The prognostic impact of fluctuating levels of C-reactive protein in Brazilian haemodialysis patients: a prospective study.
BACKGROUND
A single elevated C-reactive protein (CRP) value predicts mortality in haemodialysis (HD) patients, but the relative importance of repeated vs occasional positive systemic inflammatory response findings is not known.


METHODS
To assess the influence on survival of occasional inflammation, CRP, serum albumin (S-Alb) and fibrinogen were analysed bimonthly in 180 HD patients (54% male, 49+/-14 years). Clinically significant inflammation was defined as CRP >5.1 mg/l, based on the receiver operating characteristics curve for CRP as predictor of death. Based on four consecutive measurements of CRP, patients were assigned into three groups: group 1 (n = 74; 41%), no inflammation (CRP < or = 5.1 mg/l in all measurements); group 2 (n = 65; 36%), occasional inflammation (1-3 measurements of CRP > 5.1 mg/l); and group 3 (n = 41; 23%), persistent inflammation (all measurements of CRP >5.1 mg/l). The nutritional status was evaluated by subjective global assessment (SGA) and body mass index (BMI), and the survival (21 months of follow-up) by Kaplan-Meier curve and Cox model.


RESULTS
The median and range of CRP values (mg/l) for group 1, 2 and 3 were: 3.2 (3.2-5.1), 3.6 (3.2-54.9) and 13.8 (5.2-82), respectively (P<0.001), whereas the prevalence of malnutrition, assessed by SGA and BMI, did not differ significantly between the groups. The survival rate by Kaplan-Meier analysis was significantly different among the groups (chi2 = 12.34; P = 0.0004). Patients in group 3 showed the highest mortality (34%; P = 0.001), compared with group 1 (8%) and group 2 (14%; P = 0.01), respectively, whereas there was no significant difference in mortality between groups 1 and 2. Age, CRP, S-Alb level and SGA were independent predictors of mortality.


CONCLUSIONS
The patients with a persistent elevation of CRP had a higher mortality rate than the patients with occasional CRP elevation. Thus, persistent, rather than occasional, inflammation is an important predictor of death in HD patients.
Nascimento
Marcelo M
MM
Division of Renal Medicine, Department of Clinical Science, Karolinska Institutet, Karolinka University Hospital Huddinge, Stockholm, Sweden.
Pecoits-Filho
Roberto
R
Qureshi
A Rashid
AR
Hayashi
Shirley Y
SY
Manfro
Roberto C
RC
Pachaly
Maria A
MA
Renner
Luciana
L
Stenvinkel
Peter
P
Lindholm
Bengt
B
Riella
Miguel C
MC
D001938:Brazil; D002097:C-Reactive Protein / Q000032:analysis*; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000401:mortality* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009752:Nutritional Status; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012372:ROC Curve; D006435:Renal Dialysis; D016019:Survival Analysis
D002097:C-Reactive Protein