Prevalence of and factors associated with the use of methylphenidate for cognitive enhancement among university students / Prevalência e fatores associados ao uso de metilfenidato para neuroaprimoramento farmacológico entre estudantes universitários

ABSTRACT Objective To estimate the prevalence of and factors associated with the use of methylphenidate for cognitive enhancement among undergraduate students. Methods Simple random sample of students of the Universidade Federal de Minas Gerais (n=438), invited to answer an online questionnaire about the use of methylphenidate. Data collection occurred from September 2014 to January 2015. The sample was described by means of proportions, means and standard deviations. A multivariate analysis was performed using the Classification and Regression Tree algorithm to classify the cases of use of methylphenidate for cognitive enhancement in groups, based on the exposure variables. Results Out of 378 students included, 5.8% (n=22) reported using methylphenidate for cognitive enhancement; in that, 41% (9/22) in the 4 weeks prior to the survey. The housing situation was the variable most often associated with the use of methylphenidate for cognitive enhancement. Eleven students reported using methylphenidate for cognitive enhancement and other purposes 4 weeks prior to the survey, 27% of whom had no medical prescription to purchase it. Conclusion The use of methylphenidate for cognitive enhancement is frequent among Brazilian undergraduate students and should be considered a serious public health problem, especially due to risks of harm and adverse effects associated with its use.

RESUMO Objetivo Estimar a prevalência e os fatores associados ao uso de metilfenidato para neuroaprimoramento entre estudantes universitários. Métodos Amostra aleatória simples de discentes da Universidade Federal de Minas Gerais (n=438), convidados a responder um questionário online sobre o consumo de metilfenidato. A coleta ocorreu de setembro de 2014 a janeiro de 2015. A amostra foi descrita em termos de proporções, médias e desvio padrão. A análise multivariada foi realizada utilizando o algoritmo Classification and Regression Tree para classificação dos casos de uso do metilfenidato para neuroaprimoramento em grupos, com base nas variáveis de exposição. Resultados Dos 378 alunos incluídos, 5,8% (n=22) declararam ter feito uso de metilfenidato para neuroaprimoramento, sendo 41% (9/22) nas 4 semanas anteriores à pesquisa. A situação da moradia foi a variável mais associada ao uso de metilfenidato para neuroaprimoramento. Relataram o uso do metilfenidato para neuroaprimoramento e outros fins nas 4 semanas anteriores à pesquisa 11 estudantes, sendo que 27% não apresentaram prescrição médica para adquiri-lo. Conclusão O uso de metilfenidato para neuroaprimoramento ocorre no meio acadêmico brasileiro e deve ser considerado sério problema de saúde pública, principalmente diante dos riscos de danos e efeitos adversos associados ao seu uso.

Prevalence of and factors associated with the use of methylphenidate for cognitive enhancement among university students.

OBJECTIVE: To estimate the prevalence of and factors associated with the use of methylphenidate for cognitive enhancement among undergraduate students. METHODS: Simple random sample of students of the Universidade Federal de Minas Gerais (n=438), invited to answer an online questionnaire about the use of methylphenidate. Data collection occurred from September 2014 to January 2015. The sample was described by means of proportions, means and standard deviations. A multivariate analysis was performed using the Classification and Regression Tree algorithm to classify the cases of use of methylphenidate for cognitive enhancement in groups, based on the exposure variables. RESULTS: Out of 378 students included, 5.8% (n=22) reported using methylphenidate for cognitive enhancement; in that, 41% (9/22) in the 4 weeks prior to the survey. The housing situation was the variable most often associated with the use of methylphenidate for cognitive enhancement. Eleven students reported using methylphenidate for cognitive enhancement and other purposes 4 weeks prior to the survey, 27% of whom had no medical prescription to purchase it. CONCLUSION: The use of methylphenidate for cognitive enhancement is frequent among Brazilian undergraduate students and should be considered a serious public health problem, especially due to risks of harm and adverse effects associated with its use.

