Primary Progressive Aphasia (PPA) and Primary Progressive Apraxia of Speech (PPAOS) are relatively rare conditions, but these are diagnoses that SLPs may see from time to time on their caseload. Here you’ll find evidence-based recommendations for treating people with PPA or PPAOS. I share recommendations from a 2023 systematic review, plus I extend the conversation to discuss implications for clinical practice with concrete ideas.
Free DIRECT downloads: The SLP’s guide to PPA and PPAOS (cheat sheet). (Email subscribers get free access to all the resources in the Free Subscription Library.)
Outline:
- What is Primary Progressive Aphasia (PPA)?
- 3 variants of PPA.
- What is Primary Progressive Apraxia of Speech (PPAOS)?
- Overview of Wauters et al. (2023) systematic review.
- Treatment outcomes for PPA.
- Treatment outcomes for PPAOS.
- Recommended interventions for PPA.
- Recommendations for PPAOS treatment.
- Implications for clinical practice (WHO-ICF).
- Learn more.
- Related Eat, Speak, & Think posts.
- References.
What is Primary Progressive Aphasia (PPA)?
Primary Progressive Aphasia (PPA) is a neurodegenerative condition that begins with progressive deterioration of language skills. Motor speech skills may or may not be affected. Other neural domains, such as cognitive, motor, and behavior, are relatively spared in the beginning. (Wauters et al., 2023)
People with PPA eventually experience symptoms of cognitive, motor, and behavioral impairments. (Wauters et al., 2023)
3 variants of PPA
There are currently three variants of PPA: nonfluent/agrammatic variant, semantic variant, and logopenic variant. Our patient may also have a “mixed” PPA, involving characteristics of more than one variant.
The information in this section comes from Wauters and colleagues (2023). Duffy et al. (2015) goes into more detail for the neuroimaging results.
Nonfluent/agrammatic variant (nfvPPA)
- Grammatical errors or effortful/halting speech consistent with apraxia of speech.
- Dysarthria may or may not be present.
- Must have at least 2 of the following:
- Impaired comprehension of syntax.
- Intact single word comprehension.
- Spared object knowledge.
- Neuroimaging: includes left posterior-frontal/insular atrophy.
- Most likely associated with FTLD-tau (frontotemporal lobar degeneration).
- May progress to include impairments of executive function and motor skills.
Semantic variant (svPPA)
- Impaired naming of objects or pictures.
- Deficits in single word comprehension.
- At least 3 of the following:
- Impaired object knowledge.
- Surface dyslexia or dysgraphia (deficits in reading or spelling irregular words).
- Able to repeat.
- Spared grammar.
- Intact motor speech skills.
- Neuroimaging: Anterior temporal atrophy (left hemisphere > right).
- Most likely associated with TDP-43 inclusions.
- May progress to include deficits in sleep, appetite, and recognizing faces. May also experience altered libido, emotional blunting, dis-inhibition, and other behavioral changes.
Logopenic variant (lvPPA)
- Impaired word retrieval.
- Deficits in phrase/sentence repetition.
- At least 3 of the following:
- Speech contains phonological errors.
- Grammar is intact.
- Spared single word comprehension.
- Motor speech skills are intact.
- Neuroimaging: atrophy in left temporoparietal areas.
- Most likely associated with Alzheimer pathology.
- May progress to include episodic memory deficits, limb apraxia, and visuospatial deficits.
What is Primary Progressive Apraxia of Speech (PPAOS)?
According to Wauters et al. (2023), Primary Progressive Apraxia of Speech (PPAOS) is a progressive neurodegenerative condition that affects motor speech praxis, leaving language skills relatively intact. PPAOS can occur without aphasia or dysarthria (Duffy et al., 2015).
PPAOS is a relatively new diagnostic category, proposed as early as 2006. Even as of 2023, PPAOS can be diagnosed as nfvPPA, leading to lack of clarity regarding prevalence and efficacy of treatments. Duffy et al. (2015) discusses the rationale for separating out PPAOS from PPA.
Symptoms of PPAOS are similar to acquired AOS following a stroke (Duffy et al., 2015). According to Wauters et al. (2023), symptoms may include:
- Impaired rate: slow rate, increased pauses between syllables, lengthened sounds.
