Slaets Sylvie, Van Acker Frank, Versijpt Jan, Hauth Lothar, Goeman Johan, Martin Jean-Jacques, De Deyn Peter Paul, Engelborghs Sebastiaan
Reference Center for Biological Markers of Dementia (BIODEM), and Biobank, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium.
Department of Nuclear Medicine, Hospital Network Antwerp (ZNA) Middelheim, Antwerp, Belgium.
Int J Geriatr Psychiatry. 2015 Aug;30(8):864-9. doi: 10.1002/gps.4229. Epub 2014 Nov 3.
Iodine-123 metaiodobenzylguanidine (MIBG) cardiac scintigraphy has shown the potential to discriminate dementia with Lewy bodies (DLB) from Alzheimer's disease (AD). However, these studies did not reflect clinical practice, as patients with ischemic heart disease, heart failure, diabetes mellitus, arterial hypertension, and hyperlipidemia and patients treated with antidepressants like trazodone were excluded.
This study aimed to evaluate the use of MIBG cardiac scintigraphy to diagnose DLB in clinical practice. Moreover, the potential diagnostic value of MIBG cardiac scintigraphy in patients with clinically ambiguous dementia diagnosis (DLB versus AD) was tested. Eighty-five patients with a possible clinical diagnosis of DLB entered the study. MIBG uptake was determined by calculating the heart-to-mediastinum-uptake ratio (H/M).
The average H/M ratio was 1.42 ± 0.35. The number of core features for DLB and the H/M ratio were negatively correlated (p = 0.001; r = -0.360). With an H/M ratio cutoff of 1.68 in 20 patients with clinically ambiguous dementia diagnoses (DLB versus AD) at the moment of MIBG cardiac scintigraphy, 95% (19/20) of the patients were correctly classified as compared with clinical or definite diagnosis at follow-up, with sensitivity and specificity values for diagnosing DLB of 100% (16/16) and 75% (3/4), respectively. The H/M ratio was influenced only by age (p = 0.046; r = -0.217) and gender (p = 0.024) and not by any other variable studied.
The MIBG cardiac scintigraphy H/M ratio is a possible diagnostic biomarker for DLB in routine clinical practice and might have an added diagnostic value in case of doubt between DLB and AD.
123I-间碘苄胍（MIBG）心肌闪烁显像已显示出区分路易体痴呆（DLB）与阿尔茨海默病（AD）的潜力。然而，这些研究并未反映临床实际情况，因为患有缺血性心脏病、心力衰竭、糖尿病、动脉高血压和高脂血症的患者以及接受曲唑酮等抗抑郁药治疗的患者被排除在外。
本研究旨在评估MIBG心肌闪烁显像在临床实践中诊断DLB的应用。此外，还测试了MIBG心肌闪烁显像在临床痴呆诊断不明确（DLB与AD）患者中的潜在诊断价值。85例临床可能诊断为DLB的患者进入研究。通过计算心脏与纵隔摄取比值（H/M）来确定MIBG摄取情况。
平均H/M比值为1.42±0.35。DLB的核心特征数量与H/M比值呈负相关（p = 0.001；r = -0.360）。在MIBG心肌闪烁显像时，对20例临床痴呆诊断不明确（DLB与AD）的患者采用H/M比值截断值1.68，与随访时的临床或明确诊断相比，95%（19/20）的患者被正确分类，诊断DLB的敏感性和特异性值分别为100%（16/16）和75%（3/4）。H/M比值仅受年龄（p = 0.046；r = -0.217）和性别（p = 0.024）影响，不受其他研究变量影响。
MIBG心肌闪烁显像的H/M比值可能是常规临床实践中DLB的一种诊断生物标志物，在DLB与AD难以鉴别时可能具有额外的诊断价值。
