Abstract：
Despite altered brain activities being associated with suicidal ideation (SI), the neural correlates of SI in major depressive disorder (MDD) have remained elusive. We enrolled 82 first-episode drug-naïve MDD patients including 41 with SI and 41 without SI, as well as 41 healthy controls (HCs). Resting-state functional and structural MRI data were collected. The measures of fractional amplitude of low-frequency fluctuation (fALFF) and grey matter volume (GMV) were calculated and compared. Compared with HCs, patients with SI exhibited increased fALFF values in the right rectus gyrus and left medial superior frontal gyrus, middle frontal gyrus and precuneus. Decreased GMV in the right parahippocampal gyrus, insula and middle occipital gyrus and increased GMV in the left superior frontal gyrus were detected in patients with SI. In addition, patients without SI demonstrated increased fALFF values in the right superior frontal gyrus and decreased fALFF values in the right postcentral gyrus. Decreased GMV in the left superior frontal gyrus, right medial superior frontal gyrus, opercular part of inferior frontal gyrus, postcentral gyrus, fusiform gyrus and increased left supplementary motor area, superior occipital gyrus, right anterior cingulate gyrus and superior temporal gyrus were revealed in patients with SI. Moreover, in comparison with patients without SI, increased fALFF values were identified in the left precuneus of patients with SI. However, no significant differences were found in GMV between patients with and without SI. These findings might be helpful for finding neuroimaging markers predicting individual suicide risk and detecting targeted brain regions for effective early interventions.
摘要：
尽管大脑活动的改变与自杀意念（SI）有关，严重抑郁障碍（MDD）中SI的神经相关性仍然难以捉摸。我们招募了82例首发药物初治MDD患者，包括41例SI和41例无SI，以及41名健康对照（HCs）。收集静息状态的功能和结构MRI数据。计算并比较了低频波动（fALFF）和灰质体积（GMV）的幅度分数。与HC相比，患有SI的患者在右直肌回和左额上内侧回表现出增加的fALFF值,额中回和前回。右侧海马旁回的GMV降低,在SI患者中检测到岛和枕中回以及左额上回的GMV增加。此外,无SI的患者显示右额上回的fALFF值升高,右中央后回的fALFF值降低.左额上回GMV降低,右内侧上额回,下额回的眼部,中央后回,梭状回和左补充运动面积增加，枕上回,SI患者可见右前扣带回和颞上回。此外，与没有SI的患者相比，在SI患者的左前肌中发现fALFF值增加。然而,在有和无SI的患者之间，GMV没有发现显着差异。这些发现可能有助于找到预测个体自杀风险的神经影像学标记物，并检测有效早期干预的目标大脑区域。
