Modelling the consumption of anxiolytics and its addictive behaviour

Background: Population-based anxiolytics consumption (AX) is a widely debated subject because long-term AX may lead to tolerance and addiction. This study aims to obtain mathematical models that identify the various behaviours in AX prescription in accordance with gender, age and the continuous prescription of other drugs associated with chronic diseases.Methods: Data were obtained from an electronic prescriptions database (n=12,211,992) received by patients (n=504,224) visiting the Primary Health Care Centres in the province of Castellón (East Spain) in 2009. A linear regression model was used to explain the number of defined daily doses (DDD) of AX prescribed in accordance with age, gender and more than 5 prescriptions of any drug associated with chronic diseases other than AX. We used the logistic regression model to quantify the joint influence of the explanatory variables on the likelihood (L) of prescribing increasingly high DDD of AX.Results: The mean annual DDD per patient was 133.13, and the DDD prescribed was 38.06 day/1000 inhabitants. Few differences, although significant, in prescriptions per gender were observed; males received fewer prescriptions than females. Conversely, differences in age groups were substantial; the older subjects become, the higher the prescribed DDD, although these differences disappeared after the age of 65. AX use was also positively associated with the presence of comorbidity: depression, psychosis and epilepsy. Sporadic AX prescriptions were not associated with any factor, except continuous use.Conclusions: The prevalence of prescribing AX in the general population visiting the primary health centres in Castellón is over 16%. Prescriptions and the DDD of AX are barely higher for females than for males, and age is the most influential factor; the older the patient, the higher the number of prescribed DDD. The likelihood of potentially addictive behaviours is higher among the elderly and patients with comorbidity, mainly those patients with other chronic psychiatric conditions. © 2010 Elsevier Ltd.Guadalajara Olmeda, MN.; Barrachina Martínez, I.; De La Poza, E.; Vivas Consuelo, DJJ.; Caballer Tarazona, M. (2011). Modelling the consumption of anxiolytics and its addictive behaviour. Mathematical and Computer Modelling. 54(7):1626-1633. https://doi.org/10.1016/j.mcm.2010.12.036S1626163354

Modeling Spanish anxiolytic consumption: Economic, demographic and behavioral influences

Anxiolytics (AX) are the psychotropic drugs prescribed for the treatment of anxiety and insomnia for 2–4 weeks, for longer periods of consumption (>1 month) may lead to the development of tolerance or addiction. In fact, its prescription was 16% of the total pharmaceutical expenditure in Spain in 2007. This paper deals with the development of a mathematical model describing the dynamic of the addiction to AX for the case study of the Spanish region of Castellón. The reasons believed to cause the development of addicts to AX are the economic situation, the marriage termination and the social contact. The simulations performed to forecast the addicts rate for the period 2010–2014 showed an increase from 6% in 2010 to 14% in 2014 with a fluctuation of about 2% between the possible economic scenarios. Finally, the analysis of sensitivity of the rate of addicts to the fluctuation of the social contact parameters was performed, letting us estimate its impact on the pharmaceutical expenditure.De La Poza, E.; Guadalajara Olmeda, MN.; Jódar Sánchez, LA.; Merello Giménez, P. (2013). Modeling Spanish anxiolytic consumption: Economic, demographic and behavioral influences. Mathematical and Computer Modelling. 57(7):1619-1624. https://doi.org/10.1016/j.mcm.2011.10.020S1619162457

Economic incentives in outpatient care and patient demand for pharmaceuticals. A study of antibiotics and addictive drugs prescriptions

The questions asked in this thesis relate to the economic incentives and characteristics of the health care market, which may result in suboptimal drug prescription. We consider two types of pharmaceuticals, such as antibiotics and addictive drugs. These pharmaceuticals are interesting because their use/misuse is associated with costs both at the individual and societal levels. The decision about the prescription of both antibiotics and addictive drugs is ideally made by a doctor, and over-the-counter sales are not available. A good share of the prescriptions is made in outpatient care or primary care (a part of outpatient care). This market is characterised by asymmetric information and may suffer from economic disincentives, which, together with patient-induced demand, may result in drug misuse. Thus there is a need for solutions aimed to facilitate optimal drug consumption, i.e. reducing consumption to a minimum consumption level, given that patients are effectively treated. This thesis considers several characteristics of the outpatient care market, such as free choice of provider, competition, and financial incentives within a health care centre to be important factors contributing to drug misuse. Knowledge about driving mechanisms is important for understanding how policies for more efficient antibiotic and addictive drugs consumption can be achieved. The first paper in the thesis relates to the ownership type of health care centres. It finds that private health care centres in the Västerbotten county of Sweden have a higher share of prescriptions for antibiotics than public ones. The second paper focuses on the competition between general practitioners and antibiotic prescription in Norwegian municipalities. The paper shows that the level of competition may be an important factor contributing to a more frequent antibiotic prescription. The third paper relates to the presence of free choice of the health care provider and uses the prescription data from Västerbotten county of Sweden to investigate patients' demand for addictive drugs and how a strategy to switch providers may affect individual drug consumption

Expanding the definition of addiction: DSM-5 vs. ICD-11.

While considerable efforts have been made to understand the neurobiological basis of substance addiction, the potentially "addictive" qualities of repetitive behaviors, and whether such behaviors constitute "behavioral addictions," is relatively neglected. It has been suggested that some conditions, such as gambling disorder, compulsive stealing, compulsive buying, compulsive sexual behavior, and problem Internet use, have phenomenological and neurobiological parallels with substance use disorders. This review considers how the issue of "behavioral addictions" has been handled by latest revisions of the Diagnostic and Statistical Manual of Mental Disorders (DSM) and the International Classification of Diseases (ICD), leading to somewhat divergent approaches. We also consider key areas for future research in order to address optimal diagnostic classification and treatments for such repetitive, debilitating behaviors.Wellcome-trust and Academy of Medical Sciences

New Pharmacological Agents to Aid Smoking Cessation and Tobacco Harm Reduction: What has been Investigated and What is in the Pipeline?

