Parkinson Disease: Factor SA

Pahwa R, Factor SA, Lyons KE, Ondo WG, Gronseth G, Bronte-Stewart H, Hallett M, Miyasaki J, Stevens J, Weiner WJ, Anonymous00045. · University of Kansas Medical Center, Kansas City, USA. · Neurology. · Pubmed #16606909 No free full text.

Abstract: OBJECTIVE: To make evidence-based treatment recommendations for the medical and surgical treatment of patients with Parkinson disease (PD) with levodopa-induced motor fluctuations and dyskinesia. To that end, five questions were addressed. 1. Which medications reduce off time? 2. What is the relative efficacy of medications in reducing off time? 3. Which medications reduce dyskinesia? 4. Does deep brain stimulation (DBS) of the subthalamic nucleus (STN), globus pallidus interna (GPi), or ventral intermediate (VIM) nucleus of the thalamus reduce off time, dyskinesia, and antiparkinsonian medication usage and improve motor function? 5. Which factors predict improvement after DBS? METHODS: A 10-member committee including movement disorder specialists and general neurologists evaluated the available evidence based on a structured literature review including MEDLINE, EMBASE, and Ovid databases from 1965 through June 2004. RESULTS, CONCLUSIONS, AND RECOMMENDATIONS: 1. Entacapone and rasagiline should be offered to reduce off time (Level A). Pergolide, pramipexole, ropinirole, and tolcapone should be considered to reduce off time (Level B). Apomorphine, cabergoline, and selegiline may be considered to reduce off time (Level C). 2. The available evidence does not establish superiority of one medicine over another in reducing off time (Level B). Sustained release carbidopa/levodopa and bromocriptine may be disregarded to reduce off time (Level C). 3. Amantadine may be considered to reduce dyskinesia (Level C). 4. Deep brain stimulation of the STN may be considered to improve motor function and reduce off time, dyskinesia, and medication usage (Level C). There is insufficient evidence to support or refute the efficacy of DBS of the GPi or VIM nucleus of the thalamus in reducing off time, dyskinesia, or medication usage, or to improve motor function. 5. Preoperative response to levodopa predicts better outcome after DBS of the STN (Level B).

Factor SA. · Department of Neurology, Emory University School of Medicine, Atlanta, Georgia 30329, USA. · Mov Disord. · Pubmed #18668624 No free full text.

Abstract: Freezing of gait (FOG), commonly seen in advanced Parkinson's disease (PD), has been classified as its fifth cardinal feature. However, its presence frequently leads to a misdiagnosis of PD. FOG is actually more common in atypical parkinsonism (AP): including vascular Parkinsonism (VP), progressive supranuclear palsy (PSP), multiple system atrophy (MSA), corticobasal degeneration (CBD), dementia with Lewy bodies (DLB), and higher level gait disorders (HLGDs). VP is the result of multiple small vessel infarcts (lacunar state or Binswanger's disease), particularly involving the frontal, parietal, and basal ganglia regions. Approximately 50% have FOG (often referred to as lower body parkinsonism). FOG is also common in neurodegenerative forms of AP, present in 45-57%. Of these, FOG is present in 53% of PSP, 54% MSA, 54% DLB, 25% CBD, and 40% HLGD. It is generally seen in the late stages. There are two syndromes closely associated with AP that are dominated by FOG; pure akinesia (PA) and primary progressive freezing gait (PPFG). PA is characterized by akinesia of gait (including FOG), writing, and speech. Tremor, rigidity, dementia, and response to levodopa are notably absent. PPFG is defined by early FOG (often the initial feature) that progresses to include postural instability. It is accompanied by bradykinesia, rigidity, postural tremor, dementia, and levodopa unresponsiveness. Both syndromes are heterogeneous but PSP seems to be the most common cause. CBD and DLB can also present as PPFG. FOG is a common feature of AP and although typically occurring late in disease may also be an early symptom.

Factor SA. · Department of Neurology, Emory University School of Medicine, 1841 Clifton Road NE, Atlanta, Georgia 30329, USA. · Neurotherapeutics. · Pubmed #18394561 No free full text.

Abstract: Symptomatic medical therapies for Parkinson's disease (PD) have been disease modifying and have led to improvement in daily function, quality of life, and survival. For 40 years, these therapies have been primarily dopaminergic, and currently include the dopamine (DA) precursor levodopa (LD), DA agonists, catechol-O-methyltransferase (COMT) inhibitors, and monoamine oxidase (MAO) inhibitors. The roles of all these classes of agents have evolved, with significant changes occurring since the early 2000s. This article reviews the current literature for each of these classes of drugs, with a focus on efficacy and place in the therapeutic scheme. Levodopa is no longer considered to be toxic and, thus, its early use is not only appropriate but recommended. Ergot agonists are no longer in use, and new agents administered in patch form or subcutaneous injections have been approved. The COMT inhibitor tolcapone, with its significant efficacy, has been reintroduced, and two new MAO inhibitors have been approved. Selected safety issues are discussed, including the incidence of melanoma in relation to LD; pathological gambling and DA agonists; hepatic toxicity of tolcapone; and the tyramine or so-called cheese reaction with MAO B inhibitors. The article closes with a discussion of future directions and new drugs under development.

