Oral calorie supplements for cystic fibrosis

Poor nutrition occurs frequently in people with cystic fibrosis and is associated with other adverse outcomes. Oral calorie supplements are used to increase total daily calorie intake and improve weight gain. However, they are expensive and there are concerns they may reduce the amount of food eaten and not improve overall energy intake. This is an update of a previously published review.

To establish whether in people with cystic fibrosis, oral calorie supplements: increase daily calorie intake; and improve overall nutritional intake, nutritional indices, lung function, survival and quality of life. To assess adverse effects associated with using these supplements.

We searched the Cochrane Cystic Fibrosis Trials Register comprising references from comprehensive electronic database searches, handsearches of relevant journals and abstract books of conference proceedings. We contacted companies marketing oral calorie supplements.Last search: 18 October 2016.

Randomised or quasi-randomised controlled trials comparing use of oral calorie supplements for at least one month to increase calorie intake with no specific intervention or additional nutritional advice in people with cystic fibrosis.

We independently selected the included trials, assessed risk of bias and extracted data. We contacted the authors of included trials and obtained additional information for two trials.

We identified 21 trials and included three, reporting results from 131 participants lasting between three months and one year. Two trials compared supplements to additional nutritional advice and one to no intervention. Two of the included trials recruited only children. In one trial the risk of bias was low across all domains, in a second trial the risk of bias was largely unclear and in the third mainly low. Blinding of participants was unclear in two of the trials. Also, in one trial the clinical condition of groups appeared to be unevenly balanced at baseline and in another trial there were concerns surrounding allocation concealment. There were no significant differences between people receiving supplements or dietary advice alone for change in weight, height, body mass index, z score or other indices of nutrition or growth. Changes in weight (kg) at three, six and 12 months respectively were: mean difference (MD) 0.32 (95% confidence interval (CI) -0.09 to 0.72); MD 0.47 (95% CI -0.07 to 1.02 ); and MD 0.16 (-0.68 to 1.00). Total calorie intake was greater in people taking supplements at 12 months, MD 265.70 (95% CI 42.94 to 488.46). There were no significant differences between the groups for anthropometric measures of body composition, lung function, gastro-intestinal adverse effects or activity levels. Moderate quality evidence exists for the outcomes of changes in weight and height and low quality evidence exists for the outcomes of change in total calories, total fat and total protein intake as results are applicable only to children between the ages of 2 and 15 years and many post-treatment diet diaries were not returned. Evidence for the rate of adverse events in the treatment groups was extremely limited and judged to be of very low quality AUTHORS' CONCLUSIONS: Oral calorie supplements do not confer any additional benefit in the nutritional management of moderately malnourished children with cystic fibrosis over and above the use of dietary advice and monitoring alone. While nutritional supplements may be used, they should not be regarded as essential. Further randomised controlled trials are needed to establish the role of short-term oral protein energy supplements in people with cystic fibrosis and acute weight loss and also for the long-term nutritional management of adults with cystic fibrosis or advanced lung disease, or both.