Protective role of physical activity on type 2 diabetes: Analysis of effect modification by race–ethnicity

Background It is well known physical activity (PA) plays a role in the prevention of type 2 diabetes (T2D). However, the extent to which PA may affect T2D risk among different race–ethnic groups is unknown. Therefore, the aim of the present study was to systematically examine the effect modification of race–ethnicity on PA and T2D. Methods The PubMed and Embase databases were systematically searched through June 2016. Study assessment for inclusion was conducted in three phases: title review (n = 13 022), review (n = 2200), and full text review (n = 265). In all, 27 studies met the inclusion criteria and were used in the analysis. Relative risks (RRs) and 95% confidence intervals (CIs) were extracted and analyzed using Comprehensive Meta‐Analysis software. All analyses used a random‐effects model. Results A significant protective summary RR, comparing the most active group with the least active PA group, was found for non‐Hispanic White (RR 0.71, 95% CI 0.60–0.85), Asians (RR 0.76, 95% CI 0.67–0.85), Hispanics (RR 0.75, 95% CI 0.64–0.89), and American Indians (RR 0.73, 95% CI 0.60–0.88). The summary effect for non‐Hispanic Blacks (RR 0.91, 95% CI 0.76–1.08) was not significant. Conclusions The results of the present study indicate that PA (comparing most to least active groups) provides significant protection from T2D, with the exception of non‐Hispanic Blacks. The results also indicate a need for race–ethnicity‐specific reporting of RRs in prospective cohort studies that incorporate multiethnic samples. 摘要 背景 众所周知, 体力活动(physical activity, PA)在预防2型糖尿病(T2D)中发挥作用。然而, 目前尚未明确的是在不同的人种‐种族群体中, 哪一种PA在什么程度上可以预防T2D的风险。因此, 本研究的目的是系统调查按照人种‐种族修正的PA对T2D具有何种影响。 方法 对截至2016年6月的PubMed与EMBASE数据库进行系统检索。将纳入的研究进行3个阶段的评估:标题评估(n=13022)、摘要评估(n=2200)以及全文评估(n=265)。在这项分析中总共有27个研究达到了入选标准并用于后续分析。使用综合性的meta分析软件来提取与分析相对风险(relative risks, RRs)与95%置信区间(CIs)。所有的分析都使用随机效应模型。 结果 将PA最活跃组与最不活跃组进行比较后发现, 在非西班牙裔白人(RR为0.71, 95% CI为0.60‐0.85)、亚裔(RR为0.76, 95% CI为0.67‐0.85)、西班牙裔(RR为0.75, 95% CI为0.64‐0.89)以及美国印第安人(RR为0.73, 95% CI为0.60‐0.88)中, PA对总体RR都具有显著保护作用。在非西班牙裔黑人中没有显著的总体保护效应(RR为0.91, 95% CI为0.76‐1.08)。 结论 本研究结果表明, 除了对非西班牙裔黑人外, PA都具有显著的预防T2D作用(PA最活跃组与最不活跃组相比)。研究结果还表明在包括多种族样本的前瞻性队列研究中, 报告RRs时需要按照人种‐种族进行分组。 Highlights There is a significant and similar risk reduction associated with physical activity across race–ethnicity with the exception of non‐Hispanic Blacks. There are several physiological mechanisms that may explain this finding that require further exploration