Department of Nutrition, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong Province, China.
Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Guangzhou, Guangdong Province, China.
Am J Clin Nutr. 2022 Oct 6;116(4):1070-1077. doi: 10.1093/ajcn/nqac170.
Indole-3-propionic acid (IPA), a microbiota-produced tryptophan metabolite, has been shown to exhibit cardioprotective effects in animal models. However, the relation of IPA with cardiovascular risk in humans is currently unknown.
This prospective study aimed to investigate whether plasma tryptophan and IPA levels are associated with decreased risks of mortality.
Ultra-HPLC-MS/MS was used to measure plasma tryptophan and IPA levels in 1829 patients with coronary artery disease (CAD). Cox proportional hazards regression models were used to estimate the associations between tryptophan and IPA levels and the risks of cardiovascular and all-cause mortality.
During the median 9.2-year follow-up, 424 all-cause deaths occurred, of which 272 were cardiovascular deaths. Plasma tryptophan and IPA levels were significantly associated with reduced risks of cardiovascular and all-cause mortality. Patients with CAD with the highest quartiles of tryptophan and IPA levels had multivariable-adjusted HRs of 0.62 (95% CI, 0.43-0.89) and 0.71 (95% CI, 0.50-0.99), respectively, for cardiovascular mortality and 0.67 (95% CI, 0.50-0.90) and 0.75 (95% CI, 0.57-0.99), respectively, for all-cause mortality compared with those in patients with CAD in the lowest quartile. After multivariable adjustments, 1-SD increases in the continuous plasma tryptophan and IPA levels were associated with 16% and 14% decreases, respectively, in the risks of cardiovascular mortality and with 13% and 14% decreases, respectively, in the risks of all-cause mortality. Restricted cubic splines displayed linear associations between plasma tryptophan and IPA levels and cardiovascular and all-cause mortality among patients with CAD.
Our findings suggest that plasma tryptophan and IPA levels are significantly associated with decreased risks of cardiovascular and all-cause mortality in patients with CAD. Further studies are needed to determine the clinical diagnostic and therapeutic values of tryptophan and IPA levels on the risks of mortality among patients with CAD.
吲哚-3-丙酸（IPA）是一种由微生物群产生的色氨酸代谢物，已在动物模型中显示出心脏保护作用。然而，IPA 与人类心血管风险的关系目前尚不清楚。
本前瞻性研究旨在探讨血浆色氨酸和 IPA 水平是否与降低死亡率风险相关。
使用超高效液相色谱-串联质谱法（UPLC-MS/MS）测量 1829 例冠心病（CAD）患者的血浆色氨酸和 IPA 水平。使用 Cox 比例风险回归模型估计色氨酸和 IPA 水平与心血管和全因死亡率风险之间的关联。
在中位 9.2 年的随访期间，发生了 424 例全因死亡，其中 272 例为心血管死亡。血浆色氨酸和 IPA 水平与降低心血管和全因死亡率风险显著相关。IPA 水平最高四分位数的 CAD 患者的多变量校正 HR 分别为 0.62（95%CI，0.43-0.89）和 0.71（95%CI，0.50-0.99），心血管死亡率和全因死亡率分别为 0.67（95%CI，0.50-0.90）和 0.75（95%CI，0.57-0.99）。与 IPA 水平最低四分位数的 CAD 患者相比。经多变量调整后，连续血浆色氨酸和 IPA 水平每增加 1-SD，心血管死亡率风险分别降低 16%和 14%，全因死亡率风险分别降低 13%和 14%。受限立方样条显示 CAD 患者的血浆色氨酸和 IPA 水平与心血管和全因死亡率之间存在线性关联。
我们的研究结果表明，血浆色氨酸和 IPA 水平与 CAD 患者的心血管和全因死亡率风险显著降低相关。需要进一步的研究来确定色氨酸和 IPA 水平对 CAD 患者死亡率风险的临床诊断和治疗价值。
