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DOI: 10.1055/s-0042-1758729
Exercise and Airway Clearance Techniques in Cystic Fibrosis
Abstract
Exercise and airway clearance techniques (ACTs) have been a cornerstone of treatment for people with cystic fibrosis (pwCF) for many decades. Exercise may confer both respiratory and nonrespiratory benefits for pwCF, with greater exercise capacity associated with improved survival. A wide variety of exercise interventions for pwCF have been investigated. ACTs may assist in reducing respiratory symptoms for pwCF and are currently recommended to be performed daily, with the types of ACTs used varying globally. While recommended components of care, both exercise and ACTs are time-intensive and maintaining adherence to the recommendations over the longer term can be challenging. It has been proposed that with advances in the therapeutic options for pwCF, a rationalization of the therapeutic regimen may be possible. We summarize the current evidence for the use of exercise and ACTs by pwCF, discuss the implications of the introduction of cystic fibrosis transmembrane conductance regulator modulators on both exercise and ACTs, and highlight areas for further research.
Publication History
Article published online:
19 December 2022
© 2022. Thieme. All rights reserved.
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References
- 1 Elborn JS. Cystic fibrosis. Lancet 2016; 388 (10059): 2519-2531
- 2 Gruet M, Troosters T, Verges S. Peripheral muscle abnormalities in cystic fibrosis: etiology, clinical implications and response to therapeutic interventions. J Cyst Fibros 2017; 16 (05) 538-552
- 3 Flume PA, Robinson KA, O'Sullivan BP. et al; Clinical Practice Guidelines for Pulmonary Therapies Committee. Cystic fibrosis pulmonary guidelines: airway clearance therapies. Respir Care 2009; 54 (04) 522-537
- 4 Button BM, Wilson C, Dentice R. et al. Physiotherapy for cystic fibrosis in Australia and New Zealand: a clinical practice guideline. Respirology 2016; 21 (04) 656-667
- 5 Reid DW, Blizzard CL, Shugg DM, Flowers C, Cash C, Greville HM. Changes in cystic fibrosis mortality in Australia, 1979-2005. Med J Aust 2011; 195 (07) 392-395
- 6 Cystic Fibrosis Foundation. Cystic Fibrosis Foundation Patient Registry 2019 Annual Data Report. 2020. Accessed September 27, 2022 at: https://www.cff.org/media/23476/download
- 7 Rand S, Prasad SA. Exercise as part of a cystic fibrosis therapeutic routine. Expert Rev Respir Med 2012; 6 (03) 341-351 , quiz 352
- 8 Matthews LW, Doershuk CF, Wise M, Eddy G, Nudelman H, Spector S. A therapeutic regimen for patients with cystic fibrosis. J Pediatr 1964; 65 (04) 558-575
- 9 Nixon PA, Orenstein DM, Kelsey SF, Doershuk CF. The prognostic value of exercise testing in patients with cystic fibrosis. N Engl J Med 1992; 327 (25) 1785-1788
- 10 Hebestreit H, Hulzebos EHJ, Schneiderman JE. et al; Prognostic Value of CPET in CF Study Group. Cardiopulmonary exercise testing provides additional prognostic information in cystic fibrosis. Am J Respir Crit Care Med 2019; 199 (08) 987-995
- 11 Kampouras A, Hatziagorou E, Kalantzis T. et al. The fitter the better? Cardiopulmonary exercise testing can predict pulmonary exacerbations in cystic fibrosis. Children (Basel) 2021; 8 (06) 527
