Boakye Daniel, Jansen Lina, Schöttker Ben, Jansen Eugene H J M, Halama Niels, Maalmi Haifa, Gào Xin, Chang-Claude Jenny, Hoffmeister Michael, Brenner Hermann
Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ), Heidelberg, Germany.
Network of Aging Research, Heidelberg University, Heidelberg, Germany.
Am J Clin Nutr. 2021 Jun 1;113(6):1458-1467. doi: 10.1093/ajcn/nqaa405.
Vitamin D plays a role in detoxifying free radicals, which might explain the previously reported lower mortality in colorectal cancer (CRC) patients with higher vitamin D concentrations.
We aimed to assess whether the associations of 25-hydroxyvitamin D [25(OH)D] with prognosis in CRC patients differ by total thiol concentration (TTC), a biomarker of antioxidant capacity.
CRC patients who were diagnosed from 2003 to 2010 and recruited into a population-based study in southern Germany (n = 2,592) were followed over a period of 6 y. 25(OH)D and TTC were evaluated from blood samples collected shortly after CRC diagnosis. Associations of 25(OH)D with all-cause and CRC mortality according to TTC were estimated using multivariable Cox proportional hazards regression.
There was a weak positive correlation between 25(OH)D and TTC (r = 0.26, P < 0.001). 25(OH)D was inversely associated with mortality among patients in the lowest and middle TTC tertiles, but no associations were found among patients in the highest TTC tertile (P-interaction = 0.01). Among patients in the lowest/middle TTC tertiles, those in the middle and highest (compared with lowest) 25(OH)D tertiles had 31% and 44% lower all-cause mortality (P < 0.001) and 25% and 45% lower CRC mortality (P < 0.001), respectively. However, in the highest TTC tertile, 25(OH)D was not associated with all-cause (P = 0.638) or CRC mortality (P = 0.395).
The survival advantages in CRC patients with adequate vitamin D strongly depend on antioxidant capacity and are most pronounced in cases of low antioxidant capacity. These findings suggest that TTC and other biomarkers of antioxidant status may be useful as the basis for enhanced selection criteria of patients for vitamin D supplementation, in addition to the conventional judgment based on blood 25(OH)D concentrations, and also for refining selection of patients for clinical trials aiming to estimate the effect of vitamin D supplementation.
维生素D在清除自由基方面发挥作用，这可能解释了先前报道的维生素D浓度较高的结直肠癌（CRC）患者死亡率较低的现象。
我们旨在评估25-羟基维生素D[25(OH)D]与CRC患者预后的关联是否因总硫醇浓度（TTC）而异，TTC是抗氧化能力的生物标志物。
对2003年至2010年诊断并纳入德国南部一项基于人群的研究的CRC患者（n = 2592）进行了6年的随访。在CRC诊断后不久采集的血样中评估25(OH)D和TTC。使用多变量Cox比例风险回归估计根据TTC的25(OH)D与全因死亡率和CRC死亡率的关联。
25(OH)D与TTC之间存在弱正相关（r = 0.26，P < 0.001）。在TTC最低和中间三分位数的患者中，25(OH)D与死亡率呈负相关，但在TTC最高三分位数的患者中未发现关联（P交互作用 = 0.01）。在TTC最低/中间三分位数的患者中，25(OH)D处于中间和最高（与最低相比）三分位数的患者全因死亡率分别降低31%和44%（P < 0.001），CRC死亡率分别降低25%和45%（P < 0.001）。然而，在TTC最高三分位数中，25(OH)D与全因死亡率（P = 0.638）或CRC死亡率（P = 0.395）无关。
维生素D充足的CRC患者的生存优势很大程度上取决于抗氧化能力，在抗氧化能力低的情况下最为明显。这些发现表明，TTC和其他抗氧化状态生物标志物除了可作为基于血液25(OH)D浓度的传统判断之外，还可作为增强维生素D补充患者选择标准的基础，也可用于优化旨在评估维生素D补充效果的临床试验患者的选择。
