An Association Between C-Reactive Protein Levels and the Occurrence of Cognitive Dysfunction After Heart Valve Replacement

Figures & data

Table 1 Normal Laboratory Values

Laboratory Values	Normal Value
Hemoglobin, g/dL (median [IQR])	13.2–17.3
Hematocrit	32–62%
Leukocyte count, ×10^3/μL	3.8–10.6
Platelet count, ×10^3/μL	150–400
Blood glucose level, mg/dL	80–160
Blood urea nitrogen level, mg/dL	15–39
Creatinine level, mg/dL	0.6–1.30
Albumin level, g/dL	3.4–5.0
Aspartate aminotransaminase level, U/L	15–34
Alanine aminotransaminase level, U/L	15–60
Sodium level, mmol/L	136–145
Potassium level, mmol/L	3.5–5.0
Chloride, level mmol/L	95–105
Calcium level, mmol/L	2.12–2.52
Magnesium level, mmol/L	0.74–0.99
C-reactive protein level, mg/dL	0–0.30

Table 2 Demographic and Preoperative Data

Characteristics	All Patients	POCD	Non-POCD
n	32 (100%)	28 (87.5%)	4 (12.5%)
Age, years (median [IQR])	42.5 (35.2, 52.0)	44.5 (37.5, 54.2)	29.5 (40.5, 17.8)
Sex
Female	22 (68.8%)	19 (54.2%)	3 (9.3%)
Male	10 (31.2%)	9 (28.1%)	1 (3.1%)
Education background
Elementary school	7 (21.9%)	7 (100%)	0 (0%)
Junior high school	10 (31.3%)	9 (90%)	1 (10%)
Senior high school	15 (46.9%)	12 (80%)	3 (20%)
Weight, kg (median [IQR])	51.0 (46.0, 63.8)	51.5 (45.2, 66.2)	50.5 (48.5, 57.8)
Height, cm (median [IQR])	156.5 (153.2, 161.8)	156.5 (153.2, 161.8)	156.0 (153.5, 161.5)
Body mass index, kg/m^2 (median [IQR])	21.05 (19.35, 24.31)	21.40 (19.33, 24.55)	20.66 (19.52, 23.46)
History of atrial fibrillation	16 (50%)	16 (100%)	0 (0%)

Table 3 Preoperative Diagnosis and Surgical Procedure

	All Patients	POCD	Non-POCD
Mitral regurgitation	27 (100%)	23 (85.2%)	4 (14.8%)
Mitral stenosis	10 (100%)	9 (90%)	1 (10%)
Aortic regurgitation	12 (100%)	9 (75%)	3 (25%)
Aortic stenosis	5 (100%)	5 (100%)	0 (0%)
Tricuspid regurgitation	10 (100%)	8 (80%)	2 (20%)
Pulmonary regurgitation, mild	4 (12.5%)	4 (100%)	0 (0%)
Pulmonary hypertension	1 (3.1%)	1 (100%)	0 (0%)
Surgical procedure
MVR	11 (34.4%)	10 (90.9%)	1 (9.1%)
Aortic valve replacement	3 (9.4%)	2 (66.7%)	1 (33.3%)
DVR	5 (15.6%)	5 (100%)	0 (0%)
MVR + TV repair	11 (34.4%)	10 (90.9%)	1 (9.1%)
DVR + TV repair	2 (6.3%)	1 (50%)	1 (50%)
Echocardiography: LVEF (median [IQR])	64.1% (51.1%, 67.7%)	64.1% (51.1%, 67.7%)	64.2% (51.5%, 71.1%)

Abbreviations: DVR, double valve replacement; MVR, mitral valve replacement; POCD, postoperative cognitive dysfunction; TV, tricuspid valve.

