Showing papers by "Kapil D. Sethi published in 2008"

Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS): scale presentation and clinimetric testing results.

Abstract: We present a clinimetric assessment of the Movement Disorder Society (MDS)-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS). The MDS-UDPRS Task Force revised and expanded the UPDRS using recommendations from a published critique. The MDS-UPDRS has four parts, namely, I: Non-motor Experiences of Daily Living; II: Motor Experiences of Daily Living; III: Motor Examination; IV: Motor Complications. Twenty questions are completed by the patient/caregiver. Item-specific instructions and an appendix of complementary additional scales are provided. Movement disorder specialists and study coordinators administered the UPDRS (55 items) and MDS-UPDRS (65 items) to 877 English speaking (78% non-Latino Caucasian) patients with Parkinson's disease from 39 sites. We compared the two scales using correlative techniques and factor analysis. The MDS-UPDRS showed high internal consistency (Cronbach's alpha = 0.79-0.93 across parts) and correlated with the original UPDRS (rho = 0.96). MDS-UPDRS across-part correlations ranged from 0.22 to 0.66. Reliable factor structures for each part were obtained (comparative fit index > 0.90 for each part), which support the use of sum scores for each part in preference to a total score of all parts. The combined clinimetric results of this study support the validity of the MDS-UPDRS for rating PD.

Levodopa Unresponsive Symptoms in Parkinson Disease

Abstract: Levodopa has been the mainstay of symptomatic therapy for Parkinson Disease (PD) for 40 years providing benefit to virtually all patients. Levodopa therapy results in improved activities of daily living, enhanced quality of life, and improved mortality. However, the long-term use of levodopa is associated with the development of motor fluctuations and dyskinesia. In addition, levodopa therapy has further limitations. It has little or no effect on certain motor features (e.g. gait and balance dysfunction) and a non-motor symptom complex (autonomic dysfunction, pain syndromes, sleep disorders, mood disturbances, dementia). Further, multiple case reports illustrate the potential of levodopa and other dopaminergic agents to cause or reveal a series of impulse control disorders. This review highlights the levodopa unresponsive symptoms in PD.

Sleep disorders associated with Parkinson's disease: role of dopamine, epidemiology, and clinical scales of assessment.

Abstract: Sleep dysfunction is common among patients with Parkinson's disease and occurs in approximately two thirds of patients. The problems range from nocturnal issues such as difficulty with sleep initiation, sleep fragmentation, disturbance of circadian rhythm, and rapid eye movement sleep behavior disorder, to daytime problems such as excessive daytime sleepiness. Frequent nighttime awakening and sleep disruption are the most common sleep problems in Parkinson's disease. Dopamine plays an important role in maintaining wakefulness. To improve sleep in Parkinson's disease, it is important to achieve the critical balance of adequate dopaminergic therapy and control of symptoms. Increased dopaminergic agents can cause dyskinesias and painful dystonia, and undertreatment can cause nighttime akinesia, rigidity, and worse quality of sleep. Other nondopaminergic drugs commonly used in Parkinson's disease can also affect sleep. In patients with advanced Parkinson's disease, deep brain stimulation of the subthalamic nucleus has a favorable impact on sleep quality and sleep architecture.

Rivastigmine for the treatment of dementia associated with Parkinson's disease.

Abstract: Parkinson's disease (PD) afflicts millions of people worldwide and leads to cognitive impairment or dementia in the majority of patients over time. Parkinson's disease dementia (PDD) is characterized by deficits in attention, executive and visuospatial function, and memory. The clinical diagnostic criteria and neuropathology surrounding PDD remain controversial with evidence of overlap among PDD, dementia with Lewy bodies (DLB) and Alzheimer's disease (AD). Cortical cholinergic deficits are greater in PDD than in AD, and are well-correlated with the cognitive and neuropsychiatric dysfunction that occurs in PDD. Inhibition of acetylcholine metabolism is therefore a practical therapeutic strategy in PDD.This review examines current evidence for rivastigmine (a cholinesterase/butyrylcholinesterase inhibitor) treatment in PDD. In addition to its efficacy, we examine the safety profile, side effects, and cost effectiveness of rivastigmine in PDD. Rivastigmine provides modest benefit in PDD and further long-term studies are needed to determine the effectiveness and safety of rivastigmine over time. Tolerability is a problem for many PDD patients treated with rivastigmine. Future studies of rivastigmine in PDD should focus on pragmatic outcomes such as time to need for nursing home placement, pharmacoeconomic outcomes and simultaneous patient/caregiver quality of life assessments.

Response to ropinirole in restless legs syndrome is independent of baseline serum ferritin

Abstract: Iron-deficient states can be associated with restless legs syndrome (RLS), and serum ferritin is recommended in screening for iron deficiency in RLS.1 2 Dopamine agonists are first-line treatment for idiopathic RLS, but it is not known if patients’ serum ferritin concentrations influence their responses to these drugs. We wanted to determine if patients with idiopathic RLS with lower serum ferritin (⩽50 μg/l) obtain similar benefit from ropinirole to those with “normal” (>50 μg/l) serum ferritin.2 A post hoc analysis of combined data from two pivotal RLS clinical trials revealed equal benefits of ropinirole over placebo in patients with serum ferritin above or below 50 μg/l. Data were pooled from two similarly designed, 12-week, randomised, double-blind, placebo-controlled studies of ropinirole in idiopathic RLS: TREAT RLS 1 and TREAT RLS 2.3 4 Serum ferritin concentrations were obtained at baseline in all patients entering both clinical trials. Subject inclusion and exclusion criteria have been described previously.3 4 Ropinirole 0.25–4.0 mg/day, or placebo, was titrated as needed and tolerated, and taken once a day 1–3 h before bedtime. Patient improvement at week 12 on the International Restless Legs Scale (IRLS) was the primary end point, and the proportion of patients responding to treatment on the Clinical Global Impression – Improvement (CGI-I) …

Neuroimaging and transcranial ultrasonography in Parkinson’s disease

Abstract: Parkinson’s disease is a progressive, widespread, neurodegenerative disease in which the involvement of the dopaminergic neurons of the substantia nigra results in significant dopamine depletion in the striatum. Newer imaging modalities reviewed here, using various radioligands, positron emission tomography, and single-photon emission computed tomography, have made it possible to assess the in vivo presynaptic and postsynaptic dopaminergic function. This is not only important from a diagnostic standpoint; these tests are being increasingly studied as surrogate markers to assess disease progression and responses to various interventions, including drugs. A brief comment on their role as a putative biomarker of the disease is also included. Because Parkinson’s disease involves multiple neurotransmitter systems, neuroimaging of neurotransmitter systems other than dopamine is also discussed. Lastly, the evidence supporting the use of transcranial ultrasonography and substantia nigra hyperechogenicity in the diagnosis of Parkinson’s disease is presented, along with some controversies that surround this technique.