Exploring the Long-term Cardiovascular Effects of Vaping (LIGER)

Exploring the Long-term Cardiovascular Effects of Vaping: a Longitudinal Study

Smoking is the "leading, preventable death-cause worldwide", being responsible for almost 700,000 deaths in the E.U. annually. Therefore, implementing successful, long-term smoking cessation strategies is a long-term priority for the NHS.

Recent evidence suggests that e-cigarettes (i.e., vaping) are a successful cessation tool, with around 3.6 million users in the UK. There are concerns about long-term vaping, particularly in relation to their cardiovascular effects, as there are no relevant, longitudinal studies.

Therefore, we propose a 38-month, four-group longitudinal study exploring the cardiovascular physiological effects of the use of e-cigarettes over a two-year period, informing policy makers and e-cigarette users (vapers). Our study was developed with the support of vapers.

The main research question is whether there are any differences in cardiovascular physiology between vapers, who are ex-smokers (Group A), vapers with no previous smoking experience (Group B), dual users (i.e., those who vape and smoke (Group C) and ex-smokers who don't vape (Group D).

Two-hundred participants from Sheffield and Leeds will be invited on five occasions (baseline, as well as 6-,12-,18- and 24-months post-baseline).

We will assess macrovascular and lung function, cardiovascular disease risk (through questionnaires and blood biomarkers), vaping and smoking dependence, smoking and and vaping history among others.

Study Overview

• Status: Active, not recruiting
• Conditions: Cardiovascular Diseases

• Study Type: Observational
• Enrollment (Estimated): 172

Contacts and Locations

Study Locations

• United Kingdom
  • Sheffield, United Kingdom, S10 2BP
    • Sheffield Hallam University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Vapers conforming to specific group criteria in wider Sheffield and Leeds areas, in the U.K.

Description

Inclusion Criteria:

• Inclusion Criteria: Age ≥18 years of either gender. Specific group inclusion criteria include:

Group A: Ex-smokers with previous smoking history of at least two years, who vape for at least one year, at least 50 puffs a day.

Group B: Current vapers who have been vaping daily (minimum 50 puffs/day) for at least one year, with no previous smoking history, Group C: Current vapers (50 puffs/day), who smoke at least 20 cigarettes per week. Group D: Ex-smokers, who have stopped smoking for a period greater than one year and who currently do not vape.

Exclusion Criteria:

• Non-ambulant people and people with a recent (e.g., within 6 months) CVD event (e.g. stroke, myocardial infarction) or cardiac surgery,
• pregnancy,
• people who require major surgery (which will prevent them of taking part in the study),
• people who are unable or unwilling to give informed consent.

Study Plan

How is the study designed?

