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CP-144 Electronic auto-injection device for β-interferon administration in multiple sclerosis patients: a new tool to improve adherence
  1. S Vallinas,
  2. I Loizaga Diaz,
  3. Z Perez España,
  4. A Llona Armada,
  5. MM Alvarez Lavin,
  6. MJ Yurrebaso Ibarretxe
  1. Hospital Universitario Basurto, Pharmacy, Bilbao, Spain


Background Adherence to injectable disease-modifying drugs becomes an imperative to achieve a reduction in the number of relapses and delay disease symptoms in relapsing-remitting multiple sclerosis patients. From our service, we estimate patient adherence by an indirect method, in order to focus our work on patients with adherence problems.

Purpose To find out the relationship between the indirectly-calculated adherence from the Pharmacy service, with the real one measured by a self-injection device (Rebismart) in Multiple Sclerosis patients with ongoing Rebif treatment.

Materials and methods A personal interview was performed with all the 31 patients currently in treatment with Rebif (all doses) in our Hospital. Sex, age, time on treatment with injectable disease-modifying drugs and time on treatment with Rebif were recorded. Indirect adherence was calculated as units dispensed/units needed x 100, and direct adherence was obtained by reading the Rebismart auto-injector device. The two values were compared using Student’s t test for paired samples, and differences were measured by the intraclass correlation coefficient.

Results An intraclass correlation coefficient of 0.75 was obtained, which means that indirect method may be suitable to estimate adherence in our patients cohort. However, the use of this electronic device allowed us to detect some very low-adherence cases, which had not been suspected in the interview. In one case 31.270 € was wasted in two years (the medicine was delivered but the patient never took it).

Conclusions In our cohort of patients, indirectly measured adherence correlates well with the directly measured adherence. Thus, we can use this way of measuring the patient’s adherence in order to focus pharmacist effort on those cases that really need it. However, we cannot forget that low-adherence cases can be underestimated.

No conflict of interest.

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