendar year.

CONCLUSION

The severity of immunosuppression is predictive of death from both ADM and nADM in HIV-infected populations.

Impact of HIV on host-virus interactions during early hepatitis C virus infection

BACKGROUND

Human immunodeficiency virus (HIV) may influence the outcome and natural history of hepatitis C virus (HCV) infection through an impact on acute HCV-specific T cell responses.

METHODS

Fifty-five HIV-positive males with acute HCV infection were identified; monoinfected individuals (n = 8) were used for peripheral blood mononuclear cell comparison. In 14 coinfected and 8 HCV-monoinfected patients, HCV-specific T cell responses against a range of HCV antigens were assessed using interferon (IFN)-gamma enzyme-linked immunospot (ELISpot) and proliferation assays. E1/E2 region genetic diversity and the selection pressure on the virus were measured in 8 coinfected patients by use of cloned sequences over time.

RESULTS

HCV persisted in 52 (95%) coinfected individuals. HCV/HIV coinfection significantly reduced IFN-gamma ELISpot responses versus those in HCV-monoinfected individuals, especially against nonstructural proteins (1/10 vs. 5/8; P = .008). In coinfected patients, increased HCV genetic diversity was observed between the first and subsequent time points, with no evidence for positive selection in the E1/E2 region sequenced.

CONCLUSION

HIV coinfection is associated with increased rates of HCV persistence and a lack of critical CD4 T cell responses, with no evidence of immune selection pressure during early HCV infection. Loss of key cellular immune responses against HCV during acute disease may contribute to the failure of early host control of HCV in HCV/HIV-coinfected patients.

HBV A1762T, G1764A mutations are a valuable biomarker for identifying a subset of male HBsAg carriers at extremely high risk of hepatocellular carcinoma: a prospective study

OBJECTIVES

Surveillance of hepatocellular carcinoma (HCC) can detect small tumors for resection but at a huge cost of health resources. The challenge is to reduce the surveillance population. We reported that 96% of HCC patients but only 24% of controls were infected with the hepatitis B virus (HBV) with A(1762)T, G(1764)A mutations in Guangxi, China. It is likely to be extremely beneficial in terms of cost and resources if a significant number of tumors can be detected early by screening this selected population. Our aim is to test this hypothesis.

METHODS

A cohort of 2,258 hepatitis B surface antigen-positive subjects aged 30-55 yr was recruited in Guangxi. Following evaluation of virological parameters at baseline, HCC is diagnosed by 6-monthly measurements of serum alpha-fetoprotein levels and ultrasonographic examinations.

RESULTS

Sixty-one cases of HCC were diagnosed after 36 months of follow-up. The HCC rate was higher in the mutant than wild-type group (P < 0.001, rate ratio [RR] 6.23, 95% confidence interval [CI] 2.83-13.68). The HCC rate in the male mutant group was higher than that in the male wild-type group (P < 0.001, RR 11.54, 95% CI 3.58-37.24). Specifically, 93.3% of male cases are infected with the mutant. Multivariate analyses showed that in men, increasing age and A(1762)T, G(1764)A double mutations are independently associated with developing HCC.

CONCLUSIONS

HBV A(1762)T, G(1764)A mutations constitute a valuable biomarker to identify a subset of male HBsAg carriers aged >30 yr at extremely high risk of HCC in Guangxi, and likely elsewhere.

Patterns and predictors of the use of different antiretroviral drug regimens at treatment initiation in the UK

BACKGROUND

We describe the patterns of antiretroviral drug use at treatment initiation from 1996 to 2005 in a large UK multicentre cohort.

METHODS

We examined trends over time and across 10 clinical sites in stage of disease and type of antiretroviral therapy (ART). Multivariable regression was used to identify factors associated with the CD4 cell count at ART initiation, and with the choice of a protease inhibitor (PI) over a nonnucleoside reverse transcriptase inhibitor (NNRTI), and use of nevirapine over efavirenz.

RESULTS

A total of 14 252 patients initiated ART, of whom 54% had a CD4 count <200 cells/microL. The most important predictors of starting ART at a lower CD4 cell count were being male, nonwhite, and heterosexual or an injecting drug user (P<0.0001). Among those starting ART, the use of highly active ART increased from 23% in 1996 to >96% from 2000 onwards. There were differences over time and across the clinics in the use of PIs vs. NNRTIs, in the choice of specific PIs, NNRTIs and nucleoside reverse transcriptase inhibitor (NRTI) backbone, and in the rate at which prescribing practices changed.

