Mapping frailty concepts to SNOMED CT

Frailty is considered an emerging syndrome characterized by a decrease in physiological ability to respond to stressors, leading to increased morbidity and mortality rates. Frailty is distinguished from normal age-associated decline because it is a sharp and often rapid decline rather than a gradual slowing down of general functioning. The comprehensive geriatric assessment is currently considered the gold standard for identifying frailty in older adults. The electronic version of this tool is called the eCGA and is commonly included in electronic medical records (EMR) in primary care settings.

We explored the adequacy of SNOMED CT to represent frailty concepts by addressing three research questions: 1) What are the defining characteristics of frailty most commonly used in frailty assessment tools? 2) Are these characteristics captured within one or many frailty assessment tools? 3) Which data elements from existing tool(s) can be reliably mapped to existing SNOMED CT terms?

We conducted a literature search to explore the defining characteristics of frailty and the most commonly used assessment tools. We compared these findings to the components of frailty captured within the eCGA. We then used a descriptive study design to manually map concepts from the eCGA to SNOMED CT.

Our literature review demonstrated that the eCGA contains all common defining characteristics of frailty. Unique assessment questions from the eCGA (n = 133) were manually mapped to SNOMED CT, using expert consensus. Of these, 72 % were direct matches, 17 % were one-to-many matches, and the remaining 11 % were non-matches. Two rounds of expert clinician mapping occurred; inter-rater reliability between the two clinicians was 0.75 (kappa).

The resulting list of mapped eCGA elements to SNOMED CT terms can inform revisions to existing chronic disease databases to include frailty monitoring and surveillance.