Table 2.

Subgroup analysis for the association between AKI and CHF

Stratification	Number of Studies	Settinga	Relative Risk	95% CI	I2, %	P Value
CHF – setting
CIN	2	-	1.69	1.44 to 1.99	0	0.43
Peri-operative	6	-	1.57	1.23 to 2.01	83
Other	2	-	1.46	1.25 to 1.70	0
CHF – recovery
Complete recovery	3	CIN (1)	1.41	1.22 to 1.62	0	0.21
		Peri-op (1)
		Other (1)
Partial or no recovery	3	CIN (1)	1.65	1.35 to 2.03	0
		Peri-op (1)
		Other (1)
CHF – severity
Mild AKI	6	CIN (2)	1.34	1.11 to 1.61	61	0.01
		Peri-op (2)
		Other (2)
Moderate to severe AKI	6	CIN (2)	1.94	1.62 to 2.31	49
		Peri-op (2)
		Other (2)
CHF – severity (adjusted for LVEF)
Mild AKI	3	CIN (2)	1.57	1.37 to 1.79	0	0.032
		Peri-op (1)
		Other (0)
Moderate to severe AKI	3	CIN (2)	1.93	1.69 to 2.20	0
		Peri-op (1)
		Other (0)
CHF – median proportion baseline CHF (min–max)
0.02 (0–0.06)	5	CIN (0)	1.56	1.35 to 1.80	44	0.91
		Peri-op (2)
		Other (3)
1 (0.15–1)	5	CIN (2)	1.58	1.38 to 1.80	0
		Peri-op (0)
		Other (3)
CHF – median proportion baseline IHD (min–max)
0.25 (0.07–0.42)	5	CIN (0)	1.43	1.27 to 1.61	0	0.020
		Peri-op (1)
		Other (4)
1 (0.72–1)	5	CIN (2)	1.71	1.56 to 1.87	0
		Peri-op (1)
		Other (2)
CHF – median proportion baseline stroke (min–max)
0.05 (0–0.06)	3	CIN (0)	1.55	1.25 to 1.92	68	0.83
		Peri-op (2)
		Other (1)
0.09 (0.07–0.09)	3	CIN (1)	1.60	1.35 to 1.88	0
		Peri-op (0)
		Other (2)
CHF – median proportion baseline CKD (min–max)
0.09 (0.07–0.17)	3	CIN (1)	1.54	1.32 to 1.79	30	0.80
		Peri-op (1)
		Other (1)
0.28 (0.24–0.33)	2	CIN (1)	1.59	1.32 to 1.91	0
		Peri-op (0)
		Other (1)

CIN, contrast induced nephropathy; Peri-op, peri-operative or intensive care unit; LVEF, left ventricular ejection fraction.

^aNumber of studies is provided in brackets.