Challenges with optimizing nutrition in cystic fibrosis

Exocrine Pancreatic Insufficiency Dosing Guidelines for Pancreatic Enzyme Replacement Therapy Vary Widely Across Disease Types

BACKGROUND

Pancreatic enzyme replacement therapy (PERT) is the standard treatment for exocrine pancreatic insufficiency (EPI). However, many individuals are inadequately treated, with gaps in clinical dosing, guidelines, and tools to aid individual titration.

METHODS

A systematic review identified research and guidelines on PERT dosing recommendations across conditions, systematically reviewing and synthesizing total PERT intake, meal/snack guidelines, and changes over time to provide an up-to-date look at the most common doses used in studies and guidelines.

RESULTS

This review of 257 articles found wide variability in PERT dosing guidelines within and across conditions. Many patients with EPI are underdosed, with guidelines differing globally and by disease type, and clinician prescribing may also play a role. The most common dosing guidelines focus on starting doses at 40,000-50,000 units of lipase/meal with increases of up to two to three times this amount before pursuing additive therapies. Guidelines and studies typically focus only on fat digestion, and comparison by total daily dose shows underdosing is common. Most PERT studies are on safety and efficacy rather than optimal titration.

CONCLUSION

The current guidelines for PERT in EPI demonstrate substantial variability in dosing recommendations, both within and across disease types. This variation highlights the need for further research to optimize PERT dosing and improve patient outcomes. Healthcare providers should consider individualizing PERT dosing based on nutritional status and response to therapy, ensuring regular follow-up with patients for dose titrations with consideration that most guidelines are framed as initial doses rather than upper limits.

Can Bioactive Food Substances Contribute to Cystic Fibrosis-Related Cardiovascular Disease Prevention?

Advances in cystic fibrosis (CF) care have significantly improved the quality of life and life expectancy of patients. Nutritional therapy based on a high-calorie, high-fat diet, antibiotics, as well as new therapies focused on CFTR modulators change the natural course of the disease. They do so by improving pulmonary function and growing BMI. However, the increased weight of such patients can lead to unwanted long-term cardiovascular effects. People with CF (pwCF) experience several cardiovascular risk factors. Such factors include a high-fat diet and increased dietary intake, altered lipid metabolism, a decrease in the level of fat-soluble antioxidants, heightened systemic inflammation, therapeutic interventions, and diabetes mellitus. PwCF must pay special attention to food and eating habits in order to maintain a nutritional status that is as close as possible to the proper physiological one. They also have to benefit from appropriate nutritional counseling, which is essential in the evolution and prognosis of the disease. Growing evidence collected in the last years shows that many bioactive food components, such as phytochemicals, polyunsaturated fatty acids, and antioxidants have favorable effects in the management of CF. An important positive effect is cardiovascular prevention. The possibility of preventing/reducing cardiovascular risk in CF patients enhances both quality of life and life expectancy in the long run.

Updates in Nutrition Management of Cystic Fibrosis in the Highly Effective Modulator Era

Attainment and maintenance of good nutrition has been an important aspect of management in cystic fibrosis (CF) for decades. In the era of highly effective modulator therapy for CF, the quality of the nutrients we recommend is increasingly important. Our therapy must support our patients' health for many years beyond what we previously thought. Preventing cardiovascular disease, reducing hyperlipidemia, and optimizing lean body mass for active, longer lives now join the long-standing goal of promoting lung function through nutrition. This chapter summarizes recent developments in nutrition in people with CF, with an eye to the evolution of our practice.

Nutrition in Cystic Fibrosis—Some Notes on the Fat Recommendations

Nutrition is important in cystic fibrosis (CF) because the disease is associated with a higher energy consumption, special nutritional deficiencies, and malabsorption mainly related to pancreatic insufficiency. The clinical course with deterioration of lung function has been shown to relate to nutrition. Despite general recommendation of high energy intake, the clinical deterioration is difficult to restrain suggesting that special needs have not been identified and specified. It is well-known that the CF phenotype is associated with lipid abnormalities, especially in the essential or conditionally essential fatty acids. This review will concentrate on the qualitative aspects of fat metabolism, which has mainly been neglected in dietary fat recommendations focusing on fat quantity. For more than 60 years it has been known and confirmed that the patients have a deficiency of linoleic acid, an n-6 essential fatty acid of importance for membrane structure and function. The ratio between arachidonic acid and docosahexaenoic acid, conditionally essential fatty acids of the n-6 and n-3 series, respectively, is often increased. The recently discovered relations between the CFTR modulators and lipid metabolism raise new interests in this field and together with new technology provide possibilities to specify further specify personalized therapy.

