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Bakels HS, Feleus S, Rodríguez-Girondo M, Losekoot M, Bijlsma EK, Roos RAC, de Bot ST. Prevalence of Juvenile-Onset and Pediatric Huntington's Disease and Their Availability and Ability to Participate in Trials: A Dutch Population and Enroll-HD Observational Study. J Huntingtons Dis 2024:JHD240034. [PMID: 39121132 DOI: 10.3233/jhd-240034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/11/2024]
Abstract
Background Juvenile-onset Huntington's disease (JHD) represents 1-5% of Huntington's disease (HD) patients, with onset before the age of 21. Pediatric HD (PHD) relates to a proportion of JHD patients that is still under 18 years of age. So far, both populations have been excluded from interventional trials. Objective Describe the prevalence and incidence of JHD and PHD in the Netherlands and explore their ability to participate in interventional trials. Methods The prevalence and incidence of PHD and JHD patients in the Netherlands were analyzed. In addition, we explored proportions of JHD patients diagnosed at pediatric versus adult age, their diagnostic delay, and functional and modelled (CAP100) disease stage in JHD and adult-onset HD patients at diagnosis. Results The prevalence of JHD and PHD relative to the total manifest HD population in January 2024 was between 0.84-1.25% and 0.09-0.14% respectively. The mean incidence of JHD patients being diagnosed was between 0.85-1.28 per 1000 patient years and of PHD 0.14 per 1.000.000 under-aged person years. 55% of JHD cases received a clinical diagnosis on adult age. At diagnosis, the majority of JHD patients was functionally compromised and adolescent-onset JHD patients were significantly less independent compared to adult-onset HD patients. Conclusions In the Netherlands, the epidemiology of JHD and PHD is lower than previously suggested. More than half of JHD cases are not eligible for trials in the PHD population. Furthermore, higher functional dependency in JHD patients influences their ability to participate in trials. Lastly, certain UHDRS functional assessments and the CAP100 score do not seem appropriate for this particular group.
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Affiliation(s)
- Hannah S Bakels
- Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Stephanie Feleus
- Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands
- Department of Clinical Epidemiology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Mar Rodríguez-Girondo
- Department of Biomedical Data Sciences, Leiden University Medical Centre, Leiden, The Netherlands
| | - Monique Losekoot
- Department of Clinical Genetics, Leiden University Medical Centre, Leiden, The Netherlands
| | - Emilia K Bijlsma
- Department of Clinical Genetics, Leiden University Medical Centre, Leiden, The Netherlands
| | - Raymund A C Roos
- Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Susanne T de Bot
- Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands
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The Comprehensive Analysis of Motor and Neuropsychiatric Symptoms in Patients with Huntington's Disease from China: A Cross-Sectional Study. J Clin Med 2022; 12:jcm12010206. [PMID: 36615008 PMCID: PMC9821667 DOI: 10.3390/jcm12010206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/23/2022] [Accepted: 12/23/2022] [Indexed: 12/30/2022] Open
Abstract
Huntington’s disease (HD) is an autosomal dominant inherited neurodegenerative disorder caused by CAG repeats expansion. There is a paucity of comprehensive clinical analysis in Chinese HD patients due to the low prevalence of HD in Asia. We aimed to comprehensively describe the motor, neuropsychiatric symptoms, and functional assessment in patients with HD from China. A total of 205 HD patients were assessed by the Unified Huntington’s Disease Rating Scale (UHDRS), the short version of Problem-Behavior Assessment (PBA-s), Hamilton Depression Scale (HAMD) and Beck Depression Inventory (BDI). Multivariate logistic regression analysis was used to explore the independent variables correlated with neuropsychiatric subscales. The mean age of motor symptom onset was 41.8 ± 10.0 years old with a diagnostic delay of 4.3 ± 3.8 years and a median CAG repeats of 44. The patients with a positive family history had a younger onset and larger CAG expansion than the patients without a family history (p < 0.05). There was a significant increase in total motor score across disease stages (p < 0.0001). Depression (51%) was the most common neuropsychiatric symptom at all stages, whereas moderate to severe apathy commonly occurred in advanced HD stages. We found lower functional capacity and higher HAMD were independently correlated with irritability; higher HAMD and higher BDI were independently correlated with affect; male sex and higher HAMD were independently correlated with apathy. In summary, comprehensive clinical profile analysis of Chinese HD patients showed not only chorea-like movement, but psychiatric symptoms were outstanding problems and need to be detected early. Our study provides the basis to guide clinical practice, especially in practical diagnostic and management processes.
