Chronic Obstructive Pulmonary Disease (COPD)

    Written by:
    Marina Shkayeva

    Fact-checked

    by:

    Morgan Pfiffner, Shyam Jayaraman
    Last Updated: January 22, 2025

    Chronic obstructive pulmonary disease (COPD) is a chronic disease of the lungs that involves airway damage and blockage that worsens over time. The progressively worsening airway blockage causes the main symptoms of COPD: difficulty breathing, cough, and mucus production. While the most common cause of COPD is smoking, other causes can include significant exposure to air pollutants, frequent respiratory infections, and untreated asthma. Standard COPD treatments include use of specific inhalers to relax and open up the airways.

    17 references on this page
    15,681 participants in 15 trials and 12 meta-analyses

    Overview

    Examine Database: Chronic Obstructive Pulmonary Disease (COPD)

    Research FeedRead all studies

    Frequently asked questions

    Examine Database References

    1. Weight - Fuld JP, Kilduff LP, Neder JA, Pitsiladis Y, Lean ME, Ward SA, Cotton MMCreatine supplementation during pulmonary rehabilitation in chronic obstructive pulmonary diseaseThorax.(2005 Jul)
    2. Weight - Deacon SJ, Vincent EE, Greenhaff PL, Fox J, Steiner MC, Singh SJ, Morgan MDRandomized controlled trial of dietary creatine as an adjunct therapy to physical training in chronic obstructive pulmonary diseaseAm J Respir Crit Care Med.(2008 Aug 1)
    3. COPD Symptoms - Faager G, Söderlund K, Sköld CM, Rundgren S, Tollbäck A, Jakobsson PCreatine supplementation and physical training in patients with COPD: a double blind, placebo-controlled studyInt J Chron Obstruct Pulmon Dis.(2006)
    4. Exercise Capacity (with Heart Conditions) - Al-Ghimlas F, Todd DCCreatine supplementation for patients with COPD receiving pulmonary rehabilitation: a systematic review and meta-analysisRespirology.(2010 Jul)
    5. Weight - Funamoto M, Sunagawa Y, Katanasaka Y, Miyazaki Y, Imaizumi A, Kakeya H, Yamakage H, Satoh-Asahara N, Komiyama M, Wada H, Hasegawa K, Morimoto THighly absorptive curcumin reduces serum atherosclerotic low-density lipoprotein levels in patients with mild COPDInt J Chron Obstruct Pulmon Dis.(2016 Aug 26)
    6. Weight - A Borghi-Silva, V Baldissera, L M M Sampaio, V A Pires-DiLorenzo, M Jamami, A Demonte, J S Marchini, D CostaL-carnitine as an ergogenic aid for patients with chronic obstructive pulmonary disease submitted to whole-body and respiratory muscle training programsBraz J Med Biol Res.(2006 Apr)
    7. COPD Symptoms - Decramer M, Rutten-van Mölken M, Dekhuijzen PN, Troosters T, van Herwaarden C, Pellegrino R, van Schayck CP, Olivieri D, Del Donno M, De Backer W, Lankhorst I, Ardia AEffects of N-acetylcysteine on outcomes in chronic obstructive pulmonary disease (Bronchitis Randomized on NAC Cost-Utility Study, BRONCUS): a randomised placebo-controlled trialLancet.(2005 Apr 30-May 6)
    8. COPD Symptoms - De Benedetto F, Aceto A, Dragani B, Spacone A, Formisano S, Pela R, Donner CF, Sanguinetti CMLong-term oral n-acetylcysteine reduces exhaled hydrogen peroxide in stable COPDPulm Pharmacol Ther.(2005)
    9. COPD Symptoms - Peter N Black, Althea Morgan-Day, Tracey E McMillan, Phillippa J Poole and Robert P YoungRandomised, controlled trial of N-acetylcysteine for treatment of acute exacerbations of chronic obstructive pulmonary diseasePulmonary Medicine.()
    10. COPD Symptoms - Jiang C, Zou J, Lv Q, Yang YSystematic review and meta-analysis of the efficacy of N-acetylcysteine in the treatment of acute exacerbation of chronic obstructive pulmonary disease.Ann Palliat Med.(2021-Jun)
    11. COPD Symptoms - Huang C, Kuo S, Lin L, Yang YThe efficacy of -acetylcysteine in chronic obstructive pulmonary disease patients: a meta-analysis.Ther Adv Respir Dis.(2023)
    12. Neutrophil Activity - van Overveld FJ, Vermeire PA, De Backer WAInduced sputum of patients with chronic obstructive pulmonary disease (COPD) contains adhesion-promoting, therapy-sensitive factorsInflamm Res.(2000 Jan)
