A public health problem
Anemia is a global public health problem affecting both developing and developed countries with major consequences for human health as well as social and economic development. It occurs at all stages of the life cycle, but is more prevalent in pregnant women and young children.
Anemia is an indicator of both poor nutrition and poor health. The most dramatic health effects of anemia, i.e., increased risk of maternal and child mortality due to severe anemia, have been well documented. In addition the negative consequences of iron deficiency anemia (IDA) on cognitive and physical development of children, and on physical performance, particularly work productivity in adults are of major concern.
Signs and symptoms
Though different types of anemia have different causes, the signs and symptoms can be very similar. Mild or moderate forms of anemia may cause few, if any, symptoms. Some of the most common symptoms are:
Other signs and symptoms that may develop as the anemia becomes more severe include a feeling of cold or numbness in hands and/or feet, shortness of breath, fast or irregular heartbeat, and chest pain.
Hemoglobin (Hb) concentration is the most reliable indicator of anemia at the population level, as opposed to clinical measures which are subjective and therefore have more room for error. Measuring Hb concentration is relatively easy and inexpensive, and this measurement is frequently used as a proxy indicator of iron deficiency. However, anemia can be caused by factors other than iron deficiency. In addition, in populations where the prevalence of inherited hemoglobinopathies is high, the mean level of Hb concentration may be lowered. This underlines that the etiology of anemia should be interpreted with caution if the only indicator used is Hb concentration. The main objective for assessing anemia is to inform decision-makers on the type of measures to be taken to prevent and control anemia. This implies that in addition to the measurement of Hb concentration, the causes of anemia need to be identified considering that they may vary according to the population.
Given the multifactorial nature of this disease, correcting anemia often requires an integrated approach. In order to effectively combat it, the contributing factors must be identified and addressed. In settings where iron deficiency is the most frequent cause, additional iron intake is usually provided through iron supplements to vulnerable groups; in particular pregnant women and young children. Food-based approaches to increase iron intake through food fortification and dietary diversification are important, sustainable strategies for preventing IDA in the general population. In settings where iron deficiency is not the only cause of anaemia, approaches that combine iron interventions with other measures are needed.
Strategies should include addressing other causes of anemia and should be built into the primary health care system and existing programs. These strategies should be tailored to local conditions, taking into account the specific etiology and prevalence of anemia in a given setting and population group.