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Huntington's Chorea-a Rare Neurodegenerative Autosomal Dominant Disease: Insight into Molecular Genetics, Prognosis and Diagnosis. Appl Biochem Biotechnol 2021; 193:2634-2648. [PMID: 34235640 DOI: 10.1007/s12010-021-03523-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 01/27/2021] [Indexed: 12/24/2022]
Abstract
Huntington's disease is a neurodegenerative autosomal disease results due to expansion of polymorphic CAG repeats in the huntingtin gene. Phosphorylation of the translation initiation factor 4E-BP results in the alteration of the translation control leading to unwanted protein synthesis and neuronal function. Consequences of mutant huntington (mhtt) gene transcription are not well known. Variability of age of onset is an important factor of Huntington's disease separating adult and juvenile types. The factors which are taken into account are-genetic modifiers, maternal protection i.e excessive paternal transmission, superior ageing genes and environmental threshold. A major focus has been given to the molecular pathogenesis which includes-motor disturbance, cognitive disturbance and neuropsychiatric disturbance. The diagnosis part has also been taken care of. This includes genetic testing and both primary and secondary symptoms. The present review also focuses on the genetics and pathology of Huntington's disease.
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Li HL, Li XY, Dong Y, Zhang YB, Cheng HR, Gan SR, Liu ZJ, Ni W, Burgunder JM, Yang XW, Wu ZY. Clinical and Genetic Profiles in Chinese Patients with Huntington's Disease: A Ten-year Multicenter Study in China. Aging Dis 2019; 10:1003-1011. [PMID: 31595198 PMCID: PMC6764736 DOI: 10.14336/ad.2018.0911] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 09/11/2018] [Indexed: 11/05/2022] Open
Abstract
Huntington’s disease (HD) is an autosomal dominant inherited neurodegenerative disorder caused by CAG triplet repeats expansion in exon 1 of the Huntingtin gene (HTT). In China, HD is considered to have a low prevalence. The goal of this study was to describe the clinical characteristic and genetic profiles of HD in a Chinese cohort. A total of 322 individuals with expanded CAG repeats were consecutively recruited from the neurologic clinics of three medical centers in Southeastern China between 2008 and 2018. Among them, 80 were pre-symptomatic mutation carriers and 242 were symptomatic patients. The mean age at onset (AAO), defined here as the age at motor symptom onset, of the 242 manifest HD individuals was 40.3 ± 11.9 years and the mean CAG repeat length was 46.1 ± 7.5 in the group of symptomatic patients. Initial symptoms were abnormal movements in 88.8% of the patients with psychiatric symptoms in 6.2%, cognitive impairment in 3.3% and others in 1.7%. The AAO of motor was negatively correlated with the CAG repeat length in an exponential regression analysis (R 2 = 0.74, P<0.001). Analysis of 46 parent-child pairs showed that the CAG repeat length was longer in the offspring group (45.8 ±7.6) than in the parent group (43.8 ±3.0) (p=0.005). Overall, this study provides clinical and genetic profiles in a cohort of Chinese patients with HD, which should contribute to a better understanding of this disorder.
