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.

Serum leptin concentrations and fat redistribution in HIV-1-infected children on highly active antiretroviral therapy

OBJECTIVES

HIV-related lipodystrophy is a syndrome of adipose tissue redistribution, dyslipidaemia and insulin resistance. Combination antiretroviral therapy (CART) is a key risk factor. We hypothesized that fat redistribution in HIV-infected children is related to altered endocrine function of adipose tissue, namely leptin secretion.

METHODS

Serum leptin and fat redistribution were measured in 104 HIV-infected children in a prospective observational study from 2003 to 2004. Fat redistribution was defined by clinical observation. Body fatness was estimated using body mass index and four skinfold measurements. Serum leptin was determined using an enzyme-linked immunosorbent assay (Quantikine; R&D Systems, Abingdon, UK). Linear analogue models were used to adjust the leptin concentration for body fatness.

RESULTS

There was no significant difference in serum leptin among children treated with protease inhibitors (PIs), children on non-PI CART and children not treated with CART (P>0.05). When leptin concentrations were adjusted for body fatness, there was again no difference among PI-treated, non-PI-treated and untreated children. Categorization of CART exposure as never, current or past did not change these results.

CONCLUSIONS

There is no evidence that leptin plays any role in lipodystrophy other than reflecting body fatness.

Three-fermion problems in optical lattices

We present exact results for the spectra of three fermionic atoms in a single well of an optical lattice. For the three lowest hyperfine states of 6Li atoms, we find a Borromean state across the region of the distinct pairwise Feshbach resonances. For 40K atoms, nearby Feshbach resonances are known for two of the pairs, and a bound three-body state develops towards the positive scattering-length side. In addition, we study the sensitivity of our results to atomic details. The predicted few-body phenomena can be realized in optical lattices in the limit of low tunneling.

Adverse events and treatment interruption in tuberculosis patients with and without HIV co-infection

BACKGROUND

Serious treatment associated adverse events are thought to occur more frequently in individuals with tuberculosis (TB) who are co-infected with HIV. A study was undertaken to assess the frequency of serious (grade III/IV) adverse events and interruption of anti-TB treatment in the era of effective antiretroviral therapy.

METHODS

The incidence of serious adverse events was retrospectively compared in 312 individuals treated for TB, 156 of whom were co-infected with HIV.

RESULTS

111 HIV infected individuals (71%) received highly active antiretroviral therapy at the same time as anti-TB treatment. Serious adverse events were recorded in 40% HIV infected and 26% HIV uninfected individuals (p = 0.008). Peripheral neuropathy and persistent vomiting were more common in co-infected patients (p<0.001; p = 0.006), although all cause interruption of anti-TB treatment occurred with similar frequency in the two groups (13% in HIV infected patients and 15% in HIV uninfected patients; p = 0.74). In 85% of HIV infected patients and 87% of HIV uninfected individuals this was due to hepatotoxicity, which typically presented within 2 months of starting treatment. The median delay in restarting treatment was 4 weeks, so most individuals required full TB re-treatment.

CONCLUSION

Despite a greater rate of serious (grade III/IV) adverse events among HIV infected individuals, discontinuation of anti-TB treatment occurred with a similar frequency in HIV infected and HIV uninfected individuals.

ESPEN Guidelines on Enteral Nutrition: Wasting in HIV and other chronic infectious diseases

Undernutrition (wasting) is still frequent in patients infected with the human immunodeficiency virus (HIV), despite recent decreases in the prevalence of undernutrition in western countries (as opposed to developing countries) due to the use of highly active antiretroviral treatment. Undernutrition has been shown to have a negative prognostic effect independently of immunodeficiency and viral load. These guidelines are intended to give evidence-based recommendations for the use of enteral nutrition (EN) by means of oral nutritional supplements (ONS) and tube feeding (TF) in HIV-infected patients. They were developed by an interdisciplinary expert group in accordance with officially accepted standards and is based on all relevant publications since 1985. Nutritional therapy is indicated when significant weight loss (>5% in 3 months) or a significant loss of body cell mass (>5% in 3 months) has occurred, and should be considered when the body mass index (BMI) is <18.5 kg/m(2). If normal food intake including nutritional counselling and optimal use of ONS cannot achieve an adequate nutrient intake, TF with standard formulae is indicated. Due to conflicting results from studies investigating the impact of immune-modulating formulae, these are not generally recommended. The results obtained in HIV patients may be extrapolated to other chronic infectious diseases, in the absence of available data.

