Iron deficiency anaemia (IDA) affects approximately 4.7 million of people in the UK, with children and pre-menopausal women being at higher risk (1). Each year more than 6.8 million prescriptions for oral iron are filled in England alone (NHS Information Centre data). However, gastrointestinal symptoms limit adherence in 10-30% of otherwise healthy patients (2-4) and in up to 50% of patients with gastrointestinal disorders (5). Simple ferrous iron salts constitute the vast majority of currently prescribed oral iron because these are cheap and well absorbed. However, they are also poorly tolerated and thus, we believe, are expensive to the NHS.

Funded by the Medical Research Council, we have developed an alternative oral iron supplement, that we name IHAT (iron hydroxide adipate tartrate), as an efficacious therapy for IDA with minimal side-effects.

In the study proposed here we aim to assess the total health cost associated with current oral iron supplements and, hence, define the clinical unmet need for alternative treatments. We will use Clinical Practice Research Datalink (CPRD) GOLD data to (i) estimate the pattern of prescribing to oral iron in primary care in the general population and (ii) develop a health economics model in pre-menopausal women. These data will provide evidence for the total health system costs associated with current oral iron treatment. Furthermore, this study will provide data from which the cost-effectiveness and total health system costs of alternative effective and treatments with minimal side-effects could be estimated.

Our research objective is to gather evidence for the unmet clinical need for safe, low-side-effect oral iron in the UK.

To achieve this objective we aim to determine:

1. Pattern of prescribing to oral iron in primary care in GP practices in England: estimate prescription rates, efficacy and intolerance of treatment with all forms of currently prescribed oral iron.
2. Health economics of the use of ferrous iron salts in primary care: estimate patterns of individual response to treatment; determine the costs of ferrous iron (sulphate, fumarate and gluconate) therapy in pre-menopausal women in primary care, and develop a cost-effectiveness model for alternative treatments with minimal side-effects.

Inclusion Criteria:

• patients prescribed oral iron in primary care practices included in the UK CPRD database

Exclusion Criteria:

• N/A

For the 1-year cohort study we are not defining a sub-population group and will investigate all individuals (adults and children) prescribed any type of oral iron at least once in the time period assessed, although a breakdown by key sociodemographic (age, gender, ethnicity) will be conducted.

For the 10-year plus cohort study, pre-menopausal women in receipt of ferrous iron supplements are our study population of interest.

Pre-menopausal women are the population group with the largest number of individuals affected (nearly 2M) by IDA in the UK, mainly because dietary iron intake does not sufficiently offset menorrhagic iron losses.