One-Year Reference Norms of Cognitive Change in Spanish Old Adults: Data from the NEURONORMA Sample.

OBJECTIVE: Serial cognitive assessments are useful for many purposes, such as monitoring cognitive decline or evaluating the result of an intervention. In order to determine if an observed change is reliable and meaningful, longitudinal reference data from non-clinical samples are needed. Since neuropsychological outcomes are affected by language and cultural background, cognitive tests should be adapted, and country-based norms collected. The lack of cross-sectional normative data for Spanish population has been partially remediated, but there is still a need of reliable change norms. This paper aims to give an initial response to this need by providing several reliable change indices (RCI) for 1-year follow-up in a Spanish sample. METHOD: A longitudinal observational study was designed. A total of 122 healthy subjects over age 50 were evaluated twice (M = 369.5, SD= 10.7 days) with the NEURONORMA battery. Scores changes were analyzed, and simple discrepancy scores, standard deviation indices, RCI, and standardized regression-based scores were calculated. RESULTS: Significant improvements were observed in variables related to memory, both verbal and visual, visuospatial function, and the completion time of complex problems. Reference tables for several RCI are provided for their use in clinical settings. CONCLUSIONS: Our results confirm the existence of heterogeneous practice effects after 1 year, and support the recommendation of using reliable change norms to avoid misdiagnosis in repeated assessments. This study provides with initial, preliminary norms of cognitive change for its use in Spanish elders. Further studies on larger samples and different inter-visit intervals are still needed.

Cognitive and neuroimaging profiles in mild cognitive impairment and Alzheimer's disease: data from the Spanish Multicenter Normative Studies (NEURONORMA Project).

The aim of this study was to characterize the neuropsychological and neuroimaging profiles of mild cognitive impairment (MCI) and Alzheimer's disease (AD) patients, and to study the magnitude of the differences by comparing both outcomes with healthy subjects in a cross-sectional manner. Five hundred and thirty-five subjects (356 cognitively normal adults (CONT), 79 MCI, and 100 AD) were assessed with the NEURONORMA neuropsychological battery. Thirty CONT, 23 MCI, and 23 AD subjects from this sample were included in the neuroimaging substudy. Patients' raw cognitive scores were converted to age and education-adjusted scaled ones (range 2-18) using co-normed reference values. Medians were plotted to examine the cognitive profile. MRIs were processed by means of FreeSurfer. Effect size indices (Cohen's d) were calculated in order to compare the standardized differences between patients and healthy subjects. Graphically, the observed cognitive profiles for MCI and AD groups produced near to parallel lines. Verbal and visual memories were the most impaired domains in both groups, followed by executive functions and linguistic/semantic ones. The largest effect size between AD and cognitively normal subjects was found for the FCSRT (d = 4.05, AD versus CONT), which doubled the value obtained by the best MRI measure, the right hippocampus (d = 1.65, AD versus CONT). Our results support the notion of a continuum in cognitive profile between MCI and AD. Neuropsychological outcomes, in particular the FCSRT, are better than neuroimaging ones at detecting differences among subjects.

Spanish multicenter normative studies (NEURONORMA project): normative data and equivalence of four BNT short-form versions.

The application of the Boston Naming Test (BNT) is time-consuming and shortened versions need to be developed for screening purposes. The aims of this study were to develop four equivalent 15-item forms of a Spanish adaptation of the BNT, to test the equivalence of the new versions in a clinical sample, and to provide normative data. The normative sample consisted of 340 subjects. The clinical sample included 172 patients (76 Mild Cognitive Impairment and 96 Alzheimer's disease). An empirical procedure was used to develop the shortened versions. All new versions demonstrated satisfactory internal consistency. Pearson's coefficient analysis showed strong relationships among the four short-form versions as well as between each of them and the 60-item test. The inferential confidence interval method demonstrated the equivalence between the four shortened versions. Age and education affected the score of all short-form versions, but sex was found to be unrelated to the performance. Normative data were calculated for midpoint age groups. This paper proposes four 15-item equivalent versions that could be useful and time-saving tools for screening purposes.

Neuropsychology of Alzheimer's disease.

The expression of neurodegenerative diseases can be categorized into three main symptomatic domains: neurological, cognitive and, neuropsychiatric. This review focuses on the cognitive profile and neuropsychological assessment of Alzheimer's disease (AD). The topography and progression of brain neuropathology determines the cognitive expression of the disease. Thus, in accordance with the initial involvement of the medial temporal lobe, cognitive changes in AD start with specific difficulties in encoding and storage of new information. This particular memory deficit can be optimally detected with memory tests that enhance mnemonic retrieval by means of encoding specificity technique such as the Free and Cued Selective Reminding Test (FCSRT). Along the course of the disease, the neuropathology spreads to association cortices, and other neuropsychological deficits can be detected. A comprehensive neuropsychological examination encompassing several cognitive domains can provide a pattern of altered and preserved functions that is helpful to early detection, differential diagnosis and even prognosis of progression in predementia stages. The use of adapted and standardized instruments is necessary to properly estimate cognitive and functional performance in AD.