Characterizing the Senior High Cost User (HCU) in Ontario

Characterizing the Senior High Cost User in Ontario: A Population-Based Matched Cohort Study

High cost users (HCUs) are a small group of patients who use a disproportionate amount of health care resources. This study is a retrospective population-based matched cohort analysis of newly incident senior High Cost Users (HCUs) defined as Ontarians aged 66 years or older in the top 5% of healthcare expenditure users in fiscal year 2013 (FY2013). The study objectives are to characterize and contrast Ontario senior HCUs to non-HCUs based on their demographics, co-morbidities, medication use, health service utilization, healthcare expenditures, medication costs and clinical outcomes, and to determine the relative contribution of medications to senior HCUs expenditures

Study Overview

• Status: Unknown
• Conditions: Senior High Cost Users (HCU)
• Intervention / Treatment: Other: HCU Status

Detailed Description

Senior high cost users (HCUs) with annual healthcare expenditures within the top 5% of Ontarians will be identified using established ICES costing algorithms. This cohort will be matched to a cohort of non-HCUs using a 3:1 matching ratio (non-HCU to HCU) based on age at cohort entry (+/- 1 month), sex and geographic location of residence (based on LHIN) for comparative analysis. Descriptive statistics will be used to describe the study populations and outcomes. Regression analyses will be used to adjust for potential confounders when analyzing healthcare resource utilization and costs as a function of HCU status (e.g. income, type of residence, co-morbidities, rural/urban) and/or when analyzing sub-populations [e.g. chronic obstructive pulmonary disease (COPD), congestive heart failure (CHF)]. Logistic regression will be performed using the patient level data to predict the impact of individual factors on the likelihood of becoming a senior HCU.

• Study Type: Observational
• Enrollment (Anticipated): 700000

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 66 years to 105 years (Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Newly incident senior high cost users (HCUs) in Ontario

Description

Inclusion Criteria:

• Ontario residents registered in RPDB between April 1, 2013 - March 31, 2014
• Annual total health care expenditures in FY2013 equal to or greater than financial threshold for the top 5% of all Ontarians

Exclusion Criteria:

• Death on OR prior to index date
• Age > 105
• Annual total health care expenditures in FY2012 fiscal year greater than financial threshold of 5% of all Ontarians in FY2013

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
HCUs; Newly incident seniors with annual total healthcare expenditures in the top 5% of Ontarians	Other: HCU Status; Total healthcare expenditures in the top 5% of Ontarians
Non-HCUs; Seniors with annual total healthcare expenditures below the top 5% of Ontarians

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Total healthcare expenditures per patient	1 year after index date
Total drug costs per patient	1 year after index date
Drug cost to total healthcare expenditure ratio	1 year after index date

Secondary Outcome Measures

Outcome Measure	Time Frame
All-cause mortality	1 year after index date
All-cause hospitalization rate	1 year after index date

Collaborators and Investigators

• Sponsor: McMaster University
• Collaborators: Ontario Drug Policy Research Network (ODPRN); Research Institute of St. Joseph's Hamilton
• Investigators: Principal Investigator: Justin Lee, BScPhm, ACPR, MD, FRCPC, McMaster University

Publications and helpful links

General Publications

• Lee J, Muratov S, Tarride JE, Paterson JM, Thavorn K, Mbuagbaw L, Gomes T, Khuu W, Seow H, Thabane L, Holbrook A. Medication use and its impact on high-cost health care users among older adults: protocol for the population-based matched cohort HiCOSTT study. CMAJ Open. 2021 Jan 11;9(1):E44-E52. doi: 10.9778/cmajo.20190196. Print 2021 Jan-Mar.

Study record dates

Study Major Dates

• Study Start: April 1, 2012
• Primary Completion (Actual): March 1, 2014
• Study Completion (Anticipated): December 1, 2020

Study Registration Dates

• First Submitted: June 24, 2016
• First Submitted That Met QC Criteria: June 24, 2016
• First Posted (Estimate): June 28, 2016

Study Record Updates

• Last Update Posted (Actual): February 5, 2020
• Last Update Submitted That Met QC Criteria: February 4, 2020
• Last Verified: March 1, 2019

More Information

Terms related to this study

• Keywords: Observational study; Multimorbidity; Healthcare utilization; High cost user (HCU); Healthcare expenditures; Medication use; Medication expenditures
• Other Study ID Numbers: 2016 0760 236 000