Abstract

Background Progressive respiratory muscle weakness in neuromuscular diseases (NMD) impairs cough effectiveness and increases respiratory morbidity. We compared peak cough flow (PCF) and vital capacity (VC) across airway clearance/cough augmentation techniques in adolescents and young adults using home noninvasive ventilation (NIV). Methods In this cross-sectional physiological study, adolescents and young adults with NMD receiving home NIV were evaluated at home. PCF and VC were measured at baseline and immediately after manual assisted cough (MAC), NIV at usual settings, NIV at inspiratory positive airway pressure of 30 cmH2O, air stacking (AS), glossopharyngeal breathing (GPB), and mechanical insufflation-exsufflation (MI-E). Techniques were tested alone and in combination with MAC; the sequence was randomized within participants. Results Twenty-four participants (70.8% male; age 17.5 +/- 2.4 years) were included. Baseline PCF was 211.2 +/- 89.4 L/min. Compared with baseline, PCF increased with MAC, AS, NIV at usual settings, NIV at 30 cmH2O, and MI-E (all p < 0.05), whereas GPB showed no significant change. When combined with MAC, all techniques further increased PCF (e.g., AS + MAC, 306.7 +/- 98.4; NIV-30 + MAC, 297.1 +/- 94.0 L/min; all p < 0.001), with no between-technique differences. VC increased after AS, MI-E, and NIV (all p < 0.005), but not after GPB. Conclusions In adolescents and young adults with NMD using home NIV, AS, NIV, and MI-E improved cough effectiveness and lung volume, and adding MAC produced additional PCF gains.