A clinical frailty scale (CFS) developed at Nova Scotia's Dalhousie University is helping doctors predict outcomes of older COVID-19 patients in urgent care settings and decide who gets more aggressive treatments.
Because the CFS quickly offers a quantitative number, it avoids age bias when it comes to treatment decisions, said Kenneth Rockwood, MD, of the Division of Geriatric Medicine, Department of Community Health and Epidemiology, School of Health Administration, whose team developed the scale.
He said use of the scale could prevent scenarios such as occurred in Italy, where used age as a cut-off for COVID-19 patients who got ventilators. In fact, it's envisioned for that use in the U.K. National Institute for Health and Care Excellence guidelines and the Swiss guidelines for treating COVID-19, he said. Plus, the CFS has been part of routine evaluation in intensive care units for several years in Australia and New Zealand.
"We've seen with COVID-19 that some people over 80 recover, while some who are a decade or so younger don't," Rockwood said.
The CFS is utilized by various hospitals across Canada, and throughout Great Britain's National Health Service for patients in emergency departments and in long-term care settings. The scale has various practical clinical uses including helping to for patients with heart attacks, influenza, broken hips, and other major medical problems. The scale is also used to help plan future care for patients, such as whether patients discharged can go home or need care.
Baseline frailty is what matters, Rockwood emphasized, explaining that many older people with acute illness have non-typical presentations, look confused, immobile, or unable to function as a result of their illness -- yet many are not frail. The CFS, however, reveals those differences. While scores such as and take the severity of an illness into account, they don't show what the person was like at baseline.
The CFS includes multiple factors that affect patient outcome such as comorbid conditions, baseline disabilities and functions, medications, and balance. With COVID-19 the CFS shouldn't be used alone – disease severity must also be taken into account, Rockwood said.
The CFS is a distilled easy-to-use version of the Clinical Frailty index (CFI), and is available as either a wallet-sized card or phone app. Both are available for , and their effectiveness has been validated in multiple studies over the past decade, he said.
The CFI is a computation done using a list of medical problems and disabilities, each of which has a numeric value. Doctors use these values and add up the total. The sum of the complaints is then divided by the total number of fields explained in the instructions, and include factors such as balance and mobility.
A calculation results in a number that indicates the patient's level of frailty. For example, someone who is not frail has a value of 0.15 or under, but as the value approaches 0.7 the prognosis becomes more dire – something demonstrated in a U.K. of 365,000 people, with higher frailty indicating higher morbidity, Rockwood said.
For COVID-19 patients, the CFS is being studied in several hospitals across Canada that are part of the , which collects data about adults hospitalized for influenza. The network is now collecting data on COVID-19 patients, said Melissa Andrew, MD, also in the Division of Geriatric Medicine, Department of Community Health and Epidemiology.
Previous studies showed the CFI was highly accurate in predicting the outcomes of patients over age 65 hospitalized for influenza, Andrew said, noting that a of 5,011 patients admitted to Canadian hospitals where the CFI was used showed that increasing baseline frailty is associated with lower odds of recovery.
The scale is also being used to determine what care elderly residents in long-term care should receive and whether those who get COVID-19 should be moved to hospital, or can be cared for in long-term care.
The U.K.'s National Health Service includes the CFS as part of their , she added.
According to Rade Vukmir, MD, an emergency physician in Pennsylvania, and spokesperson for the American College of Emergency Physicians, emergency physicians often use Clinical Decision Rules. Normally, these algorithms allow for a systematic, predictable approach to diagnosis and treatment, but they have limitations in COVID-19.
He told 鶹ý that although he was not familiar with the CFS, with COVID-19 "numerous specific treatments are being utilized and tested in real time, which means that extrapolating broadly applicable data will continue to be a challenge," he said. The rapid pace of patient presentations, disease progression, and varying levels of resources in any hospital or region means there is no 'one-size-fits-all' approach.
Vukmir added that the COVID-19 Prognostic Tool, which is based on CDC data, helps estimate mortality rates in clinical settings. The Chest CT Severity Score utilizes imaging tools to estimate prognosis with severe cases with lung involvement, and the COVID-19 Severity Index postulates both time course and etiologic and treatment variation throughout the disease course, he explained.
Pippa Wysong is a science and medical writer.