Association of Different Lactate Indices with 30-Day and 180-Day Mortality in Patients with ST-Segment Elevation Myocardial Infarction Treated with Primary Percutaneous Coronary Intervention: A Retrospective Cohort Study

Figures & data

Table 1 Characteristics of Study Patients

Characteristics	All Patients	Survivors	Non-Survivors	P
N	1080	1012	68
Lactate series index
Lacadm	2.3 (1.6–3.3)	2.3 (1.6–3.2)	4.4 (2.4–7.8)	<0.001
Lac24max	2.8 (2.1–3.8)	2.7 (2.1–3.6)	5.7 (3.3–12.0)	<0.001
Lac24min	1.8 (1.4–2.3)	1.7 (1.4–2.2)	2.5 (1.8–4.4)	<0.001
Lac24tw	2.3 (1.8–3.0)	2.2 (1.8–2.8)	3.9 (2.4–6.2)	<0.001
LacΔ	−0.2 (−0.9–0.4)	−0.2 (−0.9–0.3)	−0.2 (−1.7–1.1)	0.963
Survival outcome
30-Day Death	59 (5.5%)	0 (0.0%)	59 (86.8%)	<0.001
180-Day Death	68 (6.3%)	0 (0.0%)	68 (100%)	<0.001
GRACE score	163.4 ± 38.0	159.2 ± 34.0	226.2 ± 38.9	<0.001
Demographics
Age (years)	64.4 ± 13.0	63.8 ± 13.0	73.8 ± 9.9	<0.001
Male	850 (78.7%)	813 (80.3%)	37 (54.4%)	<0.001
Medical history
Hypertension	631 (58.4%)	584 (57.7%)	47 (69.1%)	0.065
Diabetes Mellitus	245 (22.7%)	223 (22.0%)	22 (32.4%)	0.049
Current Smoking	534 (49.4%)	517 (51.1%)	17 (25.0%)	<0.001
Current Drinking	263 (24.4%)	251 (24.8%)	12 (17.6%)	0.183
Previous MI	26 (2.4%)	25 (2.5%)	1 (1.5%)	0.603
Previous PCI	51 (4.7%)	47 (4.6%)	4 (5.9%)	0.641
Previous CABG	2 (0.2%)	1 (0.1%)	1 (1.5%)	0.011
Previous Stroke	63 (5.8%)	59 (5.8%)	4 (5.9%)	0.986
Presentation characteristics
SBP (mmHg)	123.5 ± 22.3	124.3 ± 22.0	111.7 ± 23.0	<0.001
DBP (mmHg)	74.9 ± 14.9	75.3 ± 14.9	68.5 ± 14.3	<0.001
HR (beats/min)	82.1 ± 18.5	81.1 ± 17.7	97.4 ± 21.8	<0.001
Killip class II–IV	258 (23.9%)	206 (20.4%)	52 (76.5%)	<0.001
Laboratory tests
AST (U/l)	250.0 (126.0–410.0)	240.5 (122.0–392.2)	369.5 (233.0–686.5)	<0.001
BNP (ng/l)	117.0 (44.8–318.8)	110.0 (40.8–288.5)	368.0 (123.2–1243.2)	<0.001
Hs-cTnI (ng/l)	43.0 (12.1–50.0)	41.1 (11.5–50.0)	50.0 (37.4–50.0)	0.011
Creatinine (mmol/l)	68.0 (57.0–85.2)	67.0 (56.0–83.0)	108.0 (75.8–160.2)	<0.001
Hemoglobin (g/l)	131.5 (119.0–143.0)	240.5 (122.0–392.2)	369.5 (233.0–686.5)	<0.001

Notes: Continuous variables are presented as mean (SD) for normally distributed variables or median (interquartile range) for non-normally distributed variables, whereas categorical variables are presented as number (percentage).

Abbreviations: Lac_adm, lactate at admission; Lac_24max, maximal lactate during 24h after admission; Lac_24min, minimum lactate during 24h after admission; Lac_24tw, time-weighted lactate during 24h after admission; Lac_Δ, lactate at 24h after admission minus lactate at admission; MI, myocardial infarction; PCI, percutaneous coronary intervention; CABG, coronary artery bypass grafting; SBP, systolic blood pressure; DBP, diastolic blood pressure; HR, heart rate; AST, aspartate aminotransferase; BNP, brain natriuretic peptide; Hs-cTnI, high-sensitivity troponin I.

