Baseline characteristics
Baseline characteristics of the 99 patients have been previously reported (17) and are summarized in Table 1. Patients were predominantly male (n=80, 81%) with a median age of 55 [49.0–62.0] years. Patients were randomized to anakinra standard dose daily (n=33, [33%]), anakinra high dose (n=31, [31%]), or placebo (n=35, [35%]). Clinical characteristics were well matched, without statistically significant differences between anakinra and placebo groups except for a higher prevalence of diabetes mellitus in the placebo compared to anakinra group (15 [43%] vs 15 [23%], p=0.044). There were no differences between the two groups in time from symptom onset to percutaneous coronary intervention, time from symptom onset to investigational drug administration, or periprocedural drugs received. There was no difference in infarct size between the two groups, while the under the curve for high sensitivity C-Reactive Protein (CRP) was significantly lower in patients receiving anakinra versus placebo (67 [39–120] vs 214 [131–394] mg·day/L, p<0.001) (Table 2).
Table 1
Clinical characteristics of the patients in anakinra and placebo groups.
|
Anakinra
(n=64)
|
Placebo
(n=35)
|
P-value
|
Age, y
|
55 [48-61]
|
56 [51-65]
|
0.174
|
Female sex
|
14 (22)
|
5 (4)
|
0.359
|
White
|
36 (56)
|
21 (60)
|
0.223
|
Black
|
21 (33)
|
6 (17)
|
|
Hispanic
|
2 (3)
|
3 (9)
|
|
Other
|
5 (8)
|
5 (14)
|
|
Procedural characteristics
|
|
|
|
Symptom onset to PCI, min
|
187 [106-333]
|
180 [130-347]
|
0.801
|
Symptom onset to investigational drug administration, min
|
508 [348-718]
|
529 [403-716]
|
0.669
|
Fibrinolytic use before PCI
|
5 (8)
|
3 (9)
|
0.587
|
PCI type
|
|
|
|
Primary PCI
|
59 (92)
|
32 (91)
|
0.587
|
PCI after fibrinolysis
|
5 (8)
|
3 (9)
|
0.587
|
Use of drug-eluting-stent
|
44 (69)
|
30 (86)
|
0.063
|
Use of thrombectomy
|
10 (16)
|
6 (17)
|
0.844
|
Use of P2Y12 inhibitor
|
64 (100)
|
35 (100)
|
1
|
Clopidogrel
|
9 (14)
|
7 (20)
|
|
Prasugrel
|
22 (34)
|
12 (34)
|
|
Ticagrelor
|
33 (52)
|
15 (46)
|
|
Clinical characteristics
|
|
|
|
Coronary artery disease
|
14 (22)
|
7 (20)
|
0.827
|
Diabetes mellitus
|
15 (23)
|
15 (43)
|
0.044
|
Systemic arterial hypertension
|
33 (52)
|
23 (66)
|
0.174
|
Baseline LVEF, %
|
51 [44-58]
|
53 [42-57]
|
0.963
|
Abbreviations: STEMI: ST elevation myocardial infarction; PCI: percutaneous coronary intervention; Min: minutes; LVEF: left ventricle ejection fraction. |
Table 2
Laboratory data according to anakinra and placebo.
|
Anakinra
(n=64)
|
Placebo
(n=35)
|
P-value
|
CKMB-AUC, ng/mL*d
|
2219 [1130-3821]
|
2351 [765-4668]
|
0.859
|
At admission
|
|
|
|
Hemoglobin, g/dL
|
14.5 [13.4-15.3]
|
14.4 [13.6-15.6]
|
0.692
|
Hematocrit, %
|
43 [40-47]
|
42 [41-44]
|
0.558
|
White blood cell, 109/L
|
10.85 [8.52-13.90]
|
11.40 [9.20-15.07]
|
0.692
|
Absolute neutrophil count, 109/L
|
7.45 [4.72-11.05]
|
7.30 [5.20-12.50]
|
0.622
|
Absolute lymphocyte count, 109/L
|
2.05 [1.3-3.02]
|
1.8 [1.30-2.55]
|
0.699
|
Absolute monocyte count, 109/L
|
0.60 [0.40-0.80]
|
0.70 [.50-0.80]
|
0.185
|
Absolute eosinophil count, 109/L
|
0.10 [0.00-0.125]
|
0.10 [0.00-0.20]
|
0.279
|
Neutrophil to lymphocyte ratio
|
4.29 [1.99-7.51]
|
3.71 [2.08-8.37]
|
0.719
|
Creatinine, mg/dL
|
0.94 [0.78-1.10]
|
1.00 [0.89-1.34]
|
0.063
|
NTproBNP, pg/mL
|
52.50 [22.00-217.59]
|
95.5 [23.75-244.00]
|
0.614
|
At 72 hours
|
|
|
|
White blood cell, 109/L
|
7.50 [6.20-8.35]
|
8.30 [7.20-9.80]
|
|
% Change from baseline
|
-35% [-48 to -24]
|
-21% [-34 to -10]
|
0.008
|
Absolute neutrophil count, 109/L
|
4.15 [3.22-5.07]
|
5.40 [4.65-5.40]
|
|
% Change from baseline
|
-48% [-60 to -22]
|
-27% [-46 to -5]
|
0.004
|
Absolute lymphocyte count, 109/L
|
2.15 [1.50-2.60]
|
1.80 [1.40-2.20]
|
|
% Change from baseline
|
-7% [-4% to +32]
|
-6% [-38 to +22]
|
0.657
|
Absolute monocyte count, 109/L
|
0.60 [0.50-0.80]
|
0.80 [0.60-0.95]
|
|
% Change from baseline
|
+11% [-29 to +51]
|
+14% [-13 to + 47]
|
0.604
|
Absolute eosinophil count, 109/L
|
0.20 [0.10-0.30]
|
0.10 [0.10-0.30]
|
|
% Change from baseline
|
+50% [0 to +100]
|
0% [-50 to +62]
|
0.022
|
Neutrophil to lymphocyte ratio
|
1.90 [1.37-3.22]
|
3.35 [2.6
|
|
% Change from baseline