Table 4 Pre and Postoperative Data in POCD

	Preoperative	Postoperative	Differences
Hemoglobin, g/dL (median [IQR])	12.85 (13.95, 12.05)	10.95 (10.40, 11.85)	−1.9 (−14.79%)
Hematocrit	38.95% (34.75%, 41.50%)	32.50% (31.55%, 35.15%)	−6.45 (−16.56%)
Leukocyte count, ×10^3/μL	7.80 (5.72, 9.05)	12.6 (10.9, 14.5)	4.80 (61.54%)
Platelet count, ×10^3/μL	257.5 (232.5, 286.8)	162 (138, 181.5)	−95.5 (−37.09%)
Blood glucose level, mg/dL	94.0 (81.2, 108.5)	172 (150.2, 197.5)	78 (82.98%)
Blood urea nitrogen level, mg/dL	31.5 (26.2, 39.2)	31.0 (26.5, 34.8)	−0.50 (−1.59%)
Creatinine level, mg/dL	1.01 (0.83, 1.15)	1.0 (0.9, 1.1)	−0.01 (−0.99%)
Albumin level, g/dL	4.3 (4.0, 4.5)	3.6 (3.15, 4.13)	−0.70 (−16.28%)
Aspartate aminotransaminase level, U/L	25 (22, 27)	36.0 (28.0, 43.8)	11.0 (44%)
Alanine aminotransaminase level, U/L	22 (14, 25)	21.5 (18.0, 28.8)	−0.50 (−2.27%)
Sodium level, mmol/L	138.5 (134.2, 142.8)	138 (135, 140)	−0.50 (−0.36%)
Potassium level, mmol/L	3.9 (3.6, 4.2)	4.2 (3.8, 5.1)	0.30 (7.69%)
Chloride, level mmol/L	101 (99, 104)	101 (98.2, 105.8)	0 (0%)
Calcium level, mmol/L	2.28 (2.18, 2.40)	2.10 (2.02, 2.24)	−0.18 (−7.89%)
Magnesium level, mmol/L	0.87 (0.79, 0.95)	0.8 (0.7, 0.9)	−0.07 (−8.05%)
C-reactive protein level, mg/dL	0.16 (0.12, 0.21)	7.18 (4.71, 8.83)	7.02 (4387.5%)
MoCA-INA score	27.5 (27.0, 29.0)	17.5 (14.0, 21.75)	10 (−36.36%)

Table 5 Intraoperative Data

Characteristics	All Patients	POCD	Non-POCD
n	32 (100%)	28 (87.5%)	4 (12.5%)
Surgery duration, minutes (median [IQR])	120 (95, 134)	120 (95, 134)	130 (108, 145)
Anesthesia duration, minutes (median [IQR])	260 (218, 289)	245 (202, 280)	292.5 (273.8, 300.0)
CPB duration, minutes (median [IQR])	40.5 (34.2, 56.8)	40.5 (34.2, 54.8)	47.0 (35.0, 70.2)
Cross-clamp duration, minutes (median [IQR])	23 (20, 47)	23 (20, 46)	30.5 (20.0, 50.8)
Patients given direct current shocks
One shock	17 (53.1%)	7 (87.5%)	1 (25%)
Two shocks	17 (53.1%)	15 (88.2%)	2 (11.8%)
Three shocks	2 (6.3%)	2 (100%)	0 (0%)
Four or more shocks	2 (6.3%)	2 (100%)	0 (0%)
Indication for direct current shock
Ventricular fibrillation	24 (75%)	22 (91.7%)	2 (8.3%)
Ventricular tachycardia	2 (6.3%)	2 (100%)	0 (0%)
Atrial fibrillation	2 (6.3%)	1 (50%)	1 (50%)
Bleeding volume, mL (median [IQR])	350 (300, 365)	350 (300, 378)	300 (300, 338)
Temperature during CPB, °C (median [IQR])	32.5 (31.5, 33.8)	32.2 (31.5, 33.5)	33.5 (31.9, 34.6)
Temperature during rewarming after CPB, °C (median [IQR])	31.75 (31.5, 32.2)	31.75 (31.42, 32.2)	31.85 (31.55, 34.32)
Nasopharynx temperature during rewarming after CPB, °C (median [IQR])	32.95 (31.52, 34.08)	32.95 (31.6, 34.0)	33.0 (31.25, 35.05)
Temperature when CPB was discontinued, °C (median [IQR])	36.1 (36.0, 36.2)	36.1 (36.1, 36.3)	36.05 (35.4, 36.18)

Abbreviations: CPB, cardiopulmonary bypass; POCD, postoperative cognitive dysfunction.

Table 6 Bivariate Analysis

Characteristics	All Patients	POCD	Non-POCD	P value	R value
n	32 (100%)	28 (87.5%)	4 (12.5%)
Elevated levels of C-reactive protein, mg/dL (median [IQR])	6.6 (4.0, 8.3)	7.05 (4.52, 8.46)	2.98 (2.28, 3.83)	0.003*	0.501

Abbreviation: POCD, postoperative cognitive dysfunction.

Figure 1 Receiver operating characteristic (ROC) curve analysis of CRP level as diagnostic tool of POCD. CRP concentration cutoff of 3.345 mg/dL was selected with 89.3% sensitivity and 75% specificity. Area under the curve (AUC) was 0.938.