123I-MIBG myocardial scintigraphy differentiated probable dementia with Lewy bodies from probable Alzheimer's disease with a sensitivity of 68.9% and a specificity of 89.1% using the automated heart-to-mediastinum ratio.
Cross-Sectional (n=133)
Blinded image readers
Yes
Does 123I-MIBG myocardial scintigraphy improve diagnostic accuracy in differentiating probable dementia with Lewy bodies from probable Alzheimer's disease?
123I-MIBG myocardial scintigraphy demonstrates high diagnostic accuracy for differentiating dementia with Lewy bodies from Alzheimer's disease, particularly in patients with mild dementia.
Effect estimate: Sensitivity 68.9%, Specificity 89.1%
BACKGROUND AND PURPOSE: Dementia with Lewy bodies (DLB) needs to be distinguished from Alzheimer's disease (AD) because of important differences in patient management and outcome. Severe cardiac sympathetic degeneration occurs in DLB, but not in AD, offering a potential system for a biological diagnostic marker. The primary aim of this study was to investigate the diagnostic accuracy, in the ante-mortem differentiation of probable DLB from probable AD, of cardiac imaging with the ligand 123I-meta-iodobenzylguanidine (MIBG) which binds to the noradrenaline reuptake site, in the first multicenter study. METHODS: We performed a multicenter study in which we used 123I-MIBG scans to assess 133 patients with clinical diagnoses of probable (n = 61) or possible (n = 26) DLB or probable AD (n = 46) established by a consensus panel. Three readers, unaware of the clinical diagnosis, classified the images as either normal or abnormal by visual inspection. The heart-to-mediastinum ratios of 123I-MIBG uptake were also calculated using an automated region-of-interest based system. RESULTS: Using the heart-to-mediastinum ratio calculated with the automated system, the sensitivity was 68.9% and the specificity was 89.1% to differentiate probable DLB from probable AD in both early and delayed images. By visual assessment, the sensitivity and specificity were 68.9% and 87.0%, respectively. In a subpopulation of patients with mild dementia (MMSE ≥ 22, n = 47), the sensitivity and specificity were 77.4% and 93.8%, respectively, with the delayed heart-to-mediastinum ratio. CONCLUSIONS: Our first multicenter study confirmed the high correlation between abnormal cardiac sympathetic activity evaluated with 123I-MIBG myocardial scintigraphy and a clinical diagnosis of probable DLB. The diagnostic accuracy is sufficiently high for this technique to be clinically useful in distinguishing DLB from AD, especially in patients with mild dementia.
Yoshita et al. (Fri,) conducted a cross-sectional in Dementia with Lewy Bodies vs Alzheimer's disease (n=133). 123I-MIBG myocardial scintigraphy vs. Clinical diagnosis of probable Alzheimer's disease was evaluated on Diagnostic accuracy (sensitivity and specificity) to differentiate probable DLB from probable AD using the automated heart-to-mediastinum ratio (Sensitivity 68.9%, Specificity 89.1%). 123I-MIBG myocardial scintigraphy differentiated probable dementia with Lewy bodies from probable Alzheimer's disease with a sensitivity of 68.9% and a specificity of 89.1% using the automated heart-to-mediastinum ratio.