Epidemiological modelling (including economic modelling) and its role in preventive drug therapy

In contrast to curative therapies, preventive therapies are administered to largely healthy individuals over long periods. The risk-benefit and cost-benefit ratios are more likely to be unfavourable, making treatment decisions difficult. Drug trials provide insufficient information for treatment decisions, as they are conducted on highly selected populations over short durations, estimate only relative benefits of treatment and offer little information on risks and costs. Epidemiological modelling is a method of combining evidence from observational epidemiology and clinical trials to assist in clinical and health policy decision-making. It can estimate absolute benefits, risks and costs of long-term preventive strategies, and thus allow their precise targeting to individuals for whom they are safest and most cost-effective. Epidemiological modelling also allows explicit information about risks and benefits of therapy to be presented to patients, facilitating informed decision-making.

The role of impulsivity in the development of substance use and eating disorders

Impulsivity is now widely viewed as a multidimensional construct consisting of a number of related dimensions. Although many measures of impulsivity are correlated, most recent factor analyses support at least a two-factor model. In the current paper, these two factors have been labelled reward sensitivity, reflecting one of the primary dimensions of Gray's personality theory, and rash-spontaneous impulsiveness. The evidence supporting the existence of two dimensions of impulsivity is reviewed in relation to substance misuse and binge eating. (C) 2004 Elsevier Ltd. All rights reserved.

PHBHV/PCL microspheres as biodegradable drug delivery systems (DDS) for photodynamic therapy (PDT)

Unloaded microspheres were prepared from polyhydroxybutyrate-co-valerate (PHBHV) and poly(epsilon-caprolactone) (PCL) polymers using the emulsification-solvent evaporation method (EE). The study was conducted to determine the ideal polymeric composition and ideal molecular weight for the microspheres preparation to be used as a Drug Delivery System (DDS) for cancer therapy. In this work, NzPC, a new photosensitizer, has been investigated when incorporated into microspheres of PHBHV/PCL evaluating its application for Photodynamic Therapy (PDT) of neoplastic tissue. The biodegradation studies were conducted to analyze the effects of the incorporation of the NzPC and also to determine the release profiles in vitro condition. We also evaluated the dark toxicity and the photobiological effect of the PHBHV-PCL microspheres in cutaneous melanoma cell line (B-16-A1) used as a biological neoplastic medium.

Randomized Evaluation of Two Drug-Eluting Stents With Identical Metallic Platform and Biodegradable Polymer But Different Agents (Paclitaxel or Sirolimus) Compared Against Bare Stents: 1-Year Results of the PAINT Trial

Objectives: We tested two novel drug-eluting stents (DES), covered with a biodegradable-polymer carrier and releasing paclitaxel or sirolimus, which were compared against a bare metal stent (primary objective). The DES differed by the drug, but were identical otherwise, allowing to compare the anti-restenosis effects of sirolimus versus paclitaxel (secondary objective). Background: The efficacy of novel DES with biodegradable polymers should be tested in the context of randomized trials, even when using drugs known to be effective, such as sirolimus and paclitaxel. Methods: Overall, 274 patients with de novo coronary lesions in native vessels scheduled for stent implantation were randomly assigned (2:21 ratio) for the paclitaxel (n = 111), sirolimus (n = 106), or bare metal stent (n = 57) groups. Angiographic follow-up was obtained at 9 months and major cardiac adverse events up to 12 months. Results: Both paclitaxel and sirolimus stents reduced the 9-month in-stent late loss (0.54-0.44 mm, 0.32-0.43 mm, vs. 0.90-0.45 mm respectively), and 1-year risk of target vessel revascularization and combined major adverse cardiac events (P < 0.05 for both, in all comparisons), compared with controls. Sirolimus stents had lower late loss than paclitaxel stents (P < 0.01), but similar 1-year clinical outcomes. There were no differences in the risk of death, infarction, or stent thrombosis among the study groups. Conclusion: Both novel DES were effective in reducing neointimal hyperplasia and 1-year re-intervention, compared to bare metal stents. Our findings also suggest that sirolimus is more effective than paclitaxel in reducing angiographic neointima, although this effect was not associated with better clinical outcomes. (C) 2009 Wiley-Liss, Inc.

