Relational continuity may give better clinical outcomes in patients with serious mental illness - a systematic review.

Background: Continuity of care is considered important for results of treatment of serious mental illness (SMI). Yet, evidence of associations between relational continuity and different medical and social outcomes is sparse. Research approaches differ considerably regarding how to best assess continuity as well as which outcome to study. It has hitherto been difficult to evaluate the importance of relational continuity of care. The aim of this systematic review was to investigate treatment outcomes, including effects on resource use and costs associated with receiving higher relational continuity of care for patients with SMI.

Methods: Eleven databases were searched between January 2000 and February 2021 for studies investigating associations between some measure of relational continuity and health outcomes and costs. All eligible studies were assessed for study relevance and risk of bias by at least two independent reviewers. Only studies with acceptable risk of bias were included. Due to study heterogeneity the synthesis was made narratively, without meta-analysis. The certainty of the summarized result was assessed using GRADE. Study registration number in PROSPERO: CRD42020196518.

Results: We identified 8 916 unique references and included 17 studies comprising around 300 000 patients in the review. The results were described with regard to seven outcomes. The results indicated that higher relational continuity of care for patients with serious mental illness may prevent premature deaths and suicide, may lower the number of emergency department (ED) visits and may contribute to a better quality of life compared to patients receiving lower levels of relational continuity of care. The certainty of the evidence was assessed as low or very low for all outcomes. The certainty of results for the outcomes hospitalization, costs, symptoms and functioning, and adherence to drug treatment was very low with the result that no reliable conclusions could be drawn in these areas.

Conclusions: The results of this systematic review indicate that having higher relational continuity of care may have beneficial effects for patients with severe mental illness, and no results have indicated the opposite relationship. There is a need for better studies using clear and distinctive measures of exposure for relational continuity of care.