Unexplained fatigue and hemoglobin: a primary care study.

The authors of this article investigated the relation between unexplained fatigue and the hemoglobin concentration in a general practice setting. They determined the hematologic parameters of 174 patients with unexplained fatigue in whom the general practitioners established an indication for hemoglobin measuring; a control group of 148 patients was used. Taking gender into consideration, the same distributions were found in both groups. This pattern was not influenced by the duration and severity of the symptom, the presence of other "anemic" symptoms, nor the opinion of the physicians about the likelihood of a low hemoglobin level. Hemoglobin levels below 7.0 mmol/l were not found. Obviously, in patients with unexplained fatigue the hypothesis "anemia" will rarely be confirmed.