Age-associated cognitive changes in community dwelling adults

虽然有证据表明低水平的维生素D与认知能力下降有关，但维生素D受体(VDR)的作用和巨蛋白基因多态性与纵向认知变化的联系尚不清楚。利用巴尔的摩老龄化纵向研究的702名参与者的数据，我们研究了VDR基因rs11568820(CDX-2：T/C)、rs1544410(BsmI：G/A)、rs7975232(APAI：A/C)、rs731236(Taqi：G/A)和megalin(rs3755166：G/A；rs2075252：C/T；rs4668123：C/T)基因的单核苷酸多态(SNPs)与认知能力变化的关系。在潜伏期、单倍型和回归分析中，我们发现Megalin1单核苷酸多态单倍型(GCC)与女性在言语记忆、立即回忆(CVLT-List A)上的下降幅度较大有关，而在男性的延迟回忆(CVLT-Delay Recall)上下降较慢。我们还发现，巨蛋白SNP rs3755166：G/A与男女总体认知和男性言语记忆的严重下降有关。这些结果表明，维生素D受体和巨蛋白基因的多态可以改变与年龄相关的认知能力下降。 我们假设，听力损失越大，在记忆和执行功能测试中的认知测试分数越低。在巴尔的摩没有轻度认知损伤或痴呆的老年纵向研究的55年的347名参与者的横断面队列中，我们研究了听力损失和认知表现之间的联系。参与者在1990-1994年间进行了听力和认知测试。听力损失的定义是听力较好的耳朵在0.5、1、2和4 kHz的平均听力阈值。认知测试包括一个标准化的神经认知电池，其中包括精神状态、记忆、执行功能、处理速度和语言功能的测试。回归模型被用来检验听力损失和认知之间的联系，同时调整混杂因素。听力损失越大，精神状态(简易精神状态检查)、记忆(自由回忆)和执行功能(Stroop Mixed，Trail Making B)的得分越低。这些结果对考虑到潜在混杂因素、年龄的非线性影响以及排除严重听力损失的个体的分析是可靠的。听力损失25分贝导致的认知能力下降相当于年龄相差6.8岁造成的认知能力下降。听力损失与记忆和执行功能测试的低分独立相关。 以前的研究表明，消极的自我刻板印象对边缘化群体成员的认知表现有不利影响；然而，这些发现仅限于短期实验。我们研究了刻板印象是否会随着时间的推移预测记忆，这是以前没有研究过的。我们还考虑了自我关联性是否会随着时间的推移增加刻板印象对记忆的影响。在巴尔的摩老龄化纵向研究的395名参与者的多波记忆表现数据中，我们考察了个体成长模型作为负面年龄刻板印象的函数。我们发现，在38年的时间里，那些具有较多负面年龄刻板印象的人比那些具有较少负面年龄刻板印象的人表现出明显更差的记忆表现。对于60岁及以上的人来说，年龄刻板印象较负面的组比年龄刻板印象较轻的组记忆能力下降30.2%。此外，年龄刻板印象对记忆的影响在那些年龄刻板印象与自己相关的人中明显更大。这项研究表明，负面自我刻板印象对认知表现的负面影响并不局限于短期的实验室效应。相反，这些发现第一次表明，刻板印象还可以预测社区中较长一段时间的记忆表现。

Although there is evidence for an association between low levels of Vitamin D and cognitive decline, the role of Vitamin D receptor (VDR) and the megalin gene polymorphism's link with longitudinal cognitive change has been unclear. Using data from 702 participants in the Baltimore Longitudinal Study of Aging, we examined the associations of single nucleotide polymorphisms (SNPs) for VDR rs11568820 (CdX-2:T/C), rs1544410 (BsmI:G/A), rs7975232 (ApaI:A/C), rs731236 (TaqI:G/A), and Megalin (rs3755166:G/A; rs2075252:C/T; rs4668123:C/T) genes with changes in cognitive performance. In latent class, haplotype, and regression analyses we found the Megalin1 single nucleotide polymorphism haplotype (GCC) was related to greater decline among women in verbal memory, immediate recall (CVLT-List A), but slower decline among men in delayed recall (CVLT-Delayed recall). We also found that the Megalin SNP rs3755166:G/A was associated with greater decline in global cognition in both sexes combined and in verbal memory in men. These results suggest that the vitamin D receptor and the megalin polymorphism modifies age-related cognitive decline. We hypothesized that greater hearing loss was associated with lower cognitive test scores on tests of memory and executive function. In a cross-sectional cohort of 347 participants >= 55 years from the Baltimore Longitudinal Study of Aging without mild cognitive impairment or dementia we examined the association of hearing loss and cognitive performance. Participants had audiometric and cognitive testing performed in 1990-1994. Hearing loss was defined by an average of hearing thresholds at 0.5, 1, 2, and 4 kHz in the better-hearing ear. Cognitive testing consisted of a standardized neurocognitive battery incorporating tests of mental status, memory, executive function, processing speed, and verbal function. Regression models were used to examine the association between hearing loss and cognition while adjusting for confounders. Greater hearing loss was significantly associated with lower scores on measures of mental status (Mini-Mental State Exam), memory (Free Recall), and executive function (Stroop Mixed, Trail Making B). These results were robust to analyses accounting for potential confounders, nonlinear effects of age, and exclusion of individuals with severe hearing loss. The reduction in cognitive performance associated with a 25 dB hearing loss was equivalent to the reduction associated with an age difference of 6.8 years. Hearing loss is independently associated with lower scores on tests of memory and executive function. Previous studies showed that negative self-stereotypes detrimentally affect the cognitive performance of marginalized group members; however, these findings were confined to short-term experiments. We examined whether stereotypes predicted memory over time, which had not been previously examined. We also considered whether self-relevance increased the influence of stereotypes on memory over time. In data from multiple waves of memory performance from 395 participants in the Baltimore Longitudinal Study of Aging, we examined individual growth models as a function of negative age stereotypes. We found that those with more negative age stereotypes demonstrated significantly worse memory performance over 38 years than those with less negative age stereotypes. The decline in memory performance for those aged 60 and above was 30.2% greater for the more negative age stereotype group than for the less negative age stereotype group. Also, the impact of age stereotypes on memory was significantly greater among those for whom the age stereotypes were self-relevant. This study shows that the adverse influence of negative self-stereotypes on cognitive performance is not limited to a short-term laboratory effect. Rather, the findings demonstrate, for the first time, that stereotypes also predict memory performance over an extended period in the community.