Cardiovascular Impacts of E-cigarettes Among Older Adults

Tobacco smoking remains a leading cause of chronic disease, premature death, and healthcare costs in the United States. Older adults bear the greatest burden of smoking-related cardiovascular disease (CVD), which is the leading cause of smoking-related mortality. Yet this age group remains significantly underrepresented in tobacco research and is also the only age group not experiencing a decline in smoking prevalence. Hypertension, a key factor connecting smoking to myocardial infarction, stroke, and heart failure, is especially common among older adults who smoke. Although e-cigarettes (ECs) deliver nicotine without combustion and may expose users to fewer harmful toxicants, there is limited evidence on their cardiovascular effects in older adults with pre-existing, smoking-related disease. This R03 project directly addresses a high-priority research area by directly examining the comparative effects of smoking and EC use in humans. The study will employ a rigorous, randomized within-subject crossover design to compare cigarette smoking and exclusive EC use among 30 adults aged 50 and older with hypertension. Participants will complete two 14-day phases: (1) continued smoking and (2) use of an authorized EC product. Aim 1 will evaluate changes in laboratory-based cardiovascular health measures, including resting blood pressure and heart rate, across both conditions. Aim 2 will assess changes in real-world cardiovascular function through remote measurements of blood pressure, heart rate, heart rate variability, and heart rate per step-a novel composite indicator of cardiovascular efficiency. The findings from this study will clarify short-term mechanistic effects of EC switching on cardiovascular health and identify which outcomes and measurement methods are most sensitive to change. This work will provide the first prospective evidence linking laboratory and real-world measures of cardiovascular function in older adults with smoking-related disease, thereby enhancing understanding of the health impacts of EC in populations at the greatest risk for CVD.