The Impact of Interpersonal Continuity of Primary Care on Health Care Costs and Use: A Critical Review

Context: Interpersonal continuity is one of the four “C’s” thought to explain primary care’s salutary effects. The last 20 years have witnessed radical shifts in health information technology and a pivot away from continuity as patient-centered medical homes have emphasized open-access scheduling. Further, growth in the number and proportion of insured patients, spurred on by the Patient Protection and Affordable Care Act (ACA) and the Medicare Access and CHIP Reauthorization Act (MACRA), have driven movement toward measure-driven, value-based payment models. The impact these shifts have had on continuity, and in turn continuity’s impact on healthcare costs and utilization, are unclear.

Objective: We synthesized the last 20 years of peer-reviewed evidence on the relationship between continuity & healthcare costs and use, information critical to assessing the need for continuity measurement in value-based payment design.

Study Design and Analysis: This scoping review sought any articles addressing continuity in a primary care setting between 2002 and 2022.

Setting or Dataset: PubMed, Embase, and Scopus.

Population Studied: Primary care patients.

Intervention/Instrument: Guided by a medical librarian & search strategy, we established content domain and comprehensively reviewed the databases for relevant papers, crafted a novel outcome typology and analyzed each paper’s outcomes related to continuity.

Outcome Measures: Search terms included “continuity of care” and “continuity of patient care,” and payor-relevant outcomes, including “cost of care”, “health care costs”, “total cost of care”, “utilization”, “ambulatory care–sensitive conditions”, and hospitalizations for these conditions. Our search was limited to primary care.

Results: Between 2002-2022, we found 18 studies with 18 unique outcomes that examined the association between continuity and healthcare costs, and 79 studies with 142 unique outcomes assessed the association between continuity and desirable healthcare use. Interpersonal continuity was associated with significantly lower costs or more favorable use for 109 of the 160 outcomes.

Conclusions: Interpersonal continuity remains significantly associated with lower healthcare costs and desirable healthcare use. Further disaggregation of these associations at the clinician, team, practice, and system levels will help policymakers and payors understand how best to design value-based payment for primary care that supports continuous relationships.