The death statistics for cigarette smoking are already very grim: The U.S. Surgeon General says that more than 480,000 American deaths each year can be attributed to the highly addictive habit.
That’s one of every five deaths in the United States.
The new study also found that the current list of 21 diseases officially linked to smoking may need to be expanded.
These findings show that previous estimates of cigarette-related premature deaths “have substantially underestimated the burden of smoking on society,” writes Dr. Graham Colditz, an epidemiologist at Washington University School of Medicine in St. Louis, in a commentary that accompanies the study. (Colditz was not an author of the study.)
“It is understandable that many people view smoking as a war that we have won, given the large decreases in smoking rates since the 1960s,” Colditz adds. “Although there have been some major victories, the findings of [this new study] show that the war is far from over. Tobacco remains a large and often insidious health burden.”
Some 42 million Americans (including 580,000 adult Minnesotans) smoke cigarettes, according to the Centers for Disease Control and Prevention (and the Minnesota Department of Health). Their death rate is two to three times higher than people who have never smoked, and they die, on average, about a decade earlier.
For the NEJM study, researchers analyzed almost 10 years of data collected from nearly 1 million Americans aged 55 and older who were participating in one of five large studies, such as the Nurses’ Health Study and the National Institutes of Health-AARP Diet and Health Study.
The analysis revealed that, as expected, smokers were dying earlier than people who had never smoked. But the researchers also found that cigarette smoking was associated with only about 83 percent of those extra deaths.
In other words, 17 percent of the premature deaths among smokers in the study could not be attributed to the 21 diseases for which tobacco is already a known cause: 12 types of cancer, six types of cardiovascular disease, pneumonia, diabetes and chronic obstructive pulmonary disease (COPD).
The researchers dug deeper into the data. They found that smokers were twice as likely as people who never smoked to die prematurely from several additional medical conditions: infections, kidney disease, hypertensive heart disease and respiratory illnesses not previously linked to cigarettes.
In addition, smokers were six times more likely to die from intestinal ischemia, a condition that occurs when the arteries to the intestines narrow and become blocked.
The analysis also found that smokers were at a slightly increased risk of dying from breast cancer and prostate cancer.
Two encouraging findings
The NEJM study offers some hopeful news to smokers. It found that the more heavily a person smoked, the greater the risk of premature death. But more important, it also found that the risk of premature death falls over time after individuals kick the habit.
Public health officials and the medical community need to be even more aggressive with their efforts to “end the tobacco epidemic” (as the Department of Health and Human Services has put it), says Colditz.
“The Affordable Care Act provides expanded access to cessation support for many,” he writes, “but holes in Medicaid coverage in many states leave numerous smokers without as much evidence-based support as they need.”
And people whose incomes make them eligible for Medicaid are in particular need of such support. For, as Colditz also points out, 29 percent of American adults below the poverty line smoke compared to only 16 percent of all other adults. In addition, only 6 percent of adults with advanced college degrees smoke, compared to 41 percent of those with a general equivalency degree (GED).
Those general trends hold true here in Minnesota as well. Although the smoking rate among Minnesota’s adults was 14.4 percent in 2014 (the lowest rate in the state’s history), the rate among people with less than a high school education was 28.6 percent.
“Smoking patterns — as with most key health behaviors — are enmeshed with complex societal issues,” Colditz points out, “and successful efforts at prevention and cessation take broad-based multifaceted efforts.