E D Louis
Affiliation: Columbia University
- Louis E, Moskowitz C, Friez M, Amaya M, Vonsattel J. Parkinsonism, dysautonomia, and intranuclear inclusions in a fragile X carrier: a clinical-pathological study. Mov Disord. 2006;21:420-5 pubmed..Further studies of clinical-pathological correlation in a larger sample of brains would provide additional insight into the mechanisms of the tremor, ataxia, and parkinsonism in these patients. ..
- Louis E, Rios E, Henchcliffe C. How are we doing with the treatment of essential tremor (ET)?: Persistence of patients with ET on medication: data from 528 patients in three settings. Eur J Neurol. 2010;17:882-4 pubmed publisher..These data make tangibly evident that there is a sizable population of patients with ET who are untreated and disabled, and underscore the inadequacy of current pharmacotherapeutic options for this common neurological disease. ..
- Louis E, Frucht S. Prevalence of essential tremor in patients with Parkinson's disease vs. Parkinson-plus syndromes. Mov Disord. 2007;22:1402-7 pubmed..Patients with PD were three to thirteen times more likely to have diagnoses of ET than were patients with Parkinson-plus syndromes. These data further confirm the link between ET and PD, and possibly, between ET and Lewy body disease. ..
- Louis E, Faust P, Vonsattel J, Honig L, Henchcliffe C, Pahwa R, et al. Older onset essential tremor: More rapid progression and more degenerative pathology. Mov Disord. 2009;24:1606-12 pubmed publisher..In a brain bank, older age of onset was associated with more degenerative pathology in the cerebellum. As in several neurodegenerative disorders, in older onset cases, it is possible that the disease advances more rapidly. ..
- Louis E, Garcia W, Rauh V. Tremor in a population-based cohort of children in New York City. Pediatr Neurol. 2015;52:187-91 pubmed publisher..It also lessens with advancing age. Rather than an isolated finding, tremor was associated with other measures of poorer motor hand function. ..
- Louis E, Ford B, Frucht S. Factors associated with increased risk of head tremor in essential tremor: a community-based study in northern Manhattan. Mov Disord. 2003;18:432-6 pubmed..These disease associations require further exploration, and might provide insight into the mechanisms underlying head tremor. ..
- Louis E, Benito Leon J, Bermejo Pareja F. Population-based prospective study of cigarette smoking and risk of incident essential tremor. Neurology. 2008;70:1682-7 pubmed publisher..29, 95% CI 0.09-0.90, p = 0.03 [adjusted model]). We demonstrated an association between baseline heavy cigarette smoking and lower risk of incident essential tremor. The biologic basis for this association requires future investigation. ..
- Louis E, Bromley S, Jurewicz E, Watner D. Olfactory dysfunction in essential tremor: a deficit unrelated to disease duration or severity. Neurology. 2002;59:1631-3 pubmed..Mean score was lower in cases than in control subjects (29.0 +/- 6.1 vs 31.9 +/- 4.6, p = 0.02) and was not correlated with tremor severity or duration. ..
- Louis E, Shungu D, Chan S, Mao X, Jurewicz E, Watner D. Metabolic abnormality in the cerebellum in patients with essential tremor: a proton magnetic resonance spectroscopic imaging study. Neurosci Lett. 2002;333:17-20 pubmed..59, P = 0.02). The reduction in cerebellar cortical NAA/tCR indicates that there is neuronal damage or loss in ET, suggesting that ET may be a neurodegenerative disease. ..
- Louis E, Benito Leon J, Bermejo Pareja F. Antihypertensive agents and risk of Parkinson's disease, essential tremor and dementia: a population-based prospective study (NEDICES). Neuroepidemiology. 2009;33:286-92 pubmed publisher..63, p = 0.06) but was not associated with reduced risk of incident dementia (RR(adjusted) = 1.02, p = 0.95). We did not find evidence of a protective effect of antihypertensive medications in these three neurodegenerative disorders. ..
