Logopenic variant Primary Progressive Aphasia
Primary progressive aphasia (PPA) is a language disorder that involves changes in the ability to speak, read, write and understand what others are saying. It is associated with a disease process that causes atrophy in the frontal and temporal areas of the brain, and is distinct from aphasia resulting from a stroke. In 2011, criteria were adopted for the classification of PPA into three clinical subtypes: nonfluent/agrammatic variant PPA, semantic variant PPA and logopenic variant PPA (Gorno-Tempini, Hillis, Weintraub, et. al).
The presenting feature in people with logopenic PPA is deterioration in their ability to retrieve words. These patients present with a slow rate of speech with frequent pauses due to significant word-finding problems. Current research suggests that the fundamental loss in logopenic PPA is in phonologic short-term memory, which also contributes to difficulty with sentence and phrase repetition, and understanding long or complex sentences.
Unlike other FTD subtypes, logopenic PPA generally does not produce changes in behavior or personality until later stages of the disease. Most people with progressive aphasia maintain the ability to care for themselves, keep up outside interests and, in some instances, remain employed for a few years after onset of the disorder.
Key Clinical Features
- The aphasia in logopenic PPA is experienced as problems with word retrieval or word-finding. Despite this difficulty, it appears that patients retain the underlying meaning of words.
- A slow rate of speech with frequent pauses due to difficulty finding the right words; the mechanics or motor skills needed to produce speech are not affected.
- Sentence and phrase repetition is impaired, but repetition of short single words remain spared.
- Reading and writing abilities may be preserved longer than speech, but these eventually decline, as well.
- Over time, people may have trouble understanding long or complex verbal information, due to problems with working memory (auditory attention span).
- Mutism eventually develops with progression.
- Difficulty swallowing may develop late in the course of illness.
Neuroimaging studies demonstrate loss of brain volume, blood flow or neural activity in the left temporal and parietal lobes.
Key Pathologic Features
Recent research indicates that logopenic PPA may be caused most commonly by Alzheimer pathology.
Logopenic PPA can be sporadic, familial or hereditary. The majority of cases are not hereditary.
As with all forms of FTD, there is no cure for PPA, and in most cases its progression cannot be slowed.
Management and Prognosis
Although no studies have shown improvement or slowing of progression when a patient works with a speech and language pathologist (SLP), many centers work with SLPs to hone the diagnosis and to research potential therapeutic interventions.
Patients who do not develop additional behavioral and motor symptoms are able to preserve their independence and active lifestyle for a longer period of time.
Reference: Gorno-Tempini, M.L., Hillis, A.E., Weintraub, S, et.al. Classification of primary progressive aphasia and its variants. Neurology; March, 2011.
For additional information and support:
The International PPA Connection Resources and support for PPA patients and family members
Central location for PPA research