INS and diabetes mellitus: After adjustment for potential confounders based on the multivariate Cox model, the presence of diabetes remained associated with lower survival, regardless of the need for insulin therapy (Fig. 4): stepwise selection adjusted HR for diabetes on insulin vs no diabetes was 2.13 (95% CI 1.68–2.68, p < 0.0001), for diabetes not on insulin vs no diabetes was HR 1.32 (95% CI 1.11–1.57, p = 0.0015).