I found this article simply outstanding. And the approach that the authors detail will be used in other diseases in which quality of life assessment is a critical component of the evaluation of the effectiveness of treatment (in, for example, depression, COPD, and other chronic diseases).
I need to carefully review this article over and over.
In this post, I link to and excerpt from Interpreting the Kansas City Cardiomyopathy Questionnaire in Clinical Trials and Clinical Care: JACC State-of-the-Art Review [PubMed Abstract] [Full-Text HTML] [Full-Text PDF]. J Am Coll Cardiol. 2020 Nov 17;76(20):2379-2390.
All that follows from this awesome resource.
• The KCCQ measures symptoms, physical and social limitations, and quality of life in patients with heart failure.
• In clinical trials, mean differences in KCCQ scores are more difficult to interpret than the proportion of patients experiencing clinically important changes.
• Broader understanding of the meaning of KCCQ scores might encourage greater use of the tool to support patient-centered care.
• Research is needed on how best to integrate the KCCQ into practice and assess its impact on patient care.
To improve the patient-centeredness of care, patient-reported outcomes have been increasingly used to quantify patients’ symptoms, function, and quality of life. In heart failure, the Kansas City Cardiomyopathy Questionnaire (KCCQ) has been qualified by the U.S. Food and Drug Administration as a Clinical Outcome Assessment and recommended as a performance measure for quantifying the quality of care. By systematically asking the same questions reproducibly over time, the KCCQ can validly and sensitively capture the impact of heart failure on patients’ lives and is strongly associated with clinical events over time. This review describes how to interpret the KCCQ, how it should be analyzed in clinical trials to maximize the interpretability of results, and how it can be used in clinical practice and population health. By providing a deeper understanding of the KCCQ, it is hoped that its use can further improve the patient-centeredness of heart failure care.
The primary goals of treating heart failure are to minimize disease progression (death, hospitalization) and to optimize patients’ health status—their symptoms, function, and quality of life. As such, clinical trials focus on these outcomes to establish the evidence base with which to guide patient care. Whereas death and hospitalization are easy to measure, health status can be more difficult to capture in a reliable and valid manner. In the past, this has been most often assessed in trials using the New York Heart Association (NYHA) functional class (1). Whereas NYHA functional class information is simple to collect, it has been shown that health status captured directly from patients is not only a more reliable, sensitive, and valid assessment of the patient’s symptoms and function, but it is also more predictive of heart failure hospitalization and death (2, 3, 4).
Recently, the U.S. Food and Drug Administration (FDA) has endorsed the view that a treatment is potentially approvable based on improving health status alone (5). Moreover, both the cardiovascular drug and device divisions have qualified the Kansas City Cardiomyopathy Questionnaire (KCCQ) as a Clinical Outcome Assessment (6,7), meaning that approval and labeling claims can be obtained by demonstrating clinically important improvements on the KCCQ.
Beyond their role as outcomes in clinical trials, patient-reported health status outcomes also have an important potential role in clinical care (8). As a means of reproducibly asking relevant questions about the frequency and severity of symptoms, the physical and social limitations associated with those symptoms, and patients’ perceptions of the impact of their symptoms and function on their quality of life, the KCCQ performs the role of a “standardized history,” a fundamental component of each clinical encounter.
Overview of the KCCQ
Developed in 1996 and published in 2000 (9), the KCCQ was designed with input from patients and clinicians to capture those domains of how heart failure affects patients’ lives. The KCCQ has a 2-week recall period (given the day-to-day variability in heart failure symptoms) and includes 23 items that map to 7 domains (Central Illustration): symptom frequency; symptom burden; symptom stability; physical limitations; social limitations; quality of life; and self-efficacy (the patient’s understanding of how to manage their heart failure).
To make the KCCQ more feasible to implement in routine clinical care, it was reduced from its original 23 items (KCCQ-23) into a 12-item instrument (KCCQ-12), which includes the symptom frequency, physical limitations, social limitations, and quality of life domains and can also generate the clinical and overall summary scores with excellent concordance to the respective scores of the full instrument (10). Choosing between the 23-item and 12-item versions of the KCCQ depends on the intended use of the instrument. Should the symptom stability or self-efficacy scales be desired, then the 23-item version should be selected, as these are not in the abbreviated questionnaire. In addition, both the drug and device divisions of the FDA have qualified the longer, but not yet the shorter, version of the KCCQ, despite having been provided with identical psychometric data for both forms. Accordingly, clinical trials seeking FDA approval for new treatments may choose the longer version of the KCCQ. In most other circumstances, including routine clinical care, the KCCQ-12 would likely be preferred due to the lower response burden on patients.
Note to myself: Please review the entire article as I found it impossible to summarize as there is no unnecessary detail.