Serum osmolarity as a potential predictor for contrast-induced nephropathy following elective coronary angiography

Int Urol Nephrol. 2020 Mar;52(3):541-547. doi: 10.1007/s11255-020-02391-4. Epub 2020 Feb 1.

Abstract

Background and objectives: Contrast-induced nephropathy (CIN) is a relatively common complication following primary coronary angiography (CAG) or percutaneous coronary intervention (PCI), especially in at-risk patients. The goal of this study is to evaluate the role of pre-procedural serum osmolarity as a risk factor for CIN in patients undergoing elective CAG for stable coronary artery disease (CAD).

Materials and methods: A total of 356 stable CAD patients scheduled to undergo CAG or PCI were included in this two-center study. Serum osmolarity was calculated on admission. CIN was defined according to the KDIGO criteria.

Results: There were 45 (12.6%) patients who developed CIN 48-72 h after CAG or PCI. CIN patients had a higher prevalence of diabetes (51.1% in those with CIN vs 24.4% in those without CIN, p < 0.001), higher serum glucose (129 mg/dL in those with CIN vs 108 mg/dL in those without CIN, p < 0.001), blood urea nitrogen (22.4 mg/dL in those with CIN vs 19.0 mg/dL in those without CIN, p = 0.01) and serum osmolarity (294.2 mOsm in those with CIN vs 290.1 mOsm in those without CIN, p < 0.001) levels, had received a higher dose of contrast (250 mL in those with CIN vs 200 mL in those without CIN, p = 0.03) but had lower hemoglobin (12.9 g/dL in those with CIN vs 13.6 g/dL in those without CIN, p = 0.04) level. In multivariate analysis, serum osmolarity [odds ratio (OR) 1.11; 95% confidence interval (CI) 1.04-1.18 for each mOsm/L increase; p = 0.001], diabetes (OR 2.43, 95% CI 1.26-4.71; p = 0.01), C-reactive protein (OR 1.04, 95% CI 1.01-1.08 for each mg/dL increase; p = 0.02) and contrast volume (OR 34.66, 95% CI 1.25-962.22 for each L increase; p = 0.04) remained as independent predictors of CIN. Serum sodium, glucose and blood urea nitrogen contributed to the excess serum osmolarity of CIN patients.

Conclusion: Serum osmolarity is a cheap and widely available marker that can reliably predict CIN after CAG or PCI. Future research should focus on determining a clinically optimal cutoff for serum osmolarity that would warrant preventive interventions. Furthermore, later research may investigate the role of serum osmolarity not only as a risk factor but also as a pathogenetic mechanism underlying CIN.

Keywords: Acute kidney injury; Contrast nephropathy; Coronary angiography; Osmolarity.

MeSH terms

  • Contrast Media / administration & dosage
  • Contrast Media / adverse effects*
  • Coronary Angiography / adverse effects*
  • Coronary Angiography / methods
  • Coronary Artery Disease / diagnosis
  • Female
  • Hematologic Tests / methods*
  • Humans
  • Kidney Diseases* / blood
  • Kidney Diseases* / chemically induced
  • Kidney Diseases* / diagnosis
  • Male
  • Middle Aged
  • Osmolar Concentration*
  • Percutaneous Coronary Intervention / adverse effects*
  • Percutaneous Coronary Intervention / methods
  • Prognosis
  • Risk Assessment / methods
  • Risk Factors

Substances

  • Contrast Media