Aphasia – Treatment
effectiveness and evidence
based practice
Treatment Efficacy
• Efficacy: improvements in an individuals
communication as a result of clinical
interventions provided by an SLT
• Difficult to combine results of studies due to
differing:
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Aetiologies
Methodologies
Types and severity of aphasia
Nature of treatment
Enderby and Emerson 1995
Systematic Reviews
• A scientific tool that can be used to
appraise, summarise, and communicate
the results and implications of otherwise
unmanageable quantities of research
• Brings together separately conducted
studies and synthesise their results
• E.g. Cochrane Database
Meta-analysis
• A specific statistical strategy for
assembling the results of several studies
into a single estimate
• Systematic reviews may or may not
include meta-analysis, depending on
whether the studies are similar enough so
that combining their results is meaningful
• Strictly speaking a meta-analysis is an
optional component of a systematic
review. Not inter-changable words!
Cochrane Systematic Reviews
• Kelly, Brady and Enderby (2010)
• 30 RCT’s (involving 1840 participants)
comparing:
– SLT v’s no SLT
– SLT versus social support or stimulation
– One SLT intervention v’s another intervention
• In general, trials randomised small numbers
across a range of characteristics (age, time
since stroke, and severity), interventions and
outcomes
Kelly, Brady and Enderby (2010)
• Concluded some indication for the effectiveness
of SLT for those with aphasia following stroke
(as compared with Enderby 2006b).
• Intense SLT was favoured over conventional
SLT
• Therapist-trained and supervised volunteers as
effective as provision by a professional
• Insufficient evidence for effectiveness of specific
treatment approaches
Systematic Reviews
• Greener, Enderby and Whurr (2006b)
– RCT’s for behavioural treatments for Aphasia
by SLT’s
– 12 studies met criteria
– All had limitations in methodology, and
incompleteness in which operational
definitions and outcomes were
communicated.
– Concluded RCT’s had neither demonstrated
efficacy nor lack of efficacy
Cochrane Review
• Greener, Enderby and Whurr (2010)
– Assessed the effects of drugs on language abilities
for people with aphasia
– Particularly examined Piracetam – drug which
improves memory, cognition, attention, concentration,
motivation
– Has reportedly shown improvements in post stroke
aphasia in some studies
– 10 trials included
– Weak evidence that patients were more likely to have
improved on language measures at the end of the
trial with piracetam
Meta-analysis
• Greenhouse et al (1990)
– Analysed 13 pre-post tests of aphasia treatment
– Average weighted effect size of 0.8 (medium to large
effect of change) from pre-treatment to post treatment
• Whurr Lorch and Nye (1992)
– 45 aphasia treatment studies
– Average effect size 0.59 between treated and
untreated populations.
– Concluded treatments were generally effective
Meta-Analysis
• Robey (1998)
– Analysis of 55 articles – aphasia therapy brought
about positive clinical outcomes
– Positive outcomes were 1.83 times more likely for
those treated in acute period than for untreated
individuals. Advocating early intervention
– Treatment length in excess of 2 hours per week
brought about gains exceeding those of shorter
treatment duration
– Those with severe aphasia also made large gains
• These findings confirmed findings from earlier
study: Robey (1994)
Meta-Analysis
• Holland et al (1996)
– Examined improvements in individual’s
communication behaviour resulting from clinical
interventions from SLT and exceeding what could be
expected from spontaneous recovery alone.
– 9 group studies, all enrolling >60 patients
– Single, left hemi stroke, receiving >3hrs/week therapy
for >5m regardless of time post onset, made
significantly more improvement than people with
aphasia who were not treated
– 13 small group/single subject studies past period of
spontaneous recovery. Gains made in most studies
contributing to efficacy of chronic aphasia
Treatment of Word Retrieval
Deficits in Aphasia
• Summary:
• Task specific semantic therapy improves
semantic activities
• Task specific phonological therapy improves
phonological activities
• Limited evidence that semantic and phonological
cueing improve naming accuracy and word
retrieval abilities
Salter,Teasell, Bhogal, Zettler, Foley (2009)
Evidenced Based Review of Stroke Rehabilitation
Doesborg et al 2004
• RCT of 55 stroke patients 3-5m post onset
• Combined semantic and phonological deficits
• Randomly assigned to:
– Semantic treatment focused on interpretation of
written words, sentences and text (e.g. semantic
categories, anomalous sentences, semantic
definitions)
– Control group focused on word sound structure (e.g.
rhyming, word length, stress patterns, syllabification)
Doesborg et al 2004
• Treatment lasted until 10-12m post onset,
receiving 40-60 hours individual treatment
• After semantic treatment patients significantly
improved on Semantic Association Test.
• After sound structure treatment patients
significantly improved on phonological measures
• All patients improved on Everyday Language
Test
• Improved verbal communication was achieved
for both groups
Treatment for Word Finding in
Aphasia – Nickels (2010)
1. Therapy has item specific effects only
2. Semantic and phonologically focused
treatments are mostly successful in improving
word retrieval.
3. Semantic tasks don’t have to be hard to be
effective
4. Semantic tasks are more effective with those
with less semantic impairment
5. Semantic tasks usually require the word form
to be effective
Treatment of Global Aphasia
• Summary:
• Patients with global aphasia experience less
complete or slower rates of recovery
• Can still benefit from an SLT rehab programme
• Moderate evidence based on small RCT that
intensive “ecological” language therapy is
associated with improvement across modalities
Salter,Teasell, Bhogal, Zettler, Foley (2009)
Evidence Based Review of Stroke Rehab
Denes et al 1996
• RCT of 17 patients with global aphasia
• Random allocation to standard (60 sessions
over 6m) or intensive therapy (130 over 6m)
• Approach in both groups “ecological” –
restoration of language in conversation
• Comprehension targeted > production
• Sessions 45-60min
• Assessed at baseline and 6m Aachen Aphasia
Test
Denes et al 1996
• Results:
– Both groups demonstrated improvement
across all subtests.
– Between group differences significant for
written language subtest only
Aphasia Treatment in Polyglots
• Miertsch, Meisel and Isel (2009)
– Does treatment of 1 language lead to improvement in
all languages?
– 56yr old male, speaking German (L1), English (L2)
and French (L3)
– Left CVA with a medium Wernicke’s aphasia: severe
WFD, semantic paraphasias, paragrammatism.
Auditory language processing and phonological
working memory worse than visual language
processing
– Therapy for the study 8yrs post onset. 2x 45min/day
for 3.5weeks in French.
Therapy
• Bilingual Aphasia Test administered
• 5 exercise types in same order every day.
• Therapy focussed on:
– Oral and auditory word finding of verbs and
nouns
– Exercises with prepositions
– Semantic-conceptual relationships between
words
– Word finding in discourse
Results
• Before training best performance German.
• Post treatment, performance improved
significantly in French as well as English.
German did not improve.
• Further evidence that chronic aphasia can
improve
• 2 Languages share a common semanticconceptual memory system, though would
expect improvement in German too. ?Length of
training too short ?due to capabilities in that
language prior to training.
Conclusions
Generally accepted that SLT works!
Basso (2005), Albert (2003), Bhogal, Teasell and Speechley (2003)
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Aphasia – Treatment effectiveness and evidence based …