Recreational drug use among individuals living with HIV in Europe: review of the prevalence, comparison with the general population and HIV guidelines recommendations

Background: Adherence problems, interactions and higher rate of risk activities have been observed in HIV individuals using recreational drugs. Our aim was to describe recreational drug use in both HIV individuals and general population in Europe, and to assess at what extent HIV guidelines address this issue.

Methods: Data on recreational drug use across Europe were obtained from the European Monitoring Centre for Drugs and Drug Addiction for the general population, and through Pubmed search. for HIV patients. We assessed the incorporation of recreational drug issues in HIV treatment guidelines for the following topics: (a) recreational drugs; (b) adherence to antiretrovirals; (c) interactions; (d) transmission risk. Guidelines included: World Health Organization; European Aids Clinical Society; U.S. Department of Health and Human Services; International Antiviral Society-USA; and seven European national guidelines.

Results: 29 countries reported recreational drug use in general population. The highest prevalences were observed for Cannabis (i.e., 8–10% in Spain, France, and Czech Republic) followed by cocaine, amphetamines and ecstasy. The 13 studies selected in the systematic review showed a great variability in recreational drug use on the HIV population. Apart from classical recreational drugs, we found a relevant use of new drugs including sexual experience enhancers. Polydrug consumption was about 50% in some studies. Most guidelines included general information about recreational drugs, showing great variability on the inclusion of the evaluated topics. We found more specific, evidence-based recommendations on interactions, followed by medication adherence and transmission risk.

Conclusions: Available data on the people living with HIV suggest a higher use of recreational drugs than in the general population, which is already relevant. However, recreational drug issues should be included or addressed more thoroughly in most guidelines.

Subcutaneous preconditioning increases invasion and metastatic dissemination in mouse colorectal cancer models

Mouse colorectal cancer (CRC) models generated by orthotopic microinjection of human CRC cell lines reproduce the pattern of lymphatic, haematological and transcoelomic spread but generate low metastatic efficiency. Our aim was to develop a new strategy that could increase the metastatic efficiency of these models. We used subcutaneous implantation of the human CRC cell lines HCT116 or SW48 prior to their orthotopic microinjection in the cecum of nude mice (SC+ORT). This subcutaneous preconditioning significantly enhanced metastatic dissemination. In the HCT116 model it increased the number and size of metastatic foci in lymph nodes, lung, liver and peritoneum, whereas, in the SW48 model, it induced a shift from non-metastatic to metastatic. In both models the number of apoptotic bodies in the primary tumour in the SC+ORT group was significantly reduced compared with that in the direct orthotopic injection (ORT) group. Moreover, in HCT116 tumours the number of keratin-positive tumour buddings and single epithelial cells increased at the invasion front in SC+ORT mice. In the SW48 tumour model, we observed a trend towards a higher number of tumour buds and single cells in the SC+ORT group but this did not reach statistical significance. At a molecular level, the enhanced metastatic efficiency observed in the HCT116 SC+ORT model was associated with an increase in AKT activation, VEGF-A overexpression and downregulation of β1 integrin in primary tumour tissue, whereas, in SW48 SC+ORT mice, the level of expression of these proteins remained unchanged. In summary, subcutaneous preconditioning increased the metastatic dissemination of both orthotopic CRC models by increasing tumour cell survival and invasion at the tumour invasion front. This approach could be useful to simultaneously study the mechanisms of metastases and to evaluate anti-metastatic drugs against CRC.

High RAB25 expression is associated with good clinical outcome in patients with locally advanced head and neck squamous cell carcinoma

Currently there are no molecular markers able to predict clinical outcome in locally advanced head and neck squamous cell carcinoma (HNSCC). In a previous microarray study, RAB25 was identified as a potential prognostic marker. The aim of this study was to analyze the association between RAB25 expression and clinical outcome in patients with locally advanced HNSCC treated with standard therapy. In a retrospective immunohistochemical study (n = 97), we observed that RAB25-negative tumors had lower survival (log-rank, P = 0.01) than patients bearing positive tumors. In an independent prospective mRNA study (n = 117), low RAB25 mRNA expression was associated with poor prognosis. Using classification and regression tree analysis (CART) we established two groups of patients according to their RAB25 mRNA level and their risk of death. Low mRNA level was associated with poor local recurrence-free (log-rank, P = 0.005), progression-free (log-rank, P = 0.002) and cancer-specific (log-rank, P < 0.001) survival. Multivariate Cox model analysis showed that low expression of RAB25 was an independent poor prognostic factor for survival (hazard ratio: 3.84, 95% confidence interval: 1.93-7.62, P < 0.001). Patients whose tumors showed high RAB25 expression had a low probability of death after treatment. We also found lower RAB25 expression in tumors than in normal tissue (Mann-Whitney U, P < 0.001). Moreover, overexpression of RAB25 in the UM-SCC-74B HNSCC cell line increased cisplatin sensitivity, and reduced cell migration and invasion. Our findings support a tumor suppressor role for RAB25 in HNSCC and its potential use to identify locally advanced patients with a high probability of survival after genotoxic treatment.

