Characterizing high system use across the primary-tertiary care continuum: parallel analyses of select Canadian health datasets

Williamson, T (NPI); McBrien, K; Fabreau, G; Ronksley, PE; Affleck, E; Singer, A; Aubrey-Bassler, K; Natarajan, N; Wong, ST; Barber, D; Manca, D; Garies, S; Chafe, R; Nixon, L; Halas, G; Chan, K; Johnson, D; O’Beirne, M; Drummond, N; Katz, A.


With 5% of patients consuming over 60% of health care resources, a tailored approach to managing high system users may improve patient care and outcomes, while reducing health spending. We aim to better understand the clinical, social, and demographic characteristics of high primary care users and high acute care users.


We performed an observational study to identify patients with a health care encounter between 2010-2015 from electronic medical record data housed by the Canadian Primary Care Sentinel Surveillance Network (CPCSSN). CPCSSN is a nationally representative sample of primary care practices from 8 provinces/territories including more than 1,500,000 patients. Characteristics of interest include: 1) health care utilization, 2) patient demographic factors, and 3) medical complexity, defined as the presence of three or more chronic conditions in three or more body systems.


On average, the top 10% of primary care users had 10 or more encounters per year. Of the total primary care encounters during the study period, 33.6% were attributable to high users in 2010 and 35.4% were attributable to high users by 2015. High primary care users have different reasons for encounters than high acute care users.


High primary care use can be defined as ≥10 encounters in a year. Direct linkage of CPCSSN and acute care use data would inform actionable activities regarding those at highest risk of becoming high users of the acute care system.