IJCS | Volume 31, Nº3, May/ June 2018

298 Martucheli et al. Cystatin C and acute coronary syndromes International Journal of Cardiovascular Sciences. 2018;31(3)290-307 Review Article Table 2 - Classification of patients, variables included in the multivariate analysis and results of the selected studies Author/ Year Classification of patients according to cystatin C levels Variables included in the multivariate analysis Results Studies included in the systematic review and meta-analysis Tonkin et al., 2015 15 1 st quartile (< 0.72 mg/L) 2 nd quartile (0.72-0.81 mg/L) 3 rd quartile (0.81-0.93 mg/L) 4 th quartile (> 0.93 mg/L) Age; sex; DM; current smoking; total cholesterol; triglycerides; fasting glycemia; acute coronary syndrome; hospitalization for unstable angina; History of coronary revascularization; systolic arterial pressure, history of hypertension; atrial fibrillation; GFR; BMI; level of dyspnea; level of angina; white blood cell count; peripheral arterial disease; use of aspirin; history of stroke. Risk of cardiovascular events or death Univariate analysis: 2 nd quartile x 1 st quartile: OR = 1.30 (1.07-1.59) 3 rd quartile x 1 st quartile: OR = 1.33 (1.08-1.63) 4 th quartile x 1 st quartile: OR = 1.75 (1.41-2.18). p < 0.001 Multivariate analysis: 2 nd quartile x 1 st quartile: OR = 1.27 (1.05-1.54) 3 rd quartile x 1 st quartile: OR = 1.31 (1.08-1.58) 4 th quartile x 1 st quartile: OR = 1.64 (1.36-1.99). p < 0.001 Akerblom et al., 2012 16 1 st quartile (< 0.68 mg/L) 2 nd quartile (0.68-0.83 mg/L) 3 rd quartile (0.83-1.01 mg/L) 4 th quartile (≥1.01 mg/L) Age; female sex; weight; smoking; hypertension; DM; MI; CHF; non- hemorrhagic stroke; peripheral artery disease; CKD; acute coronary syndrome without ST segment elevation; acute coronary syndrome with ST segment elevation; use of aspirin; use of glycoprotein IIb/IIIa inhibitors; use of beta-blockers, use of ACE inhibitor, angiotensin receptor blockers, or both; use of statin; use of proton-pump inhibitors; coronary angiography; primary PCI for acute coronary syndrome with ST segment elevation; other PCIs before index event; myocardial revascularization; serum creatinine Risk of cardiovascular events or cardiovascular death: Multivariate analysis of STEMI patients: 2 nd quartile x 1 st quartile: OR = 1.10 (0.86-1.42) 3 rd quartile x 1 st quartile: OR = 1.23 (0.96-1.58) 4 th quartile x 1 st quartile: OR = 1.81 (1.43-2.29) Multivariate analysis of NSTEMI patients: 2 nd quartile x 1 st quartile: OR = 0.94 (0.74-1.18) 3 rd quartile x 1 st quartile: OR = 1.19 (0.96-1.47) 4 th quartile x 1 st quartile: OR = 1.55(1.26-1.90) Studies included in the systematic review Tang et al., 2015 17 Cystatin C < median (< 1.36 mg/L) Cystatin C ≥ median (≥ 1.36 mg/L) Angiography without reflux; ST segment resolution < 30%; IMR > 33.7 U after PCI; serum cystatin C ≥ median; peak CK-MB; baseline LVEF; left ventricular remodeling. Proportion of patients who developed cardiovascular events or cardiovascular death: 18.5% (cystatin C ≥ median) x 13.0% (cystatin C < median). p = 0.43 Proportion of patients who developed CHF: 18.5% (cystatin C ≥ median) x 5.6% (cystatin C < median). p = 0.022 Risk for CHF: Univariate analysis: cystatin C ≥ median x cystatin C < median: OR = 4.54 (3.51 – 7.82). p < 0.001 Multivariate analysis: cystatin C ≥ median x cystatin C < median: OR = 3.85 (2.82 – 5.96). p = 0.005