Prescription, dispensation and marketing patterns of methylphenidate / Padrões de prescrição, dispensação e comercialização de metilfenidato

OBJECTIVE To analyze the patterns and legal requirements of methylphenidate consumption. METHODS We conducted a cross-sectional study of the data from prescription notification forms and balance lists of drugs sales – psychoactive and others – subject to special control in the fifth largest city of Brazil, in 2006. We determined the defined and prescribed daily doses, the average prescription and dispensation periods, and the regional sales distribution in the municipality. In addition, we estimated the costs of drug acquisition and analyzed the individual drug consumption profile using the Lorenz curve. RESULTS The balance lists data covered all notified sales of the drug while data from prescription notification forms covered 50.6% of the pharmacies that sold it, including those with the highest sales volumes. Total methylphenidate consumption was 0.37 DDD/1,000 inhabitants/day. Sales were concentrated in more developed areas, and regular-release tablets were the most commonly prescribed pharmaceutical formulation. In some regions of the city, approximately 20.0% of the prescriptions and dispensation exceeded 30 mg/day and 30 days of treatment. CONCLUSIONS Methylphenidate was widely consumed in the municipality and mainly in the most developed areas. Of note, the consumption of formulations with the higher abuse risk was the most predominant. Both its prescription and dispensation contrasted with current pharmacotherapeutic recommendations and legal requirements. Therefore, the commercialization of methylphenidate should be monitored more closely, and its use in the treatment of behavioral changes of psychological disorders needs to be discussed in detail, in line with the concepts of the quality use of medicines. .

OBJETIVO Analisar padrões e requisitos legais do consumo de metilfenidato. MÉTODOS Estudo transversal realizado em Belo Horizonte, MG, em 2006. Foram analisados dados de notificações de receitas de metilfenidato e de balanços de vendas de medicamentos – psicoativos e outros – sujeitos a controle especial. Determinou-se a dose diária definida, a dose diária prescrita, o período médio de prescrição e de dispensação, bem como a distribuição regional das vendas desse medicamento no município. Foram estimados, ainda, os gastos com a aquisição do medicamento e analisado o perfil de consumo individual do fármaco por meio da Curva de Lorenz. RESULTADOS Os dados dos balanços mensais de comercialização de psicotrópicos cobriram toda a comercialização notificada do fármaco, enquanto aqueles coletados nas notificações de receita cobriram 50,6% das farmácias que o comercializaram, incluindo aquelas de maior volume de venda. O consumo de metilfenidato foi 0,37 DDD/1.000 habitantes/dia. As vendas concentraram-se em áreas mais desenvolvidas e as formulações farmacêuticas de liberação não controlada foram as mais prescritas. A prescrição e a dispensação com dosagens > 30 mg/dia e período de tratamento > 30 dias apresentaram valores em torno de 20,0% em algumas regiões da cidade. CONCLUSÕES O consumo de metilfenidato apresentou-se elevado no município, maior em áreas mais favorecidas economicamente e predominando o consumo de formulações com maior risco de abuso. Tanto a prescrição quanto a dispensação apresentaram características não compatíveis com as recomendações farmacoterapêuticas e determinações legais. O controle de venda do fármaco ...

Lipodystrophy among patients with HIV infection on antiretroviral therapy: a systematic review protocol.

INTRODUCTION: Lipodystrophy is a frequent and disfiguring adverse effect of antiretroviral therapy (ART) in patients with HIV. It affects the quality of life of the patient and adherence to treatment, and generates new needs for comprehensive healthcare services. The aim of this study will be to conduct a systematic review of the literature from observational studies and describe lipodystrophy among patients with HIV infection during current or previous use of ART. METHODS AND ANALYSIS: A systematic review of observational studies published in MEDLINE, CINAHL, LILACS, EMBASE and International Pharmaceutical Abstracts will be carried out. Citations of included studies will be checked to identify additional studies not identified in the electronic searches. It will include any observational study that considered lipodystrophy as the primary or secondary outcome and that had enrolled adolescent and adult patients with HIV infection who were on current or previous ART for at least 6 months. Data extraction and analysis will be performed independently by two reviewers. The extracted data will be discussed, decisions documented and, where necessary, the authors of the studies will be contacted for clarification. Measures of frequency, prevalence and incidence of lipodystrophy will be stratified according to definition, method of diagnosis and risk factors of the outcome. ETHICS AND DISSEMINATION: Ethics is not required given this is a protocol for a systematic review. The findings of this study will be widely disseminated through peer-reviewed publications and conference presentations. Updates of the review will be conducted to inform and guide healthcare practice. PROTOCOL REGISTRATION: PROSPERO-42013005450.

Prescription, dispensation and marketing patterns of methylphenidate.