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Affiliation(s)
- Hong-Lei Li
- 1Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiao-Yan Li
- 1Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China
| | - Yi Dong
- 1Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China
| | - Yan-Bin Zhang
- 2Department of Neurology, First Affiliated Hospital, Fujian Medical University, Fuzhou, China
| | - Hong-Rong Cheng
- 1Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China
| | - Shi-Rui Gan
- 2Department of Neurology, First Affiliated Hospital, Fujian Medical University, Fuzhou, China
| | - Zhi-Jun Liu
- 3Department of Neurology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Wang Ni
- 1Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China
| | - Jean-Marc Burgunder
- 4Swiss Huntington's Disease Centre, Siloah, Gümligen and, Department of Neurology, University of Bern, Bern, Switzerland
| | - X William Yang
- 5Center for Neurobehavioral Genetics, Jane and Terry Semel Institute for Neuroscience and Human Behavior, Department of Psychiatry and Biobehavioral Sciences, Brain Research Institute, David Geffen School of Medicine, University of California at Los Angeles, CA, USA
| | - Zhi-Ying Wu
- 1Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, and Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China.,6Joint Institute for Genetics and Genome Medicine between Zhejiang University and University of Toronto, Zhejiang University, Hangzhou, China
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Garcia TP, Marder K, Wang Y. Statistical modeling of Huntington disease onset. HANDBOOK OF CLINICAL NEUROLOGY 2018; 144:47-61. [PMID: 28947125 DOI: 10.1016/b978-0-12-801893-4.00004-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Huntington disease (HD) is caused by a CAG trinucleotide expansion in the huntingtin gene. We now have the power to predict age-at-onset from subject-specific features like motor and neuroimaging measures. In clinical trials, properly modeling onset age is important, because it improves power calculations and directs clinicians to recruit subjects with certain features. The history of modeling onset, from simple linear and logistic regression to advanced survival models, is discussed. We highlight their advantages and disadvantages, emphasizing the methodological challenges when genetic mutation status is unavailable. We also discuss the potential bias and higher variability incurred from the uncertainty associated with subjective definitions for onset. Methods to adjust for the uncertainty in survival models are still in their infancy, but would be beneficial for HD and neurodegenerative diseases with long prodromal periods like Alzheimer's and Parkinson's disease.
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Affiliation(s)
- Tanya P Garcia
- Department of Epidemiology and Biostatistics, Texas A&M Health Science Center, College Station, TX, United States.
| | - Karen Marder
- Departments of Neurology and Psychiatry, Sergievsky Center and Taub Institute, Columbia University Medical Center, New York, NY, United States
| | - Yuanjia Wang
- Department of Biostatistics, Mailman School of Public Health, Columbia University, New York, NY, United States
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6
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Risk factors for the onset and progression of Huntington disease. Neurotoxicology 2017; 61:79-99. [PMID: 28111121 DOI: 10.1016/j.neuro.2017.01.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 01/11/2017] [Indexed: 01/10/2023]
Abstract
Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder characterized by chorea, behavioural and psychiatric manifestations, and dementia, caused by a CAG triplet repeat expansion in the huntingtin gene. Systematic review of the literature was conducted to determine the risk factors for the onset and progression of HD. Multiple databases were searched, using terms specific to Huntington disease and to studies of aetiology, risk, prevention and genetics, limited to studies on human subjects published in English or French between 1950 and 2010. Two reviewers independently screened the abstracts and identified potentially relevant articles for full-text review using predetermined inclusion criteria. Three major categories of risk factors for onset of HD were identified: CAG repeat length in the huntingtin gene, CAG instability, and genetic modifiers. Of these, CAG repeat length in the huntingtin gene is the most important risk factor. For the progression of HD: genetic, demographic, past medical/clinical and environmental risk factors have been studied. Of these factors, genetic factors appear to play the most important role in the progression of HD. Among the potential risk factors, CAG repeat length in the mutant allele was found to be a relatively consistent and significant risk factor for the progression of HD, especially in motor, cognitive, and other neurological symptom deterioration. In addition, there were many consistent results in the literature indicating that a higher number of CAG repeats was associated with shorter survival, faster institutionalization, and earlier percutaneous endoscopic gastrostomy.