Resonant fermi gases with a large effective range

We calculate the equation of state of a Fermi gas with resonant interactions when the effective range is appreciable. Using an effective field theory for a large scattering length and large effective range, we show how calculations in this regime become tractable. Our results are model independent, and as an application, we study the neutron matter equation of state at low densities of astrophysical interest 0.002 fm(-3) < rho < 0.02 fm(-3), for which the interparticle separation is comparable to the effective range. We compare our simple results with those of conventional many-body calculations.

Risk factors for the HIV-associated lipodystrophy syndrome in a closed cohort of patients after 3 years of antiretroviral treatment

OBJECTIVE

To identify prevalence and risk factors associated with the HIV-associated lipodystrophy syndrome (HIVLD) after 3 years of antiretroviral therapy, to investigate the diagnostic value of anthropometric measures and to assess the impact of HIVLD on quality of life.

DESIGN AND METHODS

A prospective, cross-sectional, multicentre, observational, cohort study was performed in 27 German teaching hospitals, nonacademic hospitals and private practices. A total of 221 HIV-positive patients commencing antiretroviral therapy between July and September 1996 were studied. The main outcome measure was lipodystrophy, defined as otherwise unexplained truncal fat accumulation and/or fat loss in face or extremities. The analysis consisted of multiple logistic regression models, receiver operating characteristics (ROC) curves for anthropometric measures and visual analogue scales for quality of life.

RESULTS

The prevalence of HIVLD after 3 years was 34%. The following variables were independently associated with HIV-LS: stavudine use > 12 months [odds ratio (OR) 2.1, 95% confidence interval (CI) 1.1-3.9], CD4 count nadir < 200 cells/microL (OR 2.2, CI 1.1-4.6), hypertriglyceridaemia (OR 2.3, CI 1.3-4.2) and nonnucleoside reverse transcriptase inhibitor (NNRTI) intake > 12 months (OR 0.2, CI 0.04-0.87). No cut-off point was found for anthropometric indices with a sensitivity and specificity of > or = 0.8. The mean visual analogue ratings for impaired quality of life, on a scale of 0-10, were: 5.2 (self-esteem), 2.9 (social contacts), 4.2 (sexuality) and 3.5 (daily activities).

CONCLUSIONS

These findings suggest a multifactorial aetiology for HIVLD. Stavudine use and a CD4 count below 200 cells/microL may be associated with an increased risk for the development of HIVLD. In contrast, NNRTI treatment may be associated with a reduced risk. Anthropometric indices were found to be insufficient as a diagnostic tool. Quality of life was severely affected by HIVLD.

Clinical assessment of HIV-associated lipodystrophy syndrome: bioelectrical impedance analysis, anthropometry and clinical scores

BACKGROUND

Diagnosis of the HIV-associated lipodystrophy syndrome is based on clinical assessment, in lack of a consensus about case definition and reference methods. Three bedside methods were compared in their diagnostic value for lipodystrophy.

PATIENTS AND METHODS

Consecutive HIV-infected outpatients (n=278) were investigated, 128 of which also had data from 1997 available. Segmental bioelectrical impedance analysis (BIA) and waist, hip and thigh circumferences were performed. Changes in seven body regions were rated by physicians and patients using linear analogue scale assessment (LASA). Diagnostic cut-off values were searched by receiver operator characteristics.

RESULTS

Lipodystrophy was diagnosed in 85 patients (31%). BIA demonstrated higher fat-free mass in patients with lipodystrophy but not after controlling for body mass index and sex. Segmental BIA was not superior to whole body BIA in detecting lipodystrophy. Fat-free mass increased from 1997 to 1999 independent from lipodystrophy. Waist-hip and waist-thigh ratios were higher in patients with lipodystrophy. BIA, anthropometry and LASA did not provide sufficient diagnostic cut-off values for lipodystrophy. Agreement between methods, and between patient and physician rating, was poor.

