Enhancing the effectiveness of cognitive tests for diagnosing dementia

Cognitive difficulties are a symptom of many neurodegenerative conditions, and the benefits of early and accurate diagnosis are well recognized. It gives patients a better chance to participate actively in planning their care and making legal and financial decisions, while helping them and their families to adjust. At the societal level, appropriate early intervention can reduce health-care costs by delaying care home admission.

However, existing methods are not always reliable in detecting the earliest stages of decline as they typically only take account of test scores, with people scoring above a certain level considered healthy. But well-educated people may score highly and look healthy when they are not, while the less well-educated may perform poorly despite being healthy.

Both scenarios highlight the need to make testing more accurate, particularly as effective new drugs for various neurodegenerative diseases are expected to become available in the near future.

To improve the diagnostic tools, researchers within the EU-funded E-SPACE project, run by Dublin City University, Ireland, reviewed existing cognitive-screening literature. Based on the reviews, they identified two widely used sets of tests that could benefit most from modification using an approach that takes into account aspects other than test scores.

Work with healthy older volunteers helped to determine participants’ responses and behavior during the testing. Based on these findings, changes were made to increase the amount of information that could be collected in a single session. Testing of both healthy and cognitively impaired older adults with the modified versions was then expanded in Ireland, Spain and the United States.

The modified tests are administered in the usual manner, but clinicians now register answers verbatim and examine them in detail. They are being used in two specialist memory clinics in Ireland, with further sites expected to take them up, and have been piloted in the USA. Work on a Spanish version of the tests is ongoing, while the development of a computerized format is also under way.