The mechanism of action of bronchial thermoplasty (BT) treatment for patients with severe asthma is incompletely understood. This study investigated the 2.5-year impact of BT on airway smooth muscle (ASM) mass and clinical parameters by paired data analysis in 22 patients. Our findings demonstrate the persistence of ASM mass reduction of >50% after 2.5 years. Furthermore, sustained improvement in asthma control, quality of life and exacerbation rates was found, which is in line with previous reports. An association was found between the remaining ASM and both the exacerbation rate (r=0.61, p=0.04 for desmin, r=0.85, p<0.01 for alpha smooth muscle actin (SMA)) and post-bronchodilator forced expiratory volume in 1 s predicted percentage (r=−0.69, p=0.03 for desmin, r=−0.58, p=0.08 for alpha SMA). This study provides new insight into the long-term impact of BT.

中文翻译：

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重症哮喘支气管热成形术后气道平滑肌和长期临床疗效

支气管热成形术（BT）治疗严重哮喘患者的作用机制尚不完全清楚。本研究通过 22 名患者的配对数据分析，调查了 BT 对气道平滑肌 (ASM) 质量和临床参数的 2.5 年影响。我们的研究结果表明，2.5 年后 ASM 质量持续减少超过 50%。此外，哮喘控制、生活质量和恶化率持续改善，这与之前的报告一致。发现剩余 ASM 与恶化率（结蛋白 r=0.61，p=0.04，α 平滑肌肌动蛋白 (SMA) r=0.85，p<0.01）和支气管扩张剂后 1 秒用力呼气量之间存在关联预测百分比（对于 desmin，r=-0.69，p=0.03，对于 alpha SMA，r=-0.58，p=0.08）。这项研究为了解 BT 的长期影响提供了新的见解。