- 12 Caspersen CJ, Powell KE, Christenson GM. Physical activity, exercise, and physical fitness: definitions and distinctions for health-related research. Public Health Rep 1985; 100 (02) 126-131
- 13 Cox NS, Holland AE. Current perspectives of physical activity in cystic fibrosis. Expert Rev Respir Med 2019; 13 (01) 13-22
- 14 Schneiderman JE, Wilkes DL, Atenafu EG. et al. Longitudinal relationship between physical activity and lung health in patients with cystic fibrosis. Eur Respir J 2014; 43 (03) 817-823
- 15 Hebestreit H, Schmid K, Kieser S. et al. Quality of life is associated with physical activity and fitness in cystic fibrosis. BMC Pulm Med 2014; 14: 26
- 16 Savi D, Simmonds N, Di Paolo M. et al. Relationship between pulmonary exacerbations and daily physical activity in adults with cystic fibrosis. BMC Pulm Med 2015; 15: 151
- 17 Radtke T, Nevitt SJ, Hebestreit H, Kriemler S. Physical exercise training for cystic fibrosis. Cochrane Database Syst Rev 2017; 11: CD002768
- 18 Morrison L, Parrott H. Standards of Care and Good Clinical Practice for the Physiotherapy Management of Cystic Fibrosis. 4th ed.. London, United Kingdom: Cystic Fibrosis Trust; 2020
- 19 Swisher A, Hebestreit H, Meija-Downs A. et al. Exercise and habitual physical activity for people with cystic fibrosis: expert consensus, evidence-based guide for advising patients. Cardiopulm Phys Ther J 2015; 26: 85-98
- 20 Matsuo T, Saotome K, Seino S. et al. Effects of a low-volume aerobic-type interval exercise on VO2max and cardiac mass. Med Sci Sports Exerc 2014; 46 (01) 42-50
- 21 Ito S. Rationale and optimising of outcomes in high-intensity interval training for health and disease. J Phys Fit Sports Med 2021; 10 (03) 151-164
- 22 Sawyer A, Cavalheri V, Jenkins S. et al. High-intensity interval training is effective at increasing exercise endurance capacity and is well tolerated by adults with cystic fibrosis. J Clin Med 2020; 9 (10) 3098
- 23 Gruber W, Orenstein DM, Braumann KM, Beneke R. Interval exercise training in cystic fibrosis—effects on exercise capacity in severely affected adults. J Cyst Fibros 2014; 13 (01) 86-91
- 24 Curran M, Tierney AC, Button B. et al. The effectiveness of exercise interventions to increase physical activity in cystic fibrosis: a systematic review. J Cyst Fibros 2022; 21 (02) 272-281
- 25 Hebestreit H, Kriemler S, Schindler C. et al; ACTIVATE-CF Study Working Group. Effects of a partially supervised conditioning program in cystic fibrosis: an international multicenter, randomized controlled trial (ACTIVATE-CF). Am J Respir Crit Care Med 2022; 205 (03) 330-339
- 26 Beaudoin N, Bouvet GF, Coriati A, Rabasa-Lhoret R, Berthiaume Y. Combined exercise training improves glycemic control in adult with cystic fibrosis. Med Sci Sports Exerc 2017; 49 (02) 231-237
- 27 Gupta S, Mukherjee A, Lodha R. et al. Effects of exercise intervention program on bone mineral accretion in children and adolescents with cystic fibrosis: a randomized controlled trial. Indian J Pediatr 2019; 86 (11) 987-994
- 28 Poore TS, Taylor-Cousar JL, Zemanick ET. Cardiovascular complications in cystic fibrosis: a review of the literature. J Cyst Fibros 2022; 21 (01) 18-25
- 29 Gabel ME, Fox CK, Grimes RA. et al. Overweight and cystic fibrosis: An unexpected challenge. Pediatr Pulmonol 2022; 57 (Suppl. 01) S40-S49