Esper CD, Weiner WJ, Factor SA. · Department of Neurology Emory University School of Medicine, Atlanta, GA, USA. · Rev Neurol Dis. · Pubmed #18195676 No free full text.

Abstract: Since progressive supranuclear palsy (PSP) was first reported as a separate clinicopathological entity in 1964, hundreds of other cases have been recorded, and PSP is now one of the most common atypical Parkinson-plus disorders. Diagnostic criteria have been developed by the National Institute of Neurological Disorders and Stroke and the Society for PSP, Inc. Because there is no biological marker for PSP, definitive diagnosis depends on neuropathological examination. Characteristics of PSP include gait disturbances, supranuclear ophthalmoplegia, axial limb rigidity, and frontal lobe dysfunction. Although there are no treatments that alter the natural history of disease in PSP and no drugs that provide significant symptomatic benefits, several supportive measures are available.

Factor SA. · Parkinson's Disease and Movement Disorders Center of Albany Medical Center, Albany, New York 12205, USA. · Neurology. · Pubmed #15037666 No free full text.

Abstract: Apomorphine injectable has been used in Europe for more than a decade as a rescue therapy for intractable "off" periods in Parkinson's disease (PD). Some studies were performed as early as the 1970's. This article reviews double-blind and open studies with apomorphine for PD prior to the year 2000. Most were performed in Europe. Double-blind studies with injection doses of 1-5 mg have demonstrated that onset of clinical benefit typically occurs within 10 minutes, and lasts for up to two hours. The magnitude of benefit rivals that of levodopa. Long-term, open-label studies have demonstrated the persistent response to apomorphine injectable as a rescue therapy for as long as five years. Duration of benefit and dose of a single injection remains the same, but a need for increased number of doses per day is reported in keeping with disease progression. For many patients, the need for concomitant domperidone administration for antiemesis wanes over time. Apomorphine has also been shown in smaller studies to be effective for a variety of non-motor "off" phenomena, including pain, panic attacks, and a variety of gastrointestinal symptoms. Subutaneous intermittent bolus injects are also useful in patients post operatively who are unable to take oral medications.

Molho ES, Factor SA. · Parkinson's Disease and Movement Disorder Center, Albany Medical Center, 215 Washington Ave. Extension, Albany, NY 12203, USA. · Curr Neurol Neurosci Rep. · Pubmed #11898537 No free full text.

Abstract: Drug-induced psychosis is one of the most disabling complications of advancing Parkinson's disease. It has also been one of the most difficult to treat. Clozapine was the first medication shown to be safe and effective in this setting, and it remains the standard by which newer atypical antipsychotics are measured. However, due to the small but significant risk of agranulocytosis and the need for frequent blood testing, alternatives have been sought. Risperidone, olanzapine, and quetiapine are new atypical antipsychotics that have each been proposed as an alternative to clozapine, but the literature concerning their use in Parkinson's disease is conflicted and confusing. Although quetiapine appears to be the best current choice, none of these medications have equaled clozapine's ability to safely treat drug-induced psychosis without the risk of worsening parkinsonism.

Friedman JH, Factor SA. · Memorial Hospital of Rhode Island, Pawtucket 02860, USA. · Mov Disord. · Pubmed #10752567 No free full text.

Abstract: Our experience with atypical antipsychotics in patients with PD is that their motor effects are not predictable. The multiple reports concerning clozapine's beneficial effects on tremor, dystonia, nocturnal akathisia, and dyskinesias all underscore this observation. However, the appearance of even minor degrees of parkinsonism in normal volunteers or schizophrenics should suggest that an antipsychotic will not be well-tolerated in patients with PD. The treatment of PD is probably the most stringent test of a drug's freedom from parkinsonian side effects. The data from trials in schizophrenia concerning parkinsonian effects cannot always be confidently interpreted. Virtually all subjects in these trials have been treated with typical neuroleptics until shortly before study entry. Because the parkinsonian side effects of these drugs may persist for several months, patients may still show declining levels of parkinsonism even when placed on a drug that induces it if this effect is milder than that induced by the pre-study neuroleptic. Depending on the pre-study drug used and the duration of the study, distinguishing placebo from a low-potency neuroleptic may be impossible. Furthermore, the standard measure of parkinsonism in psychiatric studies is the Simpson-Angus scale which is heavily weighted toward rigidity and may underscore bradykinesia, gait, and posture abnormalities. The prolactin response to an antipsychotic drug may turn out to be a good predictor of its freedom from parkinsonian side effects. That would fit with the data presented above of clozapine and quetiapine having less parkinsonian effects, olanzapine having more but variable effects and risperidone being poorly tolerated. With the data presented above, comprising a current review of all reports of the use of atypical antipsychotics in PD that we could locate, we can say little with certainty. The only drug with confirmed benefit without worsening parkinsonism is clozapine. Open-label trials involving over 400 patients and two multicenter, placebo-controlled, double-blind trials have demonstrated that it is effective in treating the psychosis. It improves tremor, does not worsen other motor functions to any significant extent, and is safe at low doses. Limited data provide conflicting information on both risperidone and olanzapine. Quetiapine seems to be well-tolerated with some, but definitely less, worsening of PD motor features than risperidone and olanzapine. Based on the current literature, our personal experience, and anecdotal experience of other PD specialists which we solicited, we will venture our own interpretation and recommendations. We think risperidone is poorly tolerated and should be used only as a last resort; that olanzapine is better than risperidone but will, in a majority of patients with PD, worsen motor function. We are optimistic, but not yet convinced, that quetiapine may prove to be as effective and better tolerated than clozapine. It will not require cumbersome monitoring because it does not induce a blood dyscrasia. We therefore recommend that DP be treated in the following manner. First, the anti-PD medications should be simplified and reduced as much as tolerated. We think, in general, side effects multiply more with increasing numbers of drugs than with drug dose, so that patients are more likely to tolerate a higher dose of levodopa than a lower dose of levodopa combined with other adjunctive anti-PD medications. In reducing anti-PD medications, we recommend tapering and stopping, if necessary, the drugs with the highest risk-to-benefit ratio first. Anticholinergics are stopped first, then selegiline, dopamine agonists, amantadine, and finally COMT inhibitors, which have no psychotomimetic action of their own. Finally, levodopa is reduced. Generally, a point is reached at which the anti-PD medications cannot be reduced without jeopardizing motor function. If psychosis persists at this point, then an antipsychotic is added. (ABS