CONCLUSIONS

Clinic site and calendar year were important determinants of choice of drug at ART initiation, whereas clinical and demographic characteristics were more important in influencing the CD4 cell count at initiation of ART.

Changes over time in risk factors for cardiovascular disease and use of lipid-lowering drugs in HIV-infected individuals and impact on myocardial infarction

BACKGROUND

Because of the known relationship between exposure to combination antiretroviral therapy and cardiovascular disease (CVD), it has become increasingly important to intervene against risk of CVD in human immunodeficiency virus (HIV)-infected patients. We evaluated changes in risk factors for CVD and the use of lipid-lowering therapy in HIV-infected individuals and assessed the impact of any changes on the incidence of myocardial infarction.

METHODS

The Data Collection on Adverse Events of Anti-HIV Drugs Study is a collaboration of 11 cohorts of HIV-infected patients that included follow-up for 33,389 HIV-infected patients from December 1999 through February 2006.

RESULTS

The proportion of patients at high risk of CVD increased from 35.3% during 1999-2000 to 41.3% during 2005-2006. Of 28,985 patients, 2801 (9.7%) initiated lipid-lowering therapy; initiation of lipid-lowering therapy was more common for those with abnormal lipid values and those with traditional risk factors for CVD (male sex, older age, higher body mass index [calculated as the weight in kilograms divided by the square of the height in meters], family and personal history of CVD, and diabetes mellitus). After controlling for these, use of lipid-lowering drugs became relatively less common over time. The incidence of myocardial infarction (0.32 cases per 100 person-years [PY]; 95% confidence interval [CI], 0.29-0.35 cases per 100 PY) appeared to remain stable. However, after controlling for changes in risk factors for CVD, the rate decreased over time (relative rate in 2003 [compared with 1999-2000], 0.73 cases per 100 PY [95% CI, 0.50-1.05 cases per 100 PY]; in 2004, 0.64 cases per 100 PY [95% CI, 0.44-0.94 cases per 100 PY]; in 2005-2006, 0.36 cases per 100 PY [95% CI, 0.24-0.56 cases per 100 PY]). Further adjustment for lipid levels attenuated the relative rates towards unity (relative rate in 2003 [compared with 1999-2000], 1.06 cases per 100 PY [95% CI, 0.63-1.77 cases per 100 PY]; in 2004, 1.02 cases per 100 PY [95% CI, 0.61-1.71 cases per 100 PY]; in 2005-2006, 0.63 cases per 100 PY [95% CI, 0.36-1.09 cases per 100 PY]).

CONCLUSIONS

Although the CVD risk profile among patients in the Data Collection on Adverse Events of Anti-HIV Drugs Study has decreased since 1999, rates have remained relatively stable, possibly as a result of a more aggressive approach towards managing the risk of CVD.

Incidence and risk factors for new-onset diabetes in HIV-infected patients: the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) study

OBJECTIVE

The aims of this study were to determine the incidence of diabetes among HIV-infected patients in the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) cohort, to identify demographic, HIV-related, and combination antiretroviral therapy (cART)-related factors associated with the onset of diabetes, and to identify possible mechanisms for any relationships found.

RESEARCH DESIGN AND METHODS

D:A:D is a prospective observational study of 33,389 HIV-infected patients; diabetes is a study end point. Poisson regression models were used to assess the relation between diabetes and exposure to cART after adjusting for known risk factors for diabetes, CD4 count, lipids, and lipodystrophy.

RESULTS

Over 130,151 person-years of follow-up (PYFU), diabetes was diagnosed in 744 patients (incidence rate of 5.72 per 1,000 PYFU [95% CI 5.31-6.13]). The incidence of diabetes increased with cumulative exposure to cART, an association that remained significant after adjustment for potential risk factors for diabetes. The strongest relationship with diabetes was exposure to stavudine; exposures to zidovudine and didanosine were also associated with an increased risk of diabetes. Time-updated measurements of total cholesterol, HDL cholesterol, and triglycerides were all associated with diabetes. Adjusting for each of these variables separately reduced the relationship between cART and diabetes slightly. Although lipodystrophy was significantly associated with diabetes, adjustment for this did not modify the relationship between cART and diabetes.

