Prevalence of anaemia and iron deficiency in Portugal: the EMPIRE study

Anaemia and iron deficiency are major public health problems with great implications on quality of life.

To establish the general prevalence of anaemia and iron deficiency in the adult Portuguese population and the prevalence by age, gender and region.

This was a population-based, cross-sectional study (EMPIRE study) based on a representative sample of 7980 adults residing in mainland Portugal, which were selected using a random route sampling method. Levels of haemoglobin, ferritin, creatinine and C-reactive protein were measured by Point-of-Care assays; participants also completed a questionnaire about demography and medical history.

The measured prevalence of anaemia was 19.9% (95% confidence interval: 19.0-20.8%); 84% of cases were previously undiagnosed. Anaemia was more prevalent among women (20.8%), young adults (18-34 years) (22.8-30.5%), older adults (21.0%), and pregnant women (54.2%). Anaemia varied across regions: from 15.5% in the Center region to 24.9% in the South. Iron deficiency was also highly prevalent: 16.7% (ferritin <15 ng/mL), 31.9% (<30 ng/mL), 53.3% (<50 ng/mL) and 84.3% (<100 ng/mL). Iron deficiency anaemia represented most anaemia cases: 29.0% (ferritin <15 ng/mL), 54.8% (<30 ng/mL), 75.4% (<50 ng/mL) and 92.5% (<100 ng/mL).

Anaemia and iron deficiency are highly prevalent in Portugal and largely undiagnosed. Women, young adults and older individuals are more prone to present these conditions and there are marked regional asymmetries. Nationwide strategies for prevention, diagnosis and treatment of these conditions should be implemented.