The impact of plasma 25-hydroxyvitamin D on pulmonary function and exercise physiology in cystic fibrosis: a multicentre retrospective study

Background: a 25-hydroxyvitamin D (25OHD) may exert immunomodulatory effects on respiratory health, which may translate to improvements in exercise physiology. Thus, we aimed to investigate whether plasma 25OHD is associated with lung function and aerobic fitness in people with cystic fibrosis (pwCF). Methods: a multicentre retrospective review of pwCF (&gt; 9 years old) attending the Royal Hospital for Sick Children (Edinburgh) or Wessex CF-Unit (Southampton) was performed between July 2017 and October 2019. Demographic and clinical data were collected. Plasma 25OHD measured closest in time to clinical cardiopulmonary exercise testing and/or spirometry [forced expiratory volume (FEV1)% predicted] was recorded. Pancreatic insufficiency was diagnosed based on faecal elastase of &lt; 100 µg g−1. We performed multiple-regression analysis with aerobic fitness outcomes [peak oxygen uptake (VO2 peak)] and FEV1% predicted as primary outcomes. Results: ninety pwCF [mean ± SD age: 19.1 ± 8.6 years, 54 (60%) children, 48 (53%) males and 88 (98%) Caucasian] were included. 25OHD deficiency and insufficiency was 15 (17%) and 44 (49%), respectively. 25OHD deficiency and insufficiency was significantly associated with pancreatic insufficiency (χ2 = 4.8, p = 0.02). Plasma 25OHD was not significantly associated with FEV1% predicted (r2 = 0.06, p = 0.42, 95% CI = −0.09 to 0.19) or VO2 peak (r2 = 0.04, p = 0.07, 95% CI = −011 to 0.005) in all pwCF. However, 25OHD was significantly associated with both FEV1% (r2 = 0.15, p = 0.02, 95% CI = 1.99–2.64) and VO2 peak (r2 = 0.13, p = 0.05, 95% CI = −0.26 to −0.005) in the paediatric cohort. Conclusions: we showed that 25OHD is associated with improved lung function and aerobic fitness in children and adolescents with CF. Mechanistic and high-quality prospective studies including both lung function and aerobic fitness as primary outcomes are now warranted.</p

Overall and differentiated sensory responses to cardiopulmonary exercise test in patients with cystic fibrosis: kinetics and ability to predict peak oxygen uptake

International audienc

Cystic fibrosis and physiological responses to exercise.

Journal ArticleCopyright © 2014 Informa Plc. All rights reserved.Cardiopulmonary exercise testing is underutilized within the clinical management of patients with cystic fibrosis. But within the last 5 years, there has been considerable interest in its implementation, which has included deliberations by the European Cystic Fibrosis Society about incorporating this method within the clinical assessment of patients. This review examines the current use of cardiopulmonary exercise testing in assessing the extent and cause(s) of exercise limitation from a pediatric perspective. Examples of the measured parameters and their interpretation are provided. Critical synthesis of recent work in the oxygen uptake (VO2) kinetics response to and following exercise is also discussed, and although identified more as a research tool, its utilization advances researchers understanding of the cardiovascular, respiratory and muscular limitations to exercise tolerance. Finally, exercise and its application in therapeutic interventions are highlighted and a number of recommendations made about the utility of exercise prescription