- 30 Bell SC, Mall MA, Gutierrez H. et al. The future of cystic fibrosis care: a global perspective. Lancet Respir Med 2020; 8 (01) 65-124
- 31 Cox NS, Alison JA, Holland AE. Interventions for promoting physical activity in people with cystic fibrosis. Cochrane Database Syst Rev 2013; 12 (12) CD009448
- 32 Layton AM, Irwin AM, Mihalik EC. et al. Telerehabilitation using fitness application in patients with severe cystic fibrosis awaiting lung transplant: a pilot study. Int J Telemed Appl 2021; 2021: 6641853
- 33 Holmes CJ, Racette SB, Symonds L, Arbeláez AM, Cao C, Granados A. Feasibility and efficacy of telehealth-based resistance exercise training in adolescents with cystic fibrosis and glucose intolerance. Int J Environ Res Public Health 2022; 19 (06) 3297
- 34 Hillen B, Simon P, Schlotter S. et al. Feasibility and implementation of a personalized, web-based exercise intervention for people with cystic fibrosis for 1 year. BMC Sports Sci Med Rehabil 2021; 13 (01) 95
- 35 Cox N, Eldridge B, Rawlings S. et al. Web-based physical activity promotion in CF: A clinical trial. Respirology 2022; 27 (S1): 76-77
- 36 Hurley N, Moyna NM, Kehoe B, McCaffrey N, Redmond K, Hardcastle SJ. Factors influencing physical activity in adults with cystic fibrosis. BMC Pulm Med 2021; 21 (01) 113
- 37 Gruet M, Saynor ZL, Urquhart DS, Radtke T. Rethinking physical exercise training in the modern era of cystic fibrosis: a step towards optimising short-term efficacy and long-term engagement. J Cyst Fibros 2022; 21 (02) e83-e98
- 38 Hebestreit H, Arets HG, Aurora P. et al; European Cystic Fibrosis Exercise Working Group. Statement on exercise testing in cystic fibrosis. Respiration 2015; 90 (04) 332-351
- 39 Sawyer A, Cavalheri V, Wood J, Hill K. Exercise testing and exercise training within cystic fibrosis centres across Australia and New Zealand: what is considered important and what is current practice?. Intern Med J 2020; 50 (09) 1091-1099
- 40 Holland AE, Spruit MA, Troosters T. et al. An official European Respiratory Society/American Thoracic Society technical standard: field walking tests in chronic respiratory disease. Eur Respir J 2014; 44 (06) 1428-1446
- 41 Holland AE, Spruit MA, Singh SJ. How to carry out a field walking test in chronic respiratory disease. Breathe (Sheff) 2015; 11 (02) 128-139
- 42 Leite LR, Queiroz KCV, da Silva FH, Coelho CC, Donadio MVF, Aquino EDS. Clinical use of the modified shuttle test in children with cystic fibrosis: is one test sufficient?. Pediatr Pulmonol 2021; 56 (06) 1550-1557
- 43 Ramos KJ, Smith PJ, McKone EF. et al; CF Lung Transplant Referral Guidelines Committee. Lung transplant referral for individuals with cystic fibrosis: Cystic Fibrosis Foundation consensus guidelines. J Cyst Fibros 2019; 18 (03) 321-333
- 44 Leard LE, Holm AM, Valapour M. et al. Consensus document for the selection of lung transplant candidates: An update from the International Society for Heart and Lung Transplantation. J Heart Lung Transplant 2021; 40 (11) 1349-1379
- 45 Chetta A, Pisi G, Zanini A. et al. Six-minute walking test in cystic fibrosis adults with mild to moderate lung disease: comparison to healthy subjects. Respir Med 2001; 95 (12) 986-991
- 46 Saglam M, Vardar-Yagli N, Savci S. et al. Six minute walk test versus incremental shuttle walk test in cystic fibrosis. Pediatr Int 2016; 58 (09) 887-893