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7
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Krench M, Cho RW, Littleton JT. A Drosophila model of Huntington disease-like 2 exhibits nuclear toxicity and distinct pathogenic mechanisms from Huntington disease. Hum Mol Genet 2016; 25:3164-3177. [PMID: 27288455 DOI: 10.1093/hmg/ddw166] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 04/22/2016] [Accepted: 05/20/2016] [Indexed: 12/23/2022] Open
Abstract
Huntington disease-like 2 (HDL2) and Huntington disease (HD) are adult-onset neurodegenerative diseases characterized by movement disorders, psychiatric disturbances and cognitive decline. Brain tissue from HD and HDL2 patients shows degeneration of the striatum and ubiquitinated inclusions immunoreactive for polyglutamine (polyQ) antibodies. Despite these similarities, the diseases result from different genetic mutations. HD is caused by a CAG repeat expansion in the huntingtin (HTT) gene, while HDL2 results from an expansion at the junctophilin 3 (JPH3) locus. Recent evidence indicates that the HDL2 expansion may give rise to a toxic polyQ protein translated from an antisense mRNA derived from the JPH3 locus. To investigate this hypothesis, we generated and characterized a Drosophila HDL2 model and compared it with a previously established HD model. We find that neuronal expression of HDL2-Q15 is not toxic, while the expression of an expanded HDL2-Q138 protein is lethal. HDL2-Q138 forms large nuclear aggregates, with only smaller puncta observed in the cytoplasm. This is in contrast to what is observed in a Drosophila model of HD, where polyQ aggregates localize exclusively to the cytoplasm. Altering localization of HLD2 with the addition of a nuclear localization or nuclear export sequence demonstrates that nuclear accumulation is required for toxicity in the Drosophila HDL2 model. Directing HDL2-Q138 to the nucleus exacerbates toxicity in multiple tissue types, while confining HDL2-Q138 to the cytoplasm restores viability to control levels. We conclude that while HD and HDL2 have similar clinical profiles, distinct pathogenic mechanisms are likely to drive toxicity in Drosophila models of these disorders.
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Affiliation(s)
- Megan Krench
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences
| | - Richard W Cho
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences.,Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - J Troy Littleton
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences .,Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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8
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MacLeod R, Tibben A, Frontali M, Evers-Kiebooms G, Jones A, Martinez-Descales A, Roos RA. Recommendations for the predictive genetic test in Huntington's disease. Clin Genet 2012; 83:221-31. [PMID: 22642570 DOI: 10.1111/j.1399-0004.2012.01900.x] [Citation(s) in RCA: 140] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Revised: 05/08/2012] [Accepted: 05/22/2012] [Indexed: 01/27/2023]
Affiliation(s)
- R MacLeod
- Genetic Medicine, Manchester Academic Health Science Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK.
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9
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Quarrell O, O'Donovan KL, Bandmann O, Strong M. The Prevalence of Juvenile Huntington's Disease: A Review of the Literature and Meta-Analysis. PLOS CURRENTS 2012; 4:e4f8606b742ef3. [PMID: 22953238 PMCID: PMC3426104 DOI: 10.1371/4f8606b742ef3] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Juvenile Huntington's disease (JHD) is usually defined as Huntington's disease with an onset ≤ 20 years. The proportion of JHD cases reported in studies of Huntington's disease (HD) varies. A review of the literature found 62 studies that reported the proportion of JHD cases amongst all HD cases. The proportion of JHD cases in these studies ranged from 1% to 15%, and in a meta-analysis the pooled proportion of JHD cases was 4.92% (95% confidence interval of 4.07% to 5.84%). Limiting the analysis to the 25 studies which used multiple methods of ascertainment resulted in a similar pooled proportion of 5.32%, (95% confidence interval 4.18% to 6.60%). A small difference was observed when the meta-analysis was restricted to studies from countries defined by the World Bank as high income, that used multiple methods of ascertainment, and that were conducted since 1980 (4.81%, 95% confidence interval 3.31% to 6.58%, n=11). This contrasts with the pooled result from three post 1980 studies using multiple methods of ascertainment from South Africa and Venezuela, defined by the World Bank as upper middle income, where the estimated mean proportion was 9.95%, (95% confidence interval 6.37% to 14.22%). These results, which are expected to be more robust than those from a single study alone, may be helpful in estimating the proportion of JHD cases in a given population. Key Words: Juvenile Huntington's disease, prevalence, epidemiology.