OBJECTIVE To analyze the patterns and legal requirements of methylphenidate consumption. METHODS We conducted a cross-sectional study of the data from prescription notification forms and balance lists of drugs sales - psychoactive and others - subject to special control in the fifth largest city of Brazil, in 2006. We determined the defined and prescribed daily doses, the average prescription and dispensation periods, and the regional sales distribution in the municipality. In addition, we estimated the costs of drug acquisition and analyzed the individual drug consumption profile using the Lorenz curve. RESULTS The balance lists data covered all notified sales of the drug while data from prescription notification forms covered 50.6% of the pharmacies that sold it, including those with the highest sales volumes. Total methylphenidate consumption was 0.37 DDD/1,000 inhabitants/day. Sales were concentrated in more developed areas, and regular-release tablets were the most commonly prescribed pharmaceutical formulation. In some regions of the city, approximately 20.0% of the prescriptions and dispensation exceeded 30 mg/day and 30 days of treatment. CONCLUSIONS Methylphenidate was widely consumed in the municipality and mainly in the most developed areas. Of note, the consumption of formulations with the higher abuse risk was the most predominant. Both its prescription and dispensation contrasted with current pharmacotherapeutic recommendations and legal requirements. Therefore, the commercialization of methylphenidate should be monitored more closely, and its use in the treatment of behavioral changes of psychological disorders needs to be discussed in detail, in line with the concepts of the quality use of medicines.

Heparin-induced thrombocytopenia: a review of concepts regarding a dangerous adverse drug reaction.

Heparin is a natural agent with antithrombotic action, commercially available for therapeutic use as unfractionated heparin and low molecular weight heparin. Heparin-induced thrombocytopenia (HIT) is a serious adverse reaction to heparin that promotes antibody-mediated platelet activation. HIT is defined as a relative reduction in platelet count of 50% (even when the platelet count at its lowest level is above>150 x 10(9)/L) occurring within five to 14 days after initiation of the therapy. Thrombocytopenia is the main feature that directs the clinical suspicion of the reaction and the increased risk of thromboembolic complications is the most important and paradoxical consequence. The diagnosis is a delicate issue, and requires a combination of clinical probability and laboratory tests for the detection of platelet activation induced by HIT antibodies. The absolute risk of HIT has been estimated between 1% and 5% under treatment with unfractionated heparin, and less than 1% with low molecular weight heparin. However, high-quality evidence about the risk of HIT from randomized clinical trials is scarce. In addition, information on the frequency of HIT in developing countries is not widely available. This review aims to provide a better understanding of the key features of this reaction and updated information on its frequency to health professionals and other interested parties. Knowledge, familiarity, and access to therapeutic options for the treatment of this adverse reaction are mandatory to minimize the associated risks, improving patient safety.

Heparin-induced thrombocytopenia: a review of concepts regarding a dangerous adverse drug reaction / Trombocitopenia induzida por heparina: revisão de conceitos de uma importante reação adversa a medicamentos

Heparin is a natural agent with antithrombotic action, commercially available for therapeutic use as unfractionated heparin and low molecular weight heparin. Heparin-induced thrombocytopenia (HIT) is a serious adverse reaction to heparin that promotes antibodymediated platelet activation. HIT is defined as a relative reduction in platelet count of 50% (even when the platelet count at its lowest level is above > 150 x 10(9)/L) occurring within five to 14 days after initiation of the therapy. Thrombocytopenia is the main feature that directs the clinical suspicion of the reaction and the increased risk of thromboembolic complications is the most important and paradoxical consequence. The diagnosis is a delicate issue, and requires a combination of clinical probability and laboratory tests for the detection of platelet activation induced by HIT antibodies. The absolute risk of HIT has been estimated between 1% and 5% under treatment with unfractionated heparin, and less than 1% with low molecular weight heparin. However, high-quality evidence about the risk of HIT from randomized clinical trials is scarce. In addition, information on the frequency of HIT in developing countries is not widely available. This review aims to provide a better understanding of the key features of this reaction and updated information on its frequency to health professionals and other interested parties. Knowledge, familiarity, and access to therapeutic options for the treatment of this adverse reaction are mandatory to minimize the associated risks, improving patient safety.