- 47 Strassmann A, Steurer-Stey C, Lana KD. et al. Population-based reference values for the 1-min sit-to-stand test. Int J Public Health 2013; 58 (06) 949-953
- 48 Haile SR, Fühner T, Granacher U, Stocker J, Radtke T, Kriemler S. Reference values and validation of the 1-minute sit-to-stand test in healthy 5-16-year-old youth: a cross-sectional study. BMJ Open 2021; 11 (05) e049143
- 49 Combret Y, Boujibar F, Gennari C. et al. Measurement properties of the one-minute sit-to-stand test in children and adolescents with cystic fibrosis: a multicenter randomized cross-over trial. PLoS One 2021; 16 (02) e0246781
- 50 Radtke T, Hebestreit H, Puhan MA, Kriemler S. The 1-min sit-to-stand test in cystic fibrosis—insights into cardiorespiratory responses. J Cyst Fibros 2017; 16 (06) 744-751
- 51 Gruet M, Peyré-Tartaruga LA, Mely L, Vallier JM. The 1-minute sit-to-stand test in adults with cystic fibrosis: correlations with cardipulmonary exercise test, 6-minute walk test and quadriceps strength. Respir Care 2016; 61 (12) 1620-1628
- 52 Balfour-Lynn IM, Prasad SA, Laverty A, Whitehead BF, Dinwiddie R. A step in the right direction: assessing exercise tolerance in cystic fibrosis. Pediatr Pulmonol 1998; 25 (04) 278-284
- 53 Holland AE, Rasekaba T, Wilson JW, Button BM. Desaturation during the 3-minute step test predicts impaired 12-month outcomes in adult patients with cystic fibrosis. Respir Care 2011; 56 (08) 1137-1142
- 54 Narang I, Pike S, Rosenthal M, Balfour-Lynn IM, Bush A. Three-minute step test to assess exercise capacity in children with cystic fibrosis with mild lung disease. Pediatr Pulmonol 2003; 35 (02) 108-113
- 55 Wilson LM, Ellis MJ, Lane RL. et al. Development of the A-STEP: a new incremental maximal exercise capacity step test in cystic fibrosis. Pediatr Pulmonol 2021; 56 (12) 3777-3784
- 56 Boucher RC. Muco-obstructive lung diseases. N Engl J Med 2019; 380 (20) 1941-1953
- 57 Ratjen FA. Cystic fibrosis: pathogenesis and future treatment strategies. Respir Care 2009; 54 (05) 595-605
- 58 O'Sullivan BP, Freedman SD. Cystic fibrosis. Lancet 2009; 373 (9678): 1891-1904
- 59 McIlwaine M, Bradley J, Elborn JS, Moran F. Personalising airway clearance in chronic lung disease. Eur Respir Rev 2017; 26 (143) 160086
- 60 Menkes H, Lindsay D, Wood L, Muir A, Macklem PT. Interdependence of lung units in intact dog lungs. J Appl Physiol 1972; 32 (05) 681-686
- 61 Zidulka A, Sylvester JT, Nadler S, Anthonisen NR. Lung interdependence and lung-chest wall interaction of sublobar and lobar units in pigs. J Appl Physiol 1979; 46 (01) 8-13
- 62 Martin HB. Respiratory bronchioles as the pathway for collateral ventilation. J Appl Physiol 1966; 21 (05) 1443-1447
- 63 Macklem PT. Airway obstruction and collateral ventilation. Physiol Rev 1971; 51 (02) 368-436
- 64 Falk M, Kelstrup M, Andersen JB. et al. Improving the ketchup bottle method with positive expiratory pressure, PEP, in cystic fibrosis. Eur J Respir Dis 1984; 65 (06) 423-432
- 65 Kim CS, Iglesias AJ, Sackner MA. Mucus clearance by two-phase gas-liquid flow mechanism: asymmetric periodic flow model. J Appl Physiol 1987; 62 (03) 959-971
- 66 McCarren B, Alison JA. Physiological effects of vibration in subjects with cystic fibrosis. Eur Respir J 2006; 27 (06) 1204-1209
- 67 McIllwaine M, Chivers M, Lee Son N, Richmond M. Analysis of expiratory flow rates used in autogenic drainage. Are they sufficiently high to mobilize secretions?. J Cyst Fibros 2014; 13 (Suppl. 02) S29
