Department of Health Preservation and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China.
Department of Physical Education, Chongqing University of Arts and Sciences, Chongqing, China.
PLoS One. 2023 Aug 1;18(8):e0289252. doi: 10.1371/journal.pone.0289252. eCollection 2023.
Observational studies suggest physical activity (PA) enhances intelligence, while sedentary behavior (SB) poses a risk. However, causality remains unclear.
We extracted genetic instruments from large genome-wide association studies summary data and employed an inverse-variance weighted (IVW) approach within a random-effects model as the primary method of Mendelian randomization (MR) analysis to estimate the overall effect of various physical activity statuses on intelligence. To assess IVW stability and MR sensitivity, we also utilized supplementary methods including weighted median, MR-Egger, and MR-PRESSO. Furthermore, multivariable MR analysis was conducted to examine the independent effects of each physical activity trait on intelligence.
The MR primary results indicated that LST was negatively associated with intelligence (β = -0.133, 95%CI: -0.177 to -0.090, p = 1.34×10-9), while SBW (β = 0.261, 95% CI: 0.059 to 0.463, p = 0.011) may have a positive effect on intelligence; however, MVPA and SC did not show significant effects on intelligence. Inverse causality analyses demonstrated intelligence significantly influenced all physical activity states.
Our study highlights a bidirectional causal relationship between physical activity states and intelligence.
观察性研究表明，身体活动（PA）可提高智力，而久坐行为（SB）则会带来风险。然而，因果关系尚不清楚。
我们从大型全基因组关联研究汇总数据中提取遗传工具，并在随机效应模型中采用逆方差加权（IVW）方法作为孟德尔随机化（MR）分析的主要方法，以估计各种身体活动状态对智力的总体影响。为了评估 IVW 的稳定性和 MR 的敏感性，我们还使用了加权中位数、MR-Egger 和 MR-PRESSO 等补充方法。此外，还进行了多变量 MR 分析，以检验每个身体活动特征对智力的独立影响。
MR 主要结果表明，LST 与智力呈负相关（β=-0.133，95%CI：-0.177 至 -0.090，p=1.34×10-9），而 SBW（β=0.261，95%CI：0.059 至 0.463，p=0.011）可能对智力有正向影响；然而，MVPA 和 SC 对智力没有显著影响。反向因果关系分析表明，智力显著影响所有身体活动状态。
本研究强调了身体活动状态与智力之间存在双向因果关系。
