Effectiveness of low-dose iron treatment in non-anaemic iron-deficient women: a prospective open-label single-arm trial.

BACKGROUND: Iron deficiency without anaemia is highly prevalent and is particularly associated with fatigue, cognitive impairment, or poor physical endurance. Standard oral iron therapy often results in intestinal irritation with associated side effects and premature discontinuation of therapy, therefore, optimal oral iron therapy with sufficient iron absorption and minimal side effects is desirable.

METHODS: Thirty-six iron-deficient non-anaemic premenopausal women (serum ferritin ≤30 ng/ml, haemoglobin ≥117 g/l) with normal body mass index (BMI) and no hypermenorrhea received 6 mg of elemental oral iron (corresponding to 18.6 mg ferrous sulphate) twice daily for 8 weeks.

RESULTS: Participants treated with low-dose iron had an average age of 28 years and a BMI of 21 kg/m2. Their serum ferritin and haemoglobin increased significantly from 18 ng/ml to 33 ng/ml (p <0.001) and from 135 g/l to 138 g/l (p = 0.014), respectively. Systolic blood pressure increased from 114 mmHg to 120 mmHg (p = 0.003). Self-reported health status improved after 8 weeks (p <0.001) and only one woman reported gastrointestinal side effects (3%).

CONCLUSION: This prospective open-label single-arm trial shows that oral iron treatment of 6 mg of elemental iron twice daily over 8 weeks is effective in iron-deficient non-anaemic women. Due to the negligible side effects, low-dose iron treatment is a valuable therapeutic option for iron-deficient non-anaemic women with normal BMI and menstruation. Further placebo-controlled studies with a larger number of participants are needed to confirm these results.

CLINICALTRIALS: gov NCT04636060.