Gastrointestinal dysfunction in Parkinson's disease

Background Gastrointestinal (GI) dysfunction is prevalent in Parkinson's disease (PD). Symptoms are evident throughout the disease course, affect the length of the GI tract and impact on patient quality of life and management. We clarify real-life differences in the frequency and severity of GI symptoms in a cohort of PD and healthy control (HC) subjects. Methods 103 PD patients were compared to 81 HC subjects. Outcome measures collected from validated questionnaires included constipation severity, upper and lower GI symptoms and physical activity. Results PD patients were three-times more likely to experience constipation than HC subjects, (78.6% vs 28.4%), exhibited a fourfold increase in constipation severity and formed harder stools. PD patients also reported increased symptoms of indigestion, nausea, excessive fullness and bloating, compared to the HCs. A higher mean Leeds Dyspepsia Questionnaire score for PD patients (8.3 (standard deviation (SD) 7.7) vs 4.6 (SD 6.1), p = 0.001)) indicated increased symptom severity. Chronic pain was more frequently reported and correlated with constipation and upper GI dysfunction, being more prevalent and severe in women. Physical activity was notably decreased in the PD cohort (1823.6 (+/- 1693.6) vs 2942.4 (+/- 2620.9) metabolic equivalent-minutes/week, p = 0.001) and correlated with constipation severity. PD therapies were associated with increased fullness and bloating and harder stools. Conclusions PD patients report more prevalent and severe GI dysfunction, although our cohort comprised of many later-stage participants. Earlier recognition of GI dysfunction in PD provides the opportunity to direct treatment for chronic pain and constipation, promote physical activity and rationalise PD therapies for optimal patient care.