Emmy Keysendal, from the Karolinska Institutet in Stockholm, and colleagues investigated whether the influence of smoking on diabetes risk varied by subtype and explored interaction with genetic susceptibility to diabetes, insulin resistance (IR), and insulin secretion (IS). The analysis included 3,325 people with incident type 2 diabetes (across two cohorts) and 3,897 controls. The researchers found that ever versus never smokers had an increased risk for severe insulin-resistant diabetes (SIRD; relative risk [RR], 2.15). There was an additive interaction between heavy smoking and type 2 diabetes genetic risk score (GRS) and impaired insulin secretion GRS, but not insulin resistance GRS, on the risk for both SIDD and SIRD. “Our findings emphasize the importance of smoking cessation in the prevention of type 2 diabetes,” Keysendal said in a statement.