A heparina é um agente natural com ação antitrombótica, sendo disponibilizadas para uso terapêutico a heparina não fracionadaeaheparina de baixo peso molecular. A trombocitopenia induzida por heparina (TIH) é uma reação adversa grave às heparinas mediada por anticorpos que promovem ativação de plaquetas. A TIH é definida como uma redução rela- tiva na contagem de plaquetas de 50% (mesmo se a contagem de plaquetas no seu nível mais baixo estiver acima 150 x 10(9)/L) que pode ocorrer no período de cinco a 14 dias após o início da terapia com o medicamento. A trombocitopenia é a principal característica que direciona a suspeita clínica da reação, sendo o aumento do risco de complicações tromboembólicas a consequência mais importante e paradoxal. O diagnóstico é uma questão delicada e requer a combinação da probabilidade clínica com testes laboratoriais para detectar a ativação plaquetária induzida pelos anticorpos da TIH. O risco absoluto de TIH tem sido estimado entre 1 e 5% no tratamento com heparina não fracionada e inferior a 1% no uso de heparina de baixo peso molecular. No entanto, evidências de alta qualidade provenientes de ensaios clínicos randomizados sobre a frequência dessa reação são escassas. Além disso, informações sobre a frequência de TIH em países em desenvolvimento não são amplamente disponíveis. Esta revisão teve como objetivo fornecer aos profissionais de saúde e demais interessados um melhor conhecimento sobre a TIH e as principais características dessa reação, bem como apresentar dados atualizados sobre a frequência da mesma. Conhecimento, familiaridade e acesso a opções terapêuticas para o tratamento dessa reação adversa são necessários para minimizar os riscos associados, melhorando a segurança do paciente.

Preeclampsia and ABO blood groups: a systematic review and meta-analysis.

Preeclampsia (PE) is a multifactorial pregnancy-specific syndrome which represents one of the leading causes of maternal mortality worldwide. Inherited thrombophilia have been investigated as risk factor for the development of PE and it is currently known that ABO blood group may impact haemostatic balance, having the non-O blood groups (A, B or AB) subjects increased risk for thrombus formation, as compared to those of group O. We performed a systematic review of the literature for published studies investigating whether ABO blood groups could influence PE developing. A sensitive search of four databases identified 45 unique titles. The retrieved papers were assessed independently by authors and a rigorous process of selection and data extract was conduct. Methodological quality of the included studies was also evaluated. Two studies met eligibility criteria. As a main finding of our systematic review, an association between the AB blood group and the occurrence of PE was detected based on two original studies. Considering the role of ABO blood groups on the hemostatic process and thrombus formation, special attention should be given to pregnant patients carrying the AB blood group in order to prevent the syndrome and improve prognosis.

D-dimer in preeclampsia: systematic review and meta-analysis.

Preeclampsia is a multifactorial disease characterized by high blood pressure and proteinuria after the 20th week of pregnancy. Preeclampsia is associated with microvasculature fibrin deposition and maternal organ dysfunction. D-dimer (D-Di) has been used as a marker of production/degradation of fibrin in vivo. D-Di has emerged as a useful diagnostic tool for thrombotic conditions because its plasma concentration has a high negative predictive value for venous thromboembolism. The aim of this study was to evaluate publications that assessed plasma D-Di in preeclampsia and normotensive pregnant subjects to define its diagnostic value. A total of 194 publications were identified. Following the exclusion process, seven studies were in accordance with the pre-defined eligibility criteria. This systematic review was performed with methodologic accuracy, including a careful definition of preeclampsia and a high sensitivity literature search strategy. Quality of the included studies was assessed in accordance with widely accepted literature recommendations. Our meta-analysis indicates that increased plasma D-Di is associated with preeclampsia in the third trimester of gestation vs normotensive pregnant subjects. These preliminary findings in this select group of patients clearly highlight the need for additional comprehensive studies throughout pregnancy, including the establishment of an appropriate cut-off, in order to fully elucidate the diagnostic/prognostic role of D-Di in preeclampsia.

Heparin pharmacovigilance in Brazil.

OBJECTIVE: To investigate the biological origin of injectable unfractioned heparin available in Brazilian market by discussing the impact of the profile of commercial products and the changes in heparin monograph on the drug safety. METHODS: The Anvisa data base for the Registered Products of Pharmaceutical Companies and the Dictionary of Pharmaceutical Specialties (DEF 2008/2009) were searched. A survey with industries having an active permission for marketing the drug in Brazil was conducted. RESULTS: Five companies were granted a permission to market unfractioned heparin in Brazil. Three of them are porcine in origin and two of them are bovine in origin, with only one explicitly showing this information in the package insert. The effectiveness and safety of heparin studied in non-Brazilian populations may not represent the Brazilian reality, since most countries no longer produce bovine heparin. The currently marketed heparin has approximately 10% less anticoagulant activity than that previously produced and this change may have clinical implications. CONCLUSIONS: Evidence about the lack of dose interchangeability between bovine and porcine heparins and the unique safety profile of these drugs indicates the need to follow the treatment and the patients' response. Events threatening the patient's safety must be reported to the pharmacovigilance system in each particular country.

