Electronic monitoring of adherence
"Anything that can be measured can be managed"
Electronic monitoring is a method for compiling drug dosing histories in ambulatory patients. It is done by integrating a small microcircuit into drug packages, in such a way that microcircuit records the time and date whenever it detects the maneuvers being made that are needed to remove a dose of drug from the package. The formal technical term is “medication event monitoring”. The ‘event’ refers to one or more things that have to occur in order for a dose to be removed from the package. For solid dosage forms – tablets or capsules – the medication events are removal of the closure, followed by replacement of the closure. The MEMS® monitors record both times, and are capable of storing up to 3800 medication events.
The gold-standard test of the reliability of medication-event monitoring
Obviously opening and closing of the package is an indirect measure of medication-taking, so the question naturally arises about the reliability of the medication event as an indicator that the prescribed dose was actually taken. That question has been tested in a variety of ways, the most demanding of which has been to use the time of medication events to project, with suitable pharmacokinetic models, the time-course of drug concentration in the patient’s plasma, on the assumption that each medication event signified that the patient took the prescribed dose at the time of package opening. At various times in the year-long study, blood was drawn from each patient for direct chemical measurement of drug concentration in plasma. Throughout the year-long study, there was close correspondence between MEMS-projected and directly measured concentrations of drug in plasma. The ability to use dosing history data to project reliably the continuous course of drug concentration in plasma is the gold-standard test of any method that purports to compile drug dosing histories in ambulatory patients.
Long and diverse record of use of MEMS monitors in many settings
As of April, 2008, there were 430 peer-reviewed publications describing results of clinical studies in which AARDEX customers used MEMS monitors to compile drug dosing histories and assess compliance in patients in a wide variety of clinical situations. It represents above 400000 MEMS monitors having been put into use by patients in every continent.
