Matthew A. Brodsky

Randomized controlled trial of intraputamenal glial cell line-derived neurotrophic factor infusion in Parkinson disease.

Glial cell line–derived neurotrophic factor (GDNF) exerts potent trophic influence on midbrain dopaminergic neurons. This randomized controlled clinical trial was designed to confirm initial clinical benefits observed in a small, open‐label trial using intraputamenal (Ipu) infusion of recombinant human GDNF (liatermin).

A randomized, double-blind, placebo-controlled trial of antidepressants in Parkinson disease

Objective: To evaluate the efficacy and safety of a selective serotonin reuptake inhibitor (SSRI) and a serotonin and norepinephrine reuptake inhibitor (SNRI) in the treatment of depression in Parkinson disease (PD). Methods: A total of 115 subjects with PD were enrolled at 20 sites. Subjects were randomized to receive an SSRI (paroxetine; n = 42), an SNRI (venlafaxine extended release [XR]; n = 34), or placebo (n = 39). Subjects met DSM-IV criteria for a depressive disorder, or operationally defined subsyndromal depression, and scored >12 on the first 17 items of the Hamilton Rating Scale for Depression (HAM-D). Subjects were followed for 12 weeks (6-week dosage adjustment, 6-week maintenance). Maximum daily dosages were 40 mg for paroxetine and 225 mg for venlafaxine XR. The primary outcome measure was change in the HAM-D score from baseline to week 12. Results: Treatment effects (relative to placebo), expressed as mean 12-week reductions in HAM-D score, were 6.2 points (97.5% confidence interval [CI] 2.2 to 10.3, p = 0.0007) in the paroxetine group and 4.2 points (97.5% CI 0.1 to 8.4, p = 0.02) in the venlafaxine XR group. No treatment effects were seen on motor function. Conclusions: Both paroxetine and venlafaxine XR significantly improved depression in subjects with PD. Both medications were generally safe and well tolerated and did not worsen motor function. Classification of Evidence: This study provides Class I evidence that paroxetine and venlafaxine XR are effective in treating depression in patients with PD.

Sleepiness in Parkinson's disease: a controlled study.

Sudden‐onset sleep episodes while driving have been reported in Parkinsons disease (PD) patients, and termed sleep attacks because they were reported to be irresistible and to occur without warning. We postulate that these episodes are due to excessive daytime sleepiness secondary to the high frequency of sleep disorders in PD patients and the sedative effects of dopaminergic medications. We assessed the frequency and relationship between excess daytime sleepiness and sleep episodes while driving (SE) in patients with PD. We evaluated 101 consecutive PD patients presenting to the Movement Disorder Center at the Mount Sinai School of Medicine using a questionnaire that incorporated a subjective estimate of sleepiness, the Epworth Sleepiness Scale (ESS) and information on disease severity and dopaminergic medications. One hundred age‐matched respondents without PD served as a control population. Excess daytime sleepiness was reported in 76% of PD patients compared to 47% of controls (P < 0.05). The mean ESS scores for PD patients was 9.1 ± 6.1 versus 5.7 ± 4.4 in controls (P < 0.001). ESS scores ≥10 were observed in 40.6% of PD patients compared to 19% of controls (P < 0.01) and 24% of PD patients had scores ≥15, compared to 5% of controls (P < 0.001). Sleep episodes while driving were experienced by 20.8% of PD drivers compared to 6% of control drivers (P < 0.05). The mean daily levodopa (L‐dopa) dose equivalent was 1,142 ± 858 mg in PD drivers who experienced a SE while driving compared to 626 ± 667 mg in those who had not (P < 0.05). Similarly, ESS was significantly greater in drivers with a SE than in those without (11.6 ± 6.4 vs. 8.4 ± 4.1; P < 0.05). Logistic regression analysis demonstrated that ESS and mean daily L‐dopa dose equivalents were predictors of sleep episodes while driving, whereas age, gender, disease severity, and individual dopaminergic agents were not. These findings support the notion that sleep episodes while driving in PD patients are related to excess daytime sleepiness and dopaminergic load. Physicians should advise and treat patients accordingly.