CONCLUSION

Stavudine and zidovudine are significantly associated with diabetes after adjustment for risk factors for diabetes and lipids. Adjustment for lipodystrophy did not modify the relationship, suggesting that the two thymidine analogs probably directly contribute to insulin resistance, potentially through mitochondrial toxicity.

Use of nucleoside reverse transcriptase inhibitors and risk of myocardial infarction in HIV-infected patients enrolled in the D:A:D study: a multi-cohort collaboration

BACKGROUND

Whether nucleoside reverse transcriptase inhibitors increase the risk of myocardial infarction in HIV-infected individuals is unclear. Our aim was to explore whether exposure to such drugs was associated with an excess risk of myocardial infarction in a large, prospective observational cohort of HIV-infected patients.

METHODS

We used Poisson regression models to quantify the relation between cumulative, recent (currently or within the preceding 6 months), and past use of zidovudine, didanosine, stavudine, lamivudine, and abacavir and development of myocardial infarction in 33 347 patients enrolled in the D:A:D study. We adjusted for cardiovascular risk factors that are unlikely to be affected by antiretroviral therapy, cohort, calendar year, and use of other antiretrovirals.

FINDINGS

Over 157,912 person-years, 517 patients had a myocardial infarction. We found no associations between the rate of myocardial infarction and cumulative or recent use of zidovudine, stavudine, or lamivudine. By contrast, recent-but not cumulative-use of abacavir or didanosine was associated with an increased rate of myocardial infarction (compared with those with no recent use of the drugs, relative rate 1.90, 95% CI 1.47-2.45 [p=0.0001] with abacavir and 1.49, 1.14-1.95 [p=0.003] with didanosine); rates were not significantly increased in those who stopped these drugs more than 6 months previously compared with those who had never received these drugs. After adjustment for predicted 10-year risk of coronary heart disease, recent use of both didanosine and abacavir remained associated with increased rates of myocardial infarction (1.49, 1.14-1.95 [p=0.004] with didanosine; 1.89, 1.47-2.45 [p=0.0001] with abacavir).

INTERPRETATION

There exists an increased risk of myocardial infarction in patients exposed to abacavir and didanosine within the preceding 6 months. The excess risk does not seem to be explained by underlying established cardiovascular risk factors and was not present beyond 6 months after drug cessation.

Outcome of R1 resection in patients undergoing pancreatico-duodenectomy for pancreatic cancer

BACKGROUND

Pancreatico-duodenectomy (PD) is the only potentially curative treatment for pancreatic cancer, but most surgeons are reluctant to perform a palliative resection. The aim was to define the outcome for microscopically incomplete PD (R1).

METHODS

Ninety-nine consecutive patients underwent laparotomy to perform PD. Sixty-seven patients were resected and 32 underwent palliative bypass (PSB) because of locally advanced disease.

RESULTS

Of the 67 PD, 27 were classified as R0 and 40 as R1. Median survival for R0, R1 and PSB were 24, 18 and 9 months, respectively. Survival in the PSB group was 34% at 1 year and 0% at 2 years. 1-, 2- and 5-year survival in the R0 and R1 groups was 79% and 70%, 48.3% and 39.1%, 21.5% and 9.9%, respectively. Compared to PSB, both other groups were less likely to die over follow-up (p=0.002). Survival was not significantly different between the R0 and R1 groups (p=0.21). Perioperative morbidity and mortality were similar in the PD and PSB groups (29.9% and 3.0% vs 31.3 and 3.1%, respectively, p=1.00).

CONCLUSIONS

Better survival in the resection group and similar perioperative risk would support the decision to perform PD even when there is the possibility of incomplete microscopic clearance.

An audit of viral load in one clinical population to describe features of viraemic patients on antiretroviral therapy

OBJECTIVES

To assess the prevalence of an undetectable viral load (VL) (<50 HIV-1 RNA copies/mL) in a clinical population and to identify those viraemic and at risk of failing antiretroviral therapy (ART).

METHODS

An audit of a complete clinical population on 1 January 2005 via a clinical database and clinical note review.

