While smoking is tough enough on health, adding in diabetes boosts the risk of an early death even more, new research confirms.
Heavy smokers who also have diabetes are at twice the risk of an early death compared to smokers without the blood sugar disease, the study found.
"Smoking is bad for all, but even more in those with diabetes," said Dr. Joel Zonszein, director of the Clinical Diabetes Center at Montefiore Medical Center in New York City. He reviewed the new findings.
The study was conducted by researchers at the University of Colorado, Anschutz, and involved data on more than 53,000 Americans who were either current or former heavy smokers.
The overall risk of an early death was roughly double if the smoker had diabetes, the researchers reported. Overall, almost 13 percent of smokers with diabetes died during the seven-year study period, compared with just under 7 percent of those who weren't diabetic.
Women with diabetes seemed even more vulnerable than men when it came to lung cancer, specifically.
The study found that female smokers with diabetes had an 80 percent higher risk of dying from lung cancer, compared with female smokers who didn't have the illness.
That trend was not seen among men, however. For males, having diabetes was tied to higher odds for early death overall, but it did not seem to be linked to higher risk of dying from lung cancer, specifically, the findings showed.
According to study lead researcher Dr. Kavita Garg, the findings indicate that "taking control of diabetes is important among smokers, whether they undergo screening for lung cancer or not, because diabetes is an independent risk factor for dying."
Garg is a professor of radiology at the university. In the study, her team looked at data from people who took part in the National Lung Screening Trial. That U.S. trial compared CT chest scans against chest X-rays, to see how each fared as early screening for lung cancer in current and former heavy smokers.
More than 5,000 of the smokers in the trial (nearly 10 percent) also had diabetes. Participants with diabetes tended to be older, and to smoke and weigh more than those without diabetes, the researchers noted.
Garg's team analyzed the risk of dying from lung cancer, other cancers and from any cause. Over the seven years of the trial, nearly 4,000 participants died, including more than 1,000 from lung cancer and more than 800 from other cancers.
Zonszein said the new findings should come as little surprise.
"We all know that smoking is not good for patients with diabetes -- it worsens peripheral artery disease [poor leg circulation] and heart disease, and predisposes people to an early lung cancer death or disability by chronic obstructive lung disease [COPD]," he said.
More than 29 million people in the United States have diabetes, according to the U.S. Centers for Disease Control and Prevention.
Dr. Gerald Bernstein, an endocrinologist and coordinator of the Friedman Diabetes Program at Lenox Hill Hospital in New York City, added that "the bigger picture makes these findings even more ominous."
That's because even among people with pre-diabetes -- a precursor to diabetes -- "smoking is as big a risk for dying as high blood pressure and high cholesterol," Bernstein said.
Bernstein concedes that quitting smoking is hard, and takes more effort than just taking a pill to control blood pressure or cholesterol.
But, another expert said, battling a smoking habit and diabetes at once can be challenging.
"When patients are diagnosed with diabetes, quitting smoking does not always seem like a top priority," said Patricia Folan. She directs the Center for Tobacco Control at Northwell Health in Great Neck, N.Y.
Patients are often overwhelmed by the many lifestyle changes required to control their diabetes, she said.
"Often, what is not appreciated is the fact that the complications of diabetes -- an increased risk of heart attack and stroke, damage to blood vessels, kidney disease, infections, ulcers, amputations and blindness -- are more likely to occur if you are smoking," Folan explained.
However, "quitting smoking will improve the overall health of patients with diabetes and make it easier for them to exercise and control their diabetes while avoiding the complications of the disease," she added.
The results of the study were scheduled to be presented Tuesday at a meeting of the Radiological Society of North America in Chicago. Data presented at medical meetings should be considered preliminary until published in a peer-reviewed journal.
For more on smoking and type 2 diabetes, visit the U.S. Centers for Disease Control and Prevention.