L'anémie du sujet âgé : une étiologie peut en cacher une autre !

Anemia is common in patients older than 75 years. Patho-physiologic mechanisms of anaemia are similar to that involved in younger patients even though certain mechanisms are more common in the elderly. Practical decisional algorithms have to be used for the diagnosis of anaemia. Risk factors for anaemia have been identified in this group of age: institutionalization, bad socio-economic conditions, co-morbid conditions. Particular emphasis is given to several points: 1) the clinical tolerance of anaemia is the most important feature to take into account in older patients, rather than the decline of the haemoglobin level. Even if the haemoglobin level is only slightly decreased, an evaluation of anemia should be performed by the geriatrician, including, if needed, the achievement of a bone-marrow aspiration; 2) causes of anaemia are often multiple, due to frequent co-morbid conditions and acute illnesses, associated with nutritional deficiencies, inflammation… Chronic kidney disease and dysthyroïdia are also common; 3) nutritional deficiencies (iron, folate and/or B12 deficiency) are frequent and their cause has to be identified; 4) the prevalence of myelodysplastic syndromes, which are clonal diseases, is probably underestimated in this group of age.