Cognitive rehab shows promise for stroke patients

Medical Tribune September 2009 SFI
David Brill

A cognitive rehabilitation program used after traumatic brain injuries could also help stroke patients to overcome lingering attention deficits, a new study shows.

Stroke survivors who received Attention Process Training (APT) within 4 weeks were better able to concentrate on visual and auditory tasks 6 months later, New Zealand researchers reported in the journal Stroke.

It is the first study to test APT in an important but neglected area of stroke rehabilitation, the researchers say. Concentration problems are very common in stroke patients – affecting quality of life and contributing to poor functional outcomes – yet specific interventions remain largely unstudied.

Singapore stroke expert Dr. Nagaendran Kandiah, a consultant neurologist at the National Neuroscience Institute (NNI), said that APT could be a useful tool for local patients but that equivalent programs would need to be tailored to the language and culture. Researchers at the NNI are already “actively working on this”, he said.

Further research is also needed to better establish the local prevalence of post-stroke attention deficits, he added. Preliminary data from NNI suggest that about 15 to 20 percent of patients have cognitive difficulties, including poor attention, following a stroke.

“There is a significant amount of literature that shows that cognitive training is useful for post-stroke patients. The awareness that attention deficits and other cognitive deficits are common and can be potentially treated needs to be emphasized both to the public and medical community,” said Nagaendran.

The Stroke study researchers randomized 78 stroke patients to receive standard care alone or standard care plus up to 30 hours of APT (mean 13.5 hours). [2009 Jul 23; Epub ahead of print]

APT patients scored significantly better on the Integrated Visual Auditory Continuous Performance Test (IVA-CPT) Full-Scale Attention Quotient (FSAQ), at 5 weeks and 6 months after randomization. The test measures reaction times to auditory and visual stimuli, and can distinguish between genuine attention to the task and impulsive responding.

There were however no significant differences between the groups in other cognitive performance indicators, or broader outcome measures such as the Physical Component Score.

Lead author Dr. Suzanne Barker-Collo, a clinical psychologist and senior lecturer at the University of Auckland, said that she was disappointed that the intervention did not show benefit across other domains but was pleasantly surprised at the magnitude of effect on the primary outcome.

“We were expecting maybe half a standard deviation difference between the groups, and the effect we found was about four times that,” she said.

There are several cognitive rehabilitation packages available but very little evidence on how best to use them in stroke patients, added Barker-Collo, whose ongoing research seeks to better delineate the profile and time course of cognitive deficits after stroke. She is also reviewing the data from the present study to identify factors that could predict which patients will respond best to APT.

“I think cognition after stroke in general has been ignored to some degree,” she said. “A lot of rehabilitation time is spent on more physical tasks like walking, bathing and dressing – it’s very practical but very often the time spent on that means that not as much time is spent on other things like attention and memory, which are a bit less obvious but can still impact on other functional outcomes. Attention deficit in particular is a very, very common problem.”