Self-reported use of vitamins and other nutritional supplements in adult patients with cystic fibrosis. Is daily practice in concordance with recommendations?

BACKGROUND: In cystic fibrosis (CF), prophylactic supplementation of the fat-soluble vitamins A, D, E, and K is recommended. Limited data is available describing vitamin prescription adherence by adult patients. The aim of this study was to assess the use of prescribed vitamins and other nutritional supplements by adult CF patients.

METHODS: All adult CF patients (n=111) registered at the Utrecht CF Center were invited to participate in a telephone survey on supplement use. Supplemental vitamin intakes were compared with recommendations. In a subsample, associations between supplemental intake and serum vitamin D and E values were assessed.

RESULTS: In this study 80% of the patients reported the use of vitamin and/or mineral supplements. Fat-soluble vitamins were used by 43% of pancreatic-sufficient (PS) and 81% of pancreatic-insufficient (PI) patients. Of PI patients reporting supplemental vitamin use, only 9% met the recommendations for vitamin A, 32% for vitamin D, 59% for vitamin E, and 81% for vitamin K. Multivitamin supplements were used by 42% of PI and by 29% of PS patients. Other nutritional supplements were rarely used.

CONCLUSION: A high percentage of PI patients use fat-soluble vitamins below recommendations. Therefore adequate monitoring of vitamin supplementation and status is warranted.