- 68 O'Sullivan KJ, Collins L, McGrath D, Linnane B, O'Sullivan L, Dunne CP. Oscillating positive expiratory pressure therapy may be performed poorly by children with cystic fibrosis. Respir Care 2019; 64 (04) 398-405
- 69 Hasani A, Pavia D, Agnew JE, Clarke SW. Regional lung clearance during cough and forced expiration technique (FET): effects of flow and viscoelasticity. Thorax 1994; 49 (06) 557-561
- 70 Rowbotham NJ, Daniels TE. Airway clearance and exercise for people with cystic fibrosis: balancing longevity with life. Pediatr Pulmonol 2022; 57 (Suppl. 01) S50-S59
- 71 International Physiotherapy Group for Cystic Fibrosis. Physiotherapy for people with cystic fibrosis: from infant to adult. 7th Edition. Accessed 1st May 2022 at: https://www.ecfs.eu/ipg_cf/booklet
- 72 Burnham P, Stanford G, Stewart R. Autogenic drainage for airway clearance in cystic fibrosis. Cochrane Database Syst Rev 2021; 12: CD009595
- 73 Main E, Prasad A, Schans C. Conventional chest physiotherapy compared to other airway clearance techniques for cystic fibrosis. Cochrane Database Syst Rev 2005; (01) CD002011
- 74 McIlwaine M, Button B, Nevitt SJ. Positive expiratory pressure physiotherapy for airway clearance in people with cystic fibrosis. Cochrane Database Syst Rev 2019; 2019 (11) CD003147
- 75 Mckoy NA, Wilson LM, Saldanha IJ, Odelola OA, Robinson KA. Active cycle of breathing technique for cystic fibrosis. Cochrane Database Syst Rev 2016; 7 (07) CD007862
- 76 Morrison L, Milroy S. Oscillating devices for airway clearance in people with cystic fibrosis. Cochrane Database Syst Rev 2020; 4 (04) CD006842
- 77 Warnock L, Gates A. Chest physiotherapy compared to no chest physiotherapy for cystic fibrosis. Cochrane Database Syst Rev 2015; (12) CD001401
- 78 McIlwaine MP, Alarie N, Davidson GF. et al. Long-term multicentre randomised controlled study of high frequency chest wall oscillation versus positive expiratory pressure mask in cystic fibrosis. Thorax 2013; 68 (08) 746-751
- 79 Cystic Fibrosis Canada. The Canadian Cystic Fibrosis Registry 2020 Annual Data report. Accessed March 19, 2022 at: https://www.cysticfibrosis.ca/Registry/2020AnnualDataReport.pdf
- 80 Cystic Fibrosis NZ. Port CF Data Registry, 2017 Registry Report. Accessed March 19, 2022 at: www.cfnz.org.nz/what-we-do/port-cf-data-registry
- 81 Cystic Fibrosis Trust. UK Cystic Fibrosis Registry 2020 Annual Data Report. Accessed March 19 2022 at: https://www.cysticfibrosis.org.uk/sites/default/files/2022-02/2020%20Annual%20data%20report%20-%20Version%202.pdf
- 82 Ward N, Stiller K, Holland AE. Australian Cystic Fibrosis Exercise Survey group. Exercise is commonly used as a substitute for traditional airway clearance techniques by adults with cystic fibrosis in Australia: a survey. J Physiother 2019; 65 (01) 43-50
- 83 Narayanan S, Mainz JG, Gala S, Tabori H, Grossoehme D. Adherence to therapies in cystic fibrosis: a targeted literature review. Expert Rev Respir Med 2017; 11 (02) 129-145
- 84 Gifford AH, Mayer-Hamblett N, Pearson K, Nichols DP. Answering the call to address cystic fibrosis treatment burden in the era of highly effective CFTR modulator therapy. J Cyst Fibros 2020; 19 (05) 762-767
