The effect of subthalamic deep brain stimulation on gastric motility in Parkinson's disease

Deep brain stimulation of the subthalamic nucleus (STN-DBS) is well established for treating the motor symptoms for advanced Parkinson's disease (PD) but its effects on gastric myoelectrical activity and gastrointestinal symptoms have not been well studied. The aim of this study was to evaluate the effect of STN-DBS on gastric motility using electrogastrography (EGG).Twenty patients with PD (5 females, 15 males; mean aged 58.0 ± 9.0 years) who underwent STN-DBS were studied. EGG was performed in fasting and postprandial conditions before STN-DBS and 3 months after the surgery. We also evaluated the frequency and severity of gastrointestinal symptoms based on a structured gastrointestinal dysfunction questionnaire.After STN-DBS the percentage of normogastria (47.8 ± 20.7 vs 51.3 ± 15.1) and period dominant power (PDP) (11.8 ± 1.2 vs 12.3 ± 0.9) significantly increased, the percentage of arrhythmia decreased compared to the baseline during fasting and postprandial state. Abnormal response to a meal (power ratio of PDP1 after meal) decreased from 70% to 55% after 3 months follow-up. The abnormal EGG (the percentage of normogastria70%) decreased in both fasting (from 80% to 65% patients) and postprandial state (from 80% to 60% patients), respectively after the surgery. The most common GI symptoms reported prior to the surgery were constipation 95%, difficulty with defecation 85% and dysphagia 50%. After STN-DBS all gastrointestinal symptoms improved, the greatest improvement was observed in difficulty with defecation.Our results suggest that STN-DBS improves gastric motility as well as gastrointestinal symptoms in PD. Further studies of gastrointestinal motility in PD are warranted.