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Lee HM, Mercimek-Andrews S, Horvath G, Marchese D, Poulin RE, Krolick A, Tierney KL, Turna J, Wei J, Hwu WL. A position statement on the post gene-therapy rehabilitation of aromatic I-amino acid decarboxylase deficiency patients. Orphanet J Rare Dis 2024; 19:17. [PMID: 38238766 PMCID: PMC10797739 DOI: 10.1186/s13023-024-03019-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 01/11/2024] [Indexed: 01/22/2024] Open
Abstract
Aromatic L-amino acid decarboxylase (AADC) deficiency is a rare genetic disorder of monoamine neurotransmitter synthesis that presents with a range of symptoms, including motor dysfunction and limited attainment of developmental motor milestones. The approval of eladocagene exuparvovec, a gene therapy for AADC deficiency with demonstrated efficacy for motor improvements, now expands the range of motor outcomes possible for patients with this disorder. However, recommendations and guidelines for therapy following treatment with gene therapy are lacking. To ensure patients can reach their full potential following treatment with gene therapy, it is essential they receive rehabilitation therapies designed specifically with their impairments and goals in mind. Therefore, we highlight specific rehabilitative needs of patients following gene therapy and propose a set of recommendations for the post-treatment period based on collective experiences of therapists, physicians, and caregivers treating and caring for patients with AADC deficiency who have been treated with gene therapy. These recommendations include a focus on periods of intensive therapy, facilitating active movements, training for functional abilities, cognitive and communication training, parent/caregiver empowerment, collaboration between therapists and caregivers to develop in-home programs, and the incorporation of supplemental forms of therapy that patients and their families may find more enjoyable and engaging. Many of these rehabilitative strategies may be employed prior to gene therapy. However, these recommendations will be valuable for therapists, caregivers, and wider treatment teams as they prepare for the post-treatment journey with these patients. Furthermore, the considerations and recommendations presented here may prove beneficial outside the AADC deficiency community as gene therapies and other treatments are developed and approved for other rare diseases.
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Affiliation(s)
- Hui-Min Lee
- Department of Medical Genetics and Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, No. 8, Chung-Shan South Road, Taipei, 100226, Taiwan
- Department of Physical Therapy and Assistive Technology, National Yang Ming Chiao Tung University, Linong St. Beitou Dist, No. 155, Sec. 2, Taipei, 112304, Taiwan
| | - Saadet Mercimek-Andrews
- Department of Medical Genetics, University of Alberta, 8613 114 Street, Edmonton, AB, T6G 2H7, Canada
| | - Gabriella Horvath
- Division of Biochemical Genetics, Department of Pediatrics, University of British Columbia, 4480 Oak Street, Vancouver, BC, V6H 3V4, Canada
| | - Diana Marchese
- Department of Pediatric Rehabilitation, Children's Mercy Hospital, 2401 Gillham Road, Kansas City, MO, 64108, USA
- Department of Pediatrics, University of Missouri-Kansas City, 2411 Holmes Street, Kansas City, MO, 64108, USA
| | - Richard E Poulin
- Thai-Chinese International School, 101/177 Moo 7 Soi Mooban Bangpleenives, Prasertsin Road, Bangplee Yai, Samut Prakan, 10540, Thailand
| | - Alexis Krolick
- PTC Therapeutics Inc, 100 Corporate Ct #2400, South Plainfield, NJ, 07080, USA
| | - Kati-Lyn Tierney
- Texas Children's Hospital, 6621 Fannin Street, Houston, TX, 77030, USA
| | - Jasmine Turna
- PTC Therapeutics Inc, 100 Corporate Ct #2400, South Plainfield, NJ, 07080, USA
| | - Judy Wei
- Ruamrudee International School, 6 Soi Ramkhamhaeng 184, Khwaeng Min Buri, Min Buri, Bangkok, 10510, Thailand
| | - Wuh-Liang Hwu
- Department of Medical Genetics and Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, No. 8, Chung-Shan South Road, Taipei, 100226, Taiwan.
- Center for Precision Medicine, China Medical University Hospital, 2 Yude Road, 404, Taichung City, Taiwan.