|
-54% [-13 to +70]
|
-13% [-58 to +70]
|
0.047
|
At 14 days
|
|
|
|
White blood cell, 109/L
|
7.10 [5.70-9.40]
|
8.60 [6.92-10.5]
|
|
% Change from baseline
|
-33% [-45 to – 22]
|
-20% [-41 to -9]
|
0.044
|
Absolute neutrophil count, 109/L
|
4.60 [3.30-5.50]
|
5.50 [4.00-7.15]
|
|
% Change from baseline
|
-42% [-61 to -25]
|
-32% [-51% to -1]
|
0.067
|
Absolute lymphocyte count, 109/L
|
2.10 [1.50-2.60]
|
2.00 [1.70-2.27]
|
|
% Change from baseline
|
0% [-32 to +32]
|
+10% [-22 to 40]
|
0.313
|
Absolute monocyte count, 109/L
|
0.60 [0.50-0.80]
|
0.65 [0.50-0.70]
|
|
% Change from baseline
|
-5% [-30 to + 26]
|
0% [-20 to + 3]
|
0.989
|
Absolute eosinophil count, 109/L
|
0.20 [0.10-0.30]
|
0.20 [0.20-0.30]
|
|
% Change from baseline
|
+100% [0 to + 200]
|
0% [-30 to +100]
|
0.043
|
Neutrophil to lymphocyte ratio
|
2.26 [1.34-3.25]
|
2.89 [1.93-3.68]
|
|
% Change from baseline
|
-50% [-67 to 10]
|
-36% [-65 to +3]
|
0.500
|
At 3 months
|
|
|
|
White blood cell, 109/L
|
6.90 [5.90-8.60]
|
7.55 [6.05-9.47]
|
|
% Change from baseline
|
-41% [-49 to -16]
|
-30% [-44 to -19]
|
0.301
|
Absolute neutrophil count, 109/L
|
4.20 [3.30-5.20]
|
4.35 [3.50-5.70]
|
|
% Change from baseline
|
-53% [-61 to -25]
|
- 43% [-54 to -33]
|
0.298
|
Absolute lymphocyte count, 109/L
|
2.10 [1.50-2.60]
|
2.00 [1.57-2.30]
|
|
% Change from baseline
|
-3% [-29 to + 35]
|
+8% [-28 to + 59]
|
0.584
|
Absolute monocyte count, 109/L
|
0.60 [0.50-0.70]
|
0.65 [0.50-0.70]
|
|
% Change from baseline
|
-10% [-28 to + 24]
|
7% [-30 to + 25]
|
0.748
|
Absolute eosinophil count, 109/L
|
0.20 [0.10-0.20]
|
0.20 [0.10-0.32]
|
|
% Change from baseline
|
0% [0 to 100]
|
+33% [o to 100%]
|
0.764
|
Neutrophil to lymphocyte ratio
|
2.09 [1.35-2.85]
|
2.61 [1.73-3.24]
|
|
% Change from baseline
|
-51% [-70 to 17]
|
- 42% [-75 to -9]
|
0.964
|
Data are expressed as median [interquartile range]. P-values in bold character indicate significant values (<0.05) for difference between groups. Abbreviations: CKMB-AUC: Creatine kinase-MB area under the curve; CRP-AUC: C-reactive protein area under the curve; NTproBNP: N-terminal pro-brain natriuretic peptide.
|
White Blood Cell Count and Differential Count during STEMI
Table 2 shows WBC count with differential and other laboratory parameters in the two groups. There were no significant differences in any of the laboratory parameters at baseline. A significant reduction in WBC (11.40 [9.20-15.07] vs 8.30 [7.20-9.80] 109/L; -21% [-34 to -10], P<0.001 within placebo group) and neutrophil count (7.30 [5.20-12.50] vs 5.40 [4.65-5.40] 109/L; -27% [-46 to -5], P=0.003 within placebo group) were seen in the placebo group at 72 hours (Table 2).
Effect of Treatment with Anakinra on White Blood Count
At 72 hours, when compared with placebo, treatment with anakinra led to a statistically significant greater percentage reduction in total WBC count (-35% [-48 to -24] vs -21% [-34 to -10], P<0.001 within anakinra group, and P=0.008 for between groups differences) (Figure 1, Table 2). A significantly greater percentage reduction in WBC count persisted in the anakinra group compared to placebo group at 14 days, while on treatment, and it was no longer seen at 90 days following discontinuation of treatment (Figure 1, Table 2).
Effect of Treatment with Anakinra on Leukocyte Differential Count
At 72 hours, when compared with placebo, treatment with anakinra led to a statistically significant greater percentage reduction in absolute neutrophil count (-48% [-60 to -22] vs -27% [-46 to -5], P<0.001 within anakinra group, and P=0.004 for between groups differences), and neutrophil to lymphocyte ratio (-54% [-13 to +70] vs -13% [-58 to +70], P<0.001 within anakinra group, and P=0.047 for between groups differences), and to an increase in absolute eosinophil count (+50% [0 to +100] vs 0% [-50 to +62], P<0.001 within anakinra group, and P=0.022 for between groups differences)(Figure 1, Table 2). A significantly greater percentage increase in absolute eosinophil count persisted in the anakinra group compared to placebo group at 14 days, while on treatment, and it was no longer seen at 90 days following discontinuation of treatment (Figure 1, Table 2).