[Evaluation of pharmacodynamic target attainment with vancomycin treatment of bacteremia due to Staphylococcus aureus methicillin resistant]. / Evaluación farmacocinética y farmacodinámica del tratamiento con vancomicina en la bacteriemia por Staphylococcusaureus resistente a meticilina.

OBJECTIVE: The objective of the study is to evaluate the ability of standard vancomycin dosing strategies actually recommended to attain the pharmacodynamic target of an area under the curve of vancomycin serum concentration versus time from 0 to 24 hours (AUC(24h)) to minimum inhibitory concentration (MIC) ratio greater than 400:1 for patients with a suspected or documented methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia by individual analysis and Monte Carlo simulation. MATERIAL AND METHODS: The study included all patients admitted with suspected or proven MRSA infection during the years 2007-2008, and who were initially treated with vancomycin at a dose of 30 mg/kg/ day, and underwent pharmacokinetic monitoring. The area under the curve of vancomycin serum concentration versus time from 0 to 24 hours (AUC(24h)) was calculated as daily dose/ clearance total (D(24h)/CL). Additionally, we studied 45 isolates of MRSA obtained from blood cultures in the period 2007-2008. The MIC to vancomycin was determined using Epsilon-test®. The PK-PD parameter calculated was AUC(24h)/MIC. Microsoft Excel was used to perform a 10.000 subject Monte Carlo simulation. An AUC(24h)/MIC > or =400 was assumed as the target attainment. RESULTS: In the individual study, the percentage of patients with AUC(24h)/ MIC(50/90) > or = 400 was 50%. The probability (%) of attaining AUC(24h)/MIC ratio values > or = 400 by Monte Carlo simulation was of 66%. The vancomycin MIC value from which the scenario would have to wait a suboptimal treatment (target < 90%) was >1 mg/ L. DISCUSSION: This study shows that in the population studied to achieve a vancomycin AUC(24h)/MIC > or =400 is not always attained with the standard dose. Therefore, one would expect a high probability of suboptimal vancomycin AUC(24h)/MIC ratios for patients infected with organisms with vancomycin MICs of >1 mg/ L treated with doses of 30 mg/ kg/ day.

Evaluación farmacocinética y farmacodinámica del tratamiento con vancomicina en la bacteriemia por Staphylococcus aureus resistente a meticilina / Evaluation of pharmacodynamic target attainment with vancomycin treatment of bacteremia due to Staphylococcus aureus methicillin resistant

Objetivo: Evaluar la capacidad de la actual estrategia dedosificación de vancomicina de obtener un objetivo farmacocinético/farmacodinámico (FC/FD) de área bajo la curva CMImayor de 400 en pacientes con sospecha o bacteriemia documentadapor Staphylococcus aureus resistente a meticilina(SARM) mediante análisis individual de los pacientes y simulaciónde Monte Carlo.Material y métodos: El estudio incluyó a todos los pacientesingresados con sospecha o bacteriemia documentada porSARM durante los años 2007-2008 y que inicialmente fuerontratados con una dosis de vancomicina de 30 mg/kg/día y quefueron sometidos a seguimiento farmacocinético.El área bajo la curva de la concentración sérica de vancomicinafrente al tiempo de 0 a 24 horas (ABC24h) se calculó comola dosis diaria / aclaramiento total (D24h/CL). Además, se estudiaron45 cepas de SARM obtenidas de hemocultivospertenecientes a pacientes individuales. El CMI a vancomicinafue determinada por Epsilon-test®. Además se realizó una simulaciónde Monte Carlo sobre 10.000 individuos, un ABC24h/CMI >=400 se asumió como objetivo.Resultados: en el estudio individual, el porcentaje de pacientescon ABC24h/CMI50/90 >=400 fue del 50%. La probabilidad(%) de alcanzar ABC24h/CMI >= 400 por simulación Monte Carloen la población estudiada fue de 66%. El valor de CMI a vancomicinaa partir del cual se podría inferir un escenario subóptimode tratamiento (objetivo <90%) fue de > 1 mg/L.Discusión: Este estudio muestra que en la población estudiadaconseguir un cociente ABC24h/CMI >= 400 para vancomicinano es siempre posible con la dosis estándar especialmenteen pacientes infectados con microorganismos con CMI a vancomicina> 1 mg/L y que son tratados con dosis de vancomicinade 30 mg/kg/día(AU)

Objective: The objective of the study is to evaluatethe ability of standard vancomycin dosing strategiesactually recommended to attain the pharmacodynamictarget of an area under the curve of vancomycin serumconcentration versus time from 0 to 24 hours (AUC24h)to minimum inhibitory concentration (MIC) ratio greaterthan 400:1 for patients with a suspected or documentedmethicillin-resistant Staphylococcus aureus(MRSA) bacteraemia by individual analysis and MonteCarlo simulation.Material and methods: The study included all patientsadmitted with suspected or proven MRSA infectionduring the years 2007-2008, and who were initiallytreated with vancomycin at a dose of 30mg/kg/day, and underwent pharmacokinetic monitoring.The area under the curve of vancomycin serumconcentration versus time from 0 to 24 hours (AUC24h)was calculated as daily dose/clearance total (D24h/CL).Additionally, we studied 45 isolates of MRSA obtainedfrom blood cultures in the period 2007-2008. The MICto vancomycin was determined using Epsilon-test®.The PK-PD parameter calculated was AUC24h/MIC. MicrosoftExcel was used to perform a 10.000 subjectMonte Carlo simulation. An AUC24h/MIC ≥ 400 was assumedas the target attainment. Results: In the individual study, the percentage of patientswith AUC24h/MIC50/90 >= 400 was 50%. The probability(%) of attaining AUC24h/MIC ratio values >= 400 by MonteCarlo simulation was of 66%. The vancomycin MIC valuefrom which the scenario would have to wait a suboptimaltreatment (target <90%) was >1 mg/L.Discussion: This study shows that in the populationstudied to achieve a vancomycin AUC24h/MIC >= 400 isnot always attained with the standard dose. Therefore,one would expect a high probability of suboptimal vancomycinAUC24h/MIC ratios for patients infected with organismswith vancomycin MICs of >1 mg/L treated withdoses of 30 mg/kg/day(AU)

[Pharmacological treatment adherence by older patients after hospital discharge]. / Adherencia al tratamiento farmacológico en pacientes ancianos tras el alta hospitalaria.

UNLABELLED: Little information is available on drug adherence in older patients after discharge or on predictors of non-adherence. OBJECTIVES: To determine the rate of treatment adherence and associated factors in elderly patients after hospital discharge with a view to identifying opportunities for improvement. METHOD: We performed a cross-sectional study of 70 patients aged over 65 years old discharged from an internal medicine unit who were self-sufficient regarding treatment management. RESULTS: Only 8.6% of patients complied with the recommended treatment. Eighty-five percent of the drugs were taken incorrectly: 67% were taken in excess, 33% were taken less than prescribed, and 54% were taken without following the recommendations concerning timetable and food intake. The most frequent reasons identified by the patients for not taking the medication correctly were lack of knowledge and forgetfulness. The most frequent risk factors were male gender, living with adult siblings, and taking a large number of prescribed medicines. Information given by the doctor about the treatment and assistance from a friend or relative at home increased adherence. CONCLUSIONS: Treatment adherence after hospital discharge in patients aged over 65 years old is very low. Instruments should be sought to counter forgetfulness and recommendations should be adapted to improve patients' knowledge of prescriptions.