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Kumar SB, Girish A, Sutar S, Premanand SA, Garg V, Yadav AK, Shukla R, Murthy TPK, Singh TR. A computational study on structural and functional consequences of nsSNPs in human dopa decarboxylase. J Biomol Struct Dyn 2024:1-15. [PMID: 38193892 DOI: 10.1080/07391102.2023.2301517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 11/04/2023] [Indexed: 01/10/2024]
Abstract
The Dopa Decarboxylase (DDC) gene plays an important role in the synthesis of biogenic amines such as dopamine, serotonin, and histamine. Non-synonymous single nucleotide polymorphisms (nsSNPs) in the DDC gene have been linked with various neurodegenerative disorders. In this study, a comprehensive in silico analysis of nsSNPs in the DDC gene was conducted to assess their potential functional consequences and associations with disease outcomes. Using publicly available databases, a complete list of nsSNPs in the DDC gene was obtained. 29 computational tools and algorithms were used to characterise the effects of these nsSNPs on protein structure, function, and stability. In addition, the population-based association studies were performed to investigate possible associations between specific nsSNPs and arthritis. Our research identified four novel DDC gene nsSNPs that have a major impact on the structure and function of proteins. Through molecular dynamics simulations (MDS), we observed changes in the stability of the DDC protein induced by specific nsSNPs. Furthermore, population-based association studies have revealed potential associations between certain DDC nsSNPs and various neurological disorders, including Parkinson's disease and dementia. The in silico approach used in this study offers insightful information about the functional effects of nsSNPs in the DDC gene. These discoveries provide insight into the cellular processes that underlie cognitive disorders. Furthermore, the detection of disease-associated nsSNPs in the DDC gene may facilitate the development of tailored and targeted therapy approaches.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- S Birendra Kumar
- Department of Biotechnology, Ramaiah Institute of Technology, Bengaluru, India
| | - Aishwarya Girish
- Department of Biotechnology, Ramaiah Institute of Technology, Bengaluru, India
| | - Samruddhi Sutar
- Department of Biotechnology, Ramaiah Institute of Technology, Bengaluru, India
| | | | - Vrinda Garg
- Department of Biotechnology, Ramaiah Institute of Technology, Bengaluru, India
| | - Arvind Kumar Yadav
- Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Solan, India
| | - Rohit Shukla
- Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Solan, India
| | - T P Krishna Murthy
- Department of Biotechnology, Ramaiah Institute of Technology, Bengaluru, India
| | - Tiratha Raj Singh
- Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Solan, India
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Simons CL, Hwu WL, Zhang R, Simons MJHG, Bergkvist M, Bennison C. Long-Term Outcomes of Eladocagene Exuparvovec Compared with Standard of Care in Aromatic L-Amino Acid Decarboxylase (AADC) Deficiency: A Modelling Study. Adv Ther 2023; 40:5399-5414. [PMID: 37803205 PMCID: PMC10611606 DOI: 10.1007/s12325-023-02689-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Accepted: 09/15/2023] [Indexed: 10/08/2023]
Abstract
INTRODUCTION Aromatic L-amino acid decarboxylase (AADC) deficiency is a rare disease with symptoms including movement disorders, developmental delays, and autonomic symptoms starting from birth; further, patients with AADC deficiency are at a high risk of death in the first decade of life. Limited information on the impact of treatment with gene therapy on patients' disease trajectories and survival, quality-of-life, and resource usage benefits are available. METHOD A cohort-based model with a lifetime horizon has been developed, based on motor milestones, to estimate the long-term benefits for patients after treatment with eladocagene exuparvovec compared to best supportive care (BSC). The model takes a National Health Service (NHS) perspective using a UK setting. The model comprises two parts: the developmental phase, in which patients with initially no motor function can progress to other motor milestone states, and a long-term projection phase. Efficacy for eladocagene exuparvovec is derived from clinical trial data with a duration up to 120 months. As the incidence of AADC deficiency is low, data for key model inputs is lacking; therefore estimates of survival by motor milestone were based on proxy diseases. A disease-specific utility study provided quality of life inputs and a burden of illness study informed inputs for disease management. RESULTS The model indicates survival (25.25 undiscounted life years gained) and quality-of-life benefits (20.21 undiscounted quality-adjusted life years [QALYs] gained) for patients treated with eladocagene exuparvovec compared to BSC. Resource usage costs are greater for patients treated with eladocagene exuparvovec, mainly due to the increased life expectancy during which patients accrue additional healthcare resource usage. Scenario analyses indicate robust results. CONCLUSION This study assessed long-term outcomes for patients with AADC deficiency. Patients treated with eladocagene exuparvovec were found to have improved survival and quality of life benefits compared to patients treated with BSC.