RESULTS

On 1 January 2005, 1910 patients were under care; 1229/1332 (92%) of those exposed to ART for >16 weeks had a VL of <50 copies/mL. We examined 49/56 case notes of viraemic patients to identify explanations for viraemia. Common reasons included previous initial mono- or dual therapy, adherence problems, more advanced HIV disease, concomitant medications, physical and mental health issues and being less well linked into the service. A review of these patients' current status on 1 April 2007 showed that six of the 49 had since died. However, of those still alive, 20 (47%) had a VL <500 copies/mL.

CONCLUSIONS

The proportion of patients on ART with detectable viraemia is low in current clinical practice. New drugs may help those who are failing because of resistance. However, there is a small minority of patients who, for various reasons, appear unable to maintain sufficient adherence to ART.

Transgenic human CRP is not pro-atherogenic, pro-atherothrombotic or pro-inflammatory in apoE−/− mice

The pathogenic significance, if any, of the epidemiological association between baseline C-reactive protein (CRP) values and future atherothrombotic events is not known. We therefore investigated spontaneous atherosclerosis and atherothrombosis, and systemic markers of inflammation (acute phase proteins), in aged, normal diet-fed, male apolipoprotein E deficient (apoE(-/-)) mice with and without transgenic expression of human CRP. At 18 months of age, aortic atherosclerosis was extensive but with no significant difference in plaque size between C57BL/6apoE(-/-) mice with (apoE(-/-)-hCRP(+)) and without transgenic human CRP (apoE(-/-)). Atherosclerotic lesions in brachiocephalic arteries were typically complex and layered, with extensive fibrotic-cholesterol deposits, calcification and occasional recent intraplaque haemorrhage and thrombus, but with no significant overall differences between apoE(-/-) and apoE(-/-)-hCRP(+) animals. Concentrations of mouse serum amyloid P component (SAP) were essentially normal throughout and did not differ between apoE(-/-) and apoE(-/-)-hCRP(+) mice, or between wild-type (apoE(+/+)) and apoE(-/-) mice, regardless of human CRP expression. Mouse serum amyloid A protein (SAA), and human CRP concentrations were modestly but significantly higher in apoE(-/-)-hCRP(+) than in apoE(+/+)-hCRP(+) animals, but mouse SAA values were unaffected by transgenic expression of human CRP in either background. Thus, there was no evidence in this 18 month study of apoE(-/-), and control apoE(+/+) mice, that transgenic human CRP was pro-atherogenic, pro-inflammatory or pro-atherothrombotic.

Prognostic importance of anaemia in HIV type-1-infected patients starting antiretroviral therapy: collaborative analysis of prospective cohort studies

BACKGROUND

In HIV type-1-infected patients starting highly active antiretroviral therapy (HAART), the prognostic value of haemoglobin when starting HAART, and of changes in haemoglobin levels, are not well defined.

METHODS

We combined data from 10 prospective studies of 12,100 previously untreated individuals (25% women). A total of 4,222 patients (35%) were anaemic: 131 patients (1.1%) had severe (<8.0 g/dl), 1,120 (9%) had moderate (male 8.0-<11.0 g/dl and female 8.0- < 10.0 g/dl) and 2,971 (25%) had mild (male 11.0- < 13.0 g/ dl and female 10.0- < 12.0 g/dl) anaemia. We separately analysed progression to AIDS or death from baseline and from 6 months using Weibull models, adjusting for CD4+ T-cell count, age, sex and other variables.

RESULTS

During 48,420 person-years of follow-up 1,448 patients developed at least one AIDS event and 857 patients died. Anaemia at baseline was independently associated with higher mortality: the adjusted hazard ratio (95% confidence interval) for mild anaemia was 1.42 (1.17-1.73), for moderate anaemia 2.56 (2.07-3.18) and for severe anaemia 5.26 (3.55-7.81). Corresponding figures for progression to AIDS were 1.60 (1.37-1.86), 2.00 (1.66-2.40) and 2.24 (1.46-3.42). At 6 months the prevalence of anaemia declined to 26%. Baseline anaemia continued to predict mortality (and to a lesser extent progression to AIDS) in patients with normal haemoglobin or mild anaemia at 6 months.

CONCLUSIONS

Anaemia at the start of HAART is an important factor for short- and long-term prognosis, including in patients whose haemoglobin levels improved or normalized during the first 6 months of HAART.