Factor SA, Molho ES. · Albany Medical College, Department of Neurology, NY, USA. · Am J Emerg Med. · Pubmed #10750935 No free full text.

Abstract: Parkinson's disease (PD) is a chronic progressive neurological disorder characterized by tremor, muscle rigidity, slowness of movement (bradykinesia), and gait instability. In early disease, PD is well managed in an office setting, however, as the disease progresses, a variety of syndromes may result in emergency department visits. The scenarios most likely to require an emergent evaluation are severe motor "off" periods with immobility, involuntary movements (dyskinesia), psychosis, acute confusion, panic disorder, and pain. Other less frequent presentations are also discussed. This article uses illustrative cases to provide a framework to discuss emergency department diagnosis and management issues in caring for these patients.

Factor SA, Molho ES. · Department of Neurology, Albany Medical College, New York, USA. · Mov Disord. · Pubmed #10348482 No free full text.

This publication has no abstract.

Factor SA. · Department of Neurology, Albany Medical College, New York, USA. · Med Clin North Am. · Pubmed #10093586 No free full text.

Abstract: Dopamine agonists have been used in the treatment of Parkinson's disease (PD) since the mid 1970s. With the approval of two new agents in 1997, the number available in the United States is up to four; bromocriptine, pergolide, pramipexole, ropinirole. These agents differ in dopamine receptor affinities and chemical structure, which, in turn, may possibly result in differences in efficacy tolerability and safety. Dopamine have historically been used in combination with levodopa in patients with advanced PD, but indicators are now expanding. With is expansion comes increasing controversy. This article reviews dopamine receptor pharmacology and the results of the clinical trials that have used for agonists available in the United States as well as a discussion of three minor agonists.

Pahwa R, Stacy MA, Factor SA, Lyons KE, Stocchi F, Hersh BP, Elmer LW, Truong DD, Earl NL, Anonymous00439. · University of Kansas Medical Center, Kansas City, KS 66160, USA. · Neurology. · Pubmed #17404192 No free full text.

Abstract: OBJECTIVE: To evaluate the efficacy of ropinirole 24-hour prolonged release (ropinirole 24-hour) as an adjunct to levodopa in patients with Parkinson disease (PD) and motor fluctuations. METHODS: In a double-blind, placebo-controlled, 24-week study, 393 subjects with PD were randomized to ropinirole 24-hour (n = 202) or placebo (n = 191). The primary outcome measure was reduction in hours of daily "off" time. RESULTS: At week 24, the mean dose of ropinirole 24-hour was 18.8 mg/day with a mean reduction in daily levodopa of 278 mg. There was a mean reduction in daily "off" time of 2.1 hours in the ropinirole 24-hour group and 0.3 hours with placebo. Secondary outcome measures including change in hours and percent of daily "on" time and "on" time without troublesome dyskinesia, Unified PD Rating Scale motor and activities of daily living subscales, Beck Depression Inventory-II, PDQ-39 subscales of mobility, activities of daily living, emotional well-being, stigma and communication, and PD Sleep Scale were significantly improved at week 24 with ropinirole 24-hour. The most common adverse events (AE) with ropinirole 24-hour were dyskinesia, nausea, dizziness, somnolence, hallucinations, and orthostatic hypotension and AEs led to study withdrawal in 5% of both the active and placebo groups. CONCLUSION: Ropinirole 24-hour was effective and well tolerated as adjunct therapy in patients with Parkinson disease (PD) not optimally controlled with levodopa. Ropinirole 24-hour demonstrated an improvement in both motor and non-motor PD symptoms, while permitting a reduction in adjunctive levodopa dose.

Factor SA, Feustel PJ, Friedman JH, Comella CL, Goetz CG, Kurlan R, Parsa M, Pfeiffer R, Anonymous00282. · Albany Medical Center, NY 12205, USA. · Neurology. · Pubmed #12796526 No free full text.