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Affiliation(s)
- Claire L Simons
- OPEN Health; Evidence & Access, UK, 20 Old Bailey, London, EC4M 7AN, UK
| | - Wuh-Liang Hwu
- Department of Medical Genetics and Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
| | - Rongrong Zhang
- PTC Therapeutics Sweden AB, Stora Avagen 21, 436 34, Askim, Sweden.
| | - Martijn J H G Simons
- OPEN Health, Evidence & Access, Marten Meesweg 107, 3068 AV, Rotterdam, The Netherlands
| | - Mats Bergkvist
- PTC Therapeutics, Inc., 100 Corporate Court, South Plainfield, NJ, 07080-2449, USA
| | - Craig Bennison
- OPEN Health; Evidence & Access, UK, 20 Old Bailey, London, EC4M 7AN, UK
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Himmelreich N, Montioli R, Garbade SF, Kopesky J, Elsea SH, Carducci C, Voltattorni CB, Blau N. Spectrum of DDC variants causing aromatic l-amino acid decarboxylase (AADC) deficiency and pathogenicity interpretation using ACMG-AMP/ACGS recommendations. Mol Genet Metab 2022; 137:359-381. [PMID: 36427457 DOI: 10.1016/j.ymgme.2022.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 10/25/2022] [Accepted: 11/08/2022] [Indexed: 11/13/2022]
Abstract
Pathogenic variants in dopa decarboxylase (DDC), the gene encoding the aromatic l-amino acid decarboxylase (AADC) enzyme, lead to a severe deficiency of neurotransmitters, resulting in neurological, neuromuscular, and behavioral manifestations clinically characterized by developmental delays, oculogyric crises, dystonia, and severe neurologic dysfunction in infancy. Historically, therapy has been aimed at compensating for neurotransmitter abnormalities, but response to pharmacologic therapy varies, and in most cases, the therapy shows little or no benefit. A novel human DDC gene therapy was recently approved in the European Union that targets the underlying genetic cause of the disorder, providing a new treatment option for patients with AADC deficiency. However, the applicability of human DDC gene therapy depends on the ability of laboratories and clinicians to interpret the results of genetic testing accurately enough to diagnose the patient. An accurate interpretation of genetic variants depends in turn on expert-guided curation of locus-specific databases. The purpose of this research was to identify previously uncharacterized DDC variants that are of pathologic significance in AADC deficiency as well as characterize and curate variants of unknown significance (VUSs) to further advance the diagnostic accuracy of genetic testing for this condition. DDC variants were identified using existing databases and the literature. The pathogenicity of the variants was classified using modified American College of Medical Genetics and Genomics/Association for Molecular Pathology/Association for Clinical Genomic Science (ACMG-AMP/ACGS) criteria. To improve the current variant interpretation recommendations, in silico variant interpretation tools were combined with structural 3D modeling of protein variants and applied comparative analysis to predict the impact of the variant on protein function. A total of 422 variants were identified (http://biopku.org/home/pnddb.asp). Variants were identified on nearly all introns and exons of the DDC gene, as well as the 3' and 5' untranslated regions. The largest percentage of the identified variants (48%) were classified as missense variants. The molecular effects of these missense variants were then predicted, and the pathogenicity of each was classified using a number of variant effect predictors. Using ACMG-AMP/ACGS criteria, 7% of variants were classified as pathogenic, 32% as likely pathogenic, 58% as VUSs of varying subclassifications, 1% as likely benign, and 1% as benign. For 101 out of 108 reported genotypes, at least one allele was classified as pathogenic or likely pathogenic. In silico variant pathogenicity interpretation tools, combined with structural 3D modeling of variant proteins and applied comparative analysis, have improved the current DDC variant interpretation recommendations, particularly of VUSs.