- Louis E, Dogu O. Isolated head tremor: part of the clinical spectrum of essential tremor? Data from population-based and clinic-based case samples. Mov Disord. 2009;24:2281-5 pubmed publisher..Head tremor in the complete absence of arm tremor was not observed in any cases (0.0%). These clinical data may be of value to clinicians in practice settings and researchers in phenotyping efforts in the emerging field of ET genetics. ..
- Louis E, Benito LeÃ³n J, Moreno GarcÃa S, Vega S, Romero J, Bermejo Pareja F, et al. Blood harmane (1-methyl-9H-pyrido[3,4-b]indole) concentration in essential tremor cases in Spain. Neurotoxicology. 2013;34:264-8 pubmed publisher..These data seem to further extend our observations from New York to a second cohort of ET cases in Spain. This neurotoxin continues to be a source of interest for future confirmatory research. ..
- Louis E, Factor Litvak P, Gerbin M, Slavkovich V, Graziano J, Jiang W, et al. Blood harmane, blood lead, and severity of hand tremor: evidence of additive effects. Neurotoxicology. 2011;32:227-32 pubmed publisher..Given the very high population prevalence of tremor disorders, identifying environmental determinants is important for primary disease prevention. ..
- Louis E. Medication non-adherence in essential tremor. Parkinsonism Relat Disord. 2015;21:138-41 pubmed publisher..It is possible that this relatively high rate of non-adherence could be a function of the poor therapeutic efficacy of the medications currently available to treat ET. ..
- Louis E, Hernandez N, Alcalay R, Tirri D, Ottman R, Clark L. Prevalence and features of unreported dystonia in a family study of "pure" essential tremor. Parkinsonism Relat Disord. 2013;19:359-62 pubmed publisher..The overarching biological issue is whether ET and dystonia should be regarded as one disease or two; this has obvious implications for the structuring of analyses in genetic studies. ..
- Louis E. Clinical practice. Essential tremor. N Engl J Med. 2001;345:887-91 pubmed
- Louis E, Faust P, Vonsattel J, Honig L, Rajput A, Rajput A, et al. Torpedoes in Parkinson's disease, Alzheimer's disease, essential tremor, and control brains. Mov Disord. 2009;24:1600-5 pubmed publisher..Although torpedoes are increased in AD and PD, as well as cerebellar ET, the magnitude of increase in cerebellar ET is greater, and cannot be accounted for by concomitant AD or PD pathology. ..
- Louis E, Rios E. Embarrassment in essential tremor: prevalence, clinical correlates and therapeutic implications. Parkinsonism Relat Disord. 2009;15:535-8 pubmed publisher..The majority of clinical trials do not assess the therapeutic effects of medication on embarrassment. These trials may benefit from scaled assessments of level of embarrassment. ..
- Louis E, Fried L, Fitzpatrick A, Longstreth W, Newman A. Regional and racial differences in the prevalence of physician-diagnosed essential tremor in the United States. Mov Disord. 2003;18:1035-40 pubmed..Caucasians were five times more likely to have physician-diagnosed ET than were African Americans. This study does not provide an explanation for this difference, which deserves further study. ..
- Louis E, Benito Leon J, Bermejo Pareja F. Population-based study of baseline ethanol consumption and risk of incident essential tremor. J Neurol Neurosurg Psychiatry. 2009;80:494-7 pubmed publisher..Ethanol is often used for symptomatic relief; studies should explore whether higher consumption levels are a continued source of underlying cerebellar neurotoxicity in patients who already manifest this disease. ..
- Louis E, Vonsattel J, Honig L, Ross G, Lyons K, Pahwa R. Neuropathologic findings in essential tremor. Neurology. 2006;66:1756-9 pubmed..Six cases (60%) had Lewy bodies vs 2 controls (16.7%) (odds ratio 7.5, 95% CI 1.04 to 54.1; p = 0.035). Four of these six had an atypical distribution of brainstem Lewy bodies. ET may be pathologically heterogeneous. ..