A wide range of support is available to help smokers to quit and aid attempts at harm reduction, including three first-line smoking cessation medications: nicotine replacement therapy, varenicline and bupropion. Despite the efficacy of these, there is a continual need to diversify the range of medications so that the needs of tobacco users are met. This paper compares the first-line smoking cessation medications to: 1) two variants of these existing products: new galenic formulations of varenicline and novel nicotine delivery devices; and 2) twenty-four alternative products: cytisine (novel outside of central and eastern Europe), nortriptyline, other tricyclic antidepressants, electronic cigarettes, clonidine (an anxiolytic), other anxiolytics (e.g. buspirone), selective 5-hydroxytryptamine (5-HT) reuptake inhibitors, supplements (e.g. St John’s wort), silver acetate, nicobrevin, modafinil, venlafaxine, monoamine oxidase inhibitors (MAOI), opioid antagonist, nicotinic acetylcholine receptors (nAChR) antagonists, glucose tablets, selective cannabinoid type 1 receptor antagonists, nicotine vaccines, drugs that affect gamma-aminobutyric acid (GABA) transmission, drugs that affect N-methyl-D-aspartate receptors (NMDA), dopamine agonists (e.g. levodopa), pioglitazone (Actos; OMS405), noradrenaline reuptake inhibitors, and the weight management drug lorcaserin. Six criteria are used: relative efficacy, relative safety, relative cost, relative use (overall impact of effective medication use), relative scope (ability to serve new groups of patients), and relative ease of use (ESCUSE). Many of these products are in the early stages of clinical trials, however, cytisine looks most promising in having established efficacy and safety and being of low cost. Electronic cigarettes have become very popular, appear to be efficacious and are safer than smoking, but issues of continued dependence and possible harms need to be considered

Smoking cessation for improving mental health (Protocol)

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To investigate the association between tobacco smoking cessation and subsequent mental health outcomes

Updating the Lambda modes of a nuclear power reactor

[EN] Starting from a steady state configuration of a nuclear power reactor some situations arise in which the reactor configuration is perturbed. The Lambda modes are eigenfunctions associated with a given configuration of the reactor, which have successfully been used to describe unstable events in BWRs. To compute several eigenvalues and its corresponding eigenfunctions for a nuclear reactor is quite expensive from the computational point of view. Krylov subspace methods are efficient methods to compute the dominant Lambda modes associated with a given configuration of the reactor, but if the Lambda modes have to be computed for different perturbed configurations of the reactor more efficient methods can be used. In this paper, different methods for the updating Lambda modes problem will be proposed and compared by computing the dominant Lambda modes of different configurations associated with a Boron injection transient in a typical BWR reactor. (C) 2010 Elsevier Ltd. All rights reserved.This work has been partially supported by the Spanish Ministerio de Educacion y Ciencia under projects ENE2008-02669 and MTM2007-64477-AR07, the Generalitat Valenciana under project ACOMP/2009/058, and the Universidad Politecnica de Valencia under project PAID-05-09-4285.González Pintor, S.; Ginestar Peiro, D.; Verdú Martín, GJ. (2011). Updating the Lambda modes of a nuclear power reactor. Mathematical and Computer Modelling. 54(7):1796-1801. https://doi.org/10.1016/j.mcm.2010.12.013S1796180154

Application of the simultaneous equation models to temporary disability prescriptions in primary health care centres

[EN] Non-medical characteristics of primary healthcare centres (PHCs) influence the prescription of temporary disability leaves (incidence and absence rates) due to anxiety, as studied in the Valencian Community (E Spain; 5,111,706 inhabitants, 2009), where 485 centres (66%) were analysed. A structural two-equation model was used to explain which centres' factors impact prescriptions more. This model determined the influence of PHCs' factors (location, delay in specialized care, sick leave duration, etc.) on the incidence and absence rates, and on the interdependence between both rates. The results suggest the need to improve centres' management (clinical guidelines) and labour market regulations, and to control the disability benefits paid. © 2013 © 2013 Taylor & Francis.Guadalajara Olmeda, MN.; Barrachina Martínez, I. (2014). Application of the simultaneous equation models to temporary disability prescriptions in primary health care centres. International Journal of Computer Mathematics. 91(2):252-260. doi:10.1080/0020716.2013.808334S25226091

MODELIZACIÓN MATEMÁTICA DEL EFECTO DE LA ECONOMÍA EN DESORDENES DEL COMPORTAMIENTO: ADICCIONES, COSTES PERSONALES Y SOCIALES

Este trabajo trata sobre el conocimiento de la dinámica de tres patologías de trastorno del control de impulsos: la adicción al trabajo, a las compras y al consumo de ansiolíticos. El objetivo de la presente tesis es el de proponer tres modelos matemáticos, basados en ecuaciones en diferencias, especí¿cos para cada una de estas adicciones, que permitan predecir la prevalencia de estos trastornos conductuales (adicción al trabajo, a las compras y a los ansiolíticos) bajo diferentes perspectivas económicas. Los resultados destacan una tendencia creciente de la prevalencia de estas adicciones en los próximos años. A partir del número esperado de consumidores, se estiman los costes totales anuales asociados a la prescripción de ansiolíticos soportados por el sector público.Merello Giménez, P. (2013). MODELIZACIÓN MATEMÁTICA DEL EFECTO DE LA ECONOMÍA EN DESORDENES DEL COMPORTAMIENTO: ADICCIONES, COSTES PERSONALES Y SOCIALES [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/27664TESI