The impact of the CERAD-NP on diagnosis of cognitive deficiencies in late onset depression and Alzheimer's disease.

OBJECTIVES

To identify the most appropriate test combination for distinguishing between late onset depression (LOD) and Alzheimer's disease (AD). To achieve this objective, the Consortium to Establish a Register for Alzheimer's Disease-Neuropsychological Battery (CERAD-NP) data of patients diagnosed with these two conditions were analyzed using multiple regression analysis.

METHODS

In the first regression analysis, the following CERAD-NP subtests were included: verbal fluency, Boston naming test, word list learning, constructional praxis, word list recall, and constructional praxis recall. In a second regression analysis, only CERAD-NP memory parameters were included: word list learning, word list recall, word list intrusions, word list savings, word list recognition, word list false positive errors, constructional praxis recall, and constructional praxis savings.

RESULTS

The combination of word list recall and constructional praxis recall best distinguished between LOD and AD, with a ROC of 0.91. In the stepwise regression of memory measures, word list recall, word list savings, and constructional praxis recall was the best combination, resulting in a ROC of 0.92.

CONCLUSION

The most efficacious combination of the CERAD-NP battery for discriminating between LOD and AD consisted of word list recall and constructional praxis recall. Of the CERAD-NP memory measures, word list recall, word list savings, and constructional praxis recall represented the best diagnostic combination.