- Louis E, Faust P, Ma K, Yu M, Cortes E, Vonsattel J. Torpedoes in the cerebellar vermis in essential tremor cases vs. controls. Cerebellum. 2011;10:812-9 pubmed publisher..These data further confirm the central role of the cerebellum in the underlying pathophysiology of this common neurological disorder. ..
- ..More recent postmortem studies have helped localize the possible source of ET to structural alterations in the cerebellum and its connecting pathways. ..
- Louis E, Hafeman D, Parvez F, Liu X, Alcalay R, Islam T, et al. Tremor severity and age: a cross-sectional, population-based study of 2,524 young and midlife normal adults. Mov Disord. 2011;26:1515-20 pubmed publisher..These data suggest that age-dependent increase in tremor amplitude is not restricted to older people but occurs in all adult age groups. ..
- Louis E, Benito Leon J, Ottman R, Bermejo Pareja F. A population-based study of mortality in essential tremor. Neurology. 2007;69:1982-9 pubmed..69 (95% CI = 2.18 to 10.07, p = 0.001). In this longitudinal, prospective study, the risk of mortality was increased in essential tremor. Additional studies of incident cases are needed to confirm these results. ..
- Louis E, Benito Leon J, Vega Quiroga S, Bermejo Pareja F. Cognitive and motor functional activity in non-demented community-dwelling essential tremor cases. J Neurol Neurosurg Psychiatry. 2010;81:997-1001 pubmed publisher..Lower cognitive test scores were associated with more reported functional difficulty, indicating that lower cognitive test scores in ET, rather than being inconsequential, have a clear clinical-functional correlate. ..
- Louis E, Mazzoni P, Ma K, Moskowitz C, Lawton A, Garber A, et al. Essential tremor with ubiquitinated intranuclear inclusions and cerebellar degeneration. Clin Neuropathol. 2012;31:119-26 pubmed..This case further reinforces the view that ET is likely to be a heterogeneous family of degenerative diseases whose underlying pathological anatomy involves the cerebellum. ..
- Louis E, Benito Leon J, Vega S, Bermejo Pareja F. Frailty in elderly persons with essential tremor: a population-based study (NEDICES). Eur J Neurol. 2011;18:1251-7 pubmed publisher..Whether this increased frailty is a contributor to the increased risk of mortality that has been observed in some studies is a question that deserves further scrutiny. ..
- Louis E, Dogu O. Does age of onset in essential tremor have a bimodal distribution? Data from a tertiary referral setting and a population-based study. Neuroepidemiology. 2007;29:208-12 pubmed..By contrast, in a tertiary referral center, age of onset was clearly bimodal. While age of ET onset is often said to be bimodal, this may be due to the preferential referral to tertiary centers of patients with young-onset, familial ET. ..
- Louis E. Essential tremors: a family of neurodegenerative disorders?. Arch Neurol. 2009;66:1202-8 pubmed publisher..Furthermore, this aging-associated, progressive disorder is associated with neuronal loss and postmortem changes that occur in traditional neurodegenerative disorders. ..
- Louis E. Essential tremor as a neuropsychiatric disorder. J Neurol Sci. 2010;289:144-8 pubmed publisher..Further study of these non-motor phenomena will advance our understanding of disease mechanisms and enhance the quality of clinical interactions with patients. ..
- Louis E, Zheng W, Jurewicz E, Watner D, Chen J, Factor Litvak P, et al. Elevation of blood beta-carboline alkaloids in essential tremor. Neurology. 2002;59:1940-4 pubmed..71 +/- 0.50 g(-10)/mL) an affected relative (p = 0.83). Blood concentrations of harmane were measured in ET cases compared with controls. Concentrations were elevated in cases with and without a family history of ET. ..