Cardiovascular risk and choice of HIV drug regimen

Since the introduction of combination antiretroviral therapy (cART), there have been many conflicting reports linking its use to the development of cardiovascular disease (CVD). Most antiretroviral drugs have been associated with the development of lipid abnormalities to some degree. However, whereas several large observational studies have reported a link between the use of cART (particularly protease inhibitors) and CVD, evidence linking specific antiretroviral drugs to CVD is limited. Much of the evidence linking cART to the development of dyslipidemia derives from randomized trials. However, given the relative infrequency of CVD in most HIV-positive populations, these may be inadequately powered to demonstrate a link with clinical events. In contrast, large observational studies have greater power to describe the development of clinical events but may be affected by bias. This review will describe the current literature linking cART to CVD as well as the limitations of some of the published studies.

Risk of extensive virological failure to the three original antiretroviral drug classes over long-term follow-up from the start of therapy in patients with HIV infection: an observational cohort study

BACKGROUND

The long-term durability of viral-load suppression provided by the three original antiretroviral drugs is not well characterised. We estimated the proportion of patients who had extensive triple-class failure during long-term follow-up and examined characteristics associated with an increased rate of failure.

METHODS

7916 patients who started antiretroviral therapy with three or more drugs were followed up from the time that therapy started until the last viral-load measure. Extensive triple-class virological failure was defined by failure of three subclasses of nucleoside reverse transcriptase inhibitors, a non-nucleoside reverse transcriptase inhibitor, and a ritonavir-boosted protease inhibitor.

FINDINGS

167 patients developed extensive triple-class failure during 27 441 person-years of follow-up. The Kaplan-Meier estimate for the cumulative risk of extensive triple-class failure was 9.2% by 10 years (95% CI 5.0-13.4). There was evidence that this rate has decreased over time (adjusted hazard ratio 0.86 [0.77-0.96] per year more recent; p=0.006). Of the 167 patients with extensive triple-class failure, 101 (60%) subsequently had at least one viral load less than 50 copies per mL. The risk of death by 5 years from the time of extensive triple-class failure was 10.6% (2.4-18.8, nine deaths).

INTERPRETATION

We have shown that extensive virological failure of the three main classes of drugs occurs slowly in routine clinical practice. This finding has implications for the planning of treatment programmes in developing countries, where additional drugs outside these classes are unlikely to be available for some time.

Response to efavirenz-containing regimens in previously antiretroviral-naive HIV-positive patients: the role of gender

BACKGROUND

We investigated the role of gender on response to efavirenz (EFV)-containing regimens in previously antiretroviral-naive patients.

METHODS

All previously antiretroviral-naive individuals from the Royal Free Hospital in London starting EFV from 1996 onward were included. Treatment failure was defined as the first of 2 consecutive viral load measurements >500 copies/mL more than 24 weeks after starting EFV. Standard survival methods were used to assess time to discontinuation and to treatment failure.

RESULTS

Ninety-six women and 337 men were included. Women were mostly of black African ethnicity (64.6%) with a heterosexual risk (94.8%), whereas men were mostly white (66.8%; P < 0.0001) with a homosexual risk (71.2%; P < 0.0001). Women had lower CD4 counts when starting EFV (median [interquartile range [IQR] = 126 [36, 220] cells/mm for women vs. 190 [109, 268] cells/mm for men; P = 0.0003). After 48 and 96 weeks, 38.8% (95% confidence interval [CI]: 28.8% to 48.7%) and 56.3% (95% CI: 45.8% to 66.9%) of women had discontinued EFV compared with 28.3% (95% CI: 23.4% to 33.2%) and 41.8% (95% CI: 36.3% to 47.3%) of men (P = 0.005). The percentage experiencing failure by 48 and 96 weeks when ignoring treatment changes but censoring at the date of discontinuing all treatment was 1.3% (0.0%, 3.9%) and 4.4% (0.0%, 9.3%) for women compared with 3.8% (1.6%, 6.0%; P = 0.49) and 5.8% (3.0%, 8.6%) for men. Median (IQR) CD4 count increases at 48 weeks were +166 (+89, +239) cells/mm for women and +176 (+93, +263) cells/mm for men.

CONCLUSIONS

Women seem to have comparable virologic and immunologic outcomes to first-line EFV-containing regimens compared with men, although they are more likely to discontinue the drug.