- 85 Arias Llorente RP, Bousoño García C, Díaz Martín JJ. Treatment compliance in children and adults with cystic fibrosis. J Cyst Fibros 2008; 7 (05) 359-367
- 86 Myers LB, Horn SA. Adherence to chest physiotherapy in adults with cystic fibrosis. J Health Psychol 2006; 11 (06) 915-926
- 87 Zanni RL, Sembrano EU, Du DT, Marra B, Bantang R. The impact of re-education of airway clearance techniques (REACT) on adherence and pulmonary function in patients with cystic fibrosis. BMJ Qual Saf 2014; 23 (Suppl. 01) i50-i55
- 88 Dixon E, Puckey M, Collins N, Marsh G, Pabary R. Striving for perfection, accepting the reality: a reflection on adherence to airway clearance and inhalation therapy for paediatric patients with chronic suppurative lung disease. Paediatr Respir Rev 2020; 34: 46-52
- 89 Calthorpe RJ, Smith SJ, Rowbotham NJ. et al. What effective ways of motivation, support and technologies help people with cystic fibrosis improve and sustain adherence to treatment?. BMJ Open Respir Res 2020; 7 (01) e000601
- 90 Nicolais CJ, Bernstein R, Saez-Flores E, McLean KA, Riekert KA, Quittner AL. Identifying factors that facilitate treatment adherence in cystic fibrosis: qualitative analyses of interviews with parents and adolescents. J Clin Psychol Med Settings 2019; 26 (04) 530-540
- 91 Zach MS, Purrer B, Oberwaldner B. Effect of swimming on forced expiration and sputum clearance in cystic fibrosis. Lancet 1981; 2 (8257): 1201-1203
- 92 Zach M, Oberwaldner B, Häusler F. Cystic fibrosis: physical exercise versus chest physiotherapy. Arch Dis Child 1982; 57 (08) 587-589
- 93 Salh W, Bilton D, Dodd M, Webb AK. Effect of exercise and physiotherapy in aiding sputum expectoration in adults with cystic fibrosis. Thorax 1989; 44 (12) 1006-1008
- 94 Dwyer TJ, Zainuldin R, Daviskas E, Bye PT, Alison JA. Effects of treadmill exercise versus Flutter on respiratory flow and sputum properties in adults with cystic fibrosis: a randomised, controlled, cross-over trial. BMC Pulm Med 2017; 17 (01) 14
- 95 Dwyer TJ, Alison JA, McKeough ZJ, Daviskas E, Bye PTP. Effects of exercise on respiratory flow and sputum properties in patients with cystic fibrosis. Chest 2011; 139 (04) 870-877
- 96 Hebestreit A, Kersting U, Basler B, Jeschke R, Hebestreit H. Exercise inhibits epithelial sodium channels in patients with cystic fibrosis. Am J Respir Crit Care Med 2001; 164 (03) 443-446
- 97 Schmitt L, Wiebel M, Frese F. et al. Exercise reduces airway sodium ion reabsorption in cystic fibrosis but not in exercise asthma. Eur Respir J 2011; 37 (02) 342-348
- 98 Dwyer TJ, Daviskas E, Zainuldin R. et al. Effects of exercise and airway clearance (positive expiratory pressure) on mucus clearance in cystic fibrosis: a randomised crossover trial. Eur Respir J 2019; 53 (04) 1801793
- 99 Lannefors L, Wollmer P. Mucus clearance with three chest physiotherapy regimes in cystic fibrosis: a comparison between postural drainage, PEP and physical exercise. Eur Respir J 1992; 5 (06) 748-753
- 100 Ward N, Morrow S, Stiller K, Holland AE. Exercise as a substitute for traditional airway clearance in cystic fibrosis: a systematic review. Thorax 2020; 76 (08) 763-771
- 101 Rowbotham NJ, Smith SJ, Davies G. et al. Can exercise replace airway clearance techniques in cystic fibrosis? A survey of patients and healthcare professionals. J Cyst Fibros 2020; 19 (04) e19-e24
