Redox status of patients before cardiac surgery

Figures & data

Table 1. Number of cases, range, mean, standard deviation, and reference values for all numeric parameters determined in the study. Reference values for redox parameters are discussed in the text.

Parameter	N	Range	Mean ± SD	1st Q/Median/3rd Q	Reference
TAOS [µM]	469	175–895	555 ± 107	483/550/617	see text
tGSH in whole blood [mM]	500	0.11–1.11	0.61 ± 0.19	0.48/0.62/0.76	see text
tGSH in erythrocytes [mM]	497	0.34–2.83	1.52 ± 0.48	1.18/1.56/1.86	see text
GPx [U/ml whole blood]	500	5.69–32.3	15.6 ± 4.26	12.65/15.45/18.41	see text
GPx [U/mg Hb]	497	0.04–0.22	0.11 ± 0.03	0.09/0.11/0.13	see text
NOx [µM]	484	8.79–183	35.9 ± 25.0	20.9/28.5/41.6	see text
Age [years]	497	22–89	68.6 ± 10.6	63/71/76	–
BMI	494	16.9–43.4	28.3 ± 4.40	25.4/28.0/30.8	18.5–24.9
WHR	495	0.78–1.20	1.00 ± 0.06	0.97/1.02/1.04	< 0.85 (w); <1.0 (m)
C-peptide [ng/ml]	493	0.49–21.1	2.46 ± 1.55	1.61/2.16/2.88	0.9–4.0
HDL [mg/dl]	495	13–104	42.3 ± 12.4	34/40/49	40–80
LDL [mg/dl]	496	10–242	104 ± 36.3	78/100/127	65–150
Triglycerides [mg/dl]	497	43–858	148 ± 95.4	94/127/169	50–245
CRP [mg/l]	496	0.50–296	8.97 ± 19.8	0.78/2.9/8.70	< 1
Creatinine [mg/dl]	497	0.4–6.9	1.04 ± 0.56	0.8/0.9/1.1	0.6–1.3
Leucocytes [giga/l]	496	2.2–19.6	7.6 ± 2.22	6.1/7.3/8.85	3.9–10.2
ICS [days]	496	1–50	3.68 ± 4.90	2/2/4	–

Abbreviations used: BMI: body mass index; CRP: C-reactive protein; GPx: glutathione peroxidases; tGSH: total (reduced and oxidized) glutathione; HDL: high-density lipoprotein; ICS: intensive care stay; LDL: low-density lipoprotein; NOx: reactive nitrogen species; TAOS: total antioxidant status; WHR: waist–hip ratio.

Figure 1. Distribution of the categorical characteristics of the patients. The number of patients was 497. The figure shows for each parameter the number of positive (i.e. arterial hypertension 450) and negative (i.e. 47) cases. Abbreviations used: ACE: angiotensin-converting enzyme; CAD: coronary artery disease; CCB: calcium channel blocker; COPD: chronic obstructive pulmonary disease; MI: myocardial infarction; PH: pulmonary hypertension.

Figure 2. Box-whisker plots of the four redox parameters. Abbreviations used: GPx: glutathione peroxidases [U/ml]; NOx: nitrate/nitrite [µM]; TAOS: total antioxidant status [mM]; tGSH: total (reduced and oxidized) glutathione [µM].

Figure 3. Principal component analysis (PCA) of all parameters. Redox parameters are shown in red. Abbreviations used: ACE: angiotensin-converting enzyme; ARB: angiotensin receptor blocker; BMI: body mass index; CCB: calcium channel blocker; COPD: chronic obstructive pulmonary disease; CRP: C-reactive protein; GPx: glutathione peroxidases; HDL: high-density lipoprotein; ICS: intensive care stay; LDL: low-density lipoprotein; MI: myocardial infarction; NOx: nitrate/nitrite; PH: pulmonary hypertension; TAOS: total antioxidant status; tGSH: total glutathione; WHR: waist–hip ratio.

Figure 4. Pearson correlations of redox and metabolic parameters. Color saturation indicates the strength of the correlation. Abbreviations used: BMI: body mass index; CRP: C-reactive protein; GPx: glutathione peroxidases; HDL: high-density lipoprotein; ICS: intensive care stay; LDL: low-density lipoprotein; MI: myocardial infarction; NOx: nitrate/nitrite; PH: pulmonary hypertension; TAOS: total antioxidant status; TG: triglycerides; tGSH: total glutathione; WHR: waist–hip ratio.

Figure 5. Cluster analyses of the correlations. Abbreviations used: BMI: body mass index; CRP: C-reactive protein; GPx: glutathione peroxidases; HDL: high-density lipoprotein; ICS: intensive care stay; LDL: low-density lipoprotein; NOx: nitrate/nitrite; TAOS: total antioxidant status; tGSH: total glutathione; WHR: waist–hip ratio.

Table 2. Overview of all model variables and their significance.

TAOS	tGSH	GPx	NOx
Log2(creatinine)*** ↑	Log2(C-peptide)** ↑	Smoking** ↓	Log2(creatinine)*** ↑
Log2(TG)*** ↑	COPD:CCB* ↓	Log2(TG)* ↑	Gender Female*** ↑
PH*** ↑	CCB* ↑	LDL^#	ACE inhibitors*** ↓
COPD:CCB** ↑	Log2(TG)* ↓	PH^# ↑	ACEinh:Log2(HDL)*** ↑
Ventr. arrhyth.* ↑	Ventr. arrhyth.^# ↑		Ventr. arrhyth.*** ↑
			Diabetes** ↑
			Log2(CRP)** ↑
			Log2(HDL)** ↓
		PH* ↑
		LDL^#
		COPD:CCB ^# ↑
		COPD^# ↑
		CCB^# ↓
		Smoking^# ↓
		Log2(TG)^# ↑

Abbreviations used are. ACE: angiotensin-converting enzyme; CCB: calcium channel blocker; COPD: chronic obstructive pulmonary disease; CRP: C-reactive protein; GPx: glutathione peroxidases; HDL: high-density lipoprotein; LDL: low-density lipoprotein; NOx: reactive nitrogen species; PH: pulmonary hypertension; TAOS: total antioxidant status; TG: triglycerides; tGSH: total (reduced and oxidized) glutathione. Variables connected with a colon indicate statistical interaction of the variables.

The predictors are arranged according to their significance levels in the linear models. *** = highly significant (0 < p < 0.001), ** = very significant (0.001 < p < 0.01), and * = significant (0.01 < p < 0.05). P-values between 0.05 and 0.1 are marked with #. ↑ and ↓ indicate whether the predictor increases or decreases the redox parameter. Smoking, for instance, decreases GPx activity, while triglycerides increase it.