Researchers estimate that 4.5 percent of U.S. adults, a projected 10.8 million people, were current e-cigarette users in 2016. | Courtesy of Wikimedia Commons

This story has been updated.

Kentuckians have embraced electronic cigarettes despite the jury still being out on the health consequences of the trendy devices, according to recently published research.

The study by researchers from the American Heart Association Tobacco Regulation and Addiction Center (A-TRAC) shows that Kentucky is fifth among U.S. states and various territories for daily e-cigarette use. It’s also in the top 10 for current use, which includes both daily and occasional use, according to the study, which is based on data from a 2016 survey.

Looking at the nation as a whole, researchers estimated that there were about 10.8 million adult users of e-cigarettes nationwide in 2016, with 18- to 24-year-olds (or 2.8 million people) having the highest prevalence of current use.

“Over half of the (current) users are under the age of 35,” said the senior author, Dr. Michael Blaha, who’s director of clinical research for the Johns Hopkins Ciccarone Center for the Prevention of Heart Disease.

Blaha also noted that “15 percent of total users have never used cigarettes before,” so presumably e-cigarettes are their first tobacco product. “That’s interesting and potentially concerning,” he said.

E-cigarettes were introduced in the United States more than a decade ago, and some people in the medical community continue to be concerned about their safety and utility, according to the paper, which appeared recently in the Annals of Internal Medicine.

However, the study is intended to be “basically a snapshot of e-cigarette users in the country in 2016,” Blaha said. “It’s not trying to make any case for or against e-cigarette usage, just kind of documenting their usage.”

For the most part, the study found e-cigarette use to be highest in southern and western states.

In Kentucky, the prevalence of current use among adults was 5.9 percent, so it can be estimated that there were more than 206,000 such users in the commonwealth in 2016, according to Aruni Bhatnagar, who is part of the A-TRAC at UofL, one of a dozen such centers. He’s also an author on the paper.

With prevalence of daily use at 2.3 percent, more than 80,000 Kentucky adults were vaping every day, Bhatnagar said.

The high use of e-cigarettes in Kentucky is likely a reflection of the state being a place where tobacco use is high, Bhatnagar said. “If you have a high number of smokers to begin with, you’re going to have a high number of people who are using e-cigs,” he said.

The National Academies of Sciences, Engineering, and Medicine issued a report earlier this year that concluded that while e-cigarettes are not without health risks, they are likely to be far less harmful than conventional cigarettes.

“E-cigarettes cannot be simply categorized as either beneficial or harmful,” David Eaton, chair of the committee that wrote the report, said in a news release at the time. “In some circumstances, such as their use by non-smoking adolescents and young adults, their adverse effects clearly warrant concern. In other cases, such as when adult smokers use them to quit smoking, they offer an opportunity to reduce smoking-related illness.”

Dr. Sarah Moyer | Photo courtesy of Metro Government

But Dr. Sarah Moyer, director of the Louisville Metro Department of Public Health and Wellness, expressed concern about the findings.

“The growing use of e-cigarettes threatens to reverse the trend of making nicotine addiction less socially acceptable and of falling smoking rates,” Moyer said in a written statement.  “Their use in public places also poses health dangers to non-users from secondhand exposure. That’s why e-cigarettes are now included under Louisville’s comprehensive smoke-free law, which prohibits the use of cigarettes, e-cigarettes and hookah in indoor public places. Healthy Louisville 2020 and the 2017 Health Equity Report recommend increasing the tax on tobacco products. This includes e-cigarettes.”

Bhatnagar, who directs UofL’s Envirome Institute, made similar comments, noting, “In young people, smoking is no longer cool or socially acceptable, and now with the advent of e-cigarettes, it can erode all the gains that we’ve been making in trying to contain nicotine addiction.”

Bhatnagar said nicotine isn’t good for young adults, whose brains are still developing. He thinks it could do harm in terms of their mental development.

“Secondly, it could also affect their cardiovascular health,” he said. “Third and perhaps more importantly is that they can be addicted and once you get addicted to nicotine, it’s relatively easy to switch to regular cigarettes.”

Dual usage, which refers to using both e-cigarettes and regular cigarettes, was the most common pattern of usage in the study, which used data from the U.S. Centers for Disease Control and Prevention’s Behavioral Risk Factor Surveillance System, Blaha said.

Aruni Bhatnagar | Courtesy of UofL

People could be using both because they’re on their way to quitting or because e-cigarettes are more socially acceptable in some places, or e-cigarettes might be “reinforcing the nicotine addiction rather than helping one get off the nicotine addiction. Our snapshot doesn’t allow us to conclude either way, but clearly most users actually are dual users,” Blaha said.

In looking at specific populations, the study found e-cigarette use was high among lesbian or gay, bisexual and transgender people. Others with high prevalence included people with cardiovascular disease, asthma, cancer, chronic obstructive pulmonary disease and depression.

Future research should focus on why use is so high in various subgroups, Bhagnagar said. Also, “we would want FDA to target anti-tobacco, anti-smoking campaigns to specific demographic groups like LGBTQ.”

This story has been corrected to note that 2.8 million people is the number of 18-24 year olds who were current users of e-cigarettes.