Current smokers endured about a three times greater premature death risk from cardiovascular disease compared to those who have never smoked, according to a study published in the Journal of the American Heart Association.
Researchers analyzed health and demographic data from over 400,000 adults ages 25 to 74 between 1997 and 2014 using the annual U.S. National Health Interview Survey. Occasional and ex-smokers who quit within five years of death were excluded, leaving 390,929 participants.
During the follow-up period, 4,479 people died of cardiovascular disease before age 75. Among this group, about 37 percent were current smokers, compared to about 35 percent of never smokers.
The younger a person started smoking, the higher risk of premature cardiovascular mortality, according to the study. The highest risk was among those who started smoking before age 10, followed by those who reported smoking before age 15.
Quitting at any age "substantially" reduced the premature death risk, with the greatest benefit to those who quit before age 40, the study concluded.