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10
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Zhang Y, Long JD, Mills JA, Warner JH, Lu W, Paulsen JS. Indexing disease progression at study entry with individuals at-risk for Huntington disease. Am J Med Genet B Neuropsychiatr Genet 2011; 156B:751-63. [PMID: 21858921 PMCID: PMC3174494 DOI: 10.1002/ajmg.b.31232] [Citation(s) in RCA: 173] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Accepted: 08/02/2011] [Indexed: 11/08/2022]
Abstract
The identification of clinical and biological markers of disease in persons at risk for Huntington disease (HD) has increased in efforts to better quantify and characterize the epoch of prodrome prior to clinical diagnosis. Such efforts are critical in the design and implementation of clinical trials for HD so that interventions can occur at a time most likely to increase neuronal survival and maximize daily functioning. A prime consideration in the examination of prodromal individuals is their proximity to diagnosis. It is necessary to quantify proximity so that individual differences in key marker variables can be properly interpreted. We take a data-driven approach to develop an index that can be viewed as a proxy for time to HD diagnosis known as the CAG-Age Product Scaled or CAP(S) . CAP(S) is an observed utility variable computed for all genetically at-risk individuals based on age at study entry and CAG repeat length. Results of a longitudinal receiver operating characteristic (ROC) analysis showed that CAP(S) had a relatively strong ability to predict individuals who became diagnosed, especially in the first 2 years. Bootstrap validation provided evidence that CAP(S) computed on a new sample from the same population could have similar discriminatory power. Cutoffs for the empirical CAP(S) distribution can be used to create a classification for mutation-positive individuals (Low-Med-High), which is, useful for comparison with the naturally occurring mutation-negative Control group. The classification is an improvement over the one currently in use as it is based on observed data rather than model-based estimated values. © 2011 Wiley-Liss, Inc.
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Affiliation(s)
- Ying Zhang
- Department of Biostatistics, University of Iowa, Iowa City, IA
| | | | - James A. Mills
- Department of Psychiatry, University of Iowa, Iowa City, IA
| | | | - Wenjing Lu
- Department of Biostatistics, University of Iowa, Iowa City, IA
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Reedeker N, Van Der Mast RC, Giltay EJ, Van Duijn E, Roos RA. Hypokinesia in Huntington's disease co-occurs with cognitive and global dysfunctioning. Mov Disord 2010; 25:1612-8. [DOI: 10.1002/mds.23136] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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12
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Langbehn DR, Hayden M, Paulsen JS. CAG-repeat length and the age of onset in Huntington disease (HD): a review and validation study of statistical approaches. Am J Med Genet B Neuropsychiatr Genet 2010; 153B:397-408. [PMID: 19548255 PMCID: PMC3048807 DOI: 10.1002/ajmg.b.30992] [Citation(s) in RCA: 242] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
CAG-repeat length in the gene for HD is inversely correlated with age of onset (AOO). A number of statistical models elucidating the relationship between CAG length and AOO have recently been published. In the present article, we review the published formulae, summarize essential differences in participant sources, statistical methodologies, and predictive results. We argue that unrepresentative sampling and failure to use appropriate survival analysis methodology may have substantially biased much of the literature. We also explain why the survival analysis perspective is necessary if any such model is to undergo prospective validation. We use prospective diagnostic data from the PREDICT-HD longitudinal study of CAG-expanded participants to test conditional predictions derived from two survival models of AOO of HD. A prior model of the relationship of CAG and AOO originally published by Langbehn et al. yields reasonably accurate predictions, while a similar model by Gutierrez and MacDonald substantially overestimates diagnosis risk for all but the highest risk participants in this sample. The Langbehn et al. model appears accurate enough to have substantial utility in various research contexts. We also emphasize remaining caveats, many of which are relevant for any direct application to genetic counseling.
