E-cigarettes and urologic health: a collaborative review of toxicology, epidemiology, and potential risks

Context: Use of electronic cigarettes (ECs) is on the rise in most high-income countries. Smoking conventional cigarettes is a known risk factor for urologic malignancy incidence, progression, and mortality, as well as for other urologic health indicators. The potential impact of EC use on urologic health is therefore of clinical interest to the urology community. Objective: To review the available data on current EC use, including potential benefits in urologic patients, potential issues linked to toxicology of EC constituents, and how this might translate into urologic health risks. Evidence acquisition: A Medline search was carried out in August 2016 for studies reporting urologic health outcomes and EC use. Snowballing techniques were also used to identify relevant studies from recent systematic reviews. A narrative synthesis of data around EC health outcomes, toxicology, and potential use in smoking cessation and health policy was carried out. Evidence synthesis: We found no studies to date that have been specifically designed to prospectively assess urologic health risks, even in an observational setting. Generating such data would be an important contribution to the debate on the role of ECs in public health and clinical practice. There is evidence from a recent Cochrane review of RCTs that ECs can support smoking cessation. There are emerging data indicating that potentially harmful components of ECs such as tobacco-specific nitrosamines, polyaromatic hydrocarbons, and heavy metals could be linked to possible urologic health risks. Conclusions: ECs might be a useful tool to encourage cessation of conventional cigarette smoking. However, data collection around the specific impact of ECs on urologic health is needed to clarify the possible patient benefits, outcomes, and adverse events. Patient summary: While electronic cigarettes might help some people to stop smoking, their overall impact on urologic health is not clear. While electronic cigarettes might help some people to stop smoking, it is not clear if they may be bad for urologic health.