Abstract: OBJECTIVES: To examine the long-term outcome of PD patients with psychosis requiring antipsychotic therapy; to explore predictors of mortality, nursing home placement, dementia, and persistent psychosis; and to compare outcomes of those with persistent psychosis vs those whose psychosis resolved. METHODS: Baseline data available from 59 patients enrolled in the PSYCLOPS (PSychosis and CLOzapine in PD Study) trial included age, age at onset of PD, duration of PD and psychosis, character of psychosis, medications, living setting, and scores for Mini-Mental State Examination (MMSE), Unified Parkinson's Disease Rating Scale, Hoehn and Yahr Scale, and Clinical Global Impression Scale. Longitudinal data were collected 26 months later regarding four outcomes: death, nursing home placement, diagnosis of dementia, and persistence of psychosis. Logistic regression was used to explore whether any baseline characteristics were associated with an increased likelihood of one of these outcomes. RESULTS: At baseline, 56% of patients had an MMSE score of <25, 12% were in a nursing home, 95% had hallucinations, and 60% had paranoia. On follow-up, 25% were dead, nursing home placement occurred in 42%, psychosis was persistent in 69%, and dementia was diagnosed in 68%. Select baseline characteristics predicted individual outcomes: Nursing home placement was associated with the presence of paranoia and older age; persistent psychosis was associated with younger age at onset of PD and longer disease duration; dementia was associated with older age at PD onset and lower initial MMSE score; no characteristics predicted death. Whether psychosis persisted or not had no significant effect on the development of the other three outcomes. The prevalence of hallucinations at follow-up was not different between groups currently receiving antipsychotics vs those on no treatment. CONCLUSIONS: Psychosis in PD requiring antipsychotic therapy is frequently associated with death, nursing home placement, development and progression of dementia, and persistence of psychosis. Still, it appears the prognosis has improved with atypical antipsychotic therapy based on the finding that 28% of NH patients died within 2 years compared with 100% in a previous study done prior to availability of this treatment.

Factor SA, Molho ES, Feustel PJ, Brown DL, Evans SM. · Department of Neurology, Albany Medical Center, Albany, New York 12203, USA. · Clin Neuropharmacol. · Pubmed #11586115 No free full text.

Abstract: The objective of this study was to compare the long-term tolerability and efficacy of tolcapone and entacapone in patients with fluctuating Parkinson's disease (PD). Tolcapone and entacapone are two currently available catechol- O -methyltransferase inhibitors that have demonstrated efficacy in the treatment of advanced PD. There are little published data on long-term experience and no direct comparisons. We compared the results of two separate, simultaneous, long-term open label extensions, one for tolcapone and the other for entacapone. The inclusion/exclusion criteria were similar. Data were collected prospectively at 6, 12, 24, and 36 months. Efficacy measures included the Unified Parkinson's Disease Rating Scale (UPDRS) total score, subscores, items 32 (duration of dyskinesia) and 39 (duration of "off" time), and levodopa dose. The two groups were compared using a Mann-Whitney U test for change from baseline and analysis of variance. Tolerability was defined as the ability of patients to maintain therapy and was compared using a Kaplan-Meier analysis. Eleven patients enrolled in the entacapone study and 14 in the tolcapone study. The tolcapone group had more severe disease with significantly higher UPDRS motor score, duration of "off," and levodopa dose requirement. Tolcapone was more effective in lowering UPDRS motor and complication subscores, duration of "off" time, and levodopa doses. UPDRS motor scores and change in levodopa dose in the tolcapone group remained below baseline level for 36 months; however, they were above baseline in the entacapone group from 6 months on. Tolerability was the same for both treatments. Tolcapone appears to have greater and longer efficacy with regard to motor symptoms, "off" time, and change in levodopa requirements than entacapone. These findings indicate that tolcapone continues to have a place in the treatment of advanced PD. However, the risks associated with this drug, particularly hepatic injury, and the requirement for rigorous blood monitoring, need to be considered when choosing an appropriate treatment for patients with advanced PD.

Dewey RB, Hutton JT, LeWitt PA, Factor SA. · Department of Neurology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-9036, USA. · Arch Neurol. · Pubmed #11559309 links to  free full text

Abstract: OBJECTIVE: To assess the safety and efficacy of subcutaneous apomorphine hydrochloride administration for off-state (poor motor function) periods in patients with Parkinson disease with motor fluctuations under both inpatient titration and outpatient therapeutic conditions. PATIENTS AND METHODS: Twenty-nine patients had advanced Parkinson disease with 2 hours or more off time despite aggressive oral therapy. Patients randomly received titrated doses of subcutaneous apomorphine hydrochloride (2-10 mg, n = 20) or pH-matched vehicle placebo (n = 9) during an inpatient and 1-month outpatient phase. A change in the United Parkinson Disease Rating Scale motor score 20 minutes after inpatient dosing during a practically defined off-state event and the percentage of injections successfully aborting off-state events were the primary inpatient and outpatient efficacy factors. RESULTS: The average (SEM) levodopa equivalent dose of apomorphine hydrochloride was 5.4 +/- 0.5 mg and the mean placebo dose was 1.0 mL. Mean inpatient United Parkinson Disease Rating Scale motor scores were reduced by 23.9 and 0.1 points (62% and 1%) by apomorphine treatment and placebo, respectively (P<.001). The mean percentage of outpatient injections resulting in successful abortion of off-state events was 95% for apomorphine and 23% for placebo (P<.001). Inpatient response was significantly correlated with and predictive of outpatient efficacy (P<.001). The levodopa dose was not predictive of the apomorphine dose requirement. Frequent adverse events included dyskinesia, yawning, and injection site reactions. CONCLUSION: Apomorphine by intermittent subcutaneous injection is effective and safe for outpatient use to reverse off-state events that occur despite optimized oral therapy.