- Louis E, Honig L, Vonsattel J, Maraganore D, Borden S, Moskowitz C. Essential tremor associated with focal nonnigral Lewy bodies: a clinicopathologic study. Arch Neurol. 2005;62:1004-7 pubmed..This study provides support for the link between essential tremor and LB disease and raises the question as to what proportion of patients with essential tremor might have unusual forms of LB disease. ..
- Louis E, Borden S, Moskowitz C. Essential tremor centralized brain repository: diagnostic validity and clinical characteristics of a highly selected group of essential tremor cases. Mov Disord. 2005;20:1361-5 pubmed
- Louis E, Benito Leon J, Vega Quiroga S, Bermejo Pareja F. Faster rate of cognitive decline in essential tremor cases than controls: a prospective study. Eur J Neurol. 2010;17:1291-7 pubmed publisher..This study provides evidence that cognitive deficits in ET are not static, and they appear to be progressing at a faster rate than in elders without this disease. ..
- Louis E, Babij R, Ma K, Cortes E, Vonsattel J. Essential tremor followed by progressive supranuclear palsy: postmortem reports of 11 patients. J Neuropathol Exp Neurol. 2013;72:8-17 pubmed publisher..e. et + psp). ..
- Louis E. Whipple disease. Curr Neurol Neurosci Rep. 2003;3:470-5 pubmed..Although the organism historically has been difficult to culture, several recent attempts have been successful. Antibiotic treatment is recommended for 1 year while monitoring the clinical signs and cerebrospinal fluid PCR results. ..
- Louis E, Benito Leon J, Bermejo Pareja F. Self-reported depression and anti-depressant medication use in essential tremor: cross-sectional and prospective analyses in a population-based study. Eur J Neurol. 2007;14:1138-46 pubmed..Rather than being totally benign, ET seems to be associated with a mood disorder. Furthermore, as well as being a secondary response to disease manifestations, this mood disorder may be a primary feature of the underlying disease. ..
- Louis E, Rios E, Pellegrino K, Jiang W, Factor Litvak P, Zheng W. Higher blood harmane (1-methyl-9H-pyrido[3,4-b]indole) concentrations correlate with lower olfactory scores in essential tremor. Neurotoxicology. 2008;29:460-5 pubmed publisher..12, p=0.32). Blood harmane concentrations were correlated with UPSIT scores in ET cases but not controls. These analyses set the stage for postmortem studies to further explore the role of harmane as a cerebellar toxin in ET. ..
- Louis E, Applegate L, Rios E. ICD-9 CM code 333.1 as an identifier of patients with essential tremor: a study of the positive predictive value of this code. Neuroepidemiology. 2007;28:181-5 pubmed..6 vs. 51.9%, OR 0.50, 95% CI 0.23-0.70, p < 0.001). The code 333.1 performed poorly when attempting to identify ET cases. Given the very high prevalence of ET, a unique diagnostic code would seem to be in order. ..
- Louis E, Yi H, Erickson Davis C, Vonsattel J, Faust P. Structural study of Purkinje cell axonal torpedoes in essential tremor. Neurosci Lett. 2009;450:287-91 pubmed publisher..It is not known where in the pathogenic cascade these accumulations occur (i.e., whether these accumulations are the primary event or a secondary/downstream event) and this deserves further study. ..
- Lee M, Cheng M, Lin C, Louis E, Faust P, Kuo S. Decreased EAAT2 protein expression in the essential tremor cerebellar cortex. Acta Neuropathol Commun. 2014;2:157 pubmed publisher..Our main finding, a significant reduction in cerebellar cortical EAAT2 protein levels in essential tremor, suggests that Purkinje cells in essential tremor might be more vulnerable to excitotoxic damage than those of controls. ..
- Louis E, Marder K, Tabert M, Devanand D. Mild Parkinsonian signs are associated with lower olfactory test scores in the community-dwelling elderly. Mov Disord. 2008;23:524-30 pubmed..MPS were associated with a mild reduction in olfactory function. These observations further support the view of MPS as a marker of emerging degenerative brain pathologies. ..
