The German health care system is sectorized with health service providers offering a) outpatient treatment and care, b) inpatient treatment and care or c) rehabilitation. While treatment and care within these sectors can be considered to be of high quality, there is a lack of widely available approaches to deliver treatment and care across sectors. Treatment paths for people with chronic diseases or the requirements of elderly people suffering from multimorbidity need frequent transitions between sectors. However, in Germany boundaries of sectors are considered rigid and transitions between sectors are a threat to treatment continuity, which results in inefficient treatment. As this problem has been identified and described by the Advisory Council on the Assessment of Developments in the Health Care System (Sachverständigenrat zur Begutachtung der Entwicklung im Gesundheitswesen) already in 20121, different approaches have been proposed. This study addresses the lack of integrated cross-sectoral approaches to overcome the challenges caused by the sectorized German health care system.There is sound scientific evidence internationally and nationally that collaborative concepts of care can improve treatment and care of people with dementia in primary care (Thyrian et al. 2017). Those concepts are person-centered in the sense of a) taking into account the individual needs, circumstances and priorities, and b) aiming at outcomes relevant to the individuals life, like everyday functionality, (health related) quality of life and social inclusion.

The trial is a complex, longitudinal, multisite randomized controlled trial (intervention vs. care as usual). Recruitment of the study population will be conducted in two participating hospitals. After meeting the eligibility criteria, participants will be asked for written informed consent. With all participants a basic baseline assessment will be conducted (T0) in the hospital. After that they will be randomized in either the intervention group or control group. The intervention group will then receive the intervention, the control group care as usual. Further data assessments will be conducted at all participants´ home 3 months after discharge (T1) and at the participants´ home 12 months after discharge (T2). A process evaluation will also be applied in this study. Data assessment will be conducted by specifically trained study staff. Places of assessment are chosen for the highest possible convenience for the participants. Data assessments will include a) primary data from the participants being assessed, computer-assisted, face-to face and paper-pencil, b) secondary data from patient records in the hospital and from treating physicians.

The main research question of this protocol addresses the effectiveness of Dementia Care Management (DCM) in the intersectoral setting for people with cognitive impairment (PCI) in treatment and care across the in-hospital and primary care sector. The investigators will test the hypothesis if PCI receiving DCM initiated in hospitals and continued after discharge into ambulatory care do have better health and social outcomes after one year than PCI not receiving DCM. The patient-oriented minor hypotheses of this protocol are: ICM improves (a) health related quality of life sustainable, (b) social functioning and integration and (c) adequate treatment and care for dementia and co-morbidities in the ambulatory setting. It reduces (d) the risk for drug related problems in cognitive impairment and comorbidities and (e) the risk for re-admission to the hospital. The intervention prevents (f) incident delirium - given better awareness in respect to precipitating factors. The healthcare provider-oriented minor hypotheses are: ICM (a) reduces re-admission rates and thus saves costs in the inpatient setting. It increases (b) the chances to delay institutionalization significantly and thus saves costs from perspective of statutory health insurance. It (c) improves communication and exchange between treatment and care provider from different health care sectors sustainable. Furthermore, this protocol evaluates the process of implementing ICM along the main research question: How is ICM evaluated and rated among the different groups affected by it? Specific research questions are: What are the perceived benefits for (a) the providers (in the inpatient setting, (b) providers in the ambulatory setting, (c) the PCI and their caregiver? Is ICM evaluated as (d) improving communication and exchange between treatment and care provider from different health care sectors sustainable? And last not least, (e) what are the enablers and barriers to implement ICM in routine care?