Healthcare utilization patterns before and after a long COVID diagnosis: a case-control study

Area of Science:

• Public Health
• Epidemiology
• Health Services Research

Background:

• Challenges in Long COVID documentation due to data limitations and diagnostic uncertainty.
• Need for population-level data to understand Long COVID healthcare utilization.
• Lack of clarity on Long COVID patient characteristics and temporal healthcare patterns.

Purpose of the Study:

• To examine characteristics of Long COVID patients.
• To analyze healthcare utilization patterns pre- and post-Long COVID diagnosis.
• To compare Long COVID patients with matched controls.

Main Methods:

• Retrospective, longitudinal case-control study using Colorado's All-Payer Claims Database.
• Inclusion of individuals aged 18+ diagnosed with Long COVID (ICD-10 U09.9) between Oct 2021-Aug 2022.
• Matched 1:2 Long COVID cases to controls based on demographics and enrollment period, with one year pre/post-diagnosis follow-up.

Main Results:

• Identified 12,698 Long COVID patients (prevalence 674/100,000) with continuous enrollment.
• Pre-diagnosis: 17% hospitalized, 40% ED visits.
• Post-diagnosis: Decreased acute care (-6.1% hospitalization, -7.7% ED visits) but increased outpatient visits (+3.6% office, +4.7% specialist) and new medications (+5.2).

Conclusions:

• Long COVID diagnosis is associated with a shift from acute to outpatient healthcare utilization.
• This change indicates potential for improved patient management following diagnosis.
• High healthcare utilization underscores the need for understanding Long COVID's impact on health systems.