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Affiliation(s)
- Nastassja Himmelreich
- Dietmar-Hopp Metabolic Center and Centre for Pediatrics and Adolescent Medicine, University Children's Hospital, Heidelberg, Germany
| | - Riccardo Montioli
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy.
| | - Sven F Garbade
- Dietmar-Hopp Metabolic Center and Centre for Pediatrics and Adolescent Medicine, University Children's Hospital, Heidelberg, Germany.
| | - Jeffrey Kopesky
- Medical Affairs, PTC Therapeutics, Inc., South Plainfield, NJ, USA.
| | - Sarah H Elsea
- Department of Molecular & Human Genetics, Baylor College of Medicine, Houston, TX, USA.
| | - Carla Carducci
- Department of Experimental Medicine, Sapienza University of Rome, Rome, Italy.
| | - Carla B Voltattorni
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy.
| | - Nenad Blau
- Divisions of Metabolism, University Children's Hospital, Zürich, Switzerland.
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Buesch K, Zhang R, Szczepańska K, Veličković V, Turner L, Despotović M, Đorđević B, Russell A. Burden and severity of disease of aromatic L-amino acid decarboxylase deficiency: a systematic literature review. Curr Med Res Opin 2022; 38:1871-1882. [PMID: 35485958 DOI: 10.1080/03007995.2022.2072090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE The objective was to investigate the severity of aromatic L-amino acid decarboxylase deficiency (AADCd) as reported in the published literature and to collate evidence of the clinical manifestations of AADCd, and the impact of the disease on patients, caregivers, and healthcare systems. METHODS Published articles reporting severity of disease or disease impact were eligible for inclusion in this review. Articles were searched in MEDLINE, EMBASE, Cochrane CENTRAL, TRIP medical, and CRD databases in October 2021. The quality of the included studies was investigated using a modified version of the grading system of the Centre for Evidence-Based Medicine (CEBM). Descriptive data of the literature was extracted and a narrative synthesis of the results across studies was conducted. This review is reported according to the PRISMA reporting guidelines for systematic reviews. RESULTS The search identified 970 unique reports, of which 59 met eligibility criteria to be included in the review. Of these, 48 included reports provided details on the clinical manifestations of AADCd. Two reports explored the disease impact on patients, while four described the impact on caregivers. Five reports assessed the impact on healthcare systems. Individuals with AADCd experience very severe clinical manifestations regardless of motor milestones achieved, and present with a spectrum of other complications. Individuals with AADCd present with very limited function, which, in combination with additional complications, substantially impact the quality-of-life of individuals and their caregivers. The five studies which explore the impact on the healthcare system reported that adequate care of individuals with AADCd requires a vast array of medical services and supportive therapies. CONCLUSIONS Irrespective of the ambulatory status of individuals, AADCd is a debilitating disease that significantly impacts quality-of-life for individuals and caregivers. It impacts the healthcare system due to the need for complex coordinated activities of a multidisciplinary specialist team.
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Affiliation(s)
| | | | | | - Vladica Veličković
- Core Models Ltd, London, United Kingdom
- Institute of Public Health, Medical Decision Making and HTA, UMIT, Hall in Tirol, Austria
| | - Lucy Turner
- Core Models Ltd, London, United Kingdom
- Research in Health Consulting, Ottawa, Canada
| | | | - Branka Đorđević
- Core Models Ltd, London, United Kingdom
- Biochemistry Department, Faculty of Medicine, University of Nis, Nis, Serbia
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Bergkvist M, Stephens C, Schilling T, Wang A, Yu X, Goodwin E, Golden L, Kristensen A, Klein M. Aromatic L-amino acid decarboxylase deficiency: a systematic review. FUTURE NEUROLOGY 2022. [DOI: 10.2217/fnl-2022-0012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Aim: To gain greater knowledge regarding the natural history of aromatic L-amino acid decarboxylase (AADC) deficiency, a genetic disorder that causes severe deficits in motor and cognitive development. Materials & methods: A systematic literature review was performed of all case reports and clinical studies published through December 2019 of patients with AADC deficiency. The data were summarized descriptively. Results: The search identified 94 publications that described 237 unique patients. Mean (standard deviation) age at diagnosis was 3.2 (±5.7) years and 16 deaths were reported. Most patients (57%) received the standard of care therapies, which showed limited efficacy in this patient population. Conclusion: AADC deficiency is a devastating disease and prospectively defined natural history studies are warranted to further understand this disease.
