Ellwardt Lea, Van Tilburg Theo G, Aartsen Marja J
University of Groningen, Department of Sociology and Interuniversity Center for Social Science Theory and Methodology (ICS), Grote Rozenstraat 31, 9712 TG Groningen, The Netherlands.
VU University Amsterdam, Department of Sociology, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands.
Soc Sci Med. 2015 Jan;125:107-15. doi: 10.1016/j.socscimed.2014.05.007. Epub 2014 May 9.
Stronger engagement of older adults in social activities and greater embeddedness in networks is often argued to buffer cognitive decline and lower risks of dementia. One of the explanations is that interaction with other people trains the brain, thereby enhancing cognitive functioning. However, research on the relationship between personal networks and cognitive functioning is not yet conclusive. While previous studies have focused on the size of personal networks as a proxy of cognitive stimulation, little attention has been paid to the complexity of the personal network. Adults embedded in a broad range of network relationships (i.e., various relationship types) are likely to be exposed to a wider range of stimuli than adults embedded in a homogeneous network including similar relationship types. We expect that higher numbers of personal relationship types rather than a higher number of similar contacts relate to higher levels of cognitive functioning and slower cognitive decline. Data are from the Longitudinal Aging Study Amsterdam (LASA) and include 2959 Dutch participants aged 54 to 85 at baseline in 1992 and six follow-ups covering a time span of twenty years. Cognitive functioning is assessed with the Mini-Mental State Examination (MMSE), and for network complexity we use the Social Network Index. We test our expectations using fixed-effects regression models. The results reveal that a reduction in network complexity is associated with a reduction in cognitive functioning, which is neither explained by size of the network nor by presence of specific relationship types. However, enhanced complexity has only a marginal buffering effect on decline in cognitive functioning. We conclude that network characteristics and cognitive functioning are intertwined and that their association is mostly cross-sectional in nature.
人们常认为，老年人更多地参与社交活动以及更好地融入社交网络，有助于缓冲认知衰退并降低患痴呆症的风险。一种解释是，与他人互动能训练大脑，从而增强认知功能。然而，关于个人社交网络与认知功能之间关系的研究尚无定论。此前的研究主要关注个人社交网络的规模，以此作为认知刺激的指标，而对个人社交网络的复杂性关注较少。与置身于包括类似关系类型的同质化网络中的成年人相比，置身于广泛网络关系（即各种关系类型）中的成年人可能会接触到更广泛的刺激。我们预计，个人关系类型的数量较多而非相似联系人的数量较多，与较高的认知功能水平以及较慢的认知衰退相关。数据来自阿姆斯特丹纵向老龄化研究（LASA），包括1992年基线时年龄在54至85岁之间的2959名荷兰参与者，以及涵盖二十年时间跨度的六次随访。认知功能通过简易精神状态检查表（MMSE）进行评估，对于网络复杂性，我们使用社交网络指数。我们使用固定效应回归模型来检验我们的预期。结果显示，网络复杂性的降低与认知功能的降低相关，这既不能由网络规模也不能由特定关系类型的存在来解释。然而，复杂性的增强对认知功能衰退仅具有微弱的缓冲作用。我们得出结论，网络特征与认知功能相互交织，并且它们之间的关联在本质上大多是横断面的。
