Hickman Ruby C, Wang Herong, Brandt Daniel J, Ware Erin B, Bakulski Kelly M
Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, Michigan, USA.
Survey Research Center, Institute for Social Research, University of Michigan, Ann Arbor, Michigan, USA.
medRxiv. 2024 Nov 11:2024.11.11.24317122. doi: 10.1101/2024.11.11.24317122.
This study assessed whether self-rated physical and mental work demands were associated with cognition among older working adults and whether their effects were dependent.
Our cross-sectional sample consisted of 6,377 working older adults uisng the Health and Retirement Study in 2004. Self-rated work demands were summarized from four questions about frequency of mental or physical demands in the respondent's current job. Cognition was assessed using a subset of the Telephone Interview for Cognitive Status. We used multivariable linear regression to test for associations and additive interaction between physical and mental work demands and cognition, adjusted for age, sex, race, education, and practice effect.
Independently, higher physical work demands were associated <0.001 with poorer cognition and higher mental work demands were associated (<0.001) with better cognition. The effect of one work demand measure became more negative as level of the other increased (B for interaction = -0.23, 95% CI: -0.43, -0.03). A one-point increase in mental work demands was associated with 0.79 (95% CI: 0.51, 1.08) points higher cognition score when physical work demands were lowest, but was not associated with cognition when physical work demands were highest (0.11, 95% CI: -0.26, 0.48). The highest predicted cognition score was for the highest mental and lowest physical work demands. Results were robust to additional adjustment for health and behavior covariates.
The associations of self-rated mental and physical work demands on cognition are dependent. Future studies should strongly consider examining interactions to capture the range of work demand effects.
本研究评估了自评的体力和脑力工作需求是否与老年在职成年人的认知能力相关，以及它们的影响是否相互依赖。
我们的横断面样本包括2004年使用健康与退休研究的6377名老年在职成年人。自评工作需求是根据关于受访者当前工作中脑力或体力需求频率的四个问题汇总得出的。认知能力使用认知状态电话访谈的一个子集进行评估。我们使用多变量线性回归来测试体力和脑力工作需求与认知能力之间的关联以及相加交互作用，并对年龄、性别、种族、教育程度和练习效应进行了调整。
单独来看，较高的体力工作需求与较差的认知能力相关（<0.001），较高的脑力工作需求与较好的认知能力相关（<0.001）。一种工作需求衡量指标的影响随着另一种指标水平的增加而变得更负面（交互作用的B值 = -0.23，95%置信区间：-0.43，-0.03）。当体力工作需求最低时，脑力工作需求增加一分与认知得分高0.79分（95%置信区间：0.51，1.08）相关，但当体力工作需求最高时，与认知能力无关（0.11，95%置信区间：-0.26，0.48）。预测的最高认知得分是脑力工作需求最高且体力工作需求最低时的得分。对健康和行为协变量进行额外调整后，结果依然稳健。
自评的脑力和体力工作需求与认知能力之间的关联是相互依赖的。未来的研究应大力考虑检验交互作用，以全面了解工作需求效应的范围。
