Comparison of dysphagia before and after deep brain stimulation in Parkinson's disease

Although dysphagia is a common problem for many Parkinson's disease (PD) patients, the effect of deep brain stimulation (DBS) on swallowing is unclear. Fourteen subjects with advanced PD underwent videofluorographic swallowing studies prior to bilateral DBS of the subthalamic nucleus (STN) and at 3 and 12 months postprocedure. They were tested under several stimulation and medication conditions. Subjects completed the Dysphagia Handicap Index at each time. There was a strong trend toward improved swallowing response for solid intake in the medication‐free condition with the stimulator on compared with the stimulator off (P = .0107). Also, there was a trend toward improved oral preparation of thin liquids (P = .0368) in the medication‐free condition when the stimulator was on versus off 12 months later. The remaining swallowing parameters showed no change or worsening of swallowing function regardless of stimulator or medication status. Results of the Dysphagia Handicap Index revealed significant improvement in subject self‐perception of swallowing 3 and 12 months following the procedure compared with baseline on the functional subscale (P = .020 and P = .010, respectively), the emotional subscale (P = .013 and P = .003, respectively), and the total score (P = .025 and P = .003, respectively). These data suggest that bilateral STN‐DBS does not substantively impair swallowing in PD. In addition, it may improve motor sequencing of the oropharyngeal swallow for solid consistencies (which are known to provide increased sensory feedback to assist motor planning of the oropharyngeal swallow). Subjects with advanced PD who are undergoing DBS may perceive significant improvement in swallowing ability despite the lack of objective improvements in swallowing function. © 2012 Movement Disorder Society     

Simple clinical tests may predict severe oropharyngeal dysphagia in Parkinson's disease.

OBJECTIVE: To determine if simple screening tests can predict severe oropharyngeal dysphagia in subjects with Parkinson's disease. METHODOLOGY: Forty-five subjects (26 females) of average age 75 (range: 65-94) who were classified as Modified Hoehn and Yahr stages 2 to 5 were enrolled. The presence of oropharyngeal dysphagia was assessed by a symptom questionnaire, 50 ml water swallowing test and videofluroscopic swallowing study. RESULTS: Six of the subjects had severe oropharyngeal dysphagia in videofluroscopic swallowing study. Subsequent multivariate analysis showed that 3 factors could independently predict severe oropharyngeal dysphagia. These included higher Modified Hoehn and Yahr stage (P = 0.042), low Body mass index (P = 0.014), and increased difficulty in keeping food or drink in the mouth (P = 0.047). The regression model had a positive predictive power of 96% (sensitivity: 83.3%, specificity: 97.4%). CONCLUSION: A combination of 3 simple clinical parameters may be useful for screening for severe oropharyngeal dysphagia as shown radiologically in subjects with Parkinson's disease.     

Association of Parkinson's disease with hospitalization for traumatic brain injury

Purpose: The goal of our study was to determine if patients with Parkinson's disease (PD) are more susceptible to hospitalization for traumatic brain injury (TBI). Methods: The US Nationwide Inpatient Sample database was queried (2004–2011) to identify cohorts of patients with PD (N = 1?047?656) and without PD (N = 115?95?173). The age range of the study population was 60–89 years. The incidence of TBI among patients with PD was compared to the incidence of TBI in patients without PD. A multivariate logistic regression model, adjusted for all covariates that significantly differed in the bivariate analyses, was used to determine if PD was an independent predictor of TBI hospitalization. Results: The incidence of TBI hospitalization was significantly higher (relative risk: 1.76, 95% CI: 1.73–1.80) in the PD cohort. The PD cohort with TBI had fewer comorbidities and risk factors for falls/TBI compared to the non-PD cohort with TBI. The multivariable analysis, adjusting for other TBI risk factors, revealed that PD status increased the likelihood of TBI hospitalization (odds ratio: 2.99, 95% CI: 2.93–3.05). Conclusion: Our study shows that patients with PD are more susceptible to hospitalization for TBI. A greater proportion of fall-related TBI occurs in patients with PD compared to patients without PD. Further research is needed to prevent falls in PD patients to avoid TBI.     

