DEprescribing: perceptions of PAtients Living with advanced cancer. A multicentre, prospective mixed observational study.

Polymedication in palliative oncology care is a real public health problem. This phenomenon has been shown to increase the risk of iatrogenesis, reduce patients' quality of life and increase healthcare costs. For many years, health policies have been developed in geriatrics to reduce polymedication through deprescription tools.

Recently, palliative care initiatives have been introduced, but without having studied the potential specificities of this population (younger, with a different care dynamic and life trajectory). It is important to better understand this population's perceptions of deprescribing in order to adapt tools/actions to make these approaches more efficient.

The primary aim of this study is to investigate patients' perceptions of deprescribing in palliative cancer care, and the secondary aim is to investigate factors that may influence patients' attitudes and beliefs about deprescribing. At the same time, we will study the psychometric properties of the rPATD (Revised Patients' Attitudes Towards Deprescribing) in this population (a standardized questionnaire validated in geriatric medicine to assess patients' perceptions of deprescription).An ancillary study will be carried out to investigate the link between patients' health literacy and their perception of deprescribing (health literacy is defined as the ability to acquire, understand and use information in ways that promote and maintain good health).

To meet our objectives, we will conduct a 3-year national, prospective, observational, multicenter study with an exploratory sequential mixed design. The study will comprise an initial qualitative phase. Semi-directed individual interviews using a descriptive approach will be carried out (around 25 patients, over an 8-month period). Following analysis of the qualitative data, we will then carry out a quantitative study to determine the distribution of the different profiles within this population and the factors influencing the perception of deprescription. The self-administered questionnaires, rPATD and BMQ (medication beliefs questionnaire), potentially supplemented by other items following analysis of the qualitative data, will be administered to 300 patients (over a 12-month period).The ancillary study will be carried out during this second phase, using a validated self-questionnaire to assess patients' level of literacy.

Thanks to the different results, we will improve our knowledge of the perception of deprescription in palliative oncology care, in order to develop approaches adapted to the specificities of our population to reduce polymedication and thus improve the quality of life of our patients and reduce the risks of iatrogenia.