Study links e-cigarette use to increased respiratory symptoms

By Lily Ramsey, LLMReviewed by Lily Ramsey, LLMAug 2 2024

A recent study published in BMC Public Health investigated the association between electronic cigarette (EC) use and respiratory health in adults. They found that both short- and long-term use of EC elevated the risk of various respiratory symptoms.

Study: Vaping habits and respiratory symptoms using a smartphone app platform. Image Credit: bennphoto/Shutterstock.com

Background

The widespread use of mobile technology for healthcare and public health, especially during the COVID-19 pandemic, has enabled efficient participant recruitment and real-time data collection for epidemiological studies.

EC use, linked to severe lung illnesses and deaths in 2019, has raised concerns about toxic inhalation from toxic chemicals and microbial toxins in EC products.

Despite these concerns, there are limited epidemiological studies assessing the short- and long-term effects of vaping habits (using electronic devices to breathe “vapor”) on respiratory health.

The integration of smartphone application (app)-based approaches in epidemiologic research presents an opportunity to address this gap.

Therefore, researchers conducted a longitudinal, repeated measures study using a custom smartphone app to evaluate the potential impact of short- and long-term EC use on respiratory health in US adults.

About the study

In the present study, researchers developed a customized, downloadable smartphone app named “Vaping and Health Study (VHS)” to collect data on EC use and respiratory health. Participants above 21 years of age (legal age for tobacco purchase) who used a smartphone were recruited via social media and were required to complete a screening survey.

Further, a longitudinal app-based survey was conducted over 60 days, involving 306 participants. Notifications were sent via the app to remind participants.

About 73% of the participants completed the baseline survey, with 220 participants included in the final analysis after excluding those with missing data. The average age of the participants was 33.8 years. About 60.5% were non-Hispanic White, and 60% were female.

Respiratory symptoms were collected using a modified American Thoracic Society (ATS) questionnaire, covering symptoms like cough, wheeze, phlegm, shortness of breath, and eye and nose irritation.

Chronic cough and phlegm were defined as lasting more than three months, while shortness of breath was evaluated using the modified Medical Research Council (mMRC) dyspnea scale. EC habits were assessed by asking about ever use, as well as short-term (past day, week, month) and long-term (past 90 days) use.

Covariates, including age, sex, education, race/ethnicity, and smoking status, were assessed at baseline. Statistical analysis involved the use of the Pearson Chi-square test, Fisher’s exact test, generalized linear mixed models with random intercepts, and adjustments for covariates.

Results and discussion

At the baseline, 29.6% were found to be current smokers, 54.6% had used ECs, 29.1% were current EC users, and 45.5% had never used ECs.

Among the 220 participants, 14.1% had frequent cough, 12.7% had chronic cough, 15.5% had frequent phlegm, 16.8% had chronic phlegm, 12.3% had episodes of phlegm and cough lasting over three weeks annually.

Further, 21.4% of the participants had wheeze, 15.5% had wheezing attacks, 13.6% had severe-to-very severe dyspnea, 33.2% had chest cold, 43.6% had chest illnesses in the past three years, and 25.9% and 19.6% had eye and nose irritation, respectively.

Statistically significant differences were observed in frequent cough, wheeze, frequent phlegm, shortness of breath, and chest cold symptoms between EC users and non-users.

In the short-term analysis, EC use in the past week was found to be linked to higher odds of various respiratory symptoms, including frequent cough, chronic cough, frequent phlegm, chronic phlegm, episodes of cough and phlegm lasting over three weeks, severe dyspnea, chest cold, and eye and nose irritation.

On the other hand, long-term use over the past 90 days was associated with increased odds of wheeze, wheeze attacks, severe dyspnea, and eye irritation.

EC use in the past 30 days is also significantly associated with these symptoms. Sensitivity analyses confirmed the robustness of associations between short-term EC use and respiratory symptoms.

The study's strengths include its longitudinal app-based design for real-time data collection, effectively capturing both short- and long-term respiratory symptoms associated with EC use.

However, the study's limitations are potential self-reporting bias, limited generalizability due to volunteer recruitment, a modest sample size, possible uncontrolled confounding, lack of detailed user behavior data, and the potential for unrecognized effects of the coronavirus disease 2019 pandemic.

Conclusion

In conclusion, study links short-term and long-term EC use to a higher prevalence of various respiratory symptoms in adults.

The findings can potentially guide the development of effective public health and safety policies regarding vaping products.

While further research is necessary to confirm the findings, advancements in mobile technology will likely play a key role in evaluating the effects of vaping and monitoring the related health conditions.