Factor SA, Friedman JH, Lannon MC, Oakes D, Bourgeois K, Anonymous00168. · Albany Medical College, New York, USA. · Mov Disord. · Pubmed #11215574 No free full text.

Abstract: OBJECTIVE: To report the results of the 12-week, prospective, open label extension of the 4-week, multicenter, placebo-controlled, double-blind PSYCLOPS (PSYchosis and CLOzapine in the treatment of Parkinsonism) trial. This extension examined the chronic safety and efficacy of clozapine in the treatment of drug-induced psychosis in Parkinson's disease (PD). BACKGROUND: Psychosis is a serious late complication of PD and may be a harbinger to increased mortality. Clozapine, the first atypical antipsychotic, was shown in several small open label studies to improve psychosis without worsening of motor symptoms. This was recently confirmed in the double-blind PSYCLOPS trial. METHODS: The 53 patients who completed the double-blind portion of PSYCLOPS were evaluated on their original randomized treatment (clozapine or placebo), then had study medication stopped. All were started on clozapine. The patients from both treatment groups were evaluated every 4 weeks over a 12-week period using standardized measures for psychosis and PD. RESULTS: The mean dose of clozapine was 28.78 mg/day. Those originally treated with placebo improved significantly in Brief Psychiatric Rating Scale and clinical global scores for psychosis to the same degree as the group originally randomized to clozapine in the double-blind study. Both groups maintained their response to week 16 (end of the combined double-blind and open label portions). There was no worsening of motor features as measured by the Unified Parkinson's disease rating scale. Eighteen patients were either hospitalized or died during the trial. The most common reasons were pulmonary. CONCLUSIONS: Low-dose clozapine is effective in treating drug-induced psychosis without worsening motor features of PD, and the response is maintained for at least 4 months. Patients with psychosis and PD were previously described as a group with high risk for morbidity and mortality. The high risk continues despite antipsychotic therapy.

Hauser RA, Friedlander J, Zesiewicz TA, Adler CH, Seeberger LC, O'Brien CF, Molho ES, Factor SA. · Department of Neurology, University of South Florida, Tampa, USA. · Clin Neuropharmacol. · Pubmed #10803796 No free full text.

Abstract: In clinical trials for patients with Parkinson's disease (PD) with motor fluctuations, efficacy is generally ascribed to an intervention if motor function is significantly improved or if "off" time is significantly reduced. However, we have argued that patients might not be improved if off time is reduced only to the extent that unwanted dyskinesia is increased. Therefore, a home diary should include an assessment of dyskinesia to provide an accurate reflection of clinical status over a period of time. We undertook two studies to develop a home diary to assess functional status in patients with PD with motor fluctuations and dyskinesia. In both studies, patients concurrently completed a test and a reference diary. In Study I, we evaluated the impact of different severities of dyskinesia on patient-defined functional status. There were 1,149 evaluable half-hour time periods from 24 patients; 94.3% of off time was considered "bad" time and 90.2% of "on" time without dyskinesia, 72.6% of on time with mild dyskinesia, 43.0% of on time with moderate dyskinesia, and 15.2% of on time with severe dyskinesia was considered "good" time. In Study II, we evaluated a new home diary designed to separate dyskinesia that had a negative impact on patient-defined functional status from dyskinesia that did not. There were 816 evaluable time periods from 17 patients; 84.9% of off time and 89.9% of on time with troublesome dyskinesia was considered bad time while 85.5% of on time without dyskinesia and 93.8% of on time with nontroublesome dyskinesia was considered good time. With this diary (Diary II), the effect of an intervention can be expressed as the change in off time and the change in on time with troublesome dyskinesia (bad time). The sum can be used as an outcome variable and compared to baseline or across groups. In evaluating the efficacy of an intervention, assessment of change in off time and change in on time with troublesome dyskinesia provides a more accurate reflection of clinical response than change in off time alone.

Kay DM, Factor SA, Samii A, Higgins DS, Griffith A, Roberts JW, Leis BC, Nutt JG, Montimurro JS, Keefe RG, Atkins AJ, Yearout D, Zabetian CP, Payami H. · New York State Department of Health, Division of Genetic Disorders, Wadsworth Center, Albany, New York 12208, USA. · Am J Med Genet B Neuropsychiatr Genet. · Pubmed #18404644 No free full text.