The effects of adolescent cannabis use: How should the empirical evidence inform drug policy for young people? : Meeting abstract

Ethics as a subject is now consistently taught in medical schools within Australia. The theoretical Ethical models used, and the associated clinical discussions, vary between schools. Registrars have further theoretical Ethics teaching within Psychiatry Fellowship Training, and ongoing clinical work that is likely to provide exposure to complex and frequent Ethical dilemmas. As Psychiatry Trainees approach subspecialty training in Child and Adolescent Psychiatry they therefore have a rich experience of both theoretical Ethics teaching and clinical exposure to Ethical issues. In this symposium, the difficulties Child and Adolescent Psychiatry Trainees may have in the integration of multiple theoretical Ethical models are discussed. It is suggested that these difficulties make Ethics Teaching for Child and Adolescent Psychiatry Trainees particularly challenging. This is important given the complex Ethical issues often present when working with Children and their Families. The three main Ethical models of Deontology, Virtue Ethics and Consequentialism are described and their usefulness for the Child and Adolescent Psychiatrist examined. Limitations of these models, and “Four Principles” approaches (such as that of Beauchamp and Childress), for Child and Adolescent Psychiatry, are also considered. Clinical cases are included for discussion. Finally, the ways in which these models may be used to enhance Child and Adolescent Psychiatry Training, and subsequent clinical practice as a Child and Adolescent Psychiatrist, are discussed. The integration of different theoretical Ethical models is considered, with implications identified for clinical practice.

Cost analysis of drug therapy in rheumatoid arthritis

With the aim to compare the cost of treatment for rheumatoid arthritis therapy with desease-modifying antirheumatic drugs (DMARDS) for a 48-month period, were studied five different treatment stage based on clinical protocols recommended by the Brazilian Society of Rheumatology, and then five therapy cycles. The analytical model based on the Markov Analysis, considered chaces for the patient continue in some stages or change between them according with a positive effect on outcomes. Only direct costs were comprised in the analyzed data, like drugs, materials and tests used for monitoring these patients. The results of the model show that the stage in with metotrexato drug is used like monotherapy was cost-effective (R$ 113,900,00 for patient during 48 months), followed by refractory patient (R$ 1,554,483,43), those that use therapy triplicate followed by infleximable drug (R$ 1, 701, 286.76), the metotrexato intolearant patient (R$ 2,629,919,14), and final the result from that use metotrexato and infliximable in the beginning (R$ 9,292,879,31). The sensitivity analysis confirm this results, when alternate the efficacy of metotrexato and infliximabe.

A method for drug infusion into the lateral median eminence and arcuate nucleus of sheep

The role of catecholamines in the control of the GnRH pulse generator is unclear as studies have relied on the use of peripheral or intracerebroventricular injections, which lack specificity in relation to the anatomical site of action. Direct brain site infusions have been used, however, these are limited by the ability to accurately target small brain regions. One such area of interest in the control of GnRH is the median eminence and arcuate nucleus within the medial basal hypothalamus. Here we describe a method of stereotaxically targeting this area in a large animal (sheep) and an infusion system to deliver drugs into unrestrained conscious animals. To test our technique we infused the dopamine agonist, quinpirole or vehicle into the medial basal hypothalamus of ovariectomised ewes. Quinpirole significantly suppressed LH pulsatility only in animals with injectors located close to the lateral median eminence. This in vivo result supports the hypothesis that dopamine inhibits GnRH secretion by presynaptic inhibition in the lateral median eminence. Also infusion of quinpirole into the medial basal hypothalamus suppressed prolactin secretion providing in vivo evidence that is consistent with the hypothesis that there are stimulatory autoreceptors on tubero-infundibular dopamine neurons. (C) 1997 Elsevier Science B.V.

Outcomes and safety of drug provocation tests

Drug provocation tests (DPTs) are considered the gold standard for identifying adverse drug reactions (ADRs). The aim of this study was to analyze DPT results and discuss severe systemic reactions associated with them. This was a retrospective analysis of 500 patients with ADRs who sought treatment and were submitted to DPTs when indicated between 2006 and 2010. We performed DPTs according to the European Network for Drug Allergy recommendations. Single-blind, placebo-controlled DPTs were performed with antibiotics, local anesthetics, and nonsteroidal anti-inflammatory drugs, as well as with other drugs. Patient characteristics, DPT results, and reactions were analyzed. The sample comprised 198 patients (80.8% of whom were female patients) submitted to 243 DPTs. Ages ranged from 9 to 84 years (mean, 39.9 years). The 243 DPTs were performed with local anesthetics (n = 93), antibiotics (n = 19), acetaminophen (n = 44), benzydamine (n = 33), COX-2 inhibitors (n = 26), dipyrone (n = 7), aspirin (n = 4), or other drugs (n = 17). The results of 4 tests (1.6%) were inconclusive, whereas those of 10 (4.1%) revealed positive reactions to antibiotics (2/19), COX-2 inhibitors (2/26), acetaminophen (3/44), and local anesthetics (3/93). Two severe reactions were observed: cephalexin-induced anaphylactic shock and bupivacaine-induced anaphylaxis without shock. Four patients (2.0%) reacted to the placebo before administration of the drug. Drug provocation tests are safe for use in clinical practice but they should be placebo-controlled and should be performed under the supervision of an allergist. To confirm a presumptive diagnosis and to manage allergies appropriately, it is crucial to perform DPTs. (Allergy Asthma Proc 32:301-306, 2011; doi: 10.2500/aap.2011.32.3450)