CONCLUSION

These methods do not fulfil the urgent need for quantitative diagnostic tools for lipodystrophy. BIA estimates of fat free mass may be biased by lipodystrophy, indicating a need for re-calibration in HIV infected populations.

Risk factors for the HIV-associated lipodystrophy syndrome in a cross-sectional single-centre study

OBJECTIVE

Risk factors for the HIV-associated lipodystrophy syndrome (HALS) were studied in a single-centre, cross-sectional study. -

PATIENTS AND METHODS

278 consecutive HIV-infected outpatients at a German tertiary care centre were enrolled. Changes in body shape were quantified using linear analogue scales. Cumulative treatment duration for each antiretroviral drug, CD4 cells, viral load and age were investigated as potential risk factors for a clinical diagnosis of lipodystrophy syndrome by logistic regression.

RESULTS

HALS was diagnosed in 88 patients. The risk of HALS increased significantly with longer protease inhibitor treatment (relative risk 1.61 (95% confidence interval, 1. 24 to 2.09, per year); older age and a history of low CD4 cell counts were cofactors in this multivariate model, but nucleoside analogues did not contribute significantly. Neither pattern nor severity of disease were predicted by these risk factors. Treatment durations and other risk factors were highly correlated with each other.

CONCLUSIONS

These findings support a pathogenetic role for protease inhibitor toxicity, advanced HIV disease, and ageing. No evidence for an additional effect of nucleoside analogues was found. The high correlation of potential risk factors indicates that this and other available studies may be too small to detect multiple risk factors without major confounding.

Phase angle from bioelectrical impedance analysis remains an independent predictive marker in HIV-infected patients in the era of highly active antiretroviral treatment

BACKGROUND

Highly active antiretroviral treatment (HAART) reduces the risk of wasting in HIV infection and may alter the prognostic weight of wasting. The phase angle from bioelectrical impedance analysis (BIA) can be interpreted as a surrogate marker for the catabolic reaction to chronic HIV infection and opportunistic disease.

OBJECTIVE

Our objective was to assess the prognostic ability of the phase angle in HIV-infected patients in the era of HAART.

DESIGN

Two cross-sectional observation studies were conducted in 1996 and 1997 at a German university outpatient HIV clinic. In the 1996 and 1997 cohorts, HAART was prescribed to 17 of 212 and 168 of 257 patients at baseline and to 179 of 212 and 234 of 257 patients during observation, respectively. Whole-body BIA was assessed at 50 KHz. Time to clinical progression and survival were calculated by using Cox proportional hazard models with time-dependent covariates. Median observation times were 1000 and 515 d for the 1996 and 1997 cohorts, respectively.

RESULTS

Higher phase angle was associated with a lower relative mortality risk, adjusted for viral load and CD4(+) cell count, of 0.49 (95% CI: 0.30, 0.81) per degree in 1996 and of 0.33 (95% CI: 0.18, 0.61) in 1997. The influence of phase angle on time to clinical progression, adjusted for viral load and CD4(+) cell count, was not significant in 1996 but the relative risk was 0.58 (0.36, 0.83) in 1997.

CONCLUSION

Despite the favorable effects of HAART on the nutritional status of HIV-infected persons, low phase angle remains an independent adverse prognostic marker of clinical progression and survival.

Tuberculosis, malnutrition and wasting

Malnutrition predisposes to tuberculosis, and tuberculosis causes 'consumption'. Starting from current advances and historic findings in epidemiology and immunology, we can hope to decipher the effects of macro- and micronutrient deficiency upon tuberculosis, the contribution of immune response to the pathogenesis of wasting, and the best approach to its treatment.

Assessment of intracellular water by whole body bioelectrical impedance and total body potassium in HIV-positive patients

OBJECTIVE

Bioelectrical impedance analysis (BIA) is widely used as bedside assessment of body composition. Body cell mass (BCM) and intracellular water (ICW) are clinically important body compartments. Estimates of ICW obtained from BIA by different calculation approaches were compared to a reference method in male HIV-infected patients.