Abstract: Point mutations and copy number variations in SNCA, the gene encoding alpha-synuclein, cause familial Parkinson's disease (PD). A dinucleotide polymorphism (REP1) in the SNCA promoter may be a risk factor for common forms of PD. We studied 1,802 PD patients and 2,129 controls from the NeuroGenetics Research Consortium, using uniform, standardized protocols for diagnosis, subject recruitment, data collection, genotyping, and data analysis. Three common REP1 alleles (257, 259, and 261 bp, with control frequencies of 0.28, 0.65, and 0.06) and several rare alleles (combined frequency <0.01) were detected. We confirmed association of REP1 with PD risk [odds ratio (OR) = 0.86, P = 0.006 for 257-carriers; OR = 1.25, P = 0.022 for 261-carriers]. Using a normalization procedure, we showed that the 257 and 261 alleles are both independently associated with PD risk (for 257, P = 0.002 in overall data, 0.003 in non-familial PD, 0.001 in early-onset PD; for 261, P = 0.056 in overall data, 0.024 in non-familial PD, 0.052 in early-onset PD). The 257-associated risk was consistent with a dominant model [hazard ratio (HR) = 0.99, P = 0.91 for 257/257 vs. 257/X where X denotes all other common alleles; HR = 1.16, P = 0.004 for X/X vs. 257/X]. The 261-associated risk was consistent with a recessive model (HR = 1.89, P = 0.026 for 261/261 vs. 261/X; HR = 0.95, P = 0.42 for X/X vs. 261/X). Genotype-specific mean onset ages (+/-SD) ranged from 54.8 +/- 12.1 for 261/261 to 59.4 +/- 11.5 for 257/257, displaying a trend of decreasing onset age with increasing allele size (P = 0.055). Genetic variation in SNCA and its regulatory regions play an important role in both familial and sporadic PD.

McCulloch CC, Kay DM, Factor SA, Samii A, Nutt JG, Higgins DS, Griffith A, Roberts JW, Leis BC, Montimurro JS, Zabetian CP, Payami H. · Applied Statistics Laboratory, General Electric Global Research Center, Niskayuna, NY, USA. · Hum Genet. · Pubmed #18210157 No free full text.

Abstract: The objective of this study was to explore combined effects of four candidate susceptibility genes and two exposures on Parkinson's disease (PD) risk; namely, alpha-synuclein (SNCA) promoter polymorphism REP1, microtubule-associated protein tau (MAPT) H1/H2 haplotypes, apolipoprotein E (APOE) epsilon2/epsilon3/epsilon4 polymorphism, ubiquitin carboxy-terminal esterase L1 (UCHL1) S18Y variant, cigarette smoking and caffeinated coffee consumption. 932 PD patients and 664 control subjects from the NeuroGenetics Research Consortium, with complete data on all six factors, were studied. Uniform protocols were used for diagnosis, recruitment, data collection and genotyping. A logistic regression model which included gene-exposure interactions was applied. Likelihood ratio tests (LRTs) were used for significance testing and Bayesian inference was used to estimate odds ratios (ORs). MAPT (P = 0.007), SNCA REP1 (P = 0.012), smoking (P = 0.001), and coffee (P = 0.011) were associated with PD risk. Two novel interactions were detected: APOE with coffee (P = 0.005), and REP1 with smoking (P = 0.021). While the individual main effects were modest, each yielding OR < 1.6, the effects were cumulative, with some combinations reaching OR = 12.6 (95% CI: 5.9-26.8). This study provides evidence for the long-held notion that PD risk is modulated by cumulative and interactive effects of genes and exposures. Furthermore, the study demonstrates that while interaction studies are useful for exploring risk relationships that might otherwise go undetected, results should be interpreted with caution because of the inherent loss of power due to multiple testing. The novel findings of this study that warrant replication are the evidence for interaction of coffee with APOE, and of smoking with REP1 on PD risk.

Hutter CM, Samii A, Factor SA, Nutt JG, Higgins DS, Bird TD, Griffith A, Roberts JW, Leis BC, Montimurro JS, Kay DM, Edwards KL, Payami H, Zabetian CP. · Department of Epidemiology, University of Washington, Seattle, WA, USA. · Eur J Neurol. · Pubmed #18093156 No free full text.

Abstract: UCHL1 has been proposed as a candidate gene for Parkinson's disease (PD). A meta-analysis of white and Asian subjects reported an inverse association between the non-synonymous UCHL1 S18Y polymorphism and PD risk. However, this finding was not replicated in a large case-control study and updated meta-analysis restricted to white subjects. We performed a case-control study of 1757 PD patients recruited from movement disorder clinics and 2016 unrelated controls from four regions of the United States. All subjects self-reported as white. We did not observe evidence for an association between S18Y genotypes and PD (overall P-value for association: P = 0.42). After adjustment for age, sex, and recruitment region, the odds ratio for Y/S versus S/S was 0.91 (95% CI: 0.78-1.06) and for Y/Y versus S/S was 0.87 (95% CI: 0.58-1.29). We also did not observe a significant association for recessive or dominant models of inheritance, or after stratification by age at onset, age at blood draw, sex, family history of PD, or recruitment region. Our results suggest that UCHL1 S18Y is not a major susceptibility factor for PD in white populations although we cannot exclude the possibility that the S18Y variant exerts weak effects on risk, particularly in early-onset disease.