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Affiliation(s)
- Douglas R. Langbehn
- Department of Psychiatry, Carver College of Medicine, and Biostatistics (secondary), University of Iowa, Iowa City, Iowa, USA, Department of Biostatistics (secondary), School of Public Health, University of Iowa, Iowa City, Iowa, USA
| | - Michael Hayden
- Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jane S. Paulsen
- Department of Psychiatry, Carver College of Medicine, and Biostatistics (secondary), University of Iowa, Iowa City, Iowa, USA
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Estimating decreased risks for Huntington disease without a test. Eur J Epidemiol 2008; 23:281-7. [DOI: 10.1007/s10654-008-9224-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2007] [Accepted: 01/08/2008] [Indexed: 11/30/2022]
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Abstract
Worldwide, predictive testing for Huntington's disease has become an accepted clinical application that has allowed many individuals from HD-families to proceed with their life without the uncertainty of being at risk. International guidelines have extensively contributed to establishing counselling programmes of high quality, and have served as a model for other genetic disorders. Psychological follow-up studies have increased the insight into the far-reaching impact of test results for all individuals involved. Although the guidelines have served as a useful frame of reference, clinical experience has shown the importance of a case-by-case approach to do justice to the specific needs of the individual test candidate. Issues such as ambiguous test results, lack of awareness in a test candidate of early signs of the disease, non-compliance to the test protocol, or the test candidate's need for information on the relationship between age at onset and CAG-repeat require careful consideration. Receiving a test result is only one of the transition points in the life of an individual at risk; such result needs to be valued from a life-cycle perspective.
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Affiliation(s)
- Aad Tibben
- Centre for Human and Clinical Genetics, Leiden University Medical Centre, Leiden, The Netherlands.
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Kaptein AA, Helder DI, Scharloo M, Van Kempen GMJ, Weinman J, Van Houwelingen HJC, Roos RAC. Illness perceptions and coping explain well-being in patients with Huntington's disease. Psychol Health 2006. [DOI: 10.1080/14768320500456947] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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16
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Bonke B, Tibben A, Lindhout D, Stijnen T. Calculating risk changes after negative mutation test outcomes for autosomal dominant hereditary late-onset disorders. Heredity (Edinb) 2006; 96:259-61. [PMID: 16391548 DOI: 10.1038/sj.hdy.6800790] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
We demonstrate, in a specific scenario, the effect of negative test results from relatives in families at risk for an autosomal dominant hereditary late-onset disorder. A hypothetical pedigree, of a family at risk of Huntington's disease, was used to demonstrate the consequences for the risk status of various family members in the case where relatives have been tested, and found to be mutation negative. We argue that accurate assessment of conditional probabilities in clinical genetics is important for individuals at risk for hereditary disorders with Mendelian transmission patterns; our formulae offer the opportunity -- when simplifying assumptions are met -- to determine the changed risk status of individuals in such cases.
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Affiliation(s)
- B Bonke
- Department of Medical Psychology and Psychotherapy, Netherlands Institute of Health Sciences, Erasmus MC, PO Box 1738, Rotterdam 3000 DR, The Netherlands.
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Wintrebert CMA, Zwinderman AH, Maat-Kievit A, Roos RA, van Houwelingen HC. Assessing genetic effects in survival data by correlating martingale residuals with an application to age at onset of Huntington disease. Stat Med 2006; 25:3190-200. [PMID: 16416406 DOI: 10.1002/sim.2245] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Genetic models for survival data are hard to formulate and hard to fit. For example, the popular gamma-frailty model for sib-pair data does not generalize easily to extended pedigrees and is not easy to fit. In this paper we show how martingale residuals from a (marginal) Cox model can be employed to estimate the presence of a genetic effect and to estimate genetic correlations depending on the genetic distance (kinship). The methodology is applied to age at onset of Huntington disease (HD) in carriers of the HD gene. The number of CAG repeats in the HD gene is a well-known predictor for age at onset of the disease. However, there is an indication that other genes might be involved as well; leading to unexplained familial clustering. Using our methodology, we found a clearly significant genetic association between the martingale residuals with correlations of about 0.6 for relatives that share 50 per cent of their genes (sib-pairs and parent-child) and about 0.3 for relatives that share 25 per cent of their genes (grandparent-grandchild, uncle/aunt-niece/nephew).
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Affiliation(s)
- Claire M A Wintrebert
- Department of Medical Statistics, Leiden University Medical Centre, P.O. Box 9604, Leiden, 2300 RC, The Netherlands.