PATIENTS

Representative subsample of clinically stable HIV-infected outpatients, consisting of 42 men with a body mass index of 22.4 +/- 3.8 kg/m(2)(range, 13-l31 kg/m(2)).

METHODS

Total body potassium was assessed in a whole body counter, and compared to 50 kHz monofrequency BIA and multifrequency bioelectrical impedance spectroscopy. Six different prediction equations for ICW from BIA data were applied. Methods were compared by the Bland-Altman method.

RESULTS

BIA-derived ICW estimates explained 58% to 73% of the observed variance in ICW (TBK), but limits of confidence were wide (-16.6 to +18.2% for the best method). BIA overestimated low ICW (TBK) and underestimated high ICW (TBK) when normalized for weight or height. Mono- and multifrequency BIA were not different in precision but population-specific equations tended to narrower confidence limits.

CONCLUSION

BIA is an unreliable method to estimate ICW in this population, in contrast to the better established estimation of total body water and extracellular water. Potassium depletion in severe malnutrition may contribute to this finding but a major part of the residual between methods remains unexplained.

Fever and sepsis during neutropenia are associated with expansion of extracellular and loss of intracellular water

BACKGROUND AND AIMS

Shifts from intracellular to extracellular water are features of a catabolic reaction to sepsis. Bedside assessment of fluid shifts was carried out in neutropenic patients at high risk of systemic infection.

METHODS

Multifrequency bioelectrical impedance analysis was performed in 41 patients with leukemia or high-malignant lymphoma and chemotherapy-induced neutropenia.

RESULTS

Hydration was stable during afebrile periods except for transient intra- and extracellular dehydration after chemotherapy. The risk of over-hydration and dehydration increased 3-fold during fever. Over-hydration was more severe when occurring during fever. Extracellular water was highly variable and tended to increase, and intracellular water was slowly depleted. During sepsis, these alterations were enhanced. Changes in hydration status did not predict subsequent progression to sepsis because it developed more slowly than other symptoms of infection.

CONCLUSIONS

Extracellular over-hydration and intracellular dehydration are observed in febrile infection in neutropenia, similar to severe sepsis. If the technical limits of bioelectrical impedance are taken into account, this method may be useful for non-invasive monitoring of these features of metabolic stress.

Guillain-Barré syndrome in a patient with non-Hodgkin's lymphoma

We describe a case of Guillain-Barré syndrome (GBS) in a patient with non-Hodgkin's lymphoma (NHL). A 21-year-old woman with a newly diagnosed stage IV high-grade lymphoma (precursor T-cell NHL according to the R.E.A.L. Classification) developed flaccid quadriparesis and bilateral facial diplegia after three weeks of treatment with vincristine, daunorubicin, L-asparaginase and prednisolone. The clinical course and neurological examination were consistent with GBS. Despite treatment with intravenous immunoglobulins her neurological symptoms progressed. Plasmapheresis was therefore initiated followed by intravenous immunoglobulins. After partial remission of neurologic symptoms, induction chemotherapy with cyclophosphamide and cytarabine was continued without any further complication. Three months later, the lymphoma was in complete remission. GBS has been described in Hodgkin's disease and after bone marrow transplantation but is rare in NHL. In patients with NHL who develop neurological symptoms, drug toxicity and nervous system infiltration are the leading cause of neuropathology, but GBS should be considered in the differential diagnosis.

Oral supplements as adjunctive treatment to nutritional counseling in malnourished HIV-infected patients: randomized controlled trial

AIMS

To compare nutritional counseling with and without oral supplements in HIV-infected patients with recent weight loss.

DESIGN

Randomized non-blinded controlled trial, stratified for change in antiretroviral treatment at baseline.

PATIENTS

HIV-infected patients with recent weight loss (> 5% of total, and >3% in the last month).

INTERVENTION

Nutritional counseling to increase dietary intake by 600 kcal/day over 8 weeks; in group A (n=24) by normal food, and in group B (n=26) by a range of fortified drink supplements with a calorific value of 0.6 to 1.5 kcal/ml.

