INS and diabetes mellitus: However, another study recruiting postmenopausal women in the Women's Health Initiative study in the USA suggested that diabetes increased the risk of lung cancer (hazard ratio: 1.27, 95% confidence interval: 1.02–1.59), which was more remarkable among patients treated with insulin (hazard ratio: 1.71, 95% confidence interval: 1.15–2.53) (6).