Age transformation of combined hippocampus and amygdala volume improves diagnostic accuracy in Alzheimer's disease

Hampel, Harald; Teipel, Stefan J; Bayer, Wolfram; Alexander, Gene E; Schwarz, Robert; Schapiro, Mark B; Rapoport, Stanley I; Möller, Hans-Jürgen

« Previous Next »Journal of the Neurological Sciences
Volume 194, Issue 1 , Pages 15-19, 15 February 2002

Age transformation of combined hippocampus and amygdala volume improves diagnostic accuracy in Alzheimer's disease

Harald Hampel
- Corresponding author. Tel.: +49-89-5160-5860; fax: +49-89-5160-5856
- Dementia Research and Neuroimaging Section, Memory Clinic, Department of Psychiatry, Ludwig-Maximilian University, Nussbaumstr.7, 80336 Munich, Germany
Stefan J Teipel
- Dementia Research and Neuroimaging Section, Memory Clinic, Department of Psychiatry, Ludwig-Maximilian University, Nussbaumstr.7, 80336 Munich, Germany
Wolfram Bayer
- Dementia Research and Neuroimaging Section, Memory Clinic, Department of Psychiatry, Ludwig-Maximilian University, Nussbaumstr.7, 80336 Munich, Germany
Gene E Alexander
- Arizona Alzheimer's Research Center and Department of Psychology, Arizona State University, Tempe, AZ, USA
Robert Schwarz
- Dementia Research and Neuroimaging Section, Memory Clinic, Department of Psychiatry, Ludwig-Maximilian University, Nussbaumstr.7, 80336 Munich, Germany
Mark B Schapiro
- Department of Pediatric Neurology, Children Hospital Medical Center, Cincinatti, OH, USA
Stanley I Rapoport
- Brain Physiology and Metabolism Section, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
Hans-Jürgen Möller
- Dementia Research and Neuroimaging Section, Memory Clinic, Department of Psychiatry, Ludwig-Maximilian University, Nussbaumstr.7, 80336 Munich, Germany

Received 26 June 2001; received in revised form 20 September 2001; accepted 5 November 2001.

Abstract

Objective: The specificity of magnetic resonance imaging (MRI)-based hippocampal measurements in detecting Alzheimer's disease (AD) pathology is reduced by an age-related reduction of the hippocampus volume. We propose an adjustment for this age effect to increase the diagnostic accuracy of hippocampal volumes in AD. Method: Using an orthogonal rotational transformation of the coordinate system, values of MRI-determined volumes of hippocampus–amygdala formation (HAF) were transformed according to the age effect in 27 AD patients and 28 age- and sex-matched healthy control subjects. Results: The age transformation increased the diagnostic accuracy of HAF volumes in the study sample and in an independent sample from the literature. The age-transformed HAF volume predicted AD in a subject with mild cognitive impairment (MCI) with later biopsy-confirmed AD. Conclusion: Age transformation may provide an easily applicable method to increase the clinical diagnostic accuracy of hippocampal measurements by considering the effect of aging on hippocampus volume.

Keywords: Alzheimer's disease, Diagnosis, Hippocampus, Magnetic resonance imaging, Discriminant analysis, ROC analysis, Age-transformation

Abbreviations: HAF, hippocampus–amygdala formation, AD, Alzheimer's disease, MRI, magnetic resonance imaging, MMSE, Mini-Mental State Examination, ROC, receiver-operating characteristic