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Affiliation(s)
| | | | | | - Antonia Wang
- PTC Therapeutics, Inc., South Plainfield, NJ 07080, USA
| | - Xiaojin Yu
- PTC Therapeutics, Inc., South Plainfield, NJ 07080, USA
| | | | - Lee Golden
- PTC Therapeutics, Inc., South Plainfield, NJ 07080, USA
| | | | - Matthew Klein
- PTC Therapeutics, Inc., South Plainfield, NJ 07080, USA
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Saberian S, Rowan P, Hammes F, Patel P, Fernandez-Cortes F, Buesch K, Beitia Ortiz de Zarate I. Burden of illness of aromatic L-amino acid decarboxylase deficiency: a survey of physicians in Southern Europe. Curr Med Res Opin 2022; 38:1115-1123. [PMID: 35575170 DOI: 10.1080/03007995.2022.2078097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Aromatic L-amino acid decarboxylase deficiency (AADCd) is an ultra-rare genetic neurometabolic disorder caused by mutations in the DDC gene. OBJECTIVE This retrospective, noninterventional study was designed to describe the burden of AADCd including the associated healthcare resource utilization in Southern Europe. METHODS Eleven clinicians completed a patient case study survey for patients with AADCd currently or previously under their care, followed by an interview with each clinician to assess healthcare resource utilization, patient characteristics, and symptoms. RESULTS Clinicians provided data for 20 patients with AADCd, of whom 60% were male. All patients experienced movement disorders, 90% exhibited developmental delay, 85% reported sleeping problems, and 80% experienced gastrointestinal problems. The symptoms varied with disease severity. Patients with AADCd received care from more than 16 different specialists including both medical and paramedical healthcare professionals. Hospitalizations and visits to accident and emergency departments were also frequent. CONCLUSION In terms of symptoms and healthcare resource utilization, the burden of illness of AADCd is substantial. This study provides insights into several aspects of the disease that are difficult to ascertain from published case reports.
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Acaster S, Williams K, Skrobanski H, Buesch K. Using the EQ-5D to measure caregiver health-related quality of life in rare pediatric disease: a study in aromatic L-amino acid decarboxylase deficiency. FUTURE NEUROLOGY 2022. [DOI: 10.2217/fnl-2022-0004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Aims: To evaluate how well the EQ-5D-5L, a generic preference-based measure of health-related quality of life, captures caregiver burden in a rare pediatric neurotransmitter disease. Materials & methods: Caregivers (n = 14) of individuals with aromatic L-amino acid decarboxylase (AADC) deficiency completed qualitative interviews on their experience as a caregiver, the EQ-5D-5L and a background questionnaire. Qualitative and quantitative data were compared to determine whether there was concordance or discordance in the findings. Results: No caregivers reported problems with mobility and self-care in either the qualitative interviews or on the EQ-5D-5L, and there was general concordance for pain/discomfort and anxiety/depression. However, discordance was found for usual activities, with 79% reporting no problems with this dimension on the EQ-5D-5L, compared with 100% describing substantial limitations during the interviews. Conclusion: The EQ-5D-5L may not be appropriate to evaluate caregiver burden in AADC deficiency, where caregivers' perceptions of “usual activities” differ substantially from the general population.
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Affiliation(s)
- Sarah Acaster
- Acaster Lloyd Consulting Ltd. 8th Floor, Lacon House, 84 Theobalds Road, London, WC1X 8NL, UK
| | - Kate Williams
- Acaster Lloyd Consulting Ltd. 8th Floor, Lacon House, 84 Theobalds Road, London, WC1X 8NL, UK
| | - Hanna Skrobanski
- Acaster Lloyd Consulting Ltd. 8th Floor, Lacon House, 84 Theobalds Road, London, WC1X 8NL, UK
| | - Katharina Buesch
- PTC Therapeutics Switzerland GmbH, Tower 2, Turmstrasse 28, CH-6312 Steinhausen/Zug, Switzerland
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Williams K, Skrobanski H, Buesch K, Acaster S. Symptoms and impacts of aromatic l-amino acid decarboxylase (AADC) deficiency among individuals with different levels of motor function. Orphanet J Rare Dis 2022; 17:128. [PMID: 35313922 PMCID: PMC8935094 DOI: 10.1186/s13023-022-02274-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Accepted: 02/27/2022] [Indexed: 11/20/2022] Open
Abstract
Background Aromatic l-amino acid decarboxylase (AADC) deficiency is a rare neurological disorder associated with a range of symptoms and functional impairments. The aim of this study was to describe the experience of AADC deficiency across five different motor milestone health states. Methods Qualitative interviews were conducted with caregivers of individuals with AADC deficiency in Italy, Spain, Portugal and the United States. An interview guide was developed with input from clinical experts and caregivers, and explored the symptoms and impacts of AADC deficiency. Interviews were conducted by telephone and were recorded and transcribed. Data were analysed using thematic analysis and the symptoms and impacts were compared across health states.