Esper CD, Factor SA. · Department of Neurology, Emory University School of Medicine, Atlanta, Georgia 30329, USA. · Mov Disord. · Pubmed #18067180 No free full text.

Abstract: Our objective was to evaluate the ability of neurologists to recognize and diagnose drug-induced Parkinsonism (DIP) in the elderly. DIP is a diagnostic challenge because it can be indistinguishable from Parkinson's disease, especially in the elderly. It is frequently under-recognized by psychiatrists and primary care physicians. Atypical antipsychotics (AA) are advertised for their low propensity to cause DIP. This may add to problems with recognition. We performed a retrospective record review of consecutive new parkinsonian patients seen over 2 years in a movement disorders clinic to examine the frequency, causative agents, and diagnostic accuracy of DIP by physicians, particularly neurologists. Of 354 Parkinsonian patients evaluated, 24 (6.8%) had DIP, 46% of these were due to AA and 29% were caused by metoclopramide. Of the 24 patients with DIP, only one was previously diagnosed accurately according to records. Nineteen patients (79%) were previously evaluated by a neurologist, and none of them was diagnosed with DIP. The primary reason for failure to recognize DIP relates to under-recognition of AA as possible cause. A majority remained on the inciting agents while dopaminergic drugs were prescribed. DIP was reversible when the inciting drug was stopped. DIP is a common form of parkinsonism and is under-recognized, even by neurologists. AA and metoclopramide do not appear to be well-known to cause DIP. Cessation of the offending agent results in improvement of symptoms and would eliminate the need for dopaminergic agents, which are known to commonly cause side effects in the elderly.

Powers KM, Kay DM, Factor SA, Zabetian CP, Higgins DS, Samii A, Nutt JG, Griffith A, Leis B, Roberts JW, Martinez ED, Montimurro JS, Checkoway H, Payami H. · Department of Environmental and Occupational Health Sciences, School of Public Health and Community Medicine, University of Washington, Seattle, Washington, USA. · Mov Disord. · Pubmed #17987647 No free full text.

Abstract: Inverse associations of Parkinson's disease (PD) with cigarette smoking, coffee drinking, and nonsteroidal anti-inflammatory drug (NSAID) use have been reported individually, but their joint effects have not been examined. To quantify associations with PD for the individual, two-way and three-way combinations of these factors, a case-control association study with 1,186 PD patients and 928 controls was conducted. The study setting was the NeuroGenetics Research Consortium. Subjects completed a structured questionnaire regarding smoking, coffee, and NSAID consumption. Odds ratios were calculated using unconditional logistic regression. Smoking, coffee, and over the counter NSAID use as individual factors exhibited significantly reduced risks of 20% to 30%. The two-way and three-way combinations were associated with risk reduction of 37% to 49%, and 62%, respectively. Smoking and coffee exhibited significant inverse risk trends with increasing cumulative exposures, suggesting dose-response relations. With respect to the combination of all three exposures, persons who were at the highest exposure strata for smoking and coffee and used NSAIDs had an estimated 87% reduction in risk (OR = 0.13, 95% CI = 0.06-0.29). Whether this finding reflects true biologic protection needs to be investigated.

Rosen AR, Steenland NK, Hanfelt J, Factor SA, Lah JJ, Levey AI. · Department of Neurology, Emory University, 1841 Clifton Rd, Atlanta, GA 30329, USA. · Neurogenetics. · Pubmed #17805588 links to  free full text

Abstract: This case-control study examined the potential for a common etiology of Parkinson's disease (PD) and Alzheimer's disease (AD) using reported family history. Structured interviews were used to collect AD and PD family history from subjects (n = 1,531) with AD, PD, AD/PD, or controls. Intergroup analysis compared reported AD and PD family histories in the three case groups to the histories reported in the control group. Intragroup analysis stratified each diagnostic group based on positive family history of AD, then compared the subgroups for a family history of PD. Subjects with AD had a higher risk of having a family history of AD [odds ratio (OR) 2.3; 1.5-3.4] and subjects with PD had a higher risk of having a family history of PD (OR 2.2; 1.2-4.0) as compared to control subjects. Intergroup analyses revealed no significant crossed risk, increased risk of subjects with AD having a family history of PD vs controls and vice versa. Intragroup analysis found that subjects with PD and a family history of AD were more likely to have a family history of PD (OR 1.7; 1.1-2.6) when compared to subjects with PD and no family history of AD. A similar trend was found for subjects with AD (OR 1.7; 0.9-3.1). AD and PD cases each have an increased familial risk of their respective disease. Probands with AD or PD and a family history of either disease have a higher crossed risk of a family history of the other disease. These findings suggest the existence of common genetic and/or environmental factors that predispose to both AD and PD in the subset of cases with positive family history of both neurodegenerative diseases.

Zabetian CP, Hutter CM, Factor SA, Nutt JG, Higgins DS, Griffith A, Roberts JW, Leis BC, Kay DM, Yearout D, Montimurro JS, Edwards KL, Samii A, Payami H. · Geriatric Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA 98108, USA. · Ann Neurol. · Pubmed #17514749 No free full text.