    13. Bronchitis Symptoms - Wei J, Pang CS, Han J, Yan HEffect of Orally Administered N-Acetylcysteine on Chronic Bronchitis: A Meta-analysis.Adv Ther.(2019-Dec)
    14. COPD Symptoms - Liang R, Liu D, Li H, Yan Y, Xie W, Zhai ZThe efficacy and safety of herbal formulas for adults with pulmonary hypertension combined with chronic obstructive pulmonary disease: a systematic review and meta-analysis involving 1,865 participants.J Thorac Dis.(2024 Sep 30)
    15. Blood Pressure - Alshafie S, El-Helw GO, Fayoud AM, Elrashedy AA, Gbreel MI, Alfayoumi SS, Mohamed IM, Abdelwadoud GT, Isa AS, Ragab KM, Nourelden AZEfficacy of dietary nitrate-rich beetroot juice supplementation in patients with chronic obstructive pulmonary disease (COPD): A systematic review and meta-analysis.Clin Nutr ESPEN.(2021 Apr)
    16. Blood Pressure - Yang H, He S, Chen F, Liang L, Pan JEfficacy and safety of nitrate supplementation on exercise tolerance in chronic obstructive pulmonary disease: A systematic review and meta-analysis.Medicine (Baltimore).(2022 Jan 14)
    17. Exercise Capacity - Wang J, Feng F, Zhao Y, Bai L, Xu Y, Wei Y, He H, Zhou XDietary nitrate supplementation to enhance exercise capacity in patients with COPD: Evidence from a meta-analysis of randomized controlled trials and a network pharmacological analysis.Respir Med.(2024-Feb)
    18. Vascular Function - Delacoste FBC, Goulart CDL, Guidoti AB, Türck P, Eibel B, Irigoyen MC, de Araujo CLP, Dal Lago PEvaluating the impact of short-term nitrate-rich dietary supplementation on endothelial function in COPD: A randomized crossover study.Respir Med.(2024 Oct)
    19. Uric Acid - Abdollahi S, Vajdi M, Meshkini F, Vasmehjani AA, Sangsefidi ZS, Clark CCT, Soltani SResveratrol may mildly improve renal function in the general adult population: A systematic review and meta-analysis of randomized controlled clinical trials.Nutr Res.(2023-May)
    20. C-Reactive Protein (CRP) - Armita Mahdavi Gorabi, Saeed Aslani, Danyal Imani, Bahman Razi, Thozhukat Sathyapalan, Amirhossein SahebkarEffect of resveratrol on C-reactive protein: An updated meta-analysis of randomized controlled trialsPhytother Res.(2021 Dec)
    21. Exercise Capacity (with Heart Conditions) - Marwood S, Jack S, Patel M, Walker P, Bowtell J, Calverley PNo effect of glutamine ingestion on indices of oxidative metabolism in stable COPDRespir Physiol Neurobiol.(2011 Jun 30)
    22. Lung Function - Pletcher MJ, Vittinghoff E, Kalhan R, Richman J, Safford M, Sidney S, Lin F, Kertesz SAssociation between marijuana exposure and pulmonary function over 20 yearsJAMA.(2012 Jan 11)
    23. Lung Function - Yu H, Lei T, Su X, Zhang L, Feng Z, Dong M, Hou Z, Guo H, Liu JEfficacy and safety of three species of L. in patients with chronic obstructive pulmonary disease: A systematic review and meta-analysis.Front Pharmacol.(2023)
    24. C-Reactive Protein (CRP) - Yu H, Su X, Lei T, Zhang C, Zhang M, Wang Y, Zhu L, Liu JEffect of Omega-3 Fatty Acids on Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.Int J Chron Obstruct Pulmon Dis.(2021 Sep 23)
    25. Exercise Tolerance - Kikuchi H, Shiozawa N, Takata S, Ashida K, Mitsunobu FEffect of repeated Waon therapy on exercise tolerance and pulmonary function in patients with chronic obstructive pulmonary disease: a pilot controlled clinical trial.Int J Chron Obstruct Pulmon Dis.(2014)
    26. Cathelicidin - Sanders EC, Burkes RM, Mock JR, Brown TT, Wise RA, Hansel NN, Liu MC, Drummond MBBronchoalveolar Lavage and Plasma Cathelicidin Response to 25-Hydroxy Vitamin D Supplementation: A Pilot Study.Chronic Obstr Pulm Dis.(2021-Jul-28)
    27. Interleukin 8 - Norheim KL, Ben Ezra M, Heckenbach I, Andreasson LM, Eriksen LL, Dyhre-Petersen N, Damgaard MV, Berglind M, Pricolo L, Sampson D, Dellinger RW, Sverrild A, Treebak JT, Ditlev SB, Porsbjerg C, Scheibye-Knudsen MEffect of nicotinamide riboside on airway inflammation in COPD: a randomized, placebo-controlled trial.Nat Aging.(2024 Dec)