Clinically-defined preoperative serum phosphorus abnormalities and outcomes of coronary artery bypass grafting: Retrospective analysis using inverse probability weighting adjustment

Autoři: Jungchan Park aff001;  Kwan Young Hong aff001;  Jeong Jin Min aff001;  Eunjin Kwon aff001;  Young Tak Lee aff002;  Wook Sung Kim aff002;  Hye Seung Kim aff003;  Kyunga Kim aff003;  Jong-Hwan Lee aff001
Působiště autorů: Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sung Kyunkwan University School of Medicine, Seoul, Korea aff001;  Department of Thoracic and Cardiovascular Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea aff002;  Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Korea aff003;  Department of Digital Health, SAIHST, Sungkyunkwan University, Seoul, Korea aff004
Vyšlo v časopise: PLoS ONE 14(12)
Kategorie: Research Article
doi: 10.1371/journal.pone.0225720



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.

Klíčová slova:

Arteries – Calcification – Coronary arteries – Coronary artery bypass grafting – Coronary heart disease – Ejection fraction – Chronic kidney disease – Myocardial infarction


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2019 Číslo 12