- Deficits in repetition: distortions, additions, repetitions, and substitution.
- Neuroimaging: Includes involvement of the superior lateral premotor and supplementary motor cortices, as well as certain subcortical areas. (Duffy et al., 2015)
- Most likely associated with progressive supranuclear palsy or coticobasal degeneration (Duffy et al., 2015), with FTLD-tau indicated in well-characterized cases (Wauters et al., 2023).
Overview of Wauters et al. (2023) systematic review
Wauters et al. (2023) published a systematic review of speech therapy interventions for PPA and PPAOS. The paper is open access, and I highly recommend reading it for the full details. If you prefer listening, the first author, Lisa Wauters, discusses the highlights with Sarah Baar (SLP)* on the Speech Scope podcast from Medbridge.
*This is an affiliate link. At no extra cost to you, you can help keep Eat, Speak, & Think sustainable if you subscribe through this link or use the code EatSpeakThink. Learn more about the discount.
Studies and participants
This is a high-level summary. Please see the paper for full details.
- 45 “higher-quality” studies (304 participants) were identified.
- 110 participants had nfvPPA.
- 93 had svPPA.
- 96 had lvPPA.
- 4 had PPAnos.
- 1 had mixed PPA.
16 participants had AOS, but none were identified as having PPAOS.
- 146 males, 155 females, 6 not reported.
- Mean age was 67.1 years.
Summary of treatments in the 45 higher-quality studies
- 37 studies: spoken naming or lexical retrieval.
- 4 studies: semantic knowledge.
- 3 studies for each: syntax/morphology, speech production/fluency, and written naming/spelling.
- 2 studies for each: discourse, functional communication, AAC/multimodal communication.
- 1 study: word comprehension.
Lexical retrieval included:
- Errorless learning.
- Cueing or self-cueing for word retrieval (such as phonological, orthographic, semantic, or autobiographical).
- Generative naming.
- Synonyms and antonyms.
- Conversational practice with a communication partner.
Other treatment approaches included:
- Script training.
- Constraint-induced aphasia therapy.
- Using AAC or an assistive device (ex. smartphone to search for target words for recipe).
- Written naming treatment.
- Training multimodal communcation (ex. writing, gesturing).
- Explicit instruction of morphosyntactic structures.
Treatment outcomes for PPA
There are some promising results here, not just for therapy targets, but also for generalization and maintenance! Please see Wauters et al. (2023) for a detailed discussion of the treatment outcomes, but I’ll share the highlights here. I’m focusing on the 45 higher-quality studies here (the authors also report a post-hoc analysis excluding two studies involving tDCS that did not have a sham condition).
Here are some stats from the 45 higher-quality studies. Not all studies reported on generalization, maintenance, or social validity.
- Every study reported a positive outcome for at least one participant.
- 34 of 43 studies showed positive generalization for at least one participant.
- 34 of 38 studies showed maintenance of treatment gains for at least one participant.
- 17 of 19 studies reported a positive outcome on a social validity measure for at least one participant.
Wauters and colleagues conducted a post-hoc analysis of individual participants. Of the 45 higher-quality studies, 29 studies reported results for 56 participants. Here are some stats:
- 53 of 56 participants improved on the primary outcome measure.
- 33 of 53 participants showed generalization.
- 39 of 46 participants maintained their treatment gains (for varying times).
- 17 of 18 participants reported improvement on a social validity measure.
Treatment outcomes for PPAOS
None of the 45 higher-quality studies included treatment for people diagnosed with PPAOS. Five of the higher-quality studies did include 16 with AOS. Four studies included speech production as a target and reported positive results.
Clearly, more research is needed for PPAOS!
Recommended interventions for PPA
Cicerone et al. (2019) provide guidelines for assessing the research evidence to determine which level a particular intervention can be assigned:
- Practice standard.
- Practice guideline.
- Practice option.
- As there are no randomized controlled trials, no intervention approach can be designated as a practice standard.
- Criteria was met to be considered practice guidelines:
- Lexical retrieval treatment: All subtypes of PPA.
- Script training: nfvPPA.