Long-term efficacy and safety of botulinum toxin type A (Dysport) in cervical dystonia

The aim of this study was to evaluate the efficacy and safety of intramuscular (IM) administration of botulinum toxin type A (Dysport((R)), Ipsen Biopharm Ltd.) for the treatment of cervical dystonia (CD) and the long-term safety and efficacy of repeated treatments. During the randomized, double-blind, placebo-controlled phase patients were randomized to 500 units Dysport (n = 55) or placebo (n = 61). Efficacy assessments included the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) total and subscale scores, visual analogue scale (VAS) for pain, subject/investigators VAS for symptom assessments. Patients completing the double-blind treatment could enter an open-label extension phase and receive up to 4 additional Dysport treatments. Dysport produced a significant decrease from baseline in mean (+/-SE) TWSTRS total scores compared with placebo at Week 4 (primary efficacy endpoint; -15.6 +/- 2.0 vs. -6.7 +/- 2.0; p < 0.001) with significant improvements sustained to Week 12 (p = 0.019). Dysport also produced significant improvements in TWSTRS subscale scores, VAS pain scores, and subject/investigators VAS symptom assessments compared to placebo. The mean duration of open-label study participation was 51.9 weeks (range 3.9-94.0 weeks). During open-label treatment, all treatment cycles resulted in improvements in mean TWSTRS total and subscale scores at Week 4 post-treatment; greatest improvement was seen in cycle 1. The mean duration between treatment cycles was 15-17 weeks. Dysport demonstrated a good long-term safety profile; most adverse events were mild or moderate and typical of the known safety profile of Dysport in this indication. These results confirm that Dysport (500 units) is safe, effective, and well-tolerated in patients with CD.

Diffusion of Botulinum Toxins

Background It is generally agreed that diffusion of botulinum toxin occurs, but the extent of the spread and its clinical importance are disputed. Many factors have been suggested to play a role but which have the most clinical relevance is a subject of much discussion. Methods This review discusses the variables affecting diffusion, including protein composition and molecular size as well as injection factors (e.g., volume, dose, injection method). It also discusses data on diffusion from comparative studies in animal models and human clinical trials that illustrate differences between the available botulinum toxin products (onabotulinumtoxinA, abobotulinumtoxinA, incobotulinumtoxinA, and rimabotulinumtoxinB). Results Neither molecular weight nor the presence of complexing proteins appears to affect diffusion; however, injection volume, concentration, and dose all play roles and are modifiable. Both animal and human studies show that botulinum toxin products are not interchangeable, and that some products are associated with greater diffusion and higher rates of diffusion-related adverse events than others. Discussion Each of the botulinum toxins is a unique pharmacologic entity. A working knowledge of the different serotypes is essential to avoid unwanted diffusion-related adverse events. In addition, clinicians should be aware that the factors influencing diffusion may range from properties intrinsic to the drug to accurate muscle selection as well as dilution, volume, and dose injected.

Neurologic drug-psychotropic drug update

It is essential that both the neurologist and the psychiatrist be aware of the neurology drug-psychotropic drug interactions because neurologists prescribe many psychotropic medications and psychiatric consultants often recommend the use of psychotropic drugs for neurology patients. Six methods of examining drug-drug interactions were employed: 1) PubMed (MEDLINE); 2) Hanstons Drug Interaction Analysis and Management Text (July 2001 quarterly updated version); 3)Drug Interactions Facts (quarterly updated version through July 2001); 4) Micromedex Drug-dex; 5) American Hospital Formulary Service Drug Information; 6) Food and Drug Administration (MedWatch) Dear Doctor Letters and new labeling. Over eighty important interactions of significance level 1 (major), or significance level 2 (minor) were found. Furthermore, over one-third of the neurologists most commonly administered medications were those also employed by the psychiatrist, but not necessarily for the same reason, e.g., carbamazepine, for seizure control (neurologist) or mood stabilization (psychiatrist).

