Impact of Acute Respiratory Failure on S³-NIV Scores in Patients Treated With Home Noninvasive Ventilation

Introduction

The S³-NIV questionnaire is a simple and reliable 11-item tool for the routine assessment of important patient-reported outcomes in patients treated with home noninvasive ventilation (NIV). It provides a total score (11 items) and 2 sub-scores, which cover respiratory symptoms (6 items) and sleep, and adverse effects of NIV (5 items).¹ Lower scores correspond to a higher degree of discomfort. The S³-NIV questionnaire can be completed in 3 to 4 min, which is an advantage over longer health status questionnaires, such as the Severe Respiratory Insufficiency questionnaire² or the Maugeri Foundation Questionnaire.³ The S³-NIV questionnaire is suggested as a useful and valid patient-centered outcome measure and may be a promising tool for home NIV follow-up.⁴

The minimal clinically important difference is the smallest change in score that is perceived by patients as significantly beneficial or detrimental. When caring for patients using home NIV, the minimal clinically important difference is necessary to interpret the clinical impact of changes in the S³-NIV score (ΔS³-NIV) in situations such as a routine modification of NIV settings during follow-up of stable ambulatory patients or acute symptoms corresponding to an episode of respiratory failure requiring hospital admission. How these opposing scenarios affect ΔS³-NIV scores is still unknown. Assessing ΔS³-NIV questionnaire scores in these 2 clinical scenarios is important for clinical management. Also, providing a first estimate of the S³-NIV questionnaire score minimal clinically important difference is required for sample size calculation in future trials that use this tool as an outcome.