Table 2 Association of Lactate Series with the All-Cause Mortality

Variables	Model 1		Model 2		Model 3
	Hazard Ratio (95% CI)	P value	Hazard Ratio (95% CI)	P value	Hazard Ratio (95% CI)	P value
30-day mortality
Lacadm, mmol/L	1.43 (1.34, 1.52)	<0.001	1.40 (1.30, 1.49)	<0.001	1.16 (1.05, 1.29)	0.005
Lac24max, mmol/L	1.54 (1.44, 1.64)	<0.001	1.50 (1.40, 1.60)	<0.001	1.34 (1.21, 1.48)	<0.001
Lac24min, mmol/L	1.83 (1.66, 2.01)	<0.001	1.73 (1.57, 1.91)	<0.001	1.46 (1.27, 1.69)	<0.001
Lac24tw, mmol/L	1.83 (1.67, 1.99)	<0.001	1.72 (1.57, 1.88)	<0.001	1.47 (1.30, 1.67)	<0.001
LacΔ, mmol/L	1.07 (0.89, 1.29)	0.460	1.06 (0.89, 1.25)	0.530	1.20 (1.08, 1.34)	<0.001
180-day mortality
Lacadm, mmol/L	1.42 (1.33, 1.51)	<0.001	1.39 (1.30, 1.48)	<0.001	1.15 (1.04, 1.26)	0.005
Lac24max, mmol/L	1.52 (1.43, 1.62)	<0.001	1.48 (1.39, 1.58)	<0.001	1.30 (1.18, 1.43)	<0.001
Lac24min, mmol/L	1.83 (1.67, 2.01)	<0.001	1.73 (1.57, 1.91)	<0.001	1.48 (1.30, 1.69)	<0.001
Lac24tw, mmol/L	1.82 (1.67, 1.98)	<0.001	1.70 (1.56, 1.85)	<0.001	1.46 (1.30, 1.64)	<0.001
LacΔ, mmol/L	1.01 (0.86, 1.18)	0.910	1.00 (0.86, 1.16)	0.986	1.20 (1.08, 1.33)	<0.001

Notes: Model 1 adjust for: None. Model 2 adjust for: gender and age. Model 3 adjust for: gender; age; current smoking; current drinking; hypertension; diabetes mellitus; prior stroke; prior myocardial infarction; prior CABG; creatinine; hemoglobin; systolic blood pressure; heart rate and Killip class at admission 2–4.

Abbreviations: PCI, prior percutaneous coronary intervention; AST, aspartate aminotransferase; BNP, brain natriuretic peptide; Hs-cTnI, high-sensitivity troponin I.

Figure 1 Kaplan–Meier survival curves of all-cause mortality according to lactate indices. Panels (A–E) Indicate Lacadm, Lac24max, Lac24min, Lac24TW and LacΔ, respectively.

Notes: The red line, the low lactate indices; the green line, the middle lactate indices; the blue line, the high lactate indices.

Table 3 The Area Under ROC Curve (AUC) for Lactate Indices

Variables	30-Day Death		180-Day Death
	AUC (95% CI)	P-value*	AUC (95% CI)	P-value*
Lacadm	0.757 (0.731–0.783)		0.751 (0.724–0.777)
Lac24max	0.812 (0.787–0.835)	0.0070	0.803 (0.778–0.826)	0.0060
Lac24min	0.742 (0.715–0.768)	0.5729	0.725 (0.697–0.752)	0.3535
Lac24tw	0.786 (0.760–0.810)	0.2057	0.775 (0.749–0.800)	0.2344
LacΔ	0.554 (0.523–0.584)	0.0041	0.518 (0.487–0.548)	0.0004

Note: *Compared to Lac_adm.

Figure 2 Receiver operating characteristic (ROC) analysis for lactate indices. Panel (A) is the 30-day mortality rate, and Panel (B) is the 180-day mortality rate.

Table 4 The Area Under ROC Curve (AUC) for GRACE Score + Lactate Index

Variables	30-Day Death		180-Day Death
	AUC (95% CI)	P-value*	AUC (95% CI)	P-value*
GRACE score	0.893 (0.873–0.911)		0.893 (0.873–0.911)
+Lacadm	0.899 (0.880–0.917)	0.0756	0.898 (0.878–0.915)	0.1450
+Lac24max	0.914 (0.896–0.930)	0.0112	0.910 (0.891–0.926)	0.0281
+Lac24min	0.906 (0.888–0.923)	0.0855	0.903 (0.884–0.920)	0.1781
+Lac24tw	0.913 (0.894–0.929)	0.0415	0.907 (0.888–0.924)	0.1098
+LacΔ	0.890 (0.870–0.908)	0.7413	0.891 (0.871–0.909)	0.7387

Note: *Compared to GRACE score.

Figure 3 Receiver operating characteristic (ROC) analysis for GRACE score +lactate indices. Panel (A) is the 30-day mortality rate, and Panel (B) is the 180-day mortality rate.