METHODS

Body composition by bioelectrical impedance analysis, dietary intake by 24 h recall.

RESULTS

Fat free mass increased from baseline to week 8 (P<0.05) with no difference between groups A and B (P=0.97). Body cell mass and weight gain were not significant and equal between groups. Assessed at weeks 2 and 4, group B patients consumed 11 +/- 6 kcal/kg as supplements, and their total energy intake was 6 kcal/kg higher than in group A (P<0.01). Total energy intake was not different between groups at weeks 6 and 8.

DISCUSSION

Nutritional counseling and oral supplements are both feasible methods to restore food energy intake in malnourished HIV-infected patients. Although normal food intake is partially replaced, oral supplements may improve the adherence to a weight gain regimen.

Clinical efficacy of protease inhibitor based antiretroviral combination therapy--a prospective cohort study

OBJECTIVES

To analyze virological and clinical efficacy of protease inhibitor based antiretroviral regimens in a cohort of unselected HIV-infected patients.

METHODS

Prospective analysis of all HIV-infected patients started on protease inhibitor therapy until August 31, 1997 in two outpatient clinics. Partial viral suppression was defined as reduction of HIV-RNA at least 1log(10) below baseline and complete viral suppression as reduction below the limit of detection. Risk factors for clinical and virological failure were analyzed by a Cox proportional hazard model.

RESULTS

387 patients (median observation time 381 days) were analyzed. In 312 patients (81%) partial and in 265 (68%) complete viral suppression was observed. Secondary failure occurred in 75 patients and could be reversed in 11/75. The probability of virological failure at one year was 51% for complete and 47% for partial suppression. CD4-cells increased by a median of 101/microl overall and 39/microl for patients without partial virologic suppression. 57 clinical events or deaths occurred in 44 pts. Risk factors for virological failure were AIDS at baseline (RR 1.6) and use of Saquinavir vs. Indinavir or Ritonavir (RR 1.7), for clinical failure AIDS at baseline (RR 4. 9), CD4-cell count (0.74 for increase of 50/microl), degree of viral suppression (RR 0.1 for complete suppression) and PI used (Saquinavir vs. Indinavir or Ritonavir, RR 2.7).

CONCLUSIONS

Virological failure of PI based combination therapy is common and associated with advanced HIV-infection. Clinical failure is associated with advanced HIV-infection and failure to suppress viral replication.

Bioelectrical impedance analysis in HIV-infected patients treated with triple antiretroviral treatment

BACKGROUND

Triple antiretroviral treatment including protease inhibitors (PIs) delays the clinical progression of HIV infection and may thus reduce the risk of malnutrition. However, fat redistribution (lipodystrophy) was recognized recently as a metabolic side effect of PIs.

OBJECTIVE

The study aimed to assess the effect of triple antiretroviral treatment on body composition and on the prevalence of malnutrition.

DESIGN

Two cross-sectional studies, 1 in 1996 (t96; n = 247) and 1 in 1997 (t97; n = 266), were conducted in HIV-infected outpatients. Among patients who participated in both studies, 111 patients started a new antiretroviral treatment including a PI between t96 and t97 and were studied longitudinally. Total body water (TBW), intracellular water (ICW), extracellular water (ECW), and fat mass were estimated by monofrequency bioelectrical impedance analysis (BIA).

RESULTS

Prevalence of malnutrition was reduced by 30-50% from t96 to t97, depending on the definition used. In the longitudinal study, TBW and the ratio between ICW and ECW increased and fat mass decreased (P < 0.001). BIA indicated a greater increase in ICW in 23 (21%) patients with clinically apparent fat redistribution than in patients without this syndrome, but estimates of fat mass changes were not significantly different.

CONCLUSIONS

Triple antiretroviral treatment may protect HIV-infected patients against the development of malnutrition. Whole-body BIA data suggest an increase in appendicular body cell mass associated with improved antiretroviral treatment. However, the method is unreliable in detecting fat redistribution, and current prediction equations will need to be recalibrated for HIV-infected patients receiving highly active antiretroviral treatment.