- 102 Rowbotham NJ, Smith S, Leighton PA. et al. The top 10 research priorities in cystic fibrosis developed by a partnership between people with CF and healthcare providers. Thorax 2018; 73 (04) 388-390
- 103 Heijerman HGM, McKone EF, Downey DG. et al; VX17-445-103 Trial Group. Efficacy and safety of the elexacaftor plus tezacaftor plus ivacaftor combination regimen in people with cystic fibrosis homozygous for the F508del mutation: a double-blind, randomised, phase 3 trial. Lancet 2019; 394 (10212): 1940-1948
- 104 Middleton PG, Mall MA, Dřevínek P. et al; VX17-445-102 Study Group. Elexacaftor-tezacaftor-ivacaftor for cystic fibrosis with a single Phe508del allele. N Engl J Med 2019; 381 (19) 1809-1819
- 105 Ramsey BW, Davies J, McElvaney NG. et al; VX08-770-102 Study Group. A CFTR potentiator in patients with cystic fibrosis and the G551D mutation. N Engl J Med 2011; 365 (18) 1663-1672
- 106 Edgeworth D, Keating D, Ellis M. et al. Improvement in exercise duration, lung function and well-being in G551D-cystic fibrosis patients: a double-blind, placebo-controlled, randomized, cross-over study with ivacaftor treatment. Clin Sci (Lond) 2017; 131 (15) 2037-2045
- 107 Quon BS, Ramsook AH, Dhillon SS. et al. Short-term effects of Lumacaftor/Ivacaftor (Orkambi) on exertional symptoms, exercise performance, and ventilatory responses in adults with cystic fibrosis. Respir Res 2020; 21 (01) 135
- 108 Wilson J, You X, Ellis M. et al. VO2max as an exercise tolerance endpoint in people with cystic fibrosis: lessons from a lumacaftor/ivacaftor trial. J Cyst Fibros 2021; 20 (03) 499-505
- 109 Bailey J, Rozga M, McDonald CM. et al. Effect of CFTR modulators on anthropometric parameters in individuals with cystic fibrosis: an evidence analysis center systematic review. J Acad Nutr Diet 2021; 121 (07) 1364-1378.e2
- 110 King SJ, Tierney AC, Edgeworth D. et al. Body composition and weight changes after ivacaftor treatment in adults with cystic fibrosis carrying the G551 D cystic fibrosis transmembrane conductance regulator mutation: a double-blind, placebo-controlled, randomized, crossover study with open-label extension. Nutrition 2021; 85: 111124
- 111 Mayer-Hamblett N, Nichols DP, Odem-Davis K. et al. Evaluating the impact of stopping chronic therapies after modulator drug therapy in cystic fibrosis. Ann Am Thorac Soc 2021; 18 (08) 1397-1405
- 112 Granger E, Davies G, Keogh RH. Treatment patterns in people with cystic fibrosis: have they changed since the introduction of ivacaftor?. J Cyst Fibros 2022; 21 (02) 316-322
- 113 ISRCTN. A randomised open-label trial to assess change in respiratory function for people with cystic fibrosis (pwCF) established on triple combination therapy (Kaftrio) after rationalisation of nebulised mucoactive therapies (the CF STORM trial). Accessed March 25, 2022 at: https://doi.org/10.1186/ISRCTN14081521
- 114 Wucherpfennig L, Triphan SMF, Wege S. et al. Magnetic resonance imaging detects improvements of pulmonary and paranasal sinus abnormalities in response to elexacaftor/tezacaftor/ivacaftor therapy in adults with cystic fibrosis. J Cyst Fibros 2022; (e-pub ahead of print) DOI: 10.1016/j.jcf.2022.03.011.
- 115 Donaldson SH, Laube BL, Mogayzel P. et al. Effect of lumacaftor-ivacaftor on mucociliary clearance and clinical outcomes in cystic fibrosis: results from the PROSPECT MCC sub-study. J Cyst Fibros 2022; 21 (01) 143-145