Background: Inspiratory training using an incentive spirometer (IS) improves respiratory symptoms and functional status in Long COVID. In Taiwan, NRICM101 is commonly used during the acute phase; however, its impact on rehabilitation outcomes remains unclear. Objective: This study evaluated the effects of IS-based respiratory training and the potential influence of prior NRICM101 use. Methods: Participants were grouped by time since recovery, and pre-post changes after six weeks of IS training were compared between those with and without self-reported prior NRICM101 use. Primary outcomes were dyspnea and functional status; secondary outcomes included six-minute walk distance and arterial oxygen content. Results: IS training significantly improved dyspnea (p < 0.0001), functional status (p < 0.0001), and exercise endurance (NRICM101 group: p = 0.002; no NRICM101 group: p < 0.0001). Stratified analysis showed that when initiated within three months of recovery, participants without prior NRICM101 use had greater improvements in dyspnea (p < 0.0001), functional status (p = 0.001), and exercise endurance (p < 0.0001). Conclusions: Prior NRICM101 use may be associated with different rehabilitation patterns, likely reflecting differences in recovery trajectory or patient behavior rather than purely pharmacological effects.
Chen et al. (Tue,) studied this question.