The use of regular vitamin A preparations for children and adults with cystic fibrosis

Cystic fibrosis can lead to certain vitamins, such as vitamin A, not being properly absorbed by the body. This can result in problems caused by vitamin deficiency. A lack of vitamin A (vitamin A deficiency) can cause specific problems such as eye and skin problems. It can also be associated with poorer general and respiratory health. Therefore people with cystic fibrosis are usually given regular vitamin A preparations from a very young age. However, too much vitamin A can also cause respiratory and bone problems. The review aimed to show whether giving vitamin A regularly to people with cystic fibrosis is beneficial or not. However, the authors did not find any relevant trials to include in the review. They are therefore unable to draw any conclusions regarding the routine administration of vitamin A supplements and recommend that until further evidence is available, local guidelines are followed regarding this practice.

Authors' conclusions: 

As there were no randomised or quasi-randomised controlled trials identified, we cannot draw any conclusions on the benefits (or otherwise) of regular administration of vitamin A in people with cystic fibrosis. Until further data are available, country or region specific guidelines on the use of vitamin A in people with cystic fibrosis should be followed.

Read the full abstract...

People with cystic fibrosis and pancreatic insufficiency are at risk of fat soluble vitamin deficiency as these vitamins (A, D, E and K) are co-absorbed with fat. Thus, some cystic fibrosis centres routinely administer these vitamins as supplements but the centres vary in their approach of addressing the possible development of deficiencies in these vitamins. Vitamin A deficiency causes predominantly eye and skin problems while supplementation of vitamin A to excessive levels may cause harm to the respiratory and skeletal systems in children. Thus a systematic review on vitamin A supplementation in people with cystic fibrosis would help guide clinical practice.


To determine if vitamin A supplementation in children and adults with cystic fibrosis:
1. reduces the frequency of vitamin A deficiency disorders;
2. improves general and respiratory health;
3. increases the frequency of vitamin A toxicity.

Search strategy: 

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register which comprises of references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings.

Date of the most recent search of the Group's Cystic Fibrosis Trials Register: 07 April 2014.

Selection criteria: 

All randomised or quasi-randomised controlled trials comparing all preparations of oral vitamin A used as a supplement compared to either no supplementation (or placebo) at any dose and for any duration, in children or adults with cystic fibrosis (defined by sweat tests or genetic testing) with and without pancreatic insufficiency.

Data collection and analysis: 

No relevant studies for inclusion were identified in the search.

Main results: 

No studies were included in this review.