Viny Kantroo  ( Department of Respiratory, Critical Care and Sleep Medicine, Indraprastha Apollo Hospitals, Sarita Vihar, New Delhi, India )
Atulya Atreja  ( Department of Pulmonology and Critical Care, Aaorogyam Hospital, Karnal. )
Saptarshi Bhattacharya  ( Department of Endocrinology, Indraprastha Apollo Hospitals, Sarita Vihar, Delhi, India )
Shehla Shaikh  ( Department of Endocrinology, Saifee Hospital, Mumbai. )
Sanjay Kalra,  ( Department of Endocrinology, Bharti Hospital, Karnal, )

The coronavirus disease 2019 (COVID-19) pandemic drew our attention to the interplay between pulmonary health and diabetes. The impact of poorly controlled diabetes in worsening COVID-19 outcome is well-recognized. This article explores the broad spectrum of associations between the lung and diabetes. The lung can be the target of organ damage in diabetes, be the origin of a disease process affecting glycaemic status, and also contribute to metabolic complications. Diabetes can be a part of several pulmonary syndromes. Medications used for diabetes can adversely affect the lungs and vice versa. On the other hand, certain glucose-lowering drugs have the potential to improve respiratory function. The close link between diabetes and lung disease calls for a combined approach to managing these conditions.

 

Keywords: Asthma, chronic obstructive pulmonary disease, diabetes, lung cancer, tuberculosis, pneumonia, obstructive sleep apnoea.

 

DOI: 10.47391/JPMA.03-23

 

Introduction

 

The lungs are the largest viscera of the human body and perform the essential function of gaseous exchange. Modern diabetes care discourse focuses on the cardio-vascular and viscero-metabolic aspects of health. It has further evolved to acknowledge the connection between non-alcoholic fatty liver disease (NAFLD) and dementia with diabetes and metabolic status. The coronavirus disease 2019 (COVID-19) pandemic underscored the close association between the control of diabetes and the clinical outcome of COVID-19.1,2 However, adequate emphasis has not been laid on the relationship between diabetes and pulmonary physiology, pathology, management, and prognosis in clinical practice. In this article, we have summarized the broad spectrum of manifestations under the ambit of “diabetic lung”  in Table and suggested ways to optimize its management.

 

The Diabetes Lung

 

Lung function and lung structure are both affected by long-standing diabetes. These dysfunctions can involve changes in the para-pulmonary structures, e.g., upper respiratory tract, chest musculature, and ribcage and manifest with varied respiratory symptoms, including cough and breathlessness.

Persons with diabetes are more prone to lung infections and experience worse outcomes than normoglycaemic individuals. Lung diseases like tuberculosis, pneumonia and fungal infections are more common in diabetes.3 Diabetes can precipitate or worsen other respiratory illnesses such as asthma and chronic obstructive pulmonary disease (COPD).4

Some causative factors, such as air pollution and tobacco usage, contribute to the pathophysiology of both lung disease and diabetes. There is also a higher prevalence of diabetes among individuals with asthma, COPD, and idiopathic pulmonary fibrosis.5 At times, the two conditions can confound each other. Occult pulmonary infection can cause poorly controlled diabetes, and undiagnosed diabetes can be a reason behind the refractoriness of pulmonary disease.6

Obstructive sleep apnoea (OSA), characterized by periods of apnoea and hypopnoea during sleep, is the prototype respiratory disease strongly linked to various metabolic disorders, including diabetes.7 Though treatment with continuous positive airway pressure (CPAP) fails to show improvement in glycaemic status in diabetes, institution of CPAP improves insulin resistance and prevents progression of prediabetes to diabetes.8

One should be aware of the role of pharmacologic agents in glucometabolic and pulmonary health. Respiratory drugs such as corticosteroids and beta agonists may lead to dysglycaemia, while medications like pioglitazone and renin-angiotensin-aldosterone-system blockers may cause respiratory symptoms.9 It must also be noted that glucagon-like peptide 1 receptor agonists and sodium glucose transporter 2 inhibitors (SGLT2i) are being “exapted” for use in OSA.10

 

Thinking Out-Of-The-Box

 

The syndrome ‘diabetic lung’ can present with multiple clinical permutations and combinations. The treating doctor must remain pulmovigilant while managing diabetes, and glucovigilant during treatment of pulmonary disease. Both diabetes and pulmonary disease are chronic conditions, characterized by acute-on-chronic exacerbations, and interconnected by a strong link with psychosocial and environmental factors. Both need significant amount of self-care and self-management. The concepts of glycaemic hygiene and respiratory hygiene are similar, and so are the techniques used to enhance patient awareness, education and motivation. The close interplay between the two systems reinforce the need to view diabetic lung as a distinct identity, and manage it holistically through teamwork.

 

References

 

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2.      Kantroo V, Kanwar MS, Goyal P, Rosha D, Modi N, Bansal A, et al. Mortality and Clinical Outcomes among Patients with COVID-19 and Diabetes. Med Sci. 2021;9:65. doi:10.3390/medsci9040065

3.      Klekotka RB, Mizgała E, Król W. The etiology of lower respiratory tract infections in people with diabetes. Pneumonol Alergol Pol. 2015;83:401-408. doi:10.5603/PiAP.2015.0065

4.      Kolahian S, Leiss V, Nürnberg B. Diabetic lung disease: fact or fiction? Rev Endocr Metab Disord. 2019;20:303-319. doi:10.1007/s11154-019-09516-w

5.      Khateeb J, Fuchs E, Khamaisi M. Diabetes and Lung Disease: A Neglected Relationship. Rev Diabet Stud RDS. 2019;15:1-15. doi:10.1900/RDS.2019.15.1

6.      Hua J, Huang P, Liao H, Lai X, Zheng X. Prevalence and Clinical Significance of Occult Pulmonary Infection in Elderly Patients with Type 2 Diabetes Mellitus. BioMed Res Int. 2021;2021:3187388. doi:10.1155/2021/3187388

7.      Bhattacharya S, Kantroo V, Atreja A, Kalra S. The Somno-Metabolic syndrome: Screening for obstructive sleep apnoea in metabolic syndrome. J Pak Med Assoc. 2022;72:2117-2118

8.      Iftikhar IH, Khan MF, Das A, Magalang UJ. Meta-analysis:continuous positive airway pressure improves insulin resistance in patients with sleep apnea without diabetes. Ann Am Thorac Soc.2013;10:115-120. doi:10.1513/AnnalsATS.201209-081OC

9.      Overlack A. ACE inhibitor-induced cough and bronchospasm.Incidence, mechanisms and management. Drug Saf. 1996;15:72- 78. doi:10.2165/00002018-199615010-00006

10.    Blackman A, Foster GD, Zammit G, et al. Effect of liraglutide 3.0 mg in individuals with obesity and moderate or severe obstructive sleep apnea: the SCALE Sleep Apnea randomized clinical trial. IntJ Obes 2005. 2016;40(8):1310-1319. doi:10.1038/ijo.2016.52