According to research, a patient’s target body mass index (BMI) for cystic fibrosis (CF) should be reconsidered. While the prevalence of overweight and obesity among cystic fibrosis patients has been increasing, it is unclear whether there is any benefit to increasing weight above the normal reference range.
A new study found that patients with cystic fibrosis who were normal weight compared to those who were overweight or obese had a higher forced expiratory volume in the first second of expiration. Those who were normal weight were also at a higher risk of cystic fibrosis-related diabetes (CFRD) and pancreatic insufficiency (PI).
The researchers, led by Rita Nagy, MD, Institute for Translational Medicine, Szentagothai Centre, Medical School University of Pecs, called for more long-term studies to assess the potential adverse effects of higher BMI or higher fat mass in cystic fibrosis patients.
The Inspiration
The researchers discovered that the fatal inherited disease is caused by recessive genetic variants in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which affects one in every 3300 White newborns. This disease affects a variety of organs, including the lungs, digestive system, and reproductive system.
Airway infections, chronic inflammation, exocrine pancreatic insufficiency, and complications such as CF-related diabetes and CF-related liver disease are common, resulting in a low quality of life for these people.
The European Society for Clinical Nutrition and Metabolism, the European Cystic Fibrosis Society, and a number of other official organisations recognise the adult and paediatric dietary guideline that focuses on nutritional failure and makes no recommendations for the management of overweight or obese individuals.
Overweight and obesity have more than doubled in adults with cystic fibrosis over the last two decades, affecting 31.4 percent of the population. However, the researchers cautioned that the currently recommended high-fat, high-carbohydrate diet in those with CF could have a variety of effects on the body and even affect clinical outcomes.

The study’s investigators wanted to see if there was a link between altered BMI or body composition and clinical outcomes in cystic fibrosis patients. Data was extracted by two authors and validated by a third author.
In November 2020, researchers searched three databases for systematic reviews and meta-analyses: MEDLINE (via PubMed), Embase, and the Cochrane Central Register of Controlled Trials. Patients over the age of two who had cystic fibrosis and had altered body composition or BMI were compared to patients whose measured parameters were within the reference ranges.
The primary outcomes were pulmonary function, exocrine pancreatic insufficiency, and diabetes-related to cystic fibrosis. Before collecting data, odds ratios or weighted mean differences with 95 percent confidence intervals were calculated, and a hypothesis was developed.
Only the outcomes Of the 10,524 records identified, 61 met the criteria and were included in the analysis. The quantitative synthesis was then comprised of 17 studies. The meta-analysis and systematic review included 9114 patients.
When compared to those of normal weight, those who were overweight or obese had a higher forced expiratory volume in the first second of expiration. The analysis of pulmonary function revealed significant heterogeneity.
The findings show that nutritional status has an effect on organ function in cystic fibrosis patients. According to the researchers, a nutritional strategy that raises the BMI closer to the upper limit of normal BMI should be included in the daily protocol.
Further research into the long-term effects of higher BMI, body composition, and a high-fat diet is required to focus on any potentially harmful effects of these higher levels. According to the researchers, careful evaluation of body composition is required to be incorporated into everyday clinical practise.