Association of homocysteine with ventricular dilatation and brain atrophy in Parkinson's disease

Parkinson's disease (PD) patients are treated with levodopa (l ‐dopa) to help stabilize their impaired motor abilities; however, l ‐dopa leads to increased homocysteine (Hcy) levels, which may have a deleterious effect on brain structure and function. The purpose of this study was to examine the impact of increased Hcy concentration on global brain atrophy as determined by magnetic resonance imaging in PD patients and controls. The effect of high Hcy level on ventricular dilatation (percentage of intracranial volume [%ICV]) and total tissue volume (%ICV) was examined at baseline and longitudinally at 36 months. Age, sex, education, and l ‐dopa duration (in PD patients) were included as covariates. Elevated Hcy levels correlated positively with ventricular dilatation (%ICV) in the whole sample (P = 0.004) and in the PD group (P = 0.008). At baseline, adults with a high Hcy level (>14 μmol/L) had higher ventricular volume (%ICV) than adults with a low Hcy level (≤14 μmol/L) in the whole sample (P = 0.006) and in the PD group (P = 0.03), which persisted over 36 months in both the whole sample (P = 0.004) and the PD group (P = 0.03). PD patients with high Hcy concentrations had a greater rate of ventricular enlargement (%ICV) over time compared with those with low Hcy concentration (P = 0.02). Elevated Hcy concentration was associated with increased ventricular dilatation (%ICV) in PD patients. A larger sample with a broader age range and longer follow‐up is needed to establish the consequences of high Hcy level, including interactions with genetic and environmental risk factors, in PD. © 2014 International Parkinson and Movement Disorder Society     

Freezing of gait in Parkinson's disease is associated with altered functional brain connectivity

BackgroundPatients with Parkinson's disease (PD) may develop several gait disturbances during the course of illness and Freezing of gait (FOG) is one of them. Several neuroimaging studies have been conducted to identify the neural correlates of FOG but results have not been uniform. Resting state functional MRI (rs-fMRI) is relatively less explored in PD patients with FOG. This study aims to compare the whole brain resting state connectivity of PD patients with and without FOG using rs-fMRI.Methodsrs-fMRI was obtained for 28 PD patients (15 with and 13 patients without FOG) who were matched for various demographic and clinical characteristics. Seed to voxel analysis was performed at whole brain level and compared between the two groups.ResultsWhen compared to patients without FOG, the patients with FOG had reduced functional connectivity across multiple seeds. Major finding was reduced inter-hemispheric connectivity of left parietal opercular cortex with multiple regions of the brain primarily involving the primary somatosensory and auditory areas, which also negatively correlated with the FOGQ scores.ConclusionOur findings suggest that alterations in the resting state functional connectivity of the opercular parietal cortex may be one of the substrates of FOG. Reduced interhemispheric connectivity probably is the reason for impairment of control and coordination in bilateral leg movements while walking.     

Fatigue in Parkinson's disease: The contribution of cerebral metabolic changes

Fatigue is a common and disabling non‐motor symptom in Parkinson's disease associated with a feeling of overwhelming lack of energy. The aim of this study was to identify the neural substrates that may contribute to the development of fatigue in Parkinson's disease. Twenty‐three Parkinson's disease patients meeting UK Brain Bank criteria for the diagnosis of idiopathic Parkinson's disease were recruited and completed the 2‐[¹⁸F]fluoro‐2‐deoxy‐D‐glucose (FDG)‐PET scan. The metabolic activities of Parkinson's disease patients with fatigue were compared to those without fatigue using statistical parametric mapping analysis. The Parkinson's disease group exhibiting higher level of fatigue showed anti‐correlated metabolic changes in cortical regions associated with the salience (i.e., right insular region) and default (i.e., bilateral posterior cingulate cortex) networks. The metabolic abnormalities detected in these brain regions displayed a significant correlation with level of fatigue and were associated with a disruption of the functional correlations with different cortical areas. These observations suggest that fatigue in Parkinson's disease may be the expression of metabolic abnormalities and impaired functional interactions between brain regions linked to the salience network and other neural networks. Hum Brain Mapp 38:283–292, 2017. © 2016 Wiley Periodicals, Inc.     

Pathophysiology of diurnal drooling in Parkinson's disease

Drooling is an incapacitating feature of Parkinson's disease. Better pathophysiological insights are needed to improve treatment. In this study, we tested the hypothesis that the cause of drooling is multifactorial. We examined 15 patients with Parkinson's disease with distinct diurnal saliva loss (“droolers”) and 15 patients with Parkinson's disease without drooling complaints (“nondroolers”). We evaluated all factors that could potentially contribute to drooling: swallowing capacity (maximum volume), functional swallowing (assessed with the dysphagia subscale of the Therapy Outcome Measures for rehabilitation specialists), unintentional mouth opening due to hypomimia (Unified Parkinson's Disease Rating Scale item), posture (quantified from sagittal photographs), and nose‐breathing ability. We also quantified the frequency of spontaneous swallowing during 45 minutes of quiet sitting, using polygraphy. Droolers had more advanced Parkinson's disease than nondroolers (Unified Parkinson's Disease Rating Scale motor score 31 vs 22; P = .014). Droolers also scored significantly worse on all recorded variables except for nose breathing. Swallowing frequency tended to be higher, possibly to compensate for less efficient swallowing. Logistic regression with adjustment for age and disease severity showed that hypomimia correlated best with drooling. Linear regression with hypomimia as the dependent variable identified disease severity, dysphagia, and male sex as significant explanatory factors. Drooling in Parkinson's disease results from multiple risk factors, with hypomimia being the most prominent. When monitored, patients appear to compensate by increasing their swallowing frequency, much like the increased cadence that is used to compensate for stepping akinesia. These findings can provide a rationale for behavioral approaches to treat drooling. © 2011 Movement Disorder Society     