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

A 61‐year‐old man with Parkinsons 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.

Clinical outcomes of asleep vs awake deep brain stimulation for Parkinson disease

Objective: To compare motor and nonmotor outcomes at 6 months of asleep deep brain stimulation (DBS) for Parkinson disease (PD) using intraoperative imaging guidance to confirm electrode placement vs awake DBS using microelectrode recording to confirm electrode placement. Methods: DBS candidates with PD referred to Oregon Health & Science University underwent asleep DBS with imaging guidance. Six-month outcomes were compared to those of patients who previously underwent awake DBS by the same surgeon and center. Assessments included an “off”-levodopa Unified Parkinson’s Disease Rating Scale (UPDRS) II and III, the 39-item Parkinsons Disease Questionnaire, motor diaries, and speech fluency. Results: Thirty participants underwent asleep DBS and 39 underwent awake DBS. No difference was observed in improvement of UPDRS III (+14.8 ± 8.9 vs +17.6 ± 12.3 points, p = 0.19) or UPDRS II (+9.3 ± 2.7 vs +7.4 ± 5.8 points, p = 0.16). Improvement in “on” time without dyskinesia was superior in asleep DBS (+6.4 ± 3.0 h/d vs +1.7 ± 1.2 h/d, p = 0.002). Quality of life scores improved in both groups (+18.8 ± 9.4 in awake, +8.9 ± 11.5 in asleep). Improvement in summary index (p = 0.004) and subscores for cognition (p = 0.011) and communication (p < 0.001) were superior in asleep DBS. Speech outcomes were superior in asleep DBS, both in category (+2.77 ± 4.3 points vs −6.31 ± 9.7 points (p = 0.0012) and phonemic fluency (+1.0 ± 8.2 points vs −5.5 ± 9.6 points, p = 0.038). Conclusions: Asleep DBS for PD improved motor outcomes over 6 months on par with or better than awake DBS, was superior with regard to speech fluency and quality of life, and should be an option considered for all patients who are candidates for this treatment. Clinicaltrials.gov identifier: NCT01703598. Classification of evidence: This study provides Class III evidence that for patients with PD undergoing DBS, asleep intraoperative CT imaging–guided implantation is not significantly different from awake microelectrode recording–guided implantation in improving motor outcomes at 6 months.

Comparison of three methods for identifying medical drug-psychotropic drug interactions☆

Three methods for examining drug-drug interactions were compared to understand advantages and disadvantages of each: ePocrates; Interact; The Mount Sinai multiple source for the evaluation of drug-drug interactions (MS). ePocrates is a commonly employed software system utilized in a hand held computer, the PalmPilot. Interact is on a CD-ROM, and promoted by the American Psychiatric Association Press. The MS system was developed by the authors and utilizes six separate references sources to ascertain the presence and significance of drug-drug interactions. Commonly prescribed neurology and psychotropic medication interactions were compared using the three systems. ePocrates did not list the significance level of the interaction, e.g., (major, moderate, minor), often did not include a mechanism of action, and several commonly employed medications were not included. It did permit examining several drugs at the same time, and was easily carried on the person of the physician. Interact often contained old references, several drugs were not included, was not adapted to a hand held computer format, and had no update since 1999. The MS system listed level of significance, provided mechanism of action, and advice to the practitioner including recommendations. It is not portable, requiring a laptop or desk top computer or hard copy, and only searches one drug at a time. It is hoped that the advantages of each of these three systems may be incorporated into systems of the future.

Trial of dextromethorphan/quinidine to treat levodopa-induced dyskinesia in Parkinson's disease.

Background: Nondopaminergic pathways represent potential targets to treat levodopa‐induced dyskinesia in Parkinsons disease (PD). This pilot‐study (NCT01767129) examined the safety/efficacy of the sigma‐1 receptor‐agonist and glutamatergic/monoaminergic modulator, dextromethorphan plus quinidine (to inhibit rapid dextromethorphan metabolism), for treating levodopa‐induced dyskinesia.