About 20% of emergency room admissions among people over the age of 75 are related to medication-induced adverse events. These events are exacerbated by polypharmacy, which can be inappropriate when prescribed medications have an uncertain benefit-risk balance or cause harmful drug interactions. Among potentially inappropriate medications (PIMs), those with anticholinergic and/or sedative properties are the most harmful to older adults and yet are very frequently prescribed. Indeed, in France, 33% of older patients living at home are treated with this type of medication, the use of which is associated with cognitive decline, falls, functional decline (loss of independence), excess mortality, reduced quality of life, and hospitalizations.

Thus, reducing the burden of anticholinergic and sedative medications in older adults is a key priority in the prevention of iatrogenic risk. Among the strategies developed to reduce the use of PIMs in older patients, deprescribing interventions-defined as the supervised discontinuation of inappropriate treatment-have been gradually implemented in recent years. However, few interventional studies on the deprescribing of anticholinergic and/or sedative medications have demonstrated positive results. To better understand the inconsistent effectiveness of deprescribing programs, studies have been conducted to identify the barriers and facilitators of deprescribing, and three key areas have been identified to facilitate the implementation of such programs:

• Involve and support patients in the co-design of the intervention (participatory research) and throughout the intervention itself to reach a shared decision.
• Work in an interdisciplinary manner by combining the areas of expertise of outpatient healthcare professionals regarding patient knowledge and support with the expertise of hospital-based professionals in the field of aging.
• Work in a coordinated manner to foster interprofessional cooperation and ensure the transferability of the deprescribing pathway in real-world settings through multi-professional consultation.

The DIOPAS project aims to develop and implement a multidisciplinary, participatory deprescribing program for older community-dwelling patients being treated by medications with anticholinergic and/or sedative properties. The first step involves the co-development of the intervention, which is the focus of this CC-DIOPAS study. This study proposes a participatory co-development approach to the intervention, bringing together the various types of professionals (from both primary care and hospital) involved in medication optimization, as well as community-dwelling patients and patient partners.

Inclusion Criteria:

• Healthcare Professionals:

In hospitals:

• Geriatricians, hospital pharmacists, or registered nurses;
• Practicing in a geriatric day hospital at the university hospitals in Lyon, Grenoble, Marseille, Nîmes, or Nantes;
• Agree to participate in focus group meetings or the working group.

In primary care facilities:

• General practitioners, community pharmacists, or independent registered nurses;
• Practicing within a primary care facility in the geographic areas served by the university hospitals of Lyon, Grenoble, Marseille, Nîmes, or Nantes;
• Agree to participate in focus group meetings or the working group.

Patients:

Patients of the primary care facilities :

• Patients aged 65 to 80;
• Patients receiving outpatient care (not hospitalized) at a primary care facility within the geographic areas of the University Hospitals of Lyon;
• Patients taking at least 5 chronic medications prescribed per day (polypharmacy);
• Agree to participate in focus group meetings or the working group;

Partner patients:

• Partner patients of the Lyon University Hospital or the RESHAPE laboratory;
• Agree to participate in meetings of the working group or the study's scientific advisory board.

Exclusion Criteria:

• None

• Hospital healthcare professionals involved in geriatric outpatient care and in the medication management of older patients: geriatricians, hospital pharmacists, and nurses
• Primary care healthcare professionals involved in the medication management of the target population: general practitioners, community pharmacists, and private practice nurses
• Patients who met the study's eligibility criteria regarding age and polypharmacy so that the co-designed intervention takes into account their needs and expectations, as well as their opinions regarding the methodology used (participative research). Partner patients will also be solicited.