Extra-skeletal impact of vitamin D supplementation protocol in an adult population with cystic fibrosis

• Published in: Clinical nutrition (Edinburgh, Scotland) Scotland), 2019-08, Vol.38 (4), p.1666-1671
• Main Authors: Lehoux Dubois, C., Labrèche, E., Boudreau, V., Colomba, J., Mailhot, M., Lavoie, A., Rabasa-Lhoret, R., Coriati, A.
• Format: Article
• Language: English
• Subjects: CF-related diabetes; Cystic fibrosis; Nutritional status; Pulmonary function; Vitamin D
• ISSN: 0261-5614; 1532-1983
• DOI: 10.1016/j.clnu.2018.08.013

Due to lack of vitamin D absorption in patients with cystic fibrosis (CF), vitamin D supplementation becomes necessary. Our aim was to study the association between serum vitamin D levels and key clinical factors, such as nutritional status, pulmonary function and pulmonary exacerbations (PEx) frequency, in an adult CF population. Prospective analysis of a published vitamin D (VitD3) supplementation protocol (N = 200 adult patients) over a follow-up period of 5 years. Data were collected from the medical files before (baseline) and after (follow-up) the implementation of the VitD3 supplementation protocol, between 2009 and 2014. Serum samples to measure vitamin D were also collected at baseline and follow-up. A positive relationship between serum vitamin D and lung function was observed at baseline (R = 0.158, P = 0.027), but it disappeared at follow-up (P = 0.454). There was no association between serum vitamin D levels and body mass index. At follow-up, patients with significantly higher serum vitamin D levels were women, older in age, had CF-related diabetes or had a history of recurring PEx. No direct link was observed between heightened serum vitamin D and lung function or BMI in an adult CF population. We suggest that better compliance to treatments and closer follow-up from health professionals could partially explain why such patients reached higher vitamin D serum levels.