Renal anaemia : The role of haemoglobin control in patients with chronic kidney disease

Abstract

Chronic kidney disease (CKD) is a significant and prevalent health problem in the world. Anaemia is one of the most common manifestations in patients with CKD. The correction of anaemia with erythropoietin normalises haemoglobin level and improves quality of life. Many aspects of the impact of anaemia treatment with erythropoiesis-stimulating agents on the progression of CKD remain unresolved and disputable. The present study is a retrospective chart review of 1654 outpatients with CKD. The data were collected from the Centre of Nephrology between 1 January 2002 and 31 December 2006. The aims of the study were to assess the causes of CKD; the prevalence of anaemia based on the current guidelines for anaemia management in CKD (Kidney Disease Dialysis Outcomes Quality Initiative; K/DOQI); to evaluate haemoglobin (Hb), systolic and diastolic blood pressure (SBP and DBP), glomerular filtration rate (GFR) at the first referral to a nephrologist and at the start of renal replacement therapy (RRT). The most common causes of CKD were arterial hypertension (17.2%), chronic glomerulonephritis (17.2%), chronic intersticial nephritis (13.3%), and diabetes (12.8%). Twenty-three percent of end-stage renal disease (ESRD) patients had diabetes mellitus. At the first visit in the renal department, 16% of the patients had an advanced degree of CKD (GFR <30 ml/min). The proportion of patients under an observation in the kidney centre for a period of six months and more was only 34% (554 of 1654). Hypertension was recorded in 72% of study subjects. The blood pressure (BP) values in patients at the first visit (n = 1633) vs. at the start of RRT (n = 154) were: mean SBP 147.4 ± 24.8 mm Hg vs. 152.2 ± 23.0 mm Hg (P < 0.05); mean DBP 88.8 ± 13.6 mm Hg vs. 88.4 ± 12.0 mm Hg (P 0.05). Anaemia was recorded in 41% of study subjects, estimated using K/DOQI recommendations. The prevalence of anaemia was increased from 30.2% to 44.8% of study patients with a rise of BP (from normal BP to hypertension; P < 0.05). The mean Hb level at the start of RRT was 9.8 ± 2.1 g/dl. Only 18% of patients with renal anaemia had used erythropoiesis-stimulating agents before RRT (28 of 155). Anaemia is the prevalent condition at moderate degrees of CKD. The severity of anaemia in the CKD population is determined by evidence of diabetes, cardiovascular disease, and renal function. Anaemia may often be unrecognised or untreated.