Number of groups / cohorts

4

Cohorts and Interventions

Group / Cohort
Group A; vapers, who are ex-smokers.
Group B; vapers with no previous smoking experience.
Group C; vapers, who are dual users (i.e., those who vape and smoke).
Group D; ex-smokers who don't vape.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Brachial artery FMD using ultrasound	Baseline scanning to assess resting vessel diameter will be recorded over 3 min, following a 10-min resting period. The brachial artery will be imaged at a location 3 to 7 cm above the antecubital crease to create a flow stimulus in the brachial artery. The images will be obtained with a Viamo C100 (Canon Medical Systems Europe B.V., Zoetermeer, Netherlands) unit using a 7.5MHz PSI-30BX (Canon Medical Systems Europe B.V., Zoetermeer, Netherlands) transducer. A sphygmomanometric cuff will be placed on the forearm; the cuff will be inflated at least 50 mmHg above systolic pressure to occlude artery inflow for 5 min. Recordings will commence 30s before cuff deflation and continuing for 3 min after. FMD will be expressed as a change in post-stimulus diameter evaluated as a percentage of the baseline diameter.	24 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Brachial artery FMD using ultrasound	As in 24 months.	3 months
Brachial artery FMD using ultrasound	As in 24 months.	6 months
Brachial artery FMD using ultrasound	As in 24 months.	12 months
Brachial artery FMD using ultrasound	As in 24 months.	18 months
Vascular assessment of biomarkers	Venous blood samples (10 ml) will be obtained from the participants via a superficial arm vein to assess C-reactive protein, IL-12 (p70), sICAM-1, IL-8 and vWF.	24 months
Vascular assessment of biomarkers	Venous blood samples (10 ml) will be obtained from the participants via a superficial arm vein to assess C-reactive protein, IL-12 (p70), sICAM-1, IL-8 and vWF.	12 months
Vascular assessment of biomarkers	Venous blood samples (10 ml) will be obtained from the participants via a superficial arm vein to assess C-reactive protein, IL-12 (p70), sICAM-1, IL-8 and vWF.	6 months.
Vascular assessment of biomarkers	Venous blood samples (10 ml) will be obtained from the participants via a superficial arm vein to assess C-reactive protein, IL-12 (p70), sICAM-1, IL-8 and vWF.	18 months
Lung function	Lung function including FEV1, FVC and vital capacity will be measured according to international guidelines (ATS/ERS guidelines).	24 months
Lung function	Lung function including FEV1, FVC and vital capacity will be measured according to international guidelines (ATS/ERS guidelines).	6 months
Lung function	Lung function including FEV1, FVC and vital capacity will be measured according to international guidelines (ATS/ERS guidelines).	12 months
Lung function	Lung function including FEV1, FVC and vital capacity will be measured according to international guidelines (ATS/ERS guidelines).	18 months
Smoking dependence	Using Fagerström questionnaire.	baseline
Vaping dependence	Using Vaping dependence questionnaire.	baseline
Vaping dependence	Using Vaping dependence questionnaire.	6 months
Vaping dependence	Using Vaping dependence questionnaire.	12 months
Vaping dependence	Using Vaping dependence questionnaire.	18 months
Vaping dependence	Using Vaping dependence questionnaire.	24 months
Smoking dependence	Using Fagerström questionnaire.	24 months
Smoking dependence	Using Fagerström questionnaire.	18 months
Smoking dependence	Using Fagerström questionnaire.	12 months
Smoking dependence	Using Fagerström questionnaire.	6 months
Change in CV risk profile	Q-risk assessment	24 months
Change in CV risk profile	Q-risk assessment	18 months
Change in CV risk profile	Q-risk assessment	12 months
Change in CV risk profile	Q-risk assessment	6 months
Anthropometrics	height (m), weight (m) to calculate body mass index (BMI) as weight divided by height squared,	baseline
Anthropometrics	height (cm), weight (m) to calculate body mass index (BMI) as weight divided by height squared,	24 months
Anthropometrics	height (cm), weight (m) to calculate body mass index (BMI) as weight divided by height squared,	18 months
Anthropometrics	height (cm), weight (m) to calculate body mass index (BMI) as weight divided by height squared,	12 months
Anthropometrics	height (cm), weight (m) to calculate body mass index (BMI) as weight divided by height squared,	6 months
Anthropometrics	heart rate variability (assessed as normal-to-normal (NN) intervals).	baseline
Anthropometrics	blood pressure (mmHg).	baseline
Anthropometrics	blood pressure (mmHg).	6 months
Anthropometrics	blood pressure (mmHg).	12 months
Anthropometrics	blood pressure (mmHg).	18 months
Anthropometrics	blood pressure (mmHg).	24 months
Anthropometrics	heart rate variability (assessed as normal-to-normal (NN) intervals).	24 months
Anthropometrics	heart rate variability (assessed as normal-to-normal (NN) intervals).	18 months
Anthropometrics	heart rate variability (assessed as normal-to-normal (NN) intervals).	12 months
Anthropometrics	heart rate variability (assessed as normal-to-normal (NN) intervals).	6 months
Smoking abstinence	For Groups A, B and D smoking abstinence will be defined by the presence of CO < 10ppm	24 months
Smoking abstinence	For Groups A, B and D smoking abstinence will be defined by the presence of CO < 10ppm	18 months
Smoking abstinence	For Groups A, B and D smoking abstinence will be defined by the presence of CO < 10ppm	12 months
Smoking abstinence	For Groups A, B and D smoking abstinence will be defined by the presence of CO < 10ppm	6 months

Collaborators and Investigators

• Sponsor: Sheffield Hallam University
• Collaborators: Leeds Beckett University

Study record dates

Study Major Dates

• Study Start (Actual): April 16, 2023
• Primary Completion (Estimated): January 30, 2026
• Study Completion (Estimated): June 30, 2026

Study Registration Dates

• First Submitted: February 7, 2023
• First Submitted That Met QC Criteria: February 23, 2023
• First Posted (Actual): March 7, 2023

Study Record Updates

• Last Update Posted (Actual): October 10, 2024
• Last Update Submitted That Met QC Criteria: October 9, 2024
• Last Verified: October 1, 2024

More Information

Terms related to this study

• Keywords: smoking; blood biomarkers; vaping; macrocirculation
• Additional Relevant MeSH Terms: Cardiovascular Diseases
• Other Study ID Numbers: ER49341917

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No