World No Tobacco day- Smoking and COVID-19; A dangerous combination

By Dr Rahul Bahot

The World Health Organisation states approximately 1.1 billion people smoke daily. Tobacco smoke is a mixture of particles which act as toxins and carcinogens in the human body. Smoking cigarettes accounts for 6.3 million annual deaths worldwide and 6.3% global burden of the diseases. Smoking , (1st, 2nd and 3rd hand smoke) increases the risk of upper and lower respiratory tract infection. It also increases the risk of viral infections by causing structural changes in the epithelium and impairing the mucus clearance mechanism causing epithelial barrier dysfunction and fibrosis.

Mechanism of action of smoking

Smoking increases expression of Angiotensin II Receptors, which are necessary for the Covid 19 virus to gain entry into the cell and cause the disease. Thus, smoking facilitates the entry of Covid 19 virus in the human body.

Cigarette smoke reduces inflammation in the lung , which results in the release of pro-inflammatory cytokines and tumour necrosis factor alpha. It also increases mucus production and impairs muco-ciliary clearance in the respiratory tract. Thus, contributing to the “cytokine storm” which is a result of excessive production of pro-inflammatory cytokines.

Influence of cigarette smoking on COVID 19

The coronavirus disease 2019, originated from Wuhan city in China. Now Covid-19, primarily affects the respiratory system. A retrospective analysis of 78 patients infected with Covid 19 from Wuhan reported rapid and more fulminant clinical worsening in people who smoked as compared to non-smokers (27% versus 3%).

The results of various meta-analyses of studies, signifying the effect of smoking are controversial. Some meta-analyses concluded that there is no relationship between smoking and stability of Covid-19 while some researchers in their meta-analysis have found a significant relationship between smoking and the severity of infection.

Influence of E-cigarettes and Hookah on COVID 19

Vaping is shown to have a more disastrous effect on health as compared to direct cigarette smoking. Similarly, the design of hookah having a cold water reservoir with a complex cleaning mechanism makes it an ideal vector for transmission of Covid 19. The hookah bars present in the city facilitate multiple users using the same hookah smoking, thereby increasing the transmission of Covid 19 within the city.

Finally:

One cannot undermine the harmful effects of smoking though the results of the studies are controversial. The results depend upon the type of the population and the timeframe along with primary objectives of the study. Overall smoking causes damage to the lung architecture and causes diseases affecting the cardiovascular system, digestive system, and the reproductive system. Hence, smoking is harmful for the body and in all probability to be avoided.

(The author is Consultant Respiratory Medicine and Pulmonologist, Jaslok Hospital and Research Centre. The article is for informational purposes only. Please consult experts and medical professionals before starting any therapy or medication. Views expressed are personal and do not reflect the official position or policy of the Financial Express Online.)