Weight Gain Does Not Attenuate the Mortality Benefit of Smoking Cessation

Although smoking cessation is associated with weight gain, this increase in weight was not associated with increased risk of chronic disease and did not offset the mortality benefit of quitting, according to the results of a recent study published in JAMA Open Network.

Researchers analyzed data from annually updated self-reported smoking status and anthropometric measurements in a representative population of Australian adults aged 18 years and older. Cox proportional hazards regressions were used to determine hazard ratios for the associations between weight changes and mortality as well as chronic disease. The primary study outcome was the association between changes in weight and body mass index and the risk of cardiovascular disease (CVD), type 2 diabetes, cancer, chronic obstructive pulmonary disease (COPD), and mortality.

Among the 16,663 participants, 8082 were men and the mean age was 43.7 years. When smoking status was considered, those who quit smoking had greater increases in weight and body mass index (BMI) than those who continued smoking. However, compared with continuing smokers, the hazard ratios for death were lower among quitters than those who continued smoking.

Specifically, compared with continuing smokers, among individuals who quit smoking and lost weight, the hazard ratio (HR) for the risk of death was 0.50, and among those who quit smoking without weight change, the HR was 0.78. Individuals who quit smoking and gained between 0.1 and 5.0 kg had an HR for the risk of death of 0.24 and those who quit smoking and gained between 5.1 and 10 kg had an HR of 0.36. Compared with continuing smoking, BMI gain following smoking cessation was not associated with significant increases in the risk of CVD, type 2 diabetes, cancer, or COPD.

“These findings suggest that postcessation weight gain poses a trivial risk of harm compared with the benefits of quitting, and smoking interventions should include messages about the safety of postcessation weight gain,” the study authors concluded.

Reference

Sahle BW, Chen W, Rawal LB, Renzaho AMN. Weight gain after smoking cessation and risk of major chronic diseases and mortality. JAMA Netw Open. 2021;4(4):e217044. doi:10.1001/jamanetworkopen.2021.7044