. Graduate School of Health Sciences, Dokuz Eylül University, Izmir, Turkey.
. Department of Physiotherapy and Rehabilitation, Faculty of Health Sciences, Acıbadem Mehmet Ali Aydınlar University, Istanbul, Turkey.
J Bras Pneumol. 2024 Feb 23;50(1):e20230230. doi: 10.36416/1806-3756/e20230230. eCollection 2024.
This study primarily aimed to investigate the clinical determinants of the Modified Incremental Step Test (MIST) in adults with non-cystic fibrosis bronchiectasis (NCFB). A secondary objective was to compare the cardiopulmonary responses after the MIST and Incremental Shuttle Walk Test (ISWT), two commonly adopted symptom-limited maximum field tests in chronic respiratory diseases.
Forty-six patients with clinically stable bronchiectasis participated in this cross-sectional study. MIST and ISWT were performed to determine exercise capacity, while disease severity, fatigue, and quality of life were assessed using the Bronchiectasis Severity Index (BSI), the Fatigue Severity Scale (FSS), and St. George's Respiratory Questionnaire (SGRQ), respectively. Quadriceps muscle strength was evaluated using a hand-held dynamometer, walking speed with a wireless inertial sensing device, and the level of physical activity (steps/day) with a pedometer.
The BSI score, quadriceps muscle strength, daily step count, and the SGRQ total score explained 61.9% of the variance in the MIST (p < 0.001, R2 = 0.67, AR2 = 0.619). The BSI score (r = -0.412, p = 0.004), quadriceps muscle strength (r = 0.574, p = 0.001), daily step count (r = 0.523, p < 0.001), walking speed (r = 0.402, p = 0.006), FSS score (r = -0.551, p < 0.001), and SGRQ total score (r = -0.570, p < 0.001) correlated with the MIST. The patients achieved higher heart rates (HR), HR%, desaturation, dyspnea, and leg fatigue in the MIST compared to the ISWT (p < 0.05).
Disease severity, quadriceps muscle strength, physical activity level, and quality of life were determinants of MIST. The advantages of the MIST, including higher cardiopulmonary response than ISWT and greater portability, which facilitates its use in various settings, make MIST the preferred choice for investigating symptom-limited exercise capacity in patients with NCFB.
本研究主要旨在探讨非囊性纤维化支气管扩张症（NCFB）成人改良递增台阶试验（MIST）的临床决定因素。次要目的是比较 MIST 和递增穿梭步行试验（ISWT）后的心肺反应，这两种测试都是慢性呼吸系统疾病中常用的症状限制最大场测试。
46 例临床稳定的支气管扩张症患者参与了这项横断面研究。进行 MIST 和 ISWT 以确定运动能力，同时使用支气管扩张严重指数（BSI）、疲劳严重程度量表（FSS）和圣乔治呼吸问卷（SGRQ）分别评估疾病严重程度、疲劳和生活质量。使用手持式测力计评估股四头肌力量，使用无线惯性感应设备测量步行速度，使用计步器测量身体活动水平（步数/天）。
BSI 评分、股四头肌力量、每日步数和 SGRQ 总分解释了 MIST 中 61.9%的变异（p < 0.001，R2 = 0.67，AR2 = 0.619）。BSI 评分（r = -0.412，p = 0.004）、股四头肌力量（r = 0.574，p = 0.001）、每日步数（r = 0.523，p < 0.001）、步行速度（r = 0.402，p = 0.006）、FSS 评分（r = -0.551，p < 0.001）和 SGRQ 总分（r = -0.570，p < 0.001）与 MIST 相关。与 ISWT 相比，患者在 MIST 中达到了更高的心率（HR）、HR%、低氧饱和度、呼吸困难和腿部疲劳（p < 0.05）。
疾病严重程度、股四头肌力量、身体活动水平和生活质量是 MIST 的决定因素。MIST 的优势在于其心肺反应高于 ISWT，并且更便携，这使其在各种环境中都可以使用，因此 MIST 是研究 NCFB 患者症状限制运动能力的首选测试。
