Extra-skeletal impact of vitamin D supplementation protocol in an adult population with cystic fibrosis

Safety and efficacy of a new supplementation protocol in patients with cystic fibrosis and vitamin D deficiency

OBJECTIVES

Based on the European and American Cystic Fibrosis (CF) consensus recommendations, an increase in vitamin D (VD) supplementation in patients with CF and insufficient or defficient levels was proposed. The objective of our study was to determine the safety and efficacy of this new protocol.

MATERIAL AND METHODS

Multicentre nonrandomized uncontrolled experimental study. Patients with insufficient levels (<30 ng/mL) received increasing doses of VD (between 800 and 10 000 IU/day). Patients were followed up for 12 months, during which their vitamin and nutritional status, pulmonary function and calcium and phosphate metabolism were assessed.

STATISTICAL ANALYSIS

t test for paired data and multivariate logistic regression analysis.

RESULTS

Thirty patients aged 1-39 years (median, 9.1) completed the follow-up. Two patients were dropped from the study on account of 25-OH VD levels greater than 100 ng/mL at 3 months without clinical or laboratory signs of hypercalcaemia. At 12 months, we observed an increase of 7.6 ng/mL (95% CI, 4.6-10 ng/mL) in the mean 25-OH VD level and an improvement in vitamin status: 37% achieved levels of 30 ng/mL or greater, 50% levels between 20 and 30 ng/mL and 13% remained with levels of less than 20 ng/mL. We found no association between improved VD levels and pulmonary function.

CONCLUSIONS

The proposed protocol achieved an increase in serum VD levels and a decrease in the percentage of patients with VD insufficiency, although it was still far from reaching the percentages of sufficiency recommended for this entity.

Vitamin D Status in Pediatric and Young Adult Cystic Fibrosis Patients. Are the New Recommendations Effective?

Introduction: In recent years, guidelines for vitamin D supplementation have been updated and prophylactic recommended doses have been increased in patients with cystic fibrosis (CF). Objective: To evaluate safety and efficacy of these new recommendations. Results: Two cohorts of pancreatic insufficient CF patients were compared before (cohort 1: 179 patients) and after (cohort 2: 71 patients) American CF Foundation and European CF Society recommendations were published. Cohort 2 patients received higher Vitamin D doses: 1509 (1306–1711 95% CI) vs 1084 (983–1184 95% CI) IU/Day (p < 0.001), had higher 25 OH vitamin D levels: 30.6 (27.9–33.26 95% CI) vs. 27.4 (25.9–28.8 95% CI) ng/mL (p = 0.028), and had a lower prevalence of insufficient vitamin D levels (<30 ng/mL): 48% vs 65% (p = 0.011). Adjusted by confounding factors, patients in cohort 1 had a higher risk of vitamin D insufficiency: OR 2.23 (1.09–4.57 95% CI) (p = 0.028). Conclusion: After the implementation of new guidelines, CF patients received higher doses of vitamin D and a risk of vitamin D insufficiency decreased. Despite this, almost a third of CF patients still do not reach sufficient serum calcidiol levels.

A Clinician’s guide to vitamin D supplementation for patients with cystic fibrosis

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Vitamin D deficiency is multifactorial in the cystic fibrosis population.

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Vitamin D deficiency can adversely affect multiple organ systems in the cystic fibrosis population.

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In the cystic fibrosis population in the United States, we aim to treat to serum 25-hydroxyvitamin D levels over 30 ng/ml.

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Cholecalciferol is used in preference to ergocalciferol.

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Daily or once weekly dosing regimens are chosen according to patient preference and compliance.

Vitamin D deficiency is common in the general population, and even more so in patients with cystic fibrosis. Deficiency is exacerbated in cystic fibrosis patients because of a myriad of causes including malabsorption, decreased fat mass, reduced 25-hydroxylation of vitamin D, reduced exposure to sunlight, decreased vitamin D binding protein, and exposure to drugs that increase catabolism. In turn, vitamin D deficiency can contribute to poor bone health. Additionally, it may contribute to pulmonary decline in the form of worsening pulmonary function, increased colonization with pathogens, and increased pulmonary exacerbation. Because vitamin D deficiency is correlated with negative clinical effects in multiple organ systems of patients with cystic fibrosis, it is important to screen for and treat deficiency in these patients. The Cystic Fibrosis Foundation has issued guidelines for the treatment of vitamin D deficiency, targeting serum levels of 25-hydroxyvitamin D of at least 30 ng/ml. The guidelines offer age-specific escalating dose regimens depending on serum vitamin D levels, with monitoring at 12- week intervals after changing therapy. They address the literature on alternative vitamin D sources, such as UV lamps, ideal formulations (cholecalciferol in preference to ergocalciferol), and optimal vehicles of administration. Despite these detailed recommendations, most centers are still unable to achieve in-target serum vitamin D levels for many of their patients. Future research examining ideal treatment regimens to achieve serum targets and maximize clinical effects are needed. Moreover, it is unknown whether vitamin D sufficiency will be easier to achieve on new triple therapy cystic fibrosis drug combinations, and how these drugs will contribute to vitamin D-related clinical outcomes.

Targeting Vitamin D Deficiency to Limit Exacerbations in Respiratory Diseases: Utopia or Strategy With Potential?

Patients with respiratory diseases such as cystic fibrosis, chronic obstructive pulmonary disease, or asthma often experience an acute worsening of respiratory symptoms, termed exacerbations. Although the course of exacerbations is disease specific, they are mostly triggered by a respiratory infection. Exacerbations often require hospitalization and are an important cause of mortality. Treatments of exacerbations aim to minimize the negative impact and to prevent subsequent events. Despite many existing therapy options, many patients do not benefit from therapy and suffer from recurrent events. Vitamin D deficiency is a worldwide problem and is extremely prevalent in these patients. Vitamin D, known for its calcemic effects, also has immunomodulatory and anti-infectious actions and can therefore be a possible agent to treat or prevent exacerbations. This review will focus on vitamin D as a potential candidate to treat or prevent exacerbations in CF, COPD, and asthma.

Challenges with optimizing nutrition in cystic fibrosis

Introduction. Optimizing nutrition remains the cornerstone of therapy for patients with cystic fibrosis (CF) since it is associated with better pulmonary function and survival. However, a significant proportion of patients still fail to achieve normal growth and nutritional status. Areas covered. This review describes the current challenges in providing effective nutritional therapy in CF with a focus on the current issues related to energy imbalance, dietary composition, adherence to nutritional recommendations, pancreatic enzyme replacement therapy, and the effects of modulators of the CF transmembrane conductance regulator. Expert opinion. CF is a multisystemic disease that requires a personalized nutritional approach with accurate evaluation of energy balance. There is an urgent need for evidence-based recommendations on the dietary composition, in consideration of the increasing prevalence of overweight, diabetes and the potential effects of fatty acids on inflammation and immune response. More research into new pancreatic enzyme formulations is also required.