A combined, tailored pharmacist intervention with dose optimization of phosphate binding drugs to improve phosphate control in patients on dialysis.

In this study we will investigate if a combined, tailored pharmacist intervention including dose optimization will improve phosphate control in hemodialysis patients. We hypothesize that a reduction in phosphate binder pill burden in combination with a combined tailored intervention, taking into account patient preferences, will lead to lower serum phosphate levels, by increasing treatment adherence.

This combined, tailored intervention consists of three visits with patient counselling and two follow-up visits without counselling. In the first visit we will investigate medication adherence, pharmaceutical literacy and patient barriers for the correct use of phosphate binding drugs. We will use several questionnaires (MARS-5: medication adherence rating scale-5, QBS: Quick Barrier Scan, RALPH: Recognizing and Addressing Limited Pharmaceutical literacy). Based on these questionnaires we will select one or more modules of the Tailored Information Guide (TIG).

This Tailored Information Guide consists of five intervention modules (IM): IM1 regards knowledge/information, IM2 addresses forgetfulness, IM3 addresses side effects, IM4 addresses practical problems, and IM5 addresses negative beliefs. The TIG provides an overview of intervention recommendations that pharmacists should use to inform and advise participants to overcome the identified barriers. Information should be provided about hyperphosphatemia, and the use of and need for phosphate binders. Moreover, participants’ representations of hyperphosphatemia and its treatment should be discussed. Interventions recommendations, for instance, include changing medication regime in accordance with the nephrologist, using intake-supporting tools (pill box, medication alarm), registering for pharmacy intake-supporting services or discussing negative medication-related beliefs with the pharmacist.

During the second visit, one to two weeks after the first visit, patient preferences regarding the use of phosphate binding drugs will be discussed, as well as the selected TIG modules. Meanwhile a dose reduction will be carried out, according to a predefined algorithm. Based on all this, a tailored plan will be made using shared-decision making. This plan will be written down and given to the patient and communicated to the treating nephrologist.

The third visit will take place approximately three months after the first visit. During this visit the pharmacist will discuss the patient’s experiences with the treatment plan. If necessary the plan will be adjusted. The MARS-5 will be used to evaluate medication adherence at the end of the intervention.

During the first three visits, patients’ phosphate levels will be managed by the pharmacist. After the third intervention, patients will be returned to usual care.

The fourth and fifth visit will take place approximately six and twelve months after start of the intervention, during which phosphate levels and dose of phosphate binding drugs will be evaluated.

To study the implementation of the intervention, we will also evaluate the implementation fidelity of the intervention. Quantitative and qualitative data will be collected and analysed according to Carrolls’ Conceptual Framework for Implementation Fidelity.

We hypothesize that a reduction in phosphate binder pill burden in combination with a combined tailored intervention, taking into account patient preferences, will lead to lower serum phosphate levels, by increasing treatment adherence.

3 months before and 3, 6 and 12 months after the intervention

The intervention is a dose reduction of phosphate binding therapy in combination with personalized pharmacist-led counselling.