Effect of CFTR Modulators on Anthropometric Parameters in Individuals with Cystic Fibrosis: An Evidence Analysis Center Systematic Review.

There is a strong positive association between nutrition status and lung function in cystic fibrosis (CF). Improvements in clinical care have increased longevity for individuals with CF, and it is unknown how cystic fibrosis transmembrane regulator (CFTR) modulation therapy affects nutrition status over time. The objective of this systematic review of the literature was to examine anthropometric (height, weight, and body mass index [BMI; calculated as kg/m2]) and body composition outcomes of CFTR modulation therapy. A literature search of Medline (Ovid), Embase, and CINAHL (EBSCO) databases was conducted for randomized controlled trials examining the effect of CFTR modulation therapy on anthropometric and body composition parameters, published in peer-reviewed journals from January 2002 until May 2018. Articles were screened, data were synthesized qualitatively, and evidence quality was graded by a team of content experts and systematic review methodologists. Significant weight gain with ivacaftor was noted in children and adults with at least 1 copy of G551D mutation. In adults with at least 1 copy of R117H the effect of ivacaftor on BMI was not significant. Effects on BMI were mixed in adults with class II mutations taking ivacaftor with lumacaftor. There was no significant change in BMI in children homozygous for F508del who took ivacaftor with tezacaftor. Elexacaftor-tezacaftor-ivacaftor increased BMI and body weight in individuals 12 years of age and older who were hetero- or homozygous for the F508del mutation. The effect of CFTR modulation therapy on anthropometric parameters depends on the genetic mutation and the type of modulation therapy used. More research is needed to understand the long-term clinical impact of these drugs on nutritional status, including body composition and the role of dietary intake.

Dietary Macronutrient Distribution and Nutrition Outcomes in Persons with Cystic Fibrosis: An Evidence Analysis Center Systematic Review.

Cystic fibrosis (CF) increases risk for undernutrition and malabsorption. Individuals with CF traditionally have been counseled to consume a high-fat diet. However, a new era of CF care has increased lifespan and decreased symptoms in many individuals with CF, necessitating a re-examination of the high-fat CF legacy diet. A literature search was conducted of Medline (Ovid), Embase, and CINAHL (EBSCO) databases to identify articles published from January 2002 to May 2018 in the English language examining the relationships between dietary macronutrient distribution and nutrition outcomes in individuals with CF. Articles were screened, risk of bias was assessed, data were synthesized narratively, and each outcome was graded for certainty of evidence. The databases search retrieved 2,519 articles, and 7 cross-sectional articles were included in the final narrative analysis. Three studies examined pediatric participants and 4 examined adults. None of the included studies reported on outcomes of mortality or quality of life. Very low certainty evidence described no apparent relationship between dietary macronutrient distribution and lung function, anthropometric measures, or lipid profile in individuals with CF. The current systematic review demonstrates wide ranges in the dietary macronutrient intakes of individuals with CF with little to no demonstrable relationship between macronutrient distribution and nutrition-related outcomes. No evidence is presented to substantiate an outcomes-related benefit to a higher fat-diet except in the context of achieving higher energy intakes in a lesser volume of food.

Academy of Nutrition and Dietetics: 2020 Cystic Fibrosis Evidence Analysis Center Evidence-Based Nutrition Practice Guideline.

The Academy of Nutrition and Dietetics Evidence Analysis Center conducted a systematic review of the literature to develop an evidence-based practice guideline for primary nutrition issues in cystic fibrosis (CF). This guideline is designed to complement and build upon existing evidence-based CF nutrition guidelines. The objective of this guideline was to provide recommendations for registered dietitian nutritionists in the United States delivering medical nutrition therapy to individuals with CF and their families that fill gaps in current evidence-based guidelines on topics that are crucial in order to improve health and prevent disease progression. This guideline provides 28 nutrition recommendations to guide medical nutrition therapy, including nutrition screening, nutrition assessment, and dietary intake. For topics outside the scope of this guideline, practitioners are referred to external, evidence-based recommendations. The CF landscape is evolving rapidly with breakthroughs in cystic fibrosis transmembrane regulator modulators changing CF at a cellular level. Medical nutrition therapy for individuals with CF from infancy through advanced age requires novel and individualized approaches. The Academy Evidence Analysis Library CF guidelines provide a framework for expanding upon current knowledge to determine effective nutrition strategies for individuals with CF through long and healthy futures.

Chronic Obstructive Pulmonary Disease: A 2019 Evidence Analysis Center Evidence-Based Practice Guideline.

Chronic obstructive pulmonary disease (COPD) is a progressive lung disorder in which patients are at high risk for both pulmonary and systemic complications of their disease. Medical nutrition therapy by a registered dietitian nutritionist can be an integral component of lifestyle treatment targeted at maintaining and improving outcomes, such as lung function, mortality, and quality of life. The Academy of Nutrition and Dietetics (Academy) convened an expert workgroup to conduct a systematic review to update the COPD Evidence-Based Nutrition Practice Guideline. This publication outlines the Academy's Evidence Analysis Library methods used to complete the systematic review and guideline and examines the recommendations and supporting evidence. A total of 14 recommendations were developed based on evidence from eight conclusions. Using the Nutrition Care Process as a framework for practice, recommendations rated as strong included assessing and monitoring and evaluating body weight and medical nutrition therapy by a registered dietitian nutritionist. Weak recommendations included predicting resting and total energy expenditure. All other recommendations were rated as fair. These included individualizing the calorie prescription and macronutrient composition of the diet; assessing and monitoring and evaluating energy intake, serum 25-hydroxyvitamin D levels, and frequency of exacerbations; and determining need for vitamin D supplementation. Fewer than one-third of the systematic review's conclusions could be used to support the recommendations due to conflicting results or limited or no evidence available. The Evidence Analysis Library 2019 COPD Evidence-Based Nutrition Practice Guideline is a valuable resource for registered dietitian nutritionists and other health care professionals caring for those with COPD.

Comparison of steatocrit and fat absorption in persons with cystic fibrosis.

BACKGROUND: Exocrine pancreatic insufficiency is a common problem in persons with cystic fibrosis causing malabsorption and poor growth. The 72-hour fecal fat study is the best qualitative measure of fat malabsorption used in clinical practice. This test has several drawbacks, which include cost and logistics. The steatocrit has been proposed as a rapid method to assess fat malabsorption. OBJECTIVES: The objective of this study was to determine whether the steatocrit is an accurate estimation of fat malabsorption in persons with cystic fibrosis. METHODS: Forty-nine stool samples for steatocrit processing were obtained from 72-hour fecal fat collections performed on twenty-seven persons with cystic fibrosis. Stools were weighed and homogenized with sand and water. The emulsified specimen was pipetted into heparinized capillary tubes and centrifuged for 15 minutes. The length of the fatty layer was compared to the length of the solid layer plus the fatty layer in each tube to determine the steatocrit value. Four steatocrit mixtures were evaluated: (1) standard steatocrit, (2) dilute steatocrit, (3) acid steatocrit, (4) dilute acid steatocrit. Steatocrit values were compared with the coefficient of fat absorption determined from the 72-hour fecal fat collection. RESULTS: The correlation coefficient of the steatocrit and the coefficient of fat absorption ranged from -.045 to -.491. Only the coefficient of fat absorption and the acid steatocrit had a significant correlation ( = 0.033). CONCLUSION: The steatocrit is an imprecise measure of fat absorption and not clinically useful in estimating steatorrhea.