Severe anemia in new end-stage renal disease patients

Premise: Anemia is a common abnormality observed in patients with end-stage renal disease (ESRD). However, data on ESRD patients with severe anemia (SA), which is arbitrarily defined as a hemoglobin (Hb) ≤4 g/dl and/or a hematocrit (Hct) ≤12%, are limited. Methods & Materials: We conducted a case-control study in new ESRD patients at a medical center from July 1988 to December 1996. A total of 17 ESRD patients were found to have SA. A control group of 51 new ESRD patients without SA who were matched with regard to age (within 3 years), gender, and the starting date (within 6 months) of renal replacement therapy (RRT) were recruited. Those study subjects who had a history of having received blood transfusions or erythropoietin (EPO) therapy were excluded from the study. We found that the SA patients were younger in comparison with the general hemodialysis patient population in Taiwan (mean age, 43.2 ± 13.0 vs. 57.4 ± 12.1 years). Chronic glomerulonephritis (64.7%) was the most common underlying renal disease. Dyspnea (88.2%) and weakness (82.4%) were the most common manifestations. Most (94.1 %) of the SA patients had used Chinese herbs for an extended period (15.1 months vs. 5.1 months, p<0.01), and all SA patients were referred late for treatment. Results: Patients with SA had higher mean blood urea nitrogen (208.9 mg/dl, vs. 136.8 mg/dl, p<0.01), serum creatinine (24.8 mg/dl vs. 16.6 mg/dl, p<0.01), serum phosphate (11.7 mg/dl vs. 9.4 mg/dl, p<0.05), iPTH (493.4 pg/ml vs. 287.3 pg/ml, p<0.01), lower blood pH value (7.2 vs. 7.3, p<0.01), and a higher cardiothoracic ratio (61.1% vs. 53.9%, p<0.05). They also had a higher prevalence of left ventricular hypertrophy (LVH; 82.0% vs. 31.4%, p<0.01). However, none of the SA patients had early mortality, defined as death within 1 month after starting RRT. Furthermore, the two groups had similar hospital stays (20.1 days vs. 21.8 days) and long-term survival. Conclusions: In brief, late referral combined with several metabolic factors may contribute to the development of SA. As anemia worsens, the prevalence of LVH and cardiomegaly at the start of RRT increases. However, EPO therapy and RRT in ESRD patients can reduce the impact of SA on long-term survival. In addition, we found that an age above 40 years and hypoalbuminemia (<3 g/dl) were significant predictors for poor long-term survival in ESRD patients.