Prevalence of anaemia in primary care in England

Conference:

SAPC ASM 2024 - Bristol

Talk Code:

10F.1

Presenter:

Me (Margaret Smith)

Co-authors:

Cynthia Wright Drakesmith, Sarah Haynes, Katja Maurer, Suzanne Maynard, Noémi Roy, Akshay Shah, Simon Stanworth,Clare Bankhead

Author institutions:

Department of Primary Care Health Sciences, Nuffield Department of Women’s and Reproductive Health, Oxford University Hospital Haematology, Nuffield Department of Clinical Neurosciences, Radcliffe Department of Medicine (all University of Oxford)

Problem

Anaemia is a common condition of all ages where the body does not have enough healthy red blood cells. This may cause tiredness, shortness of breath and impaired concentration amongst other symptoms. Anaemia affects about 33% of the world’s population. The commonest type is iron-deficiency anaemia (IDA). It can be prevented or treated by an iron rich diet, but iron supplementation is often required. The other common type is anaemia of inflammation, which is related to chronic disease. Most research on IDA has focussed on low- and middle-income countries where it is one of the five leading causes of years lived with disability. However, anaemia prevalence in different demographic groups in the UK is not well known.

Approach

We used a population of patients from UK Primary Care practices, identified from a database of electronic health records. CPRD Aurum contains data on 39 million patients from 1485 practices and is roughly nationally representative. We described the prevalence of haemoglobin (Hb) testing in 2019 (pre-COVID) and anaemia prevalence (according to WHO age and gender-specific cut-offs for Hb) in different demographic subgroups. We estimated the percentage with low Hb in the first 3 months of 2019 who had another Hb test 3-6 months or 6-12 months later, and the percentage of these tests still below anaemia thresholds.

Findings

The study population contained 14,207,841 people age 1+ years from English practices. Overall 5.4% of females and 3.1% of males had an Hb test result below the WHO-threshold for anaemia. For example, 25% of 3,523,355 women aged 15-49 years were tested in 2019, and 18.0% had low Hb (4.5% of the total). Only 12.5% of 3,570,156 men aged 15-49 were tested, 4.3% having low Hb (0.5% of the total). Prevalence of testing and low Hb increased with age: 54.5% and 54.3% of women and men age 66+ years were tested, with 25.3% (13.8% of total) and 29.6% (16.1% of total) having low Hb. Women of Asian or black ethnicity were more likely to have had a test indicating low Hb, as were women in the highest quintile of IMD. A total of 207,054 people had a low Hb recorded in the first 3 months of 2019. Of those with follow up 3-6 months later, 35.6% had another Hb test, and Hb was still below threshold in 74.1% of these. Of those with follow-up 6-12 months after the initial low Hb result, 51.3% had another test, and it was still below threshold in 70.7% of people.

Consequences

Prevalence of anaemia and Hb testing varies considerably by sex, age-group, ethnicity and IMD, with a significant burden in women of childbearing age. Longitudinal data on test results indicates many people have persisting anaemia, raising questions about appropriate investigation and management.

Submitted by:

Margaret Smith

Funding acknowledgement:

CB and MS are supported by the Oxford and Thames Valley Applied Research Collaborative The work was done under CPRD ERAP protocol 22_001873