Background and aim

Whether cerebral microbleeds (CMBs) cause cognitive impairment remains uncertain. We analysed whether CMBs are associated with cognitive dysfunction in patients with symptomatic cerebral small vessel disease (cSVD), and whether this association is independent of other cSVD neuroimaging markers.

Methods

We analysed consecutive patients with MRI-confirmed lacunar stroke included in DNA-Lacunar-2 multicentre study. CMBs were graded using the Brain Observer Microbleed Rating Scale (BOMBS). Neuropsychological assessment was performed using the Brief Memory and Executive Test (BMET). We analysed the association between CMBs, BMET and the following subdomains: executive function/processing speed (EF/PS) and orientation/memory (O/M). We also searched for an independent association between CMBs and vascular cognitive impairment (VCI), defined as BMET≤13.

Results

Out of 688 included patients, CMBs were detected in 192 (27.9%). After adjusting for WMH severity, lacune count and other confounders, both the presence and number of CMBs were significantly associated with impaired cognitive performance [β=-13.0; 95%CI= (-25.3;-0.6) and β=-13.1; 95%CI= (-19.8;-6.4), respectively]. On analysis of specific cognitive domains, associations were present for EF/PS [β=-5.8; 95%CI= (-9.3;-2.2) and β=-4.3; 95%CI= (-6.2;-2.4), respectively] but not for O/M [β=-0.4; 95%CI= (-4.0;3.2) and β=-2.1; 95%CI= (-4.0;0.1), respectively]. We also found an independent association between the presence and number of CMBs and VCI [adjusted OR=1.48; 95%CI= (1.01;2.18) and OR=1.43; 95%CI= (1.15;1.79), respectively).

Conclusion

In a large cohort of symptomatic cSVD patients, after controlling for other neuroimaging markers of cSVD severity, CMBs were associated with cognitive dysfunction. Executive function and processing speed were predominantly impaired. This might suggest a causal role of CMBs in determining VCI.

背景和目标

脑微出血 (CMB) 是否会导致认知障碍仍不确定。我们分析了 CMB 是否与症状性脑小血管疾病 (cSVD) 患者的认知功能障碍相关，以及这种关联是否独立于其他 cSVD 神经影像学标志物。

方法

我们分析了包括在 DNA-Lacunar-2 多中心研究中的 MRI 证实的腔隙性卒中的连续患者。使用大脑观察者微出血评定量表 (BOMBS) 对 CMB 进行分级。使用简要记忆和执行测试（BMET）进行神经心理学评估。我们分析了 CMB、BMET 和以下子域之间的关联：执行功能/处理速度 (EF/PS) 和方向/记忆 (O/M)。我们还搜索了 CMBs 和血管认知障碍 (VCI)，定义为 BMET 13 之间的独立关联。

结果

在纳入的 688 名患者中，192 名 (27.9%) 检测到 CMB。在调整 WMH 严重程度、腔隙计数和其他混杂因素后，CMB 的存在和数量都与认知能力受损显着相关 [β=-13.0; 95%CI= (-25.3;-0.6) 和 β=-13.1; 95% CI = (-19.8;-6.4)，分别]。在对特定认知领域的分析中，存在 EF/PS [β=-5.8; 95%CI= (-9.3;-2.2) 和 β=-4.3; 95%CI= (-6.2;-2.4), 分别] 但不适用于 O/M [β=-0.4; 95%CI= (-4.0;3.2) 和 β=-2.1；95%CI = (-4.0;0.1)，分别]。我们还发现 CMB 的存在和数量与 VCI 之间存在独立关联 [调整后的 OR=1.48；95%CI= (1.01;2.18) 和 OR=1.43；95%CI = (1.15;1.79)，分别）。

结论

在一大群有症状的 cSVD 患者中，在控制了 cSVD 严重程度的其他神经影像学标志物后，CMB 与认知功能障碍相关。执行功能和处理速度主要受损。这可能表明 CMB 在确定 VCI 中的因果作用。