[Viscosity changes in thickened water due to the addition of highly prescribed drugs in geriatrics]

INTRODUCTION

Dysphagia is a swallowing disorder with a high incidence in the geriatric patient related with an increased risk for undernutrition and pneumonia due to bronchial aspiration. In this condition, it is usual to add commercial thickeners in liquids, as well as the addition of drugs in this mixture to improve their administration. However, there are no studies regarding the possible change in viscosity produced by their addition.

OBJECTIVES

To assess the change in viscosity of water thickened with commercial products by adding the drugs frequently used in elderly patients.

METHODS

Samples of water mixed with the commercial thickener Resource (modified corn starch) or Nutilis (modified corn starch, maltodextrin, and gums: tara, xhantan, and guar) to achieve an intermediate consistence as "honey". The viscosity of these samples was measured as well as for similar samples to which one of the following drugs was added: galantamine, rivastigmin, ciprofloxacin, cholecalciferol, memantine, fosfomycin, calcium, and amoxicillin/clavulanic acid.

RESULTS

In the samples with Resource thickener we observed decreased viscosity by adding galantamine, memantine, fosfomycin or calcium, and increased viscosity with amoxicillin/clavulanic acid. The viscosity of the samples with Nutilis® decreased with galantamine, rivastigmine, amoxicillin/clavulanic acid, fosfomycin and calcium.

CONCLUSION

The viscosity of water with commercial thickeners may be affected by some drugs or their preservatives, which may influence the swallowing capability. It is recommended to perform further in vitro and in vivo studies in order to adjust these formulations if necessary.

Gene expression signatures and molecular markers associated with clinical outcome in locally advanced head and neck carcinoma

The purpose of this study was to identify molecular markers associated with tumor recurrence and survival in patients with locally advanced head and neck squamous cell carcinoma (HNSCC). We studied the expression profile of 63 pre-treatment tumor biopsies obtained from locally advanced HNSCCs treated with standard treatments. Cluster analysis identified three tumor subtypes associated with significant differences in local recurrence-free survival (LRFS) (P<0.001), progression free-survival (PFS) (P<0.009) and overall survival (OS) (P<0.004). Tumor subtype 1, associated with short LRFS, PFS and OS, showed features of epithelial-mesenchymal transition and undifferentiation. It also overexpressed genes involved in cell adhesion, NF-κB and integrin signalling. Tumor subtype 3, associated with longer LRFS, PFS and OS, showed a high degree of differentiation and overexpressed genes located in chromosomal regions 19q13 and 1q21. Tumor subtype 2, which had an intermediate clinical outcome between subtype 1 and subtype 3, overexpressed genes involved in branching morphogenesis. Finally, we validated the association between gene cluster classification and patient survival using Gene Set Enrichment Analysis and two HNSCC data sets obtained from two independent patient cohorts. In conclusion, we generated a gene prognostic signature associated with survival in locally advanced patients using the expression profile of the pre-treatment tumor biopsy. Independent prospective studies would be necessary to assess if the proposed survival signature could help to guide clinical management of HNSCC.

Ritonavir boosting dose reduction from 100 to 50 mg does not change the atazanavir steady-state exposure in healthy volunteers

OBJECTIVES

To evaluate the pharmacokinetics, tolerability and safety of 300 mg of atazanavir boosted with 100 or 50 mg of ritonavir, both once daily, at steady state.