The prevalence and patterns of pharyngoesophageal dysmotility in patients with early stage Parkinson's disease

Dysphagia occurs in the majority of patients with Parkinson's disease (PD) and is known to correlate with abnormalities of oropharyngeal function. The aim of this study was to evaluate pharyngoesophageal activity in patients with early‐stage PD. Newly diagnosed PD patients with a symptom duration not exceeding 3 years were included. All PD patients were questioned about symptoms of dysphagia and underwent combined multichannel intraluminal impedance manometry and multiple rapid swallow tests. Fifty‐four patients (22 men and 32 women, 67.1 ± 10.3 years) were enrolled. The duration of Parkinsonian motor symptoms was 11.5 ± 8.8 months, the Hoehn and Yahr stage was 1.6 ± 0.4, and the total Unified Parkinson's Disease Rating Scale was 25.1 ± 18.6. Esophageal manometry in the liquid swallow and viscous swallow tests was abnormal in 22 (40.7%) and 31 (67.4%) patients, respectively. Although manometric abnormalities were more common in patients with more severe dysphagia symptoms, many patients with no or minimal symptoms also had manometric abnormalities. Repetitive deglutition significantly correlated with failed peristalsis and incomplete bolus transit. Abnormal responses to multiple rapid swallow tests were found in 33 out of 54 patients; 29 with incomplete inhibition (repetitive contraction) and 4 with failed peristalsis. These results suggest that the majority of patients with early‐stage PD showed pharyngeal and esophageal dysfunction even before clinical manifestations of dysphagia, which may reflect selective involvement of either the brain stem or the esophageal myenteric plexus in early‐stage PD. © 2010 Movement Disorder Society.     

Transcranial brain sonography in Parkinson's disease with restless legs syndrome

Substantia nigra (SN) hyperechogenicity assessed by transcranial brain sonography (TCS) is a characteristic finding in idiopathic Parkinson's disease (PD). In contrast, SN hypoechogenicity on TCS has been recently demonstrated in restless legs syndrome (RLS). RLS is one of the most common sleep problems in PD, but the pathophysiologic relationship between these two disorders has not been thoroughly elucidated. We compared the SN echogenicities of PD patients with and without RLS to investigate whether comorbid RLS in PD affects SN echogenicity and to explain the echogenic differences between idiopathic RLS (iRLS) and secondary PD–related RLS (pRLS). Sixty‐three PD patients (median age 64.6 ± 10.6 years), 40 iRLS patients (53.1 ± 11.7 years), and 40 healthy controls (69.1 ± 2.3 years) were enrolled in our study. All subjects answered a sleep questionnaire and underwent TCS. PD patients were subdivided into two groups, PD with RLS (PD+RLS, n = 26) and PD without RLS (PD‐RLS, n = 37), and the sonographic findings of each group were compared. Although significant hyperechogenicity was detected in both the SN and SN/midbrain ratios in both PD subgroups compared with the controls and the iRLS group (P < 0.001), there were no significant differences in SN echogenicity between the PD+RLS and PD‐RLS groups. Meanwhile, iRLS patients showed significant SN hypoechogenicity. In conclusion, comorbid RLS in PD did not have an impact on the sonographic SN findings. These results suggest that the pathogenesis of pRLS and iRLS involve different mechanisms. Further study will be required to clarify the association between RLS and PD. © 2010 Movement Disorder Society     

Body weight gain rate in patients with Parkinson's disease and deep brain stimulation.

We evaluated body weight changes in patients with Parkinson's disease (PD) after electrode implantation for deep brain stimulation (DBS) in the subthalamic nucleus (STN) in relation to clinical improvement. Thirty PD patients who received STN DBS were included (22 men, 8 women; mean age, 60.0 +/- 7.1 years; mean PD duration, 13.5 +/- 3.7 years; mean body mass index [BMI], 21.6 +/- 3.0 kg/m2). Body weight, physical activity, and Unified Parkinson's Disease Rating Scale (UPDRS) scores were noted before and 3 and 12 months after the procedure. Significant weight gain occurred in 29 patients; the mean increase was 14.8 +/- 9.8% of initial body weight in 1 year. Of the patients, 46.5% reported weight gain in the first 3 months, 21.4% gradual weight gain in the first 6 months, and 32.1% a slow increase for 1 year. Mean BMI increased up to 24.7 +/- 3.7 kg/m2. After 1 year, mean UPDRS motor score improved significantly in off and in on; and therapy complications improved by 91.0 +/- 17.0%. BMI changes at 3 and 12 months were significantly correlated to dyskinesia score changes, and levodopa dosage was not. In PD, STN DBS produces not only symptom control, but also weight gain. DBS candidates should be given nutritional counseling before the intervention to prevent rapid and/or excessive weight gain.     