- Louis E. Weir Mitchell's 1859 demonstration of "a peculiar contraction" produced by a percussion hammer. Neurology. 2008;70:969-73 pubmed publisher..Mitchell viewed the phenomenon as a local muscle response. While the concepts that later allowed Erb to correctly interpret the phenomenon as a reflex arc were already in place, Mitchell did not synthesize these concepts. ..
- Louis E. Re-thinking the biology of essential tremor: from models to morphology. Parkinsonism Relat Disord. 2014;20 Suppl 1:S88-93 pubmed publisher..This shift in paradigm opens the door for research that aims to identify the primary set of molecular triggers and the cascade of molecular/cellular events that accompany this disease. ..
- Louis E. Essential tremor: evolving clinicopathological concepts in an era of intensive post-mortem enquiry. Lancet Neurol. 2010;9:613-22 pubmed publisher..However, with more controlled, tissue-based studies being done, it is hoped that these mechanisms will be elucidated, thereby laying the foundation for the development of more targeted, effective pharmacotherapeutic interventions. ..
- Louis E, Benito Leon J, Bermejo Pareja F. Philadelphia Geriatric Morale Scale in essential tremor: a population-based study in three Spanish communities. Mov Disord. 2008;23:1435-40 pubmed publisher..This lower morale could in part be a proxy for mild, untreated depression. It therefore seems important to detect and then possibly treat this problem to improve the psychological well-being of patients with this disease. ..
- Louis E, Agnew A, GILLMAN A, Gerbin M, Viner A. Estimating annual rate of decline: prospective, longitudinal data on arm tremor severity in two groups of essential tremor cases. J Neurol Neurosurg Psychiatry. 2011;82:761-5 pubmed publisher..1% and 5.3% and the median annual increase from baseline was between 1.8% and 2.0%. These published estimates will hopefully be a useful prognostic guide for clinicians and their patients. ..
- Louis E, Asabere N, Agnew A, Moskowitz C, Lawton A, Cortes E, et al. Rest tremor in advanced essential tremor: a post-mortem study of nine cases. J Neurol Neurosurg Psychiatry. 2011;82:261-5 pubmed publisher..These data support the notion that isolated rest tremor in longstanding ET is not the expression of underlying Lewy body pathology in the SNc. ..
- Louis E, Applegate L, Graziano J, Parides M, Slavkovich V, Bhat H. Interaction between blood lead concentration and delta-amino-levulinic acid dehydratase gene polymorphisms increases the odds of essential tremor. Mov Disord. 2005;20:1170-7 pubmed..The presence of increased circulating BPb concentrations along with a greater potential for lead toxicity (ALAD-2 allele) could result in greater cerebellar damage, thereby increasing the risk of developing tremor. ..
- Louis E, GILLMAN A, Boschung S, Hess C, Yu Q, Pullman S. High width variability during spiral drawing: further evidence of cerebellar dysfunction in essential tremor. Cerebellum. 2012;11:872-9 pubmed publisher..16, p=0.06). The primary anatomical substrate for ET continues to be a matter of speculation, yet these and other clinical data lend support to the notion that there is an underlying abnormality of the cerebellum and/or its pathways. ..
- Louis E, Zheng W, Applegate L, Shi L, Factor Litvak P. Blood harmane concentrations and dietary protein consumption in essential tremor. Neurology. 2005;65:391-6 pubmed..Whether this difference is due to greater animal protein consumption by patients or their failure to metabolize harmane is unknown...
- Louis E, Williams M. A biography of James Ramsay Hunt (1874-1937). J Hist Neurosci. 2003;12:266-75 pubmed
- Louis E, Tang M, Schupf N. Mild parkinsonian signs are associated with increased risk of dementia in a prospective, population-based study of elders. Mov Disord. 2010;25:172-8 pubmed publisher..Baseline MPS seems to be a predictor of incident dementia. These motor signs might, therefore, serve as a useful biomarker for emerging dementia...