Distinct sensorimotor cough features in a cohort of Progressive Supranuclear Palsy.

Background: Progressive Supranuclear Palsy (PSP) and Parkinson's disease (PD) similarly affect many neural substrates; however, some brain regions may be more impacted by PSP vs PD, giving rise to distinct cough features that could facilitate earlier differential diagnosis and inform airway protection therapies to prevent fatal lung infections, since patients may not effectively sense and clear irritants from their airways. Methods: Thirteen individuals with PSP participated and were age- and sex-matched to persons with PD and healthy, unaffected adults. Using a cross-sectional study design this study aimed to 1) compare cough function in PSP using voluntary and induced reflex cough testing, and 2) compare cough airflow and sensation metrics to PD and healthy adult groups. Results: Voluntary cough function, particularly cough effectiveness during the expiratory phase, was most impaired in the PSP group (P = 0.047), while expiratory phase timing outcomes only differed between PSP and healthy controls (P = 0.03) during reflex cough. There were no significant differences between groups regarding cough sensation to a cough-inducing stimulus (capsaicin), yet there were more cough responders in PSP vs. PD group. Conclusions: Degeneration of distinct neural substrates in PSP versus PD may give rise to differentiating sensorimotor cough deficits. Future directions should focus on cough interventions that maintain respiratory health.