ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Endocrine Abstracts (2017) 52 P27 | DOI: 10.1530/endoabs.52.P27

Supplementation of vitamin D deficiency/insufficiency in patients with GEP-NET using over the counter vitamin D3 preparations

Helen L Robbins1, Megan Symington1, Barbara Mosterman1, Josie Goodby1, Louise davies1, Georgios K Dimitriadis1,2,3, Grigorios Kaltsas1, Harpal S Randeva1,2,3 & Martin O Weickert1,2,3

1The ARDEN NET Centre, European Neuroendocrine Tumour Society (ENETS) Centre of Excellence (CoE); University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK; 2Clinical Sciences Research Laboratories, Warwick Medical School, University of Warwick, University Hospital, Coventry, UK; 3Coventry University, Centre for Applied Biological & Exercise Sciences, Coventry, UK.

Vitamin D (vit-D) deficiency is common in patients with gastro-entero-pancreatic neuroendocrine tumours (GEP-NET) and has been linked to reduced survival in these patients. Vit-D status was assessed in 183 patients with GEP-NET, at the time of their first presentation in the ARDEN-NET-Centre; and following simple advice at routine 6-monthly follow-up appointments to increase vit-D intake using over-the-counter vit-D preparations (Colecalciferol (Vit-D3), 1000–2000 units/day), over a prospective observation period of 24-months. At baseline, 67% of the patients were either vit-D insufficient (31%; 25-OH-vit- D 25–50 nmol/l) or deficient (36%; 25-OH-vit-D<25 nmol/l). 25-OH-vit-D significantly increased from 38±4 nmol/l at baseline to 60±6 nmol/l (P<0.0001) and 57±7 nmol/l (P=0.039) after 12 and 24-months, respectively. Percentage of vit-D insufficiency decreased from 66.6% at baseline to 44.9 and 46.2% after 12 and 24 months, respectively. Previous abdominal surgery was the only significant predictor of serum 25-OH-vit-D concentrations in bootstrapped linear regression analyses (P=0.037). In summary: simple advice to increase vit-D intake using over-the-counter preparations significantly improved highly prevalent vit-D deficiency/insufficiency in GEP-NET patients; although, 15% of patients remained deficient and should be considered for additional measures of vit-D replacement.