Table 1.

Baseline Characteristics of the Total Cohort

Characteristic	Total Cohort (n = 401)	Metformin Treatment (n = 99)	No Metformin Treatment (n = 302)	P Value
Age, y	56 ± 11	56 ± 11	56 ± 11	.960
Male sex, %	75	79	73	.266
Left ventricular ejection fraction, %	24 ±7	24 ± 7	24 ± 7	.860
New York Heart Association III/IV, %	42/45	56/29	37/49	.016
Body mass index, kg/m2	28.1 ± 5.4	29.2 ± 6.1	27.7 ± 5.2	.027
Peak VO2, mL ·kg · min	12.3 ± 3.9	13.2 ± 3.5	11.9 ± 4.0	.030
Coronary artery disease, %	60	59	60	.813
Hypertension, %	60	59	60	.767
Smoking history, %	57	52	59	.192
Diabetes history, y (n = 223)	9.9 ± 9.0	6.1 ± 6.0	11.3 ± 9.5	.0001
Hemoglobin A1c, %	8.2 ± 2.0	8.2 ± 1.8	8.1 ± 2.1	.799
Total cholesterol, mg/dL	164 ± 61	169 ± 54	162 ± 63	.388
Creatinine, mg/dL	1.5 ± 1.0	1.2 ± 0.4	1.6 ± 1.1	.0001
Stage of chronic kidney disease*, %
0–1	7.4	12.5	5.7	.0001
2	35.4	59.4	27.3
3	44.2	20.8	52.1
4	11.1	7.3	12.4
5	1.9	0	2.5
Blood urea nitrogen, mg/dL	34 ± 22	27 ± 19	36 ± 22	.0001
Hemoglobin, g/dL	12.9 ± 1.9	13.6 ± 1.7	12.6 ± 2.0	.0001
Hemoglobin <11 g/dL, %	17.2	5.8	20.9	.001
Albumin, g/dL	3.7 ± 0.6	3.9 ± 0.5	3.6 ± 0.6	.001
Sodium, mmol/L	136 ± 5	137 ± 4	136 ± 5	.029
B-type natriuretic peptide, pg/mL (n = 191)	534 (199–1200)	489 (115–925)	693 (257–1300)	.037
QRS duration, ms	130 ± 39	123 ± 33	132 ± 40	.093
Implantable cardioverter-defibrillator placed, %	44	54	41	.017
Biventricular pacemaker placed, %	17	21	16	.141

^*Stage of chronic kidney disease is based on estimate of glomerular filtration rate (mL/min) from the Modification of Diet in Renal Disease (MDRD) equation: Stage 0–1, >90 mL/min; Stage 2, 60–89 mL/min; Stage 3, 30–59 mL/min; Stage 4, 15–29 mL/min; Stage 5, <15 mL/min.