Abstract: OBJECTIVE: An inversion polymorphism of approximately 900 kb on chromosome 17q21, which includes the microtubule-associated protein tau (MAPT) gene defines two haplotype clades, H1 and H2. Several small case-control studies have observed a marginally significant excess of the H1/H1 diplotype among patients with Parkinson's disease (PD), and one reported refining the association to a region spanning exons 1 to 4 of MAPT. We sought to replicate these findings. METHODS: We genotyped 1,762 PD patients and 2,010 control subjects for a single nucleotide polymorphism (SNP) that differentiates the H1 and H2 clades. We also analyzed four SNPs that define subhaplotypes within H1 previously reported to associate with PD or other neurodegenerative disorders. RESULTS: After adjusting for age, sex, and site, we observed a robust association between the H1/H1 diplotype and PD risk (odds ratio for H1/H1 vs H1/H2 and H2/H2, 1.46; 95% confidence interval, 1.25-1.69; p = 8 x 10(-7)). The effect was evident in both familial and sporadic subgroups, men and women, and early- and late-onset disease. Within H1/H1 individuals, there was no significant difference between cases and control subjects in the overall frequency distribution of H1 subhaplotypes. INTERPRETATION: Our data provide strong evidence that the H1 clade, which contains MAPT and several other genes, is a risk factor for PD. However, attributing this finding to variants within a specific region of MAPT is premature. Thorough fine-mapping of the H1 clade in large numbers of individuals is now needed to identify the underlying functional variant(s) that alter susceptibility for PD.

Kay DM, Moran D, Moses L, Poorkaj P, Zabetian CP, Nutt J, Factor SA, Yu CE, Montimurro JS, Keefe RG, Schellenberg GD, Payami H. · Wadsworth Center, New York State Department of Health, Albany, NY 12201-2002, USA. · Ann Neurol. · Pubmed #17187375 No free full text.

Abstract: OBJECTIVE: Homozygous or compound heterozygous parkin mutations cause juvenile parkinsonism. Heterozygous parkin mutations are also found in patients with typical Parkinson's disease (PD), but it is unclear whether a single "mutation" in a patient is related to disease or is coincidental, because the mutation frequency in control subjects is unknown. We present a comprehensive sequence analysis of parkin in control subjects. METHODS: A total of 302 patients and 301 control subjects were sequenced, and findings were replicated in 1,260 additional patients and 1,657 control subjects. RESULTS: Thirty-four variants were detected, of which 21 were novel; 12 were polymorphisms and 22 were rare variants. Patients and control subjects did not differ in the frequency, type, or functional location of the variants. Even P437L, a common mutation thought to be pathogenic, was present in unaffected control subjects. INTERPRETATION: parkin point mutations are not exclusive to PD. The mere presence of a single point mutation in a patient, in the absence of a second mutation, should not be taken as a cause of disease unless corroborated by family data and functional studies. This study does not support the notion that heterozygous parkin sequence variants (mutations or polymorphisms) are risk factors for PD. Whether heterozygous dosage anomalies are associated with PD remains to be determined.

Elbaz A, Nelson LM, Payami H, Ioannidis JP, Fiske BK, Annesi G, Carmine Belin A, Factor SA, Ferrarese C, Hadjigeorgiou GM, Higgins DS, Kawakami H, Krüger R, Marder KS, Mayeux RP, Mellick GD, Nutt JG, Ritz B, Samii A, Tanner CM, Van Broeckhoven C, Van Den Eeden SK, Wirdefeldt K, Zabetian CP, Dehem M, Montimurro JS, Southwick A, Myers RM, Trikalinos TA. · INSERM, Unit 708, Paris, France. · Lancet Neurol. · Pubmed #17052658 No free full text.

Abstract: BACKGROUND: A genome-wide association study identified 13 single-nucleotide polymorphisms (SNPs) significantly associated with Parkinson's disease. Small-scale replication studies were largely non-confirmatory, but a meta-analysis that included data from the original study could not exclude all SNP associations, leaving relevance of several markers uncertain. METHODS: Investigators from three Michael J Fox Foundation for Parkinson's Research-funded genetics consortia-comprising 14 teams-contributed DNA samples from 5526 patients with Parkinson's disease and 6682 controls, which were genotyped for the 13 SNPs. Most (88%) participants were of white, non-Hispanic descent. We assessed log-additive genetic effects using fixed and random effects models stratified by team and ethnic origin, and tested for heterogeneity across strata. A meta-analysis was undertaken that incorporated data from the original genome-wide study as well as subsequent replication studies. FINDINGS: In fixed and random-effects models no associations with any of the 13 SNPs were identified (odds ratios 0.89 to 1.09). Heterogeneity between studies and between ethnic groups was low for all SNPs. Subgroup analyses by age at study entry, ethnic origin, sex, and family history did not show any consistent associations. In our meta-analysis, no SNP showed significant association (summary odds ratios 0.95 to 1.08); there was little heterogeneity except for SNP rs7520966. INTERPRETATION: Our results do not lend support to the finding that the 13 SNPs reported in the original genome-wide association study are genetic susceptibility factors for Parkinson's disease.