We studied the association between episodic memory and cortical fibrillar β-amyloid pathology within twin pairs. Using telephone-administered cognitive screening of 1415 twin pairs in a population-based older Finnish Twin Cohort study, we identified 45 (mean [SD] age 72.9 [4.0] years, 40% women) cognitively discordant same-sex twin pairs (24 dizygotic and 21 monozygotic) without neurological or psychiatric disorders other than AD or mild cognitive impairment. In-person neuropsychological testing was conducted. Cortical amyloid was measured with carbon 11-labelled Pittsburgh compound B ([¹¹C]PiB) positron emission tomography imaging and quantified as the average standardized uptake value ratio in cortical regions affected in AD. Larger within-twin pair differences in verbal immediate (r = -0.42) and delayed free recall (r = -0.41), and visual delayed free recall (r = -0.46) were associated with larger within-twin pair differences in [¹¹C]PiB uptake (p’s < 0.01). Correlations were not significantly different in dizygotic and monozygotic pairs suggesting that the episodic memory-cortical amyloid relationship is not confounded by genetic effects. However, larger samples are needed to draw more definitive conclusions.

我们研究了双胞胎中情景记忆与皮质纤维状β-淀粉样蛋白病理学之间的关联。在一项基于人群的老年芬兰双胞胎队列研究中，使用电话对 1415 对双胞胎进行认知筛查，我们确定了 45 对（平均 [SD] 年龄 72.9 [4.0] 岁，40% 为女性）认知不一致的同性双胞胎（24和 21 名单卵子）没有除 AD 或轻度认知障碍以外的神经或精神疾病。进行了面对面的神经心理学测试。皮质淀粉样蛋白用碳 11 标记的匹兹堡化合物 B ([ ¹¹C]PiB) 正电子发射断层扫描成像并量化为受 AD 影响的皮层区域的平均标准化摄取值比率。更大的双胞胎内的语言即时（r = -0.42）和延迟自由回忆（r = -0.41），视觉延迟自由回忆（r = -0.46）与更大的双胞胎内差异相关[ ¹¹ C ]PiB 摄取（p < 0.01）。双卵子和单卵子对的相关性没有显着差异，这表明情景记忆-皮质淀粉样蛋白的关系不会被遗传效应混淆。然而，需要更大的样本才能得出更明确的结论。