Primary Progressive Aphasia: a Core Outcome Set for improving intervention research

INTRODUCTION
Interventions to treat speech-language difficulties in primary progressive aphasia (PPA) often use word accuracy as a highly comparable outcome. However, there are more constructs of importance to people with PPA that have received less attention.

METHODS
Following Core Outcome Set Standards for Development Recommendations (COSSTAD), this study comprised: Stage 1 – systematic review to identify measures; Stage 2 – consensus groups to identify important outcome constructs for people with PPA (n = 82) and care partners (n = 91); Stage 3 – e-Delphi consensus with 57 researchers.

RESULTS
The systematic review identified 84 Outcome Measurement Instruments. Core outcome constructs identified included: (1) Participate in conversations with family and friends, (2) get words out, (3) be more fluent, (4) convey a message by any means, and (5) understand what others are saying. Researchers were unable to reach a consensus on measurement instruments.

DISCUSSION
Further work is required to develop appropriate measurement instruments that address all core outcome constructs important to key stakeholders.

Highlights
We introduce new symptom-led perspectives on primary progressive aphasia (PPA).
The focus is on non-fluent/agrammatic (nfvPPA) and semantic (svPPA) variants.
Foregrounding of early and non-verbal features of PPA and clinical trajectories is featured.
We introduce a symptom-led staging scheme for PPA.
We propose a prototype for a functional impairment scale, the PPA Progression Planning Aid.

Aim

There is currently no curative treatment for Primary Progressive Aphasia (PPA), a language led dementia that progresses inexorably over time. Symptomatic pharmacological therapies have also not shown any evidence of effectiveness. Speech and language therapists and neuroscientists across the world have, however, worked for many years on tailored programmes for such people with PPA, and multiple interventions have emerged. Yet, research examining the effectiveness of these lack rigour, with small sample sizes and a lack of consistency in outcome measures posing limitations to the generalisability of the work. In this international cross-disciplinary collaboration we propose the development of a core set of outcome measures for researchers in the field of PPA interventions. This is extremely important in allowing this field of intervention research to develop, improving the rigour and impact of the work being undertaken. This will provide benefits for individuals with PPA worldwide, increasing access to interventions that can maintain communication, relationships and independence.

Contributors

Anna Volkmer, Emily Viega Alves, Hagit Bar-Zeev, Elena Barbieri, Petronilla Battista, Ashleigh Beales, Barbara Costa Beber, Emilie Brotherhood, Ines Ribeiro Cadorio, Maria Teresa Carthery-Goulart, Jade Cartwright, Sebastian Crutch, Karen Croot, Maria Isabel d´Ávila Freitas, Jeanne Gallée, Stephanie M. Grasso, Katarina Haley, Heleen Hendriksen, Shalom Henderson, Lize Jiskoot, Isabel Junqueira Almeida, Jackie Kindell, Rachel Kingma, Lorinda LY Kwan-Chen, Monica Lavoie, Adi Lifshitz-Ben-Basat, Regina Jokel, Aurore Mahut-Dubos, Jordi A. Matias-Guiu, Michèle Masson-Trottier, Marcus Meinzer, Ellen McGowan, Carolina Mendez-Orellana, Aaron M. Meyer, Carly Millanski, Núria Montagut, Aimee Mooney, Darby J. Morhardt, Lyndsey Nickels, Monica Norvik, Iris Edda Nowenstein, Avanthi Paplikar, Margaret Pozzebon, Antoine Renard, Leanne Ruggero, Emily Rogalski, Anna U. Rysop, Fredrik Sand Aronsson, Aida Suárez-González, Sharon Savage, Mai Tran Thi, Kyriana Tsapkini, Cathleen Taylor-Rubin, Donna C. Tippett, Nina Unger, Lizet van Ewijk, Sandra Wielaert, Ingvild Elisabeth Winsnes, Anne Whitworth, Ibrahim Can Yasa, David Copland, Maya L. Henry, Jason D. Warren, Rosemary Varley, Sarah J. Wallace, Chris J. D. Hardy

Publication

Journal: Alzheimer's & Dementia
Volume:
Issue:
Pages: -
Year: 2024
DOI: https://doi.org/10.1002/alz.14362

Further Study Information

Current Stage: Completed
Date: March 2021
Funding source(s): UCL Grand Challenge


Health Area

Disease Category: Neurology, Rehabilitation

Disease Name: Primary Progressive Aphasia (PPA)

Target Population

Age Range: 18 - 120

Sex: Either

Nature of Intervention: Rehabilitation

Stakeholders Involved

- Clinical experts
- Consumers (caregivers)
- Consumers (patients)
- Families
- Researchers

Study Type

- COS for clinical trials or clinical research

Method(s)

- Consensus conference
- Consensus meeting
- Focus group(s)
- Interview
- Nominal group technique (NGT)
- Semi structured discussion
- Systematic review

In this international cross-disciplinary collaboration we propose the development of a core set of outcome measures for researchers in the field of PPA interventions. We propose this comprise a series of stages including:

Stage 1: Systematic review of outcome measures currently described in the intervention research literature for people with PPA.
Stage 2: Identification of the most important outcomes through international consultation with key stakeholders including people with PPA and their families, clinical speech and language therapists, neurologist and neuro-psychologists amongst other health professional groups. To be conducted remotely.
Stage 3: Consensus work with an international group of researchers in the field, to identify the key constructs and core outcomes for each of these. To be conducted remotely at forthcoming working party meetings.