- Criteria was met to be considered practice options:
- All other interventions included in the higher-quality studies: All subtypes of PPA.
Recommendations for PPAOS treatment
So far, we don’t have strong evidence for guidelines for treating PPAOS. This will likely change as new research emerges. In the meantime, we do have some evidence that behavioral therapy can be effective for treating PPAOS. (Wauters et al., 2023)
Until we have more evidence, rely on the evidence for nondegenerative AOS, clinical experience, expert opinion, and general principles for treating other degenerative motor speech disorders. (Wauters et al., 2023)
Implications for clinical practice (WHO-ICF)
I’m adapting recommendations from Baylor & Darling-White’s (2020) framework and Yorkston et al. (2017). We can assess and treat each area of the WHO-ICF model while focusing on a single communicative participation situation that is important to our patient.
Communicative Participation (Baylor & Darling-White, 2020)
- Find one single, specific situation our patient would like to succeed with communication. All of our therapy activities would revolve around this situation. If they have trouble selecting a specific conversation/situation, we can use:
- Motivational Interviewing.
- Life Interests and Values Cards (Haley et al., 2013).
- Other tools, such as a needs assessment.
- Assess baseline and outcomes with a patient reported outcome measure (PROM)
- If you can’t find a relevant PROM that would capture your intended outcome, create your own – it’s easy!
- Self-anchored rating scale such as Likert scale, visual analog scale.
- Goal attainment scaling (can be objective or subjective).
- If you can’t find a relevant PROM that would capture your intended outcome, create your own – it’s easy!
- Design intervention around this single situation.
- Use relevant words/phrases/sentences in your impairment-based treatments (word finding, scripts, etc).
- Teach and support implementation of strategies to counteract environmental or social barriers.
- Address personal perspectives related to the targeted conversational situation.
Impairment (body structure/function)
- Lexical retrieval treatments are impairment-based treatments (see above for the treatments used by the 45 higher-quality studies in the systematic review).
- Assess and treat as we usually do, except choose stimuli relevant to the communication participation situation our patient wants to improve.
- May be most effective early in the course of the disease.
- Prophylactic treatment to slow the decline. (Wauters et al., 2023)
- Impairment-based restorative treatment to regain lost skills. (Wauters et al., 2023)
Activity
- Facilitate our patient’s ability to use lexical retrieval strategies in functional tasks.
- Script training.
- Using AAC or other supportive technology.
Physical and social factors (environment) (Baylor & Darling-White, 2020)
- Physical environment
- Background noise, projecting voice over distance, speech-based technology, educational materials that are difficult to read or understand.
- Social environment
- Attitudes, support, relationships.
- Formal services and policies.
- Select a barrier that can reasonably be reduced.
- We can teach recommendations or brainstorm with our patient on ideas for what would work for them. We can assist our patient with implementing the strategy and brainstorm next steps.
Personal factors (Yorkston et al., 2017)
- Includes personal identity, life views, coping mechanisms, priorities, and values.
- We can provide education, training, coaching, and guidance on many aspects of self-management and self-efficacy skills related to communication and life participation.
- SLPs are experts at helping people improve the self-efficacy skill of performance mastery, but we can do so much more!
- Self-management skills: problem-solving, decision-making, accessing and using resources, relationships, and taking action.
- Self-efficacy skills: performance mastery, finding peer models, reinterpreting symptoms, and social persuasion.
- Assess with motivational interviewing, PROM, needs assessment, self-anchored rating scales, or collaborative GAS.
- Key to remember: negative emotions and self-limitations do not correlate with degree of impairment.
- Skilled intervention ideas include:
- Teaching our patients how to problem-solve their own participation-level problems.
- Training and coaching our patients in the use of strategies and self-advocacy.
- Teaching our patients about their condition and what to expect.
- Sharing resources about support groups, conversation groups, literature, media by other people who have the condition, or participating in research.
- Assisting patients to access and use resources.
- Teach strategies and assist our patients in preparing for medical treatments.
- Devising action plans that feel doable to our patient.
- Exploring the possibility of re-interpreting symptoms. For example, it is likely that external factors contribute to our patient’s communication difficulties, but many patients may assume that the burden is fully on themselves to change or deal with it.