Differential effects of prednisolone and azathioprine on the development of human cytomegalovirus replication post liver transplantation

BACKGROUND

We sought to investigate the impact of different immunosuppressive regimens on human cytomegalovirus (HCMV) incidence and replication dynamics in a cohort of 256 patients after liver transplantation.

METHODS

A time-updated approach was used to determine the risk of developing HCMV replication (>200 genomes/mL blood) within the first 100 days after liver transplantation according to the immunosuppressive regimen being received at specific time points.

RESULTS

In patients receiving tacrolimus, the addition of prednisolone was associated with a significant increased risk of HCMV replication both at baseline (relative rate of infection [RRI]=4.34; P=0.0001) and in a time-updated analysis (RRI=4.68; P=0.0001). However, the addition of azathioprine substantially reduced the risk of HCMV replication to that observed with tacrolimus alone. As expected donor/recipient HCMV serostatus was also a risk factor for viraemia. Multivariable models showed that the tacrolimus plus prednisolone regimen and donor/recipient serostatus were independent risk factors for HCMV replication. Viral replication dynamics showed that the duration of HCMV viraemia, the peak viral load, and the growth rate of HCMV were greatest in patients receiving tacrolimus plus prednisolone although these differences did not reach statistical significance.

CONCLUSIONS

The combination of prednisolone plus tacrolimus as baseline immunosuppression after liver transplantation is associated with a high risk of HCMV replication. This effect can be negated by the addition of azathioprine.

Late Diagnosis of HIV Infection: Epidemiological Features, Consequences and Strategies to Encourage Earlier Testing

A substantial proportion of HIV-infected individuals do not present for HIV testing until late in infection; these individuals are often ill, have a high mortality risk, and are less likely to respond to treatment when initiated. Furthermore, late presentation means that opportunities to reduce onward transmission, either by reducing high-risk behaviours or by reducing an individual's infectivity, are missed. The proportion of HIV-infected individuals who present late has remained relatively stable over the past decade, despite several attempts to encourage earlier diagnosis. Late presenters tend to be those at lower perceived risk of infection, those who are not routinely offered HIV testing, and are often from marginalized groups. Strategies that encourage earlier testing, including routine HIV testing in healthcare settings where high-risk individuals attend frequently, the availability of HIV testing services in non-medical settings, and partner notification schemes or peer-led projects to encourage high-risk individuals to attend for testing, may all increase the proportion of HIV-infected individuals who are aware of their HIV status, thus helping to control the spread of the epidemic. This review summarizes recent evidence on the epidemiology of late presentation and its impact on clinical progression, and describes several key strategies that may encourage earlier diagnosis.

Increased duration of viral suppression is associated with lower viral rebound rates in patients with previous treatment failures

OBJECTIVE

We investigated whether the rate of viral rebound decreases with increasing duration of viral suppression and, if so, whether rebound rates in patients previously failing antiretroviral regimens ultimately decline to levels as low as those seen in patients who have never experienced virological failure.

METHODS

All patients from the UK CHIC Study (n = 21 256) who achieved a viral load (VL) of < or = 50 copies/ml while receiving HAART were followed until viral rebound (two consecutive VL > 400 copies/ml). Patients could re-enter the analysis if they experienced a subsequent VL < or = 50 copies/ml. Rebound rates were calculated according to the number of regimens previously failed and duration of viral suppression.

RESULTS

Of 12 648 patients on HAART 10 237 (80.9%) achieved a VL < or = 50 copies/ml. During 26 494 person-years (PY) of follow-up, 1853 (18.1%) patients experienced at least one viral rebound 'event', with 2460 events in total [rebound rate, 9.3 (range, 8.9-9.7)/100 PY). Within the first year of viral suppression, the rate of viral rebound was 8.3 (7.5-9.1)/100 PY in patients who had not previously failed treatment, increasing to 32.7 (27.6-37.8)/100 PY in patients who had failed more than four regimens. Irrespective of previous treatment failure, rebound rates in those who remained suppressed for > 4 years were similar to those in patients who had at no time experienced treatment failure.

CONCLUSION

After around 4 years of viral suppression rebound rates in individuals with multiple prior treatment failures approach those of individuals with no prior treatment failure.