Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sung Kyunkwan University School of Medicine, Seoul, Korea.
Department of Thoracic and Cardiovascular Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
PLoS One. 2019 Dec 18;14(12):e0225720. doi: 10.1371/journal.pone.0225720. eCollection 2019.
Serum phosphorus is a well-known marker of vascular calcification, but the effects of serum phosphorus abnormalities defined by clinical criteria on the outcomes of coronary artery bypass grafting (CABG) remain unclear. We aimed to evaluate whether preoperative serum phosphorus abnormalities defined based on clinical criteria are associated with outcomes of CABG using a relatively new statistical technique, inverse probability weighting (IPW) adjustment.
From January 2001 to December 2014, 4,989 consecutive patients who underwent CABG were stratified into normal (2.5-4.5 mg/dl; n = 4,544), hypophosphatemia (<2.5 mg/dl; n = 238), or hyperphophatemia (>4.5 mg/dl; n = 207) groups depending on preoperative serum phosphorus level.
The primary outcome was all-cause death during a median follow-up of 48 months. Secondary outcomes were cardiovascular death, graft failure, myocardial infarction, repeat revascularization, and stroke. In multivariate Cox analysis, preoperative hypophosphatemia was significantly associated with all-cause death (hazard ratio [HR] 1.76; 95% confidence interval [CI] 1.13-2.76; P = 0.01). However, this association varied depending on chronic kidney disease and emergent operation (p for interaction = 0.05 and 0.03, respectively). In addition, analysis after IPW adjustment demonstrated that preoperative serum phosphorus abnormalities were not significantly associated with all-cause death (P = 0.08) or any secondary outcomes except graft failure. Graft failure was significantly associated with preoperative hypophosphatemia (HR 2.51; 95% CI 1.37-4.61; P = 0.003).
Our study showed that preoperative serum phosphorus abnormalities in clinical criteria were not associated with outcomes after CABG except for graft failure. And, the association of hypophosphatemia with graft failure remains to be evaluated.
血清磷是血管钙化的一个众所周知的标志物，但临床标准定义的血清磷异常对冠状动脉旁路移植术（CABG）结局的影响尚不清楚。我们旨在使用一种相对较新的统计技术，即逆概率加权（IPW）调整，评估基于临床标准定义的术前血清磷异常是否与 CABG 的结果相关。
从 2001 年 1 月至 2014 年 12 月，根据术前血清磷水平，将 4989 例连续接受 CABG 的患者分为正常（2.5-4.5mg/dl；n=4544）、低磷血症（<2.5mg/dl；n=238）或高磷血症（>4.5mg/dl；n=207）组。
主要结局是中位随访 48 个月期间的全因死亡。次要结局是心血管死亡、移植物失败、心肌梗死、再次血运重建和卒中。在多变量 Cox 分析中，术前低磷血症与全因死亡显著相关（危险比[HR]1.76；95%置信区间[CI]1.13-2.76；P=0.01）。然而，这种关联取决于慢性肾脏病和急诊手术（交互 P 值分别为 0.05 和 0.03）。此外，在 IPW 调整后分析表明，术前血清磷异常与全因死亡（P=0.08）或除移植物失败以外的任何次要结局均无显著相关性。移植物失败与术前低磷血症显著相关（HR 2.51；95%CI 1.37-4.61；P=0.003）。
我们的研究表明，临床标准中的术前血清磷异常与 CABG 后的结局无关，除移植物失败外。而且，低磷血症与移植物失败的相关性仍有待评估。
