Causal relationship between hypoalbuminemia and acute kidney injury

Table 2 Included studies on cardiac surgery and acute coronary interventions

Ref.	Population/setting	Study design	Overall study size	Albumin measurement	Hypoalbuminemia-related outcomes
					AKI/ARF	Mortality
Lee et al[13]	OPCAB surgery	Prospective RCT	220	Postoperative albumin 3.5-3.9 vs < 3.0 g/dL	Increased rate: 29.5% vs 41.7%. AKI rate lower with albumin vs control (13.7% vs 25.7%; P = 0.048)	ND
Grodin et al[20]	Acute heart failure	Prospective, observational	456	Admission albumin level (continuous and stratified by median ≥ 3.5 g/dL)	NS	NS
Moguel-González et al[16]	Cardiac surgery	Prospective, observational, longitudinal	164	Preoperative albumin < 4.0 g/dL	Increased risk: OR = 3.852 (95%CI: 1.101-13.473; P = 0.063)	ND
Lee et al[14]	OPCAB surgery	Retrospective, observational, propensity score matching	1182 (incl. 323 matched pairs)	Preoperative albumin < 4.0 g/dL	Increased risk: OR = 1.83 (95%CI: 1.27-2.64); P = 0.001; propensity analysis: OR = 1.62 (95%CI: 1.12-2.35); P = 0.011	ND
Murat et al[21]	ACS and PCI	Retrospective, observational	890	Albumin level at hospitalization	Low albumin (3.52 g/dL vs 3.94 g/dL) predictive of CI-AKI: OR = 0.177 (95%CI: 0.080-0.392; P < 0.001)	ND
Kim et al[17]	Thoracic aorta repair with CPB	Retrospective, observational, propensity score matching	702 (incl. 183 matched pairs)	Preoperative albumin < 4.0 g/dL	Increased risk: OR = 2.50 (95%CI: 1.39-4.50; P = 0.002)	ND
Findik et al[15]	CAB surgery	Retrospective, observational	530	Preoperative albumin < 3.5 g/dL	Increased rate: OR = 1.661 (95%CI: 1.037-2.661); P = 0.035	ND
Go et al[19]	LVAD implantation	Retrospective, observational	200	< 2.5 g/dL (low) vs 2.5-3.5 g/dL (mid-range) vs > 3.5 g/dL (normal)	Increased ARF: 42.9% vs 16.5% vs 17.3%; P = 0.05	NS

ACS: Acute coronary syndromes; AKI: Acute kidney injury; ARF: Acute renal failure; CI-AKI: Contrast-induced acute kidney injury; CPB: Cardiopulmonary bypass; LVAD: Left ventricular assist device; ND: Not disclosed; NS: Not significant; OPCAB: Off-pump coronary artery bypass; OR: Odds ratio; PCS: Percutaneous coronary intervention; RCT: Randomized, controlled trial.