Learn more
- Sarah Baar interviews Lisa Wauters*, first author on the systematic review on PPA/PPAOS on Medbridge’s Speech Scope podcast.
- Open access systematic review by Wauters et al. (2023).
- How to write participation level goals with Baylor & Darling-White’s (2020) model.
- Learn about self-management and self-efficacy training, based on Yorkson et al. (2017).
*This is an affiliate link. At no extra cost to you, you can help keep Eat, Speak, & Think sustainable if you subscribe through this link or use the code EatSpeakThink. Learn more about the discount.
Related Eat, Speak, & Think posts
- Better AOS outcomes with a focus on participation.
- Improve aphasia outcomes by creating intensive home exercise programs.
- How to help adults regain the ability to write.
- How to do AAC evaluations in the home.
- Message banking tutorial.
References
- Baar, S., & Wauters, L. (2024). Is There Reason to Hope With PPA? [Audio podcast episode]. In Speech Scope. Medbridge. https://www.medbridge.com/course-catalog/details/is-there-reason-to-hope-with-PPA-sarah-baar-lisa-wauters/
- Baylor, C., & Darling-White, M. (2020). Achieving Participation-Focused Intervention Through Shared Decision Making: Proposal of an Age- and Disorder-Generic Framework. American Journal of Speech-Language Pathology, 29(3), 1335–1360. https://doi.org/10.1044/2020_AJSLP-19-00043
- Cicerone, K. D., Goldin, Y., Ganci, K., Rosenbaum, A., Wethe, J. V., Langenbahn, D. M., Malec, J. F., Bergquist, T. F., Kingsley, K., Nagele, D., Trexler, L., Fraas, M., Bogdanova, Y., & Harley, J. P. (2019). Evidence-Based Cognitive Rehabilitation: Systematic Review of the Literature From 2009 Through 2014. Archives of physical medicine and rehabilitation, 100(8), 1515–1533. https://doi.org/10.1016/j.apmr.2019.02.011
- Duffy, J. R., Strand, E. A., Clark, H., Machulda, M., Whitwell, J. L., & Josephs, K. A. (2015). Primary Progressive Apraxia of Speech: Clinical Features and Acoustic and Neurologic Correlates. American Journal of Speech-Language Pathology, 24(2), 88–100. https://doi.org/10.1044/2015_AJSLP-14-0174
- Wauters, L. D., Croot, K., Dial, H. R., Duffy, J. R., Grasso, S. M., Kim, E., Schaffer Mendez, K., Ballard, K. J., Clark, H. M., Kohley, L., Murray, L. L., Rogalski, E. J., Figeys, M., Milman, L., & Henry, M. L. (2023). Behavioral Treatment for Speech and Language in Primary Progressive Aphasia and Primary Progressive Apraxia of Speech: A Systematic Review. Neuropsychology review, 10.1007/s11065-023-09607-1. Advance online publication. https://doi.org/10.1007/s11065-023-09607-1
- Yorkston, K., Baylor, C., & Britton, D. (2017). Incorporating the Principles of Self-Management into Treatment of Dysarthria Associated with Parkinson’s Disease. Seminars in speech and language, 38(3), 210–219. https://doi.org/10.1055/s-0037-1602840
Free DIRECT downloads: The SLP’s guide to PPA and PPAOS (cheat sheet). (Email subscribers get free access to all the resources in the Free Subscription Library.)
Featured image by fizkes on Canva.com.
Lisa earned her M.A. in Speech-Language Pathology from the University of Maryland, College Park and her M.A. in Linguistics from the University of California, San Diego.
She participated in research studies with the National Institute on Deafness and other Communication Disorders (NIDCD) and the University of Maryland in the areas of aphasia, Parkinson’s Disease, epilepsy, and fluency disorders.
Lisa has been working as a medical speech-language pathologist since 2008. She has a strong passion for evidence-based assessment and therapy, having earned five ASHA Awards for Professional Participation in Continuing Education.
She launched EatSpeakThink.com in June 2018 to help other clinicians be more successful working in home health, as well as to provide strategies and resources to people living with problems eating, speaking, or thinking.
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