DAT imaging and myocardial MIBG scintigraphy for Lewy body diseases: A clinical‐neuroimaging study

Abstract

Objectives Neuroimaging markers for Lewy body diseases (LBDs) include dopamine transporter (DAT) scanning and metaiodobenzylguanidine (MIBG) myocardial scintigraphy. It is unknown which marker is more useful for identifying the three major LBD subtypes: Parkinson's disease (PD), dementia with Lewy bodies (DLB), and the autonomic‐sleep variant. To answer this question, we analyzed clinical‐neuroimaging data of 450 LBD patients. Methods This study was a prospective cohort study with a recruiting period of 3.0 years, prospective follow‐up period of 2.0 ± 1.8 years, and visits at least once a year. We recruited 745 referred subjects who had undergone both DAT and MIBG tests, and the inclusion criteria accorded with published criteria of PD, DLB, and the autonomic/sleep variant (at least one of PD/DLB's known early features: orthostatic hypotension, constipation, overactive bladder, and REM sleep behavior disorder [RBD]). Results A total of 450 patients fulfilled the criteria. Among the LBD subtypes, the most common was PD (49.3%), followed by DLB (46.4%) and the autonomic/sleep variant (4.2%). DAT and MIBG tests were almost equally abnormal in PD (98.2%, 79.3%, respectively); however, between the two measures, DAT was more frequently abnormal in DLB (82.3%, 56.9%, respectively) and MIBG in the autonomic/sleep variant (57.9%, 94.7%, respectively). Still, these differences did not reach statistical significance. Conclusion Between the two neuroimaging tests, the DAT scan tended to parallel brain disease (PD/DLB), while the MIBG test tended to parallel peripheral disease (autonomic/sleep variant).

Prevalence of triple/dual disease (Alzheimer's disease, Lewy body disease, and white matter disease)

“…(b) For DLB, fulfilling the published criteria (ie, McKeith's criteria: Fourth consensus report of the DLB Consortium), 3 in these criteria, positivity on both MIBG myocardial scintigraphy and dopamine transporter (DAT) scan is supportive criteria. ( c ) Autonomic‐sleep variant was defined according to our previous paper 4,9 . We added at least one positive finding either in MIBG scan or DAT scan to the inclusion criteria.…”

“…90%) 10 ; and an MIBG test, that is, noradrenergic denervation in the heart and a delayed heart to mediastinum ratio <2.0 suggesting LBD (specificity and sensitivity around 90%) 11 . The imaging acquisition in these scans was performed according to the method described in our previous study 4 …”

“…(c) Autonomic-sleep variant was defined according to our previous paper. 4,9 We added at least one positive finding either in MIBG scan or DAT scan to the inclusion criteria. None of the patients had heart failure or diabetic neuropathy, and none were taking drugs that potentially interfere with neuroimaging.…”

“…11 The imaging acquisition in these scans was performed according to the method described in our previous study. 4 We also measured, in selected patients, cerebrospinal fluid biological markers (tau, beta-amyloid, and alpha-synuclein 12 ) to confirm the clinical diagnosis if necessary. We did not perform a smell test.…”

“…Alzheimer's disease (AD), 1 Lewy body diseases (LBDs, comprising Parkinson's disease [PD], 2 dementia with Lewy bodies [DLB], 3 and the autonomic‐sleep variant 4 ), and white matter disease (WMD) 5,6 are common in the elderly. Although two or more of these three diseases are sometimes observed together in pathology examinations, 7,8 it is uncertain to what extent the diseases occur together clinically.…”