Results Fourteen caregivers took part, who provided care to 13 individuals with AADC deficiency aged 1–15 years. Six individuals were in the ‘no motor function’ health state, one in the ‘sitting unsupported’ health state, one in the ‘standing/stepping when fully supported’ health state and five in the ‘walking with minimal support’ health state. The results highlight a substantial impact of AADC deficiency, even among those who were able to walk with minimal support. Overall, those with better motor function also had better functional hand use, communication skills, ability to eat and perform other activities independently, and interact with their peers. The burden of caring was high across all health states, but caregivers of individuals in the walking health state were better able to participate in social and leisure activities. Conclusion Individuals with higher levels of motor function had less severe symptoms and were better able to perform their daily, leisure and social activities. Treatments which improve motor function have the potential to improve other aspects of the lives of individuals with AADC deficiency and their caregivers.
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Skrobanski H, Williams K, Werner C, O'Neill S, Buesch K, Acaster S. The impact of caring for an individual with aromatic l-amino acid decarboxylase (AADC) deficiency: a qualitative study and the development of a conceptual model. Curr Med Res Opin 2021; 37:1821-1828. [PMID: 34259573 DOI: 10.1080/03007995.2021.1955668] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
BACKGROUND Aromatic l-amino acid decarboxylase (AADC) deficiency is a rare neurological condition, associated with a wide range of symptoms and functional issues, such as profound motor impairment and learning disability. Most individuals with AADC deficiency are completely dependent on their caregivers. This study explored the impact of caring for an individual with AADC deficiency. METHODS Qualitative interviews were conducted with caregivers of individuals with AADC deficiency in Italy, Portugal, Spain and the United States. An interview guide was developed with input from clinical experts and caregivers and included questions on the impact of caring for an individual with AADC deficiency. Interviews were conducted by telephone/videoconference and were recorded and transcribed. Data were analysed using thematic analysis. RESULTS Fourteen caregivers took part who provided care to 13 individuals with AADC deficiency aged 1-15 years. Caregivers reported that their lives centred around the individual with AADC deficiency, due to their need for 24-hour care and regular healthcare appointments. They reported both proximal impacts (impact on time, planning, physical health and emotional wellbeing), and distal impacts (impact on social/leisure activities, relationships, work and finances). These concepts and relationships were illustrated in a conceptual model. CONCLUSIONS This is the first qualitative study to report on the experience of caring for an individual with AADC deficiency. Caregivers reported that caring had a substantial multifaceted impact on their lives. These findings highlight the importance of considering the caregiver experience when evaluating the burden of AADC deficiency.
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Affiliation(s)
- Hanna Skrobanski
- Patient-Centred Outcomes Research, Acaster Lloyd Consulting Ltd, London, United Kingdom
| | - Kate Williams
- Patient-Centred Outcomes Research, Acaster Lloyd Consulting Ltd, London, United Kingdom
| | - Christian Werner
- Global Medical Affairs, PTC Therapeutics Germany GmbH, Frankfurt am Main, Germany
| | - Sian O'Neill
- Patient Engagement EMEA, PTC Therapeutics International Limited, Ireland
| | - Katharina Buesch
- Global Health Economics and Outcomes Research, PTC Therapeutics Switzerland GmbH, Steinhausen/Zug, Switzerland
| | - Sarah Acaster
- Patient-Centred Outcomes Research, Acaster Lloyd Consulting Ltd, London, United Kingdom
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