A new study, published in the American Journal of Preventive Medicine, has revealed that using e-cigarette could increase the risk of developing chronic lung diseases such as asthma, bronchitis, emphysema or chronic obstructive pulmonary disease.
As per the study, people, who use e-cigarettes as well as smoke tobacco, are at a higher risk of developing chronic lung disease than those who use either product alone.
Tracking e-cigarette and tobacco habits
Stanton Glantz, PhD, Professor at the University of California in the US, said: "What we found is that for e-cigarette users, the odds of developing lung disease increased by about a third, even after controlling for their tobacco use and their clinical and demographic information."
"We concluded that e-cigarettes are harmful on their own, and the effects are independent of smoking conventional tobacco," the senior study author said.
The research is based on an analysis of publicly available data from the Population Assessment of Tobacco and Health (PATH). The data tracked e-cigarette and tobacco habits as well as new lung disease diagnoses in over 32,000 American adults from 2013 to 2016.
Several earlier population studies had linked e-cigarette use and lung disease at a single point in time. But those cross-sectional studies made it very difficult for the researchers to understand if lung disease was being caused by the use of e-cigarettes or whether people with lung disease were more likely to use them.
Study based on people who did not have lung diseases
This latest study followed people, who did not have any lung disease, for three years and to an entire account of their e-cigarette use and smoking from the beginning. This provided the researchers to get stronger evidence of an association between adult e-cigarette use and lung diseases than the previous studies.
The study revealed that those who smoke tobacco have an increased rate of risk by 2.6%, while those who use e-cigarette, both former and present users, were 1.3 times more likely to develop chronic lung disease. Glantz said, "Dual users -- the most common use pattern among people who use e-cigarettes — get the combined risk of e-cigarettes and conventional cigarettes, so they're actually worse off than tobacco smokers."
The researchers also found that people who switched from smoking to using e-cigarettes have a lower risk of developing lung disease. However, the study said that less than one percent of the smokers had completely switched to e-cigarettes.
EVALI (E-cigarette or Vaping Product Use-Associated Lung Injury)
Meanwhile, the findings of this study are not related to EVALI (E-cigarette or Vaping Product Use-Associated Lung Injury) that was first reported last summer. Many e-cigarette users, who suffered from this acute lung disease lost their lives and some were admitted in the hospital.
The chemical analysis of e-cigarettes showed that they contain higher levels of certain toxic chemicals than conventional cigarettes. Several previous physiological studies in both animals and humans found that e-cigarettes tend to suppress the immune system and increase the levels of stress-related proteins in the lungs. However, scientists are still trying to determine the exact cause of EVALI.
The new study has noted that e-cigarettes probably have several other health threats which may be extremely harmful for the users. "This study contributes to the growing case that e-cigarettes have long-term adverse effects on health and are making the tobacco epidemic worse," Glantz said.