C-reactive Protein Is a Strong Predictor of Mortality in Hemodialysis Patients

Figures & data

Figure 1 Flow of the patients through the study.

Table 1 Characteristics of 256 chronic hemodialysis patients enrolled in the study

Characteristic	Number of patients (%)
Age (mean±SD, years)	62 ± 13
Sex
Men	116 (45.3)
Women	140 (54.7)
Time on hemodialysis (mean±SD, months)	52 ± 38
CRP (median, range, mg/L)	4.4 (0.1–99.7)
Serum albumin (mean±SD, g/L)	37 ± 4
Kt/V urea (mean±SD)	1.3 ± 0.3
Vascular access type
Arteriovenous fistula	202 (78.9)
Arteriovenous synthetic graft	7 (2.7)
Central venous catheter (permanent type)	47 (18.4)
Underlying renal disease
Diabetic nephropathy	80 (31.3)
Glomerulonephritis	54 (21.1)
Vascular disease	50 (19.5)
Pyelonephritis	23 (9)
Polycystic disease	16 (6.3)
Interstitial nephritis	8 (3.1)
Other	25 (9.7)

*CRP = C-reactive protein.

Figure 2 Receiver operating characteristics (ROC) curve for C-reactive protein (CRP) as a predictor of death. Area under curve was 0.843. Data for C-reactive protein values were collected from 232 maintenance hemodialysis patients. The CRP cutoff value where the sensitivity and specificity were the highest (80% and 70%, respectively) was 6.2 mg/L.

Table 2 Causes of death in 59 chronic hemodialysis patients during two-year follow-up

Cause of death	Number of patients (%)
Cardiovascular event
Myocardial infarction	16 (27.1)
Congestive heart failure	13 (22.0)
Stroke	9 (15.3)
Infection
Sepsis	10 (16.9)
Pneumonia	4 (6.8)
Other causes
Malignant tumors	5 (8.5)
Hyperkalemia	2 (3.4)

Table 3 Distribution of cardiovascular and non-cardiovascular causes of death according to the baseline serum concentration of C-reactive protein (CRP) in 59 chronic hemodialysis patients who died during two-year follow-up

	Number of patients (%)
CRP (mg/L)	Cardiovascular cause of death (n = 38)	Non-cardiovascular cause of death (n = 21)
<3.0 (n = 8)	3 (37.5)	5 (62.5)
3.0–6.1 (n = 4)	1 (25.0)	3 (75.0)
6.2–10.0 (n = 6)	4 (66.7)	2 (33.3)
>10.0 (n = 41)	30 (73.2)	11 (26.8)

Figure 3 Kaplan-Meier estimates of survival of hemodialysis patients during two-year follow-up with respect to all-cause mortality and serum concentrations of C-reactive protein (CRP). Significantly higher mortality was observed in patients with CRP >6.2 mg/L. Dashed line: group 1 (CRP <3.0 mg/L); full line: group 2 (CRP 3.0–6.1 mg/L); dotted line: group 3 (CRP 6.2–10.0 mg/L); dot-dash line: group 4 (CRP >10.0 mg/L). p<0.001 for group 3 vs. groups 1 and 2 and for group 4 vs. groups 1 and 2.

Figure 4 Mean values and distribution of C-reactive protein (CRP) in 173 survivors and 59 non-survivors at the beginning of hemodialysis treatment. Median serum concentration of CRP in non-survivors was significantly higher (open box) than CRP concentration in survivors (full box): 19.0 (1.5–99.7) mg/L vs. 2.3 (0.1–49.1) mg/L, respectively. p<0.001, Mann-Whitney U test.