METHODS

This was a single-blind, multiple-dose, crossover, sequence-randomized trial. Thirteen healthy HIV-1-negative men received witnessed once-daily doses of atazanavir (300 mg) and 100 or 50 mg of ritonavir for 10 days (15 day washout). Atazanavir and ritonavir plasma concentrations were determined for 24 h on day 10. Log-transformed individual pharmacokinetic parameters were compared between treatments (analysis of variance); the difference between treatments on the log scale and 95% CIs were calculated. Fasting cholesterol, triglycerides, glucose and bilirubin plasma levels were measured at the beginning and end of each period and compared (Wilcoxon signed rank test). Gastrointestinal symptoms and other events were recorded.

RESULTS

Ritonavir C(max) and the AUC₀₋₂₄ were lower after the 50 mg booster dose than after 100 mg [geometric mean ratio (GMR) (95% CI), 0.40 (0.31-0.51) and 0.35 (0.29-0.42), respectively]. No differences were observed in atazanavir exposure with 50 or 100 mg of ritonavir [GMR C(max) (95% CI), 1.00 (0.79-1.28); GMR AUC₀₋₂₄ (95% CI), 0.98 (0.79-1.21)]. Atazanavir trough concentration was >0.15 mg/L in all volunteers. Total and low-density lipoprotein cholesterol increased 0.40 mM (P = 0.01) and 0.37 mM (P = 0.003) from their corresponding baseline value during the 100 mg dosing period; there were no significant changes on 50 mg. Mild increases in bilirubin were detected on day 10 after both treatments without differences between treatments.

CONCLUSIONS

In spite of higher exposure to ritonavir with 100 mg, atazanavir exposure was equivalent; the lipid profile was better under the lower booster dose (50 mg).

Absence of veno-occlussive disease in a cohort of multiple myeloma patients undergoing autologous stem cell transplantation with targeted busulfan dosage

BACKGROUND

Plasma concentrations of oral busulfan (BU) were measured in multiple myeloma (MM) patients undergoing autologous peripheral blood stem cell transplantation (ASCT) with a double alkylating conditioning protocol in order to individualise doses of BU based on individual pharmacokinetic parameters and to reduce toxicities related to BU exposure.

PATIENTS AND METHODS

Forty-four consecutive patients with MM participating in the co-operative Spanish protocol were prospectively evaluated. Conditioning regimen prior to autologous infusion consisted of BU followed by melphalan. BU pharmacokinetic parameters were estimated for each patient after the first dose based on measured concentrations and subsequent doses were modified as necessary to achieve target exposure.

RESULTS

Mean BU exposure (AUCss) (+/-DS) before dosage modification range from 3192 to 12 180 ng h/mL. Twenty-six out of 44 (59%) patients required dose adjustment. None of the patients developed hepatic veno-occlusive disease (VOD). Grade > or = II oropharyngeal mucositis was observed in the majority of patients (95%) and the severity of mucositis increased with increasing average steady-state BU plasma concentration. There were four treatment-related deaths: two patients died from multiorgan failure and two of respiratory infections. Of the remaining 40 patients, 15 were in complete remission with negative immunofixation, 21 in partial remission and four in stable disease 3 months after ASCT.

CONCLUSIONS

The results of the present study show the variability in BU pharmacokinetic parameters and suggest the possible relationship between toxicities and BU exposure. Individualising BU dosage in MM patients undergoing ASCT we observed the absence of VOD.

[Relation between the viscosity of enteral diets and mechanical complications in their administration according to the nasogastric catheters]

OBJECTIVE

The use of enteral nutrition has increased enormously over the last few years and at the same time the standard indications for parenteral nutrition, whether in hospitals or at home, have gradually been defined. The most common way to administer enteral nutrition is intermittently and using gravity, through a nasogastric catheter or through gastrostomy. In our daily practice it has been observed that there was at times a considerable delay in the administration of the diet by means of a nasogastric catheter and the tube was sometimes blocked due to its small calibre and/or the excessive viscosity of the formula. It was therefore proposed to study the viscosities of polymeric enteral diets with and without fibre at this hospital to identify the relationship with the time taken for their intermittent, gravity-driven administration through different calibres of nasogastric catheter at the maximum flow rate.

RESULTS

Some of the enteral diets under study exceeded the recommended time for intermittent administration by gravity (20-40 minutes).

CONCLUSIONS

We feel it is essential for the product label to provide information on the optimal calibre of the nasogastric catheter required for administration of the product.

