Anemia in the Elderly

Abstract

Anemia affects a substantial fraction of the elderly population, representing a public health problem that is predicted to further increase in coming years because of the demographic drive. Being typically mild, it is falsely perceived as a minor problem, particularly in the elderly with multimorbidity, so that it often remains unrecognized and untreated. Indeed, mounting evidence indicates that anemia in the elderly (AE) is independently associated with disability and other major negative outcomes, including mortality. AE is generally multifactorial, but initial studies suggested that etiology remains unexplained in near one-third of cases. This proportion is consistently declining due to recent advances highlighting the role of several conditions including clonal hematopoiesis, "inflammaging," correctable androgen deficiency in men, and under-recognized iron deficiency. Starting from a real-world case vignette illustrating a paradigmatic example of anemia in an elderly patient with multimorbidity, we review the main clinical and pathophysiological aspect of AE, giving some practical insights into how to manage similar cases.

Figure 1

Curve of mortality risk per Hb categories in men aged > 66 years from the Calgary Community. The curve is J-shaped, with optimal Hb levels minimizing the risk ranging from 140 to 170 g/L (green area). Red point and arrow indicate how the patient described in the case vignette is positioned in the curve, with an ensuing mortality risk increased by 3-fold. ∗Adjusted for age, diabetes mellitus, glomerular filtration rate, and comorbidity status calculated using a validated chronic disease score. See also discussion on the “Definition of AE: a still unresolved issue,” “Prevalence of anemia in elderly: a public health problem,” and “Clinical relevance of anemia in elderly: not an innocent bystander” sections. Adapted from Culleton et al. In the original publication, the fully adjusted hazard ratio for mortality in all subjects (both men and women) older than 80 years with Hb < 110 g/L and normal glomerular filtration rate was 3.34, 95% confidence interval 2.47 to 4.51. Hb = hemoglobin.

Figure 2

The complex and multifactorial pathophysiology of AE. Some of the major factors contributing to AE etiology are illustrated. More than 1 condition is frequently present in individual patients, particularly in those with multimorbidity. See also discussion on the “Etiology of anemia in elderly: ‘Unexplained’ or inadequately studied?” section. AE = anemia in elderly.