Main idea: the recent study proved that Parkinson’s disease affects the respiratory system through the neuromuscular system. The patients have impaired respiratory capacities that are related to the Parkinson’s disease severity, which can be used in diagnostics and respiratory conditions treatment.
Parkinson’s disease affects the neuromuscular system producing a loss of muscle strength that can influence the respiratory system. No study to date has systematically reviewed the existing data on respiratory impairment in PD patients. The aim of this study is to examine the available literature related to respiratory impairment in PD patients. We searched Pubmed, Cinhal, SciELO, and Cochrane Library, from inception until August 2018. The main variables assessed were forced vital capacity percent predicted and forced expiratory volume in 1 s percent predicted. Six studies were included in this systematic review and meta-analysis. The results concluded that PD patients present poorer pulmonary function when compared to healthy controls. When PD patients were compared between ON and OFF states, the results reviewed are in favor of the ON state. We conclude that PD patients have impaired respiratory capacities that are related to the PD severity, time since diagnosis, and OFF state. Adequate follow-up of the respiratory function and studies focused on PD phenotypes have to be considered in future studies.