A new scale to help clinicians assess the health-related quality of life of patients with diabetic distal sensorimotor polyneuropathy (DSPN) has been validated in clinical settings, researchers reported.
The Chronic Acquired Polyneuropathy Patient-Reported Index (CAPPRI) demonstrated unidimensionality and performed like an interval-level scale, adequately covering disease severity and addressing relevant life domains, according to Ted Burns, MD, of the University of Virginia in Charlottesville, and colleagues in .
"The key is that it's simple, easy, and practical," Burns told . "It does a nice job conveying what patients might be struggling with. It takes 45 seconds for patients to complete, and it's easy to interpret."
The CAPPRI helps physicians quickly assess how patients are doing between clinic visits. "Time is a commodity and if we can help patients communicate efficiently, we should do that," Burns noted.
"As we start paying attention to more real-world data, rather than just data from clinical trials, we can learn more about how we can best intervene and help," he added.
The CAPPRI assesses 15 disease-specific items that patients with chronic, acquired polyneuropathy -- including those with diabetic DSPN -- might find difficult. The index previously had been validated in immune-mediated polyneuropathy.
For this study, Burns' group recruited investigators with expertise in DSPN from 11 academic sites in the U.S. and Canada. The investigators used CAPPRI in everyday clinical settings at each site from January 2016 to October 2017.
With the CAPPRI questionnaire, patients can communicate the impact of neuropathy-related quality-of-life factors including pain, sleep, psychological well-being, and everyday function. Using a 0 to 2 scale of not at all (0), a little bit (1), or a lot (2), patients rate 15 different statements such as "I have trouble getting dressed because of my neuropathy" or "I am depressed about my neuropathy."
In total, DSPN patients completed a total of 231 CAPPRI scales during clinic visits. The researchers performed conventional and modern psychometric analyses on the completed forms and found that the CAPPRI met Rasch analysis expectations, indicating that it acted like an interval, not just an ordinal, scale.
"The scale has the benefit of being brief and easy to interpret," observed Jessica Robinson-Papp, MD, of Icahn School of Medicine at Mount Sinai in New York City, who was not involved in the study. "It includes all the relevant items that neurologists familiar with the care of patients with diabetic neuropathy would expect to see and would consider important."
The authors performed a rigorous and sophisticated statistical analysis, Robinson-Papp added. "I think that based on this study, the CAPPRI might come to be included in more clinical trials of new treatments for diabetic peripheral neuropathy, especially given the current trends toward greater inclusion of quality-of-life measures in such studies," she told .
Burns and colleagues, who previously have developed and validated an that has been translated into 12 languages and is used in about 20 countries, are making the CAPPRI available to anyone who wants to use it. "The scale is free and in the public domain," Burns said.
A chemotherapy neuropathy patient himself, Burns hopes the CAPPRI will help patients communicate their disease-related problems more effectively. Some patients don't share symptoms unless they are asked, he noted. "The CAPPRI standardizes that and gives patients a little bit of license to tell us how they are doing."
Disclosures
This study had no targeted funding.
Researchers report relationships with CSL Behring, UBC, Octapharma, Baxalta, Grifols, Argenx, Octapharma, Alpha Technologies, Powell Mansfield, BioNevia, DSMB, Alexion, Becton Dickinson, Bioverativ, Genzyme, Aerpio Therapeutics, Strongbridge Pharmaceuticals, OptionCare, Shire, Syntimmune, Marathon, Vertex Pharmaceuticals, GLG, and Clearview Health.
Primary Source
Neurology
Gwathmey K et al "Validation of a simple disease-specific, quality-of-life measure for diabetic polyneuropathy" Neurology 2018; DOI: 10.1212/WNL.0000000000005643.