Data from: Leisure-time physical activity and dementia risk: a dose-response meta-analysis of prospective studies

Background: Considerable evidences were indicative of favorable roles of physical activity (PA) in fighting against dementia. However, the shape of dose–response relationship has not been explored. Objective: To conduct a meta-analysis to quantitatively investigate the relationship of dementia with PA by metabolic equivalent of task (MET)-hour/week and kilocalorie (kcal)/week. Design: Prospective studies published from Jan 1, 1995 to August 2016 were searched in PubMed, EMBASE, Ovid and the Cochrane Library. Two meta-analyses were performed with the focus on exploring the dose-response relationship using two-stage generalized least squares regression. Results: The qualitative analysis showed a trend of dose-response relationship with all-cause of dementia (ACD), Alzheimer’s disease (AD) but not vascular dementia (VD). In the dose-response analysis, ACD (p-trend<0.005; p-nonlinearity=0.87) and AD (p-trend<0.005; p-nonlinearity= 0.10) exhibited a linear relationship with leisure-time PA (LTPA) over the observed range (0-2000 kcal/week or 0–45 MET-h/week). Specifically, for every 500 kcal or 10 MET-h increase per week, the decrement of risk is roughly 10% (95%CI, 0.85-0.97) for ACD and 13% (95%CI, 0.79-0.96) for AD. Conclusions: We for the first time proved the dose-response relationship between LTPA and dementia/AD, which finding further supported the international PA guideline from a standpoint of dementia prevention.

研究背景：已有大量证据表明，体力活动（physical activity, PA）在对抗痴呆症方面具有积极作用，但目前尚未明确其与痴呆风险之间的剂量-反应关系的具体形态。
研究目的：开展一项荟萃分析，以每周代谢当量（metabolic equivalent of task, MET）-小时数和千卡（kilocalorie, kcal）为量化指标，定量探究体力活动与痴呆症之间的关联。
研究设计：检索1995年1月1日至2016年8月发表于PubMed、EMBASE、Ovid及Cochrane图书馆的前瞻性研究。采用两阶段广义最小二乘回归法开展两项荟萃分析，重点探究体力活动与痴呆的剂量-反应关系。
研究结果：定性分析显示，体力活动与全因痴呆（all-cause dementia, ACD）、阿尔茨海默病（Alzheimer’s disease, AD）存在潜在的剂量-反应关系，但未观察到与血管性痴呆（vascular dementia, VD）存在此类关联。剂量-反应分析结果表明，在观测范围内（0~2000 kcal/周或0~45 MET-小时/周），全因痴呆（p趋势<0.005；p非线性=0.87）与阿尔茨海默病（p趋势<0.005；p非线性=0.10）均与闲暇时间体力活动（leisure-time PA, LTPA）呈线性相关。具体而言，每周体力活动每增加500千卡或10 MET-小时，全因痴呆的发病风险可降低约10%（95%置信区间：0.85~0.97），阿尔茨海默病的发病风险可降低约13%（95%置信区间：0.79~0.96）。
研究结论：本研究首次证实了闲暇时间体力活动与痴呆症/阿尔茨海默病之间的剂量-反应关系，该发现从痴呆症预防的角度进一步支持了国际体力活动指南。