Winqvist Satu, Kärppä Mikko, Moilanen Jukka S, Majamaa Kari
Neurocenter, Oulu University Hospital, Oulu, Finland.
Medical Research Center Oulu, Oulu University Hospital, Oulu, Finland.
BMC Neurol. 2025 Jul 31;25(1):316. doi: 10.1186/s12883-025-04325-y.
The m.3243A>G variant in mitochondrial DNA is associated with a wide spectrum of clinical features ranging from asymptomatic subjects to severely symptomatic patients. Cognitive involvement is one of the clinical features, but its severity and frequency are not properly known. Here we describe neuropsychological features associated with m.3243 A > G.
We studied 45 adult patients with m.3243 A > G and 45 healthy subjects. Comprehensive neuropsychological test battery was applied. Cognitive impairment was defined, if at least five out of seven cognitive domains were impaired compared to matched controls. Major cognitive impairment was diagnosed, if the impairment was general across the domains.
Sixteen patients (36%) with m.3243 A > G were diagnosed with cognitive impairment, and six of them (13%) had a major cognitive impairment. The median age at diagnosis of cognitive impairment was 53 years (range, 25-64). The profile consisted of impaired abstract reasoning, memory problems, motor function defects and executive problems. Executive functions were affected most, and verbal memory was affected the least. Higher variant heteroplasmy and more severe global phenotype were associated with cognitive impairment, whereas age and sex were not.
Cognitive impairment is found frequently in patients with m.3243 A > G, but major cognitive impairment is not common. The impairment affects all neuropsychological domains and no specific profile could be identified.
线粒体DNA中的m.3243A>G变异与广泛的临床特征相关，范围从无症状个体到症状严重的患者。认知受累是临床特征之一，但其严重程度和发生率尚不清楚。在此，我们描述与m.3243A>G相关的神经心理学特征。
我们研究了45例患有m.3243A>G的成年患者和45名健康受试者。应用了全面的神经心理测试组。如果与匹配的对照组相比，七个认知领域中至少有五个受损，则定义为认知障碍。如果障碍在各领域普遍存在，则诊断为重度认知障碍。
16例（36%）患有m.3243A>G的患者被诊断为认知障碍，其中6例（13%）患有重度认知障碍。认知障碍诊断时的中位年龄为53岁（范围25-64岁）。特征包括抽象推理受损、记忆问题、运动功能缺陷和执行问题。执行功能受影响最大，言语记忆受影响最小。较高的变异异质性和更严重的整体表型与认知障碍相关，而年龄和性别则无关。
m.3243A>G患者中经常发现认知障碍，但重度认知障碍并不常见。该障碍影响所有神经心理领域，且无法确定特定的特征。