Prevalence and factors associated with urinary incontinence in females with cystic fibrosis: An Italian single-center cross-sectional analysis

BACKGROUND

Individuals with cystic fibrosis (CF) are deemed to have a higher risk of developing urinary incontinence (UI), likely due to repeated increasing pressure on the pelvic floor. We aimed to determine the prevalence of female UI in a large CF referral center, and to assess the association between UI and severity of CF disease.

METHODS

We consecutively recruited female patients regularly attending our CF center, aged ≥6 years and with a confirmed diagnosis of CF. Prevalence, severity, and impact of UI were assessed by administering two validated questionnaires. Relationship between variables was evaluated by means of multiple correspondence analysis, whereas a logistic model was fitted to capture the statistical association between UI and independent variables.

RESULTS

UI was present in 51/153 (33%, 95% confidence interval [CI]: 26%-41%) females. Among children and adolescents, the prevalence was 12/82 (15%, 95% CI: 8%-25%) whereas among adults was 39/71 (55%, 95% CI: 43%-67%). The only explanatory variable associated with UI was age, with children presenting the lowest risk (odds ratio, 0.32; 95% CI: 0.05-0.93). Females presenting low or high nutritional status show higher profile risk of having UI.

CONCLUSIONS

Stress UI is a common complication in females with CF since childhood. Although it frequently occurs in older patients with a more severe phenotype, much attention should be paid to adults and to their nutritional status.

Adult Patients Affected by Cystic Fibrosis in Therapy with Cystic Fibrosis Transmembrane Regulator Modulators and Lung Transplant: Renal Function, Metabolic and Nutritional Status

Background. Cystic fibrosis (CF) is one of the most frequent genetic diseases. The discovery and implementation of new therapies prolonged the survival of CF patients in the last years. Evaluation of long-term complications could be useful to improve the outcome of these patients. Aim of the Study. To evaluate renal function, metabolic, nutritional, and inflammatory status in CF patients on cystic fibrosis transmembrane regulator (CFTR) modulators therapy as well as lung transplant recipients (LRs) and patients on conservative therapy (control group). Materials and Methods. We performed a prospective, longitudinal study on 69 CF patients. Clinical and laboratory parameters (metabolic and nutritional indices and inflammatory markers) were evaluated in all patients before starting CFTR therapy or transplant (T0) and after 3 years (T1). Results. We enrolled 69 CF patients (42 males). Patients were distributed into three groups. The average age was 35.01 ± 10.57 years for the control group (group 0), 32.47 ± 9.40 years for patients on CFTR modulators therapy (group 1), and 38.93 ± 7.14 years for LRs (group 2). At T1, we showed a significant difference among the three groups in terms of renal function indices: creatinine, eGFR, serum nitrogen as well as serum uric acid, sodium, and potassium ( $p<0.001$ , $p<0.001$ , $p<0.001$ , $p<0.001$ , $p<0.001$ , and $p<0.001$ , respectively), particularly in LRs patients. Significant differences were found in nutritional status parameters among the three groups: total protein, serum albumin, serum fibrinogen, serum transferrin, and white blood cell counts ( $p<0.001$ , $p=0.037$ , $p=0.04$ , $p=0.003$ , and $p=0.007$ , respectively), particularly in LRs compared with other groups. Moreover, we found significant differences in metabolic profile (HbA1c, $p=0.026$ ) and inflammatory status, with a significant difference in C-reactive protein values, neutrophil counts, and neutrophil-lymphocyte ratio (NLR) among the three groups ( $p<0.001$ , $p=0.005$ , and $p=0.026$ , respectively). Conclusions. Our study showed a reduced renal function and poor nutritional status in LRs, along with worse metabolic control. Moreover, we showed a lower inflammatory status in patients on CFTR modulators therapy. Therefore, we suggest early and careful monitoring of renal function, metabolic, and nutritional parameters in CF patients, whether they are on conservative therapy, CFTR modulators therapy, and LRs patients.