Therapeutic regimens for vitamin D deficiency in postmenopausal women: a systematic review

Introduction
We reviewed the most effective vitamin D3 regimen for vitamin D deficiency in postmenopausal women.

Material and methods
We searched for studies and clinical trials conducted on healthy postmenopausal women published on PubMed from 2000 to 2018 using the term “Vitamin D deficiency” combined with the following terms: “dose”, “supplement”, “supplementation”, “cholecalciferol” or “cholecalciferol dose”. We identified 1376 articles which matched the search criteria. Based on reviewing the title and abstract, 17 articles were eligible for a full-text review. Of those, 12 manuscripts were ultimately included.

Results
A majority of the studies (75%) reported using daily maintenance doses which were predominantly administered orally (83.3%). Two studies reported favorable results following therapy with a single oral dose of 300,000 IU. After one month, however, 25-hydroxy vitamin D [25(OH)D] was satisfactory; both studies failed to maintain adequate responses after 60 and 90 days. One study found that loading oral doses of 50,000 IU/day for 2 weeks followed by the same doses every 2 weeks for one year were effective. Five studies employed oral doses of 800 IU/day but none of them reported that this dose was adequate. Three studies used doses of 1000 IU/day but only two of them reported positive results. Three trials examined oral doses of 2000 IU/day and another 3 studies tested oral doses of 4000-4800 IU/day. All of them reported acceptable responses that lasted with continued treatment.

Conclusions
Oral maintenance doses of 2000-4800 IU/day satisfactorily corrected vitamin D deficiency and maintained 25(OH)D levels in postmenopausal women with continuous therapy.