Farmacovigilância da heparina no Brasil / Heparin pharmacovigilance in Brazil

OBJETIVO: Investigar a origem das preparações de heparina, na forma farmacêutica injetável, disponíveis no mercado brasileiro, discutindo o impacto do perfil dos produtos comercializados e das alterações na monografia da heparina na segurança do fármaco. MÉTODOS: Pesquisou-se o banco de dados de Produtos Registrados das Empresas de Medicamentos da Anvisa e o Dicionário de Especialidades Farmacêuticas (DEF 2008/2009). Foi realizado inquérito com as indústrias com autorização ativa para o comércio do fármaco no Brasil. RESULTADOS: Cinco indústrias possuem autorização para o comércio de heparina não fracionada no Brasil. Três são de origem suína e duas de origem bovina, sendo que apenas uma possui essa informação explicitada na bula. A efetividade e a segurança da heparina, estudadas em populações estrangeiras, podem não representar a nossa realidade, já que a maioria dos países não produz a heparina bovina. A heparina atualmente comercializada tem, ainda, aproximadamente 10 por cento menos atividade anticoagulante que a anteriormente produzida, e essa alteração pode ter implicações clínicas. CONCLUSÃO: Evidências acerca da ausência de intercambialidade de doses entre as heparinas de origem bovina e suína e o diferenciado perfil de segurança entre esses fármacos indicam necessidade de acompanhamento do tratamento e da resposta dos pacientes. Eventos que ameacem a segurança do paciente devem ser comunicados ao sistema da farmacovigilância do país.

OBJECTIVE: To investigate the biological origin of injectable unfractioned heparin available in Brazilian market by discussing the impact of the profile of commercial products and the changes in heparin monograph on the drug safety. METHODS: The Anvisa data base for the Registered Products of Pharmaceutical Companies and the Dictionary of Pharmaceutical Specialties (DEF 2008/2009) were searched. A survey with industries having an active permission for marketing the drug in Brazil was conducted. RESULTS: Five companies were granted a permission to market unfractioned heparin in Brazil. Three of them are porcine in origin and two of them are bovine in origin, with only one explicitly showing this information in the package insert. The effectiveness and safety of heparin studied in non-Brazilian populations may not represent the Brazilian reality, since most countries no longer produce bovine heparin. The currently marketed heparin has approximately 10 percent less anticoagulant activity than that previously produced and this change may have clinical implications. CONCLUSIONS: Evidence about the lack of dose interchangeability between bovine and porcine heparins and the unique safety profile of these drugs indicates the need to follow the treatment and the patients' response. Events threatening the patient's safety must be reported to the pharmacovigilance system in each particular country.

Accuracy of a prediction model for heparin-induced thrombocytopenia (HIT): an analysis based on individual patient data.

BACKGROUND: Heparin-induced thrombocytopenia (HIT) is an adverse drug reaction associated with thrombosis, and its paradoxical nature is a challenging issue for the diagnosis. The '4Ts' scoring system represents a simple and efficient way to improve clinical diagnoses of the syndrome. This system classifies patients as having high, intermediate, and low clinical probability for HIT. However, uncertainty remains concerning its clinical meaning, thus weakening the diagnostic value of this screening instrument. METHODS: We analyzed the diagnostic test accuracy based on individual patient data extracted from published primary scientific studies. This study focused on 186 cases of treatment with heparin, which later evolved into a clinical suspicion of HIT. Upon choosing the most appropriate reference laboratory, the accuracy of the 4Ts was analyzed using the receiver operator characteristic curve analysis. RESULTS: Half of the positive cases (57.1%) were classified as having a high score, while 25.5% of the negative cases were classified as a having low score for HIT. Slightly more than half of all patients (53.2%) were classified as having an intermediate score. As such, the pre-test instrument would most likely fail to distinguish between diseased and nondiseased patients in a relevant number of cases. The calculated accuracy of the summary indicates that the 4Ts can be considered a good, but not a defining, test. CONCLUSION: Further studies are warranted regarding clinical score systems, either alone or in combination with laboratory tests, in an attempt to improve the early diagnosis of this adverse drug reaction and to provide better care for at-risk patients.