Diabetes, Smoking May Increase Mortality Risk

Researchers discovered a statistically significant link between diabetes and all-cause mortality.

Cigarettes are known to be carcinogenic, and cause lung cancer in a majority of individuals that smoke. Findings from a recent study suggest that patients with diabetes who smoke have an increased risk of death from causes other than lung cancer.

The CDC reported that more than 29 million adults in the United States have diabetes, which jumped from 26 million in 2010. Approximately 1 in 4 individuals with diabetes are unaware of their condition, which can result in uncontrolled blood glucose levels and can put the patient at greater risk for other comorbidities from lack of treatment.

Researchers in the National Lung Screening Trial examined patients with or without diabetes who smoked to determine the link between diabetes and deaths from lung cancer, other cancers, and other causes. The findings will be presented next week at the annual meeting of the Radiological Society of North America.

Of the 53,454 patients included in the trial, 5174 individuals reported they had diabetes during the initial screening. Researchers used low-dose helical CT and chest X-ray to screen the patients for lung cancer.

“In our study, we found a statistically significant link between diabetes and all-cause deaths, non-lung cancer deaths and lung cancer deaths in women,” said researcher Kavita Garg, MD.

The researchers adjusted for age, gender, body mass index, and years of smoking to analyze the relative risk for overall mortality, and lung cancer and non-lung cancer mortality, according to the study. Patients with diabetes were typically older, smoked longer, and had a higher body mass index compared with patients who did not have diabetes.

During the trial period, 3936 patients died from various causes, which includes 1021 patients who died from lung cancer, and an additional 826 patients who died from other cancers.

Approximately 12.6% (650 patients) of the population with diabetes died during the trial, compared with 6.8% (3286 patients) without diabetes, according to the study.

“We found that diabetes doubles the risk for all-cause mortality and non-lung cancer mortality among heavy smokers,” Dr Garg said. “We also found that women with diabetes have an increased risk of lung-cancer mortality, but did not find the same effect in men.”

Researchers plan to continue analyzing these findings to get a better understanding of the reasons behind this association. However, they emphasize that patients must achieve disease control and receive lung cancer screenings if they smoke.

"Patients have to take care of their diabetes to maximize the benefit of CT screening for lung cancer," Dr Garg concluded. "It truly makes a magnitude of difference in mortality risk.”