[Myths and evidence on the use of botulinum toxin: neuropharmacology and dystonia]

INTRODUCTION

Botulinum toxin type A (BTA) is a bacterial endotoxin, whose therapeutic use has had a dramatic impact on different neurological disorders, such as dystonia and spasticity.

AIM

To analyze and summarize different questions about the use of BTA in our clinical practice.

DEVELOPMENT

A group of experts in neurology developed a list of topics related with the use of BTA. Two groups were considered: neuropharmacology and dystonia. A literature search at PubMed, mainly for English language articles published up to June 2016 was performed. The manuscript was structured as a questionnaire that includes those questions that, according to the panel opinion, could generate more controversy or doubt. The initial draft was reviewed by the expert panel members to allow modifications, and after subsequent revisions for achieving the highest degree of consensus, the final text was then validated. Different questions about diverse aspects of neuropharmacology, such as mechanism of action, bioequivalence of the different preparations, immunogenicity, etc. were included. Regarding dystonia, the document included questions about methods of evaluation, cervical dystonia, blepharospasm, etc.

CONCLUSION

This review does not pretend to be a guide, but rather a tool for continuous training of residents and specialists in neurology, about different specific areas of the management of BTA.

[Quantitative gait analysis in patients with advanced Parkinson's disease]

AIM

To describe the gait disorders and postural instability in a group of patients with advanced Parkinson's disease (PD).

PATIENTS AND METHODS

Gait was analysed in patients in advanced stages of PD on medication. Using a computerised analysis system, we studied the kinematic variables: cadence, number of correct gait cycles (HFPS cycles), total number of cycles, duration of the phases of the cycle, electromyography and a goniometric study of the knee and the ankle. The clinical appraisal of balance and postural instability was completed with the Tinetti and Timed Up and Go tests.

RESULTS

The analysis showed alterations in the spatio-temporal parameters with respect to the ranges considered to be normal: reduction of the HFPS cycles, increase in the total number of cycles and alteration of the cadence in many patients. It also revealed that the mean cadence was kept within the limits of normal values, an increase in the duration of the contact phase, reduction of monopodal support and alteration of the joint range of motion of the knee and the ankle. Likewise, changes are also observed in the scores obtained on the clinical scales, which show an increase in the risk factor for falls and mild dependence.

CONCLUSION

Quantification by objective analysis of the kinetic and kinematic variables in patients with PD can be used as a tool to establish the influence of the different therapeutic alternatives in gait disorders.

Use of e-mail for Parkinson's disease consultations: Are answers just a clic away?

INTRODUCTION

The clinical problems of patients with movement disorders (MD) are complex, and the duration and frequency of face-to-face consultations may be insufficient to meet their needs. We analysed the implementation of an e-mail-based query service for our MD unit's patients and their primary care physicians (PCPs).

METHODS

We retrospectively reviewed all consecutive emails sent and received over a period of 4 months, one year after implementation of the e-mail inquiry system. All patients received the during consultations, and PCPs, during scheduled informative meetings. We recorded and later analysed the profile of the questioner, patients' demographic and clinical data, number of queries, reason for consultation, and actions taken.

RESULTS

From 1 January 2015 to 30 April 2015, the service received 137 emails from 63 patients (43% male, mean age 71±10.5) diagnosed with Parkinson's disease (76%), atypical parkinsonism (10%), and others (14%); 116 responses were sent. Twenty (32%) emails were written by patients, 38 (60%) by their caregivers, and 5 (8%) by their PCPs. The reasons for consultation were clinical in 50 cases (80%): 16 (32%) described clinical deterioration, 14 (28%) onset of new symptoms, and 20 (40%) side effects or concerns about medications. In 13 cases (20%), the query was bureaucratic: 11 were related to appointments (85%) and 2 were requests for clinical reports (15%). In response, new appointments were scheduled in 9 cases (14%), while the rest of the questions were answered by email. Patients were satisfied overall and the additional care burden on specialists was not excessive.

CONCLUSIONS

Implementing an e-mail-based consultation system is feasible in MD units. It facilitates both communication between neurologists and patients and continued care in the primary care setting.

Gender differences in quality of life following subthalamic stimulation for Parkinson's disease

OBJECTIVES

Surveys of subthalamic nucleus (STN) deep brain stimulation (DBS) for Parkinson's disease (PD) have shown that this procedure is roughly twice more common in men than in women. Here, we investigate possible differences between women and men undergoing STN DBS, with respect to health-related quality of life.

MATERIALS AND METHODS

Forty-nine consecutive patients (18 women) received STN DBS. The impact of PD and its surgical treatment was compared between women and men, before and at mean of 19 ± 11 months after surgery, using the Unified Parkinson Disease Rating Scale (UPDRS) and the Parkinson's Disease Questionnaire-39 (PDQ-39).

RESULTS

Duration of disease at surgery and off-medication scores of the motor part of the UPDRS were similar in women and men. At baseline, women had lower doses of dopaminergic medication than men, experienced more disability due to dyskinesias, had more sensory symptoms and perceived more difficulties in mobility. Following DBS, both men and women showed equal and significant (P < 0.001) improvement in off-medication scores on the UPDRS III. On the PDQ-39, women expressed improvement in ADL to a greater extent than men. Moreover, women but not men showed a positive effect on mobility, stigma and cognition as well as on the summary score of PDQ-39.

CONCLUSIONS

Although STN DBS results in equal degree of motor improvement between women and men, health-related quality of life seems to improve to a greater extent in women.

MRI-guided STN DBS in Parkinson's disease without microelectrode recording: efficacy and safety

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is a commonly employed therapeutic procedure for patients with Parkinson's disease uncontrolled by medical therapies. This series describes the outcomes of 79 consecutive patients that underwent bilateral STN DBS at the National Hospital for Neurology and Neurosurgery between November 2002 and November 2008 using an MRI-guided surgical technique without microelectrode recording. Patients underwent immediate postoperative stereotactic MR imaging. The mean (SD) error in electrode placement was 1.3 (0.6)&emsp14;mm. There were no haemorrhagic complications. At a median follow-up period of 12&emsp14;months, there was a mean improvement in the off-medication motor part of the Unified Parkinson's Disease Rating Scale (UPDRS III) of 27.7 points (SD 13.8) equivalent to a mean improvement of 52% (p<0.0001). In addition, there were significant improvements in dyskinesia duration, disability and pain, with a mean reduction in on-medication dyskinesia severity (sum of dyskinesia duration, disability and pain from UPDRS IV) from 3.15 (SD 2.33) pre-operatively, to 1.56 (SD 1.92) post-operatively (p=0.0001). Quality of life improved by a mean of 5.5 points (median 7.9 points, SD 17.3) on the Parkinson's disease Questionnaire 39 summary index. This series confirms that image-guided STN DBS without microelectrode recording can lead to substantial improvements in motor disability of well-selected PD patients with accompanying improvements in quality of life and most importantly, with very low morbidity.