Serum levels of G-CSF, IL-3, IL-6 and GM-CSF after a single intraperitoneal dose of rhG-CSF in lethally irradiated B6D2F1 mice

The objective of this study was to assess the pharmacokinetics of rhG-CSF after a single intraperitoneal injection 2 h post-TBI in B6D2F1 lethally irradiated mice and to analyze the effect of rhG-CSF on the endogenous response of interleukin-3 (IL-3), interleukin-6 (IL-6) and granulocyte-macrophage colony-stimulating factor (GM-CSF) in these animals. For comparison, these cytokine serum levels have also been measured in nonirradiated mice. The serum concentrations of rhG-CSF in irradiated mice were higher than in nonirradiated mice at all time points during the first 60 min after injection. Furthermore, rhG-CSF administration failed to induce detectable endogenous serum levels of IL-3, IL-6 and GM-CSF, at least in the 72-hour period after administration of the rhG-CSF. The radioprotective effect of rhG-CSF in lethally irradiated mice is not mediated by an increase in endogenous serum levels of these three cytokines.

Determination of imipenem in plasma by high-performance liquid chromatography for pharmacokinetic studies in patients

A rapid and simple HPLC method is described for the determination of imipenem in human plasma. After blood collection, plasma was separated by centrifugation and immediately stabilized with 3-morpholinopropanesulfonic acid (MOPS) and ethylene glycol solution (1:1). The sample preparation, before injection into HPLC, was ultrafiltration. The mobile phase was boric acid buffer. The imipenem was detected at 300 nm and cilastatin sodium, coadministered, did not interfere. Calibration curves in human plasma were linear from 0.1 to 100 microg/ml. The limit of detection was 0.030 microg/ml. Inter-day precision at 0.1 microg/ml, determined as the coefficient of variation, was 6.26%. Only 250 microl of plasma was required in our assay. Due to the limited stability of imipenem [G.B. Smith et al., J. Pharm. Sci., 79 (1990) 732], stability studies in plasma were done to establish appropriate storage conditions. The assay was applied to pharmacokinetic studies in patients.

Algorithms for dosage and therapeutic monitoring of theophylline

Theophylline is widely prescribed in Spain. Because this drug has a narrow therapeutic range and high interindividual pharmacokinetic variability, it is essential to adapt the dosage to each patient. In order to simplify the drug individualization we are proposing three algorithms to apply to intravenous loading and maintenance doses and to oral doses. The initial recommended dosages have been established using the pharmacokinetic parameters obtained from patients treated with theophylline in our hospital. Because the pharmacokinetic behavior of theophylline may be different in other populations, dosage requirements may not be the same. A minimum number of blood sample collections is proposed in an attempt to improve the cost-benefit relationship in theophylline therapy.

Massive thyroxine intoxication: evaluation of plasma extraction

Six patients were admitted after erroneous massive intake of levothyroxine (70-1200 mg over an interval of 2-12 days). All patients developed classical symptoms of thyrotoxicosis within 3 days of the first dose; five patients presented grade II-III coma and one became stuporous (days 7-10). Two patients developed left ventricular failure and three had arrhythmias (days 8-11). Total thyroid hormone levels in serum on admission ranged 935-7728 nmol/l for T4 (TT4) and 23-399 nmol/l for T3 (TT3). All patients received treatment with hydrocortisone and Propranolol. Propylthiouracil was also given in 3 cases. Extractive techniques (charcoal haemoperfusion and/or plasmapheresis) were initiated 8-14 days after the first dose of L-T4. The plasma disappearance rate (K) of TT4 with plasmapheresis was 30 times higher, on average, than under standard medical treatment (M). Also, K of TT4 under haemoperfusion was about five times higher than K under M. K changes for TT3 were higher under haemoperfusion than under plasmapheresis. Furthermore, extractive procedures shortened the average half life of TT4, (from 106.5 +/- 44.6 to 59.7 +/- 20.2 h, p less than 0.05).

[Effectiveness of rectal metromidazole in acute infantile appendicitis]

Thirty two consecutive children who underwent surgery for suspected acute appendicitis, were treated with prophylactic metronidazole suppositories. A serum sample was taken at surgery to determine the serum concentration of the drug. After a preoperative dose of 15-20 mg/kg the minimal bactericidal concentration was achieved in almost all cases at the time of anesthetic induction. This drug showed an optimal biodisponibility when used rectally and no side-effects was noted. Neither a wound-infection, nor a wound-sepsis was reported and a satisfactory outcome was registered. We conclude that rectal dosing with metronidazole is effective for prophylactic wound infection in acute appendicitis.