Speech and Language Therapy for Aphasia After Stroke
An Updated Systematic Review and Meta-Analyses
Aphasia significantly affects the individual, families, and communities. Timely, effective intervention is vital. Speech and language therapy (SLT) is a complex rehabilitation intervention targeting improvement in language and communication abilities (verbal comprehension, spoken language, reading, writing), activity, and participation. Therapy may vary in intervention regimen, theoretical approach, or delivery model.
Our comprehensive updated review1 synthesized evidence of the effectiveness of SLT for aphasia after stroke found in randomized control trials compared with (1) no therapy and (2) other SLT interventions.
We searched a range of databases, including the Cochrane Stroke Group Trials Register, the Cochrane Central Register of Controlled Trials, Cochrane Library Databases, MEDLINE, EMBASE, CINAHL, AMED (Allied and Complementary Medicine Database), LLBA (Linguistics and Language Behaviour Abstracts), and SpeechBITE (Speech Pathology Database for Best Interventions and Treatment Efficacy) (all from inception to September 2015). We also searched ClinicalTrials.gov, the Stroke Trials Registry, Current Controlled Trials, and WHO ICTRP (World Health Organization International Clinical Trials Registry Platform) (all to September 2015). There were no language restrictions. Two reviewers independently classified trials according to the inclusion and exclusion criteria, assessed trial quality, and extracted data. We sought clarification or unpublished data from trialists when required. Using the TIDieR checklist (Template for Intervention Description and Replication), we systematically extracted complex intervention data.
We included 57 randomized controlled trials (74 randomized comparisons; n=3002 participants) in this review. Some informed >1 comparison. Meta-analysis of 27 randomized comparisons (n=1620) comparing the effects of SLT with no SLT demonstrated benefit for participants’ functional communication (P=0.01; standardized mean difference [SMD] 0.28, 95% confidence interval [CI] 0.06–0.49); auditory comprehension (P=0.59; SMD 0.06, 95% CI −0.15 to 0.26); reading (P=0.03, SMD 0.29, 95% CI 0.03–0.55); expressive language naming (P=0.26; SMD 0.14, 95% CI −0.10 to 0.38); writing (P=0.003; SMD 0.41, 95% CI 0.14–0.67; Figure).
Thirty-eight randomized comparisons (n=1242) directly compared different SLT approaches. Those that received higher intensity SLT had significantly better functional communication (P=0.002; SMD 0.69 95% CI 0.25–1.13) and less severe aphasia (P=0.02, SMD 0.38, 95% CI 0.07–0.69) than those who received lower intensity SLT. Notably, the benefits of higher intensity interventions were confounded by higher dropout rates among those groups (P=0.01, odds ratio 2.35, 95% CI 1.20–4.60). Generally, trials randomized small numbers of participants across a range of characteristics (age, time since stroke, and severity profiles), interventions, and outcomes.
Our review provides evidence of the effectiveness of SLT for people with aphasia after stroke in improved functional communication, reading, writing, and expressive language compared with no SLT. Therapy at high intensity may be beneficial but may not be acceptable to all. Continued improvement in quality of SLT trials and reporting of trial findings (which adhere to CONSORT [Consolidated Standards of Reporting Trial] and TIDieR recommendations) will further contribute to transparency, replication of findings, and subsequent meta-analyses. Designing, conducting, and completion of larger research activities will require close collaboration between people with aphasia, clinicians, and researchers. Future research endeavors should seek to establish the optimum approach, regimen, and delivery of SLT for specific patient groups with aphasia after stroke.
This article is based on a Cochrane Review published in The Cochrane Library 2016, Issue 6 (see http://www.thecochranelibrary.com for information). Cochrane Reviews are regularly updated as new evidence emerges and in response to feedback, and the Cochrane Library should be consulted for the most recent version of the review.
Sources of Funding
Prof Brady and the Nursing, Midwifery, and Allied Health Professions Research Unit are supported by the Chief Scientist Office and Dr Campbell is supported by the Chief Nurses Office, both of the Scottish Government’s Health and Social Care Directorate. The views expressed here are those of the authors and not necessarily those of the funders.
Profs Brady, Enderby, and Dr Kelly are speech and language therapists and members of the Royal College of Speech and Language Therapists. Prof Enderby has been involved in two trials included in this review. She did not contribute to the assessment or interpretation of either of these studies within this review. The other authors report no conflicts.
- Received July 6, 2016.
- Revision received July 28, 2016.
- Accepted August 1, 2016.
- © 2016 American Heart Association, Inc.
- Brady MC,
- Kelly H,
- Godwin J,
- Enderby P