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18
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Timman R, Claus H, Slingerland H, van der Schalk M, Demeulenaere S, Roos RAC, Tibben A. Nature and Development of Huntington Disease in a Nursing Home Population. Cogn Behav Neurol 2005; 18:215-22. [PMID: 16340395 DOI: 10.1097/01.wnn.0000191980.62357.d4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
OBJECTIVE The Behavior Observation Scale Huntington (BOSH) was developed to obtain a detailed description of the manifestation of Huntington disease (HD) in the final stages. BACKGROUND The Unified Huntington's Disease Rating Scale (UHDRS), developed to assess Huntington patients' clinical capacities, does not differentiate adequately in later stages of the disease. A scale easy to administer by nursing personnel for progression of the disease in later stages was needed. METHOD Two pilot questionnaires preceded the final version of the BOSH. Observers administered the final version twice independently on 91 patients in 4 nursing homes. RESULTS The BOSH contains 32 items in 3 subscales: 1) activities of daily living (ADL), 2) social-cognitive functioning, and 3) mental rigidity and aggression. Internal and interrater reliabilities were between 0.83 and 0.95. Rigidity and aggression become more frequent as the disease progresses; later on, this behavior diminishes. Social-cognitive capabilities deteriorate more rapidly in later stages. CONCLUSIONS This study sought to develop a scale for assessing behaviors and individual differences in later stages of HD. The findings support the use of the BOSH in identifying these behaviors and differences.
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Affiliation(s)
- Reinier Timman
- Leiden University Medical Center, Department of Neurology, Leiden, The Netherlands.
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Bonke B, Tibben A, Lindhout D, Clarke AJ, Stijnen T. Genetic risk estimation by healthcare professionals. Med J Aust 2005; 182:116-8. [PMID: 15698355 DOI: 10.5694/j.1326-5377.2005.tb06610.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2004] [Accepted: 11/30/2004] [Indexed: 11/17/2022]
Abstract
OBJECTIVES To assess whether healthcare professionals correctly incorporate the relevance of a favourable test outcome in a close relative when determining the level of risk for individuals at risk for Huntington's disease. DESIGN AND SETTING Survey of clinical geneticists and genetic counsellors from 12 centres of clinical genetics (United Kingdom, 6; The Netherlands, 4; Italy, 1; Australia, 1) in May-June 2002. Participants were asked to assess risk of specific individuals in 10 pedigrees, three of which required use of Bayes' theorem. PARTICIPANTS 71 clinical geneticists and 41 other healthcare professionals involved in genetic counselling. MAIN OUTCOME MEASURES Proportion of respondents correctly assessing risk in the three target pedigrees; proportion of respondents who were confident of their estimate. RESULTS 50%-64% of respondents (for the three targets separately) did not include the favourable test information and incorrectly estimated the risks as being about equal to the prior risks; 77%-91% of these respondents were "sure" or "completely sure" that their estimations were correct. Twenty of the 112 respondents correctly estimated the risks for all three target pedigrees. CONCLUSIONS Clinical geneticists and genetic counsellors frequently use prior risks in situations where Bayes' theorem should be applied, leading to overestimations of the risk for an individual.
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Affiliation(s)
- Benno Bonke
- Department of Medical Psychology and Psychotherapy, Erasmus MC, Rotterdam, The Netherlands.
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Langbehn DR, Brinkman RR, Falush D, Paulsen JS, Hayden MR. A new model for prediction of the age of onset and penetrance for Huntington's disease based on CAG length. Clin Genet 2004; 65:267-77. [PMID: 15025718 DOI: 10.1111/j.1399-0004.2004.00241.x] [Citation(s) in RCA: 571] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Huntington's disease (HD) is a neurodegenerative disorder caused by an unstable CAG repeat. For patients at risk, participating in predictive testing and learning of having CAG expansion, a major unanswered question shifts from "Will I get HD?" to "When will it manifest?" Using the largest cohort of HD patients analyzed to date (2913 individuals from 40 centers worldwide), we developed a parametric survival model based on CAG repeat length to predict the probability of neurological disease onset (based on motor neurological symptoms rather than psychiatric onset) at different ages for individual patients. We provide estimated probabilities of onset associated with CAG repeats between 36 and 56 for individuals of any age with narrow confidence intervals. For example, our model predicts a 91% chance that a 40-year-old individual with 42 repeats will have onset by the age of 65, with a 95% confidence interval from 90 to 93%. This model also defines the variability in HD onset that is not attributable to CAG length and provides information concerning CAG-related penetrance rates.
