Miller Jeffrey M, Everett Benjamin A, Oquendo Maria A, Ogden R Todd, Mann J John, Parsey Ramin V
Division of Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, New York.
Department of Psychiatry, Columbia University, New York, New York.
Synapse. 2016 Jan;70(1):24-32. doi: 10.1002/syn.21868. Epub 2015 Oct 19.
Bipolar disorder (BD) is associated with abnormalities in the serotonin transporter (5-HTT), but specific in vivo findings have been discrepant. Using positron emission tomography (PET) and [(11)C]DASB, we compared 5-HTT binding between unmedicated depressed BD subjects and healthy volunteers (HVs).
5-HTT binding in six brain regions was compared between 17 depressed, unmedicated BD subjects and 31 HVs, using the outcome measure of VT/fP (proportional to the total number of available transporters). Alternative outcome measures were examined as well. 47% of BD were BP I; and 65% reported a prior suicide attempt.
5-HTT binding (VT/fP ) did not differ between BD and HV groups considering six brain regions of interest simultaneously (P = 0.24). In contrast, alternative outcome measures (BPF*, BPP*, and BPND*) indicated lower binding in BD compared with HV across these six regions of interest (BPF*: P = 0.047; BPP*: P = 0.032; BPND*: P = 0.031). 5-HTT binding was unrelated to suicide attempt history, depression severity, bipolar subtype, or history of past substance use disorder.
Choice of outcome measure strongly affects comparisons of serotonin transporter binding using PET with [(11)C]DASB. We do not find evidence of abnormal 5-HTT binding in bipolar depression using our primary outcome measure, VT /fP . However, we did observe lower 5-HTT binding in BD with alternative outcome measures that are frequently used with [(11)C]DASB. Relative merits and assumptions of different outcome measures are discussed. Evaluation in larger samples and during different mood states, including remission, is warranted.
双相情感障碍（BD）与血清素转运体（5-HTT）异常有关，但具体的体内研究结果存在差异。我们使用正电子发射断层扫描（PET）和[(11)C]DASB，比较了未用药的抑郁BD患者与健康志愿者（HV）之间的5-HTT结合情况。
使用VT/fP（与可用转运体总数成比例）作为结果指标，比较了17名未用药的抑郁BD患者和31名HV在六个脑区的5-HTT结合情况。还检查了其他结果指标。47%的BD患者为双相I型；65%的患者报告有过自杀未遂史。
同时考虑六个感兴趣的脑区时，BD组和HV组之间的5-HTT结合（VT/fP）没有差异（P = 0.24）。相比之下，其他结果指标（BPF*、BPP和BPND）表明，在这六个感兴趣的区域中，BD患者的结合低于HV（BPF*：P = 0.047；BPP*：P = 0.032；BPND*：P = 0.031）。5-HTT结合与自杀未遂史、抑郁严重程度、双相亚型或过去物质使用障碍史无关。
结果指标的选择强烈影响使用PET和[(11)C]DASB对血清素转运体结合的比较。使用我们的主要结果指标VT /fP，我们没有发现双相抑郁中5-HTT结合异常的证据。然而，我们确实观察到，使用[(11)C]DASB常用的其他结果指标时，BD患者的5-HTT结合较低。讨论了不同结果指标的相对优点和假设。有必要在更大样本和不同情绪状态（包括缓解期）下进行评估。
