Anaemia in chronic heart failure: what is its frequency in the UK and its underlying causes?

Abstract

We decided to survey cases of NYHA functional class IV CHF because Silverberg and colleagues suggested that anaemia was particularly common in this group.^{1, 2} A total of 269 CHF patients requiring acute admission to Ninewells Hospital, Dundee were selected at random retrospectively between June 1998 and December 2000. Those with CHF were targeted from discharge letters and from selection from admission files to the acute receiving ward in Ninewells Hospital. A haemoglobin concentration of 11 g/dl or less was selected as our cutoff for anaemia. This was a compromise figure because the reference range for haemoglobin usually has 12.5–13.5 g/dl as its lower limit, whereas clinical trials of anaemia treatment in haematology patients often use the cutoff of 10–11 g/dl as entry criteria. Our overall feeling was that clinicians would be unlikely to embark on erythropoietin treatment when the haemoglobin concentration was 11.5 g/dl, whereas they might institute such treatment in a symptomatic CHF patient with a haemoglobin concentration of 10.5 g/dl. This group was further subdivided into microcytic, normocytic, and macrocytic anaemia with a mean cell volume (MCV) < 76 fl, 76–96 fl, and > 96 fl, respectively. In each of these groups it was noted if any patients had renal impairment (creatinine on admission ≥ 160 μmol/l), whether ferritin was low for age or sex (see table 1 for reference values used at Ninewells Hospital), whether the B12 or folate concentrations were low (< 200 ng/l and < 2.1 μg/l, respectively), and if possible hypothyroidism was present (thyroid stimulating hormone (TSH) > 4 mu/l).