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Affiliation(s)
- D R Langbehn
- Department of Psychiatry, University of Iowa College of Medicine, Iowa City, IA, USA
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Abstract
Neurodegenerative diseases are increasingly common in elderly patients, who present a particular anaesthetic challenge. The majority of people over the age of 70 years have some degree of cerebral atrophy. The pathogenesis of neurodegenerative diseases is due to alterations in the transport, degradation and aggregation of proteins. Alterations in physiology that occur with advancing age affect both the pharmacokinetics and pharmacodynamics of drugs used in the elderly. Changes in pharmacokinetics result in either increased or reduced drug concentrations depending on the variable contributions of absorption, metabolism and elimination. The distribution of a drug depends on its protein binding, cardiac output and blood volume, which are all altered in the elderly. Metabolism and excretion of drugs are also affected due to changes in hepatic and renal mass and blood flow in the elderly. A number of drugs are used in neurodegenerative disorders including antidepressants, benzodiazepines, antipsychotics, acetylcholinesterase inhibitors and levodopa. Polypharmacy is a common problem, which can lead to adverse drug interactions and an exacerbation of dementia. Levodopa, bromocriptine and tricyclic antidepressants are known to cause orthostatic hypotension in patients with neurodegenerative disease. Elderly patients are liable to excessive sedation from benzodiazepines in both the pre- and postoperative period; therefore these drugs should be prescribed in low doses. For induction of general anaesthesia propofol is a suitable agent in patients with neurodegenerative disease due to its rapid metabolism, but may not be suitable in patients with Parkinson's disease as it can induce spontaneous involuntary movements. Volatile inhalational agents should be administered carefully in the elderly, as they are more sensitive to the depressant cerebral and cardiovascular effects. Levodopa should be avoided in conjunction with halothane, which sensitises the heart to catecholamines. Co-administration of monoamine oxidase inhibitors and opioids should be avoided as it can cause agitation, muscular rigidity, sweating and hyperpyrexia. If an anticholinergic agent is required, then glycopyrronium bromide is the drug of choice in this group of patients, as it does not cross the blood brain barrier. Patients should continue to take their usual medications in hospital and do not let the change in routine alter the times at which treatments are administered. This is particularly relevant to the timing of levodopa in Parkinson's disease, as missed treatment can be detrimental. Regional anaesthesia may, however, have significant advantages in patients with Parkinson's disease, who can continue to take oral levodopa preoperatively, during surgery, if required, and early in the postoperative period. Anti-emetic drugs such as phenothiazines, butyrophenones and metoclopramide should be used carefully in the postoperative period in these patients as their antidopaminergic effects may induce or exacerbate parkinsonian effects.
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Affiliation(s)
- Deborah A Burton
- Department of Anaesthesia, St George's Hospital Medical School, London, England.
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Timman R, Maat-Kievit A, Brouwer-DudokdeWit C, Zoeteweij M, Breuning MH, Tibben A. Testing the test--why pursue a better test for Huntington disease? Am J Med Genet B Neuropsychiatr Genet 2003; 117B:79-85. [PMID: 12555240 DOI: 10.1002/ajmg.b.10028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In 1993, the gene mutation for Huntington disease (HD) was identified and testing became possible with a reliability of >99%, without the need for co-operation of relatives. In 1997, a systematic information program offered the mutation retest to individuals who had earlier received a linkage test result for HD, which has a residual uncertainty of 1-9%. The characteristics of 129 individuals tested by linkage analysis for HD are reported on, as well as the reasons for their reassessment by mutation testing. Three groups were compared: (1) people who were retested between 1993 and 1997, before this study had started, (2) people who were retested after we provided information, and (3) persons who refrained from retesting. Nearly half of the linkage-tested individuals were retested, with the exception of noncarriers with a residual risk of 1 or 2%. Of them, less than one out of five were retested. Carriers with a hopeful view on the future (BHS) and a better sense of well-being (GHQ) were more likely to have the retest. Female carriers were also more likely to have the retest before we contacted them. Noncarriers who were retested were more anxious (HADS) than noncarriers who refrained from the retest. Retestees were younger at the time of testing. No risk reversals were revealed by this study.
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Affiliation(s)
- Reinier Timman
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands.
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