OFF-off rebound dyskinesia in subthalamic nucleus deep brain stimulation of Parkinson's disease.

A 61-year-old man with Parkinson's disease (PD), motor fluctuations, and dyskinesias underwent bilateral implantation of deep brain stimulation (DBS) electrodes in the subthalamic nucleus (STN). One month after surgery, DBS was optimized to bilateral monopolar settings at the most proximal electrode just superior to the STN, which improved motor fluctuations and dyskinesias. At several postoperative evaluations off medications overnight, both stimulators were turned off and within 60 seconds he developed severe dyskinesias. When the stimulators were turned back on, the dyskinesias soon resolved. This article is a first report of a unique pattern of rebound-type dyskinesia that occurred in the off medication state produced by stopping STN DBS.     

Contrast sensitivity in Parkinson's disease patients with subthalamic nucleus deep brain stimulation

This study examined whether deep brain stimulation (DBS) would affect the contrast sensitivity (CS) curve in patients with PD. CS was tested in 12 nondemented PD patients treated with bilateral subthalamic nucleus DBS on and off stimulation and medications. Neither stimulation condition (on vs. off) nor medications altered CS performance in this group of patients. However, collapsed across conditions, patients with bipolar stimulation in this study had significantly poorer CS at higher spatial frequencies (12 and 18 cycles per degree) than patients with monopolar stimulation. This suggests that CS deficits in PD may possibly be influenced by DBS polarity and merits further study. © 2009 Movement Disorder Society     

The impact of STN deep brain stimulation on speech in individuals with Parkinson's disease: The patient's perspective

BackgroundSpeech disturbance is highly prevalent and disabling for individuals with Parkinson's disease (PD). Deep brain stimulation (DBS) has been found to adversely impact speech in a number of individuals with PD. This study investigated the differential speech profiles between individuals with PD with and without DBS from the patient's perspective.MethodsA cross sectional research design was used. A total of 758 individuals with PD participated in this study, including 287 individuals with DBS and 471 individuals without DBS. Participants completed the Voice Handicap Index (VHI) and additional questions regarding speech symptoms and the impact of speech on social interaction.ResultsIndependent of age and disease duration, there were statistically significant differences in perceived speech disturbance severity between the STN-DBS group and Non-DBS group, with the DBS group reporting more severe symptoms as well as more significant symptom interference with social interaction and with daily experiences encountered relating to functional, physical, and emotional issues of a voice disorder (VHI). Low volume was the “most common” speech symptom for all individuals with PD patients across both age (younger and older) and disease duration (6–10 years and 11+ years) cohorts. DBS had the greatest adverse impact on “slurred speech.”ConclusionDBS therapy's contribution to speech disturbance is gaining more attention, and the speech symptoms ensuing from and/or being exacerbated by DBS are in the incipient stages of being investigated. Implications for DBS therapy on perceived quality of life are discussed.     

Gender differences in patients with Parkinson's disease treated with subthalamic deep brain stimulation.

We investigated gender-differences in clinical phenomenology and response to deep brain stimulation (DBS) of the subthalamic nucleus (STN) in a group of patients with advanced Parkinson's disease (PD). Thirty-eight consecutive patients with PD (22 men and 16 women), bilaterally implanted for DBS of the STN, were evaluated 1 month before and 11 to 14 months after surgery. Gender differences in severity of the disease (HY and UPDRS), ability in the activities of daily living (ADL, UPDRS II), tremor and rigidity (UPDRS III), bradykinesia (UPDRS III and hand tapping test), levodopa-induced dyskinesias (LIDs, UPDRS IV), and levodopa equivalent daily dosage (LEDD) were analyzed before and after intervention. We found a predominantly male population, with no gender-related differences in age at onset, disease progression rate, or severity of disease. Nevertheless, women had more severe LIDs than men, only before the intervention. Bradykinesia was significantly less responsive to any kind of treatment (pharmacologic and neurosurgical) in women than in men. Finally, although STN-DBS induced similar total benefits in both genders, postoperative assessment suggested that the ADL improved more in women than in men. Women and men with advanced PD appear to differ in some clinical features and in response to dopaminergic and STN-DBS treatment.