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Background: The strength of association and optimal levels for risk factors related to excess risk of death and cardiovascular outcomes in type 1 diabetes mellitus have been sparsely studied., Methods: In a national observational cohort study from the Swedish National Diabetes Register from 1998 to 2014, we assessed relative prognostic importance of 17 risk factors for death and cardiovascular outcomes in individuals with type 1 diabetes mellitus. We used Cox regression and machine learning analyses. In addition, we examined optimal cut point levels for glycohemoglobin, systolic blood pressure, and low-density lipoprotein cholesterol. Patients with type 1 diabetes mellitus were followed up until death or study end on December 31, 2013. The primary outcomes were death resulting from all causes, fatal/nonfatal acute myocardial infarction, fatal/nonfatal stroke, and hospitalization for heart failure., Results: Of 32 611 patients with type 1 diabetes mellitus, 1809 (5.5%) died during follow-up over 10.4 years. The strongest predictors for death and cardiovascular outcomes were glycohemoglobin, albuminuria, duration of diabetes mellitus, systolic blood pressure, and low-density lipoprotein cholesterol. Glycohemoglobin displayed ≈2% higher risk for each 1-mmol/mol increase (equating to ≈22% per 1% glycohemoglobin difference), whereas low-density lipoprotein cholesterol was associated with 35% to 50% greater risk for each 1-mmol/L increase. Microalbuminuria or macroalbuminuria was associated with 2 to 4 times greater risk for cardiovascular complications and death. Glycohemoglobin <53 mmol/mol (7.0%), systolic blood pressure <140 mm Hg, and low-density lipoprotein cholesterol <2.5 mmol/L were associated with significantly lower risk for outcomes observed., Conclusions: Glycohemoglobin, albuminuria, duration of diabetes mellitus, systolic blood pressure, and low-density lipoprotein cholesterol appear to be the most important predictors for mortality and cardiovascular outcomes in patients with type 1 diabetes mellitus. Lower levels for glycohemoglobin, systolic blood pressure, and low-density lipoprotein cholesterol than contemporary guideline target levels appear to be associated with significantly lower risk for outcomes.

Background: Some, but not all, studies have reported a relationship between plasma insulin and coronary heart disease (CHD). Conventional nonspecific insulin assays are also measuring various fractions of proinsulin-like molecules due to cross-reactivity. The long-term relationship between proinsulin-like molecules and CHD is largely unknown. For this reason, the longitudinal relationships between intact proinsulin, split proinsulin, specific insulin, immunoreactive insulin, and CHD, were studied in a population-based cohort of 50-year-old men (n=874), with a follow-up of 27 years., Methods and Results: Fasting proinsulin-like molecule and specific-insulin concentrations were measured in plasma (stored frozen since baseline 1970 to 1973) by specific 2-site immunometric assays. Immunoreactive insulin concentrations were determined at baseline. The associations between proinsulin-like molecules, specific insulin, immunoreactive insulin, and CHD mortality (International Classification of Diseases [9th revision] codes 410 to 414) were analyzed using Cox's proportional hazards regression and presented as hazard ratios (HRs) with their 95% confidence intervals (CIs) for a 1-SD increase in a predictor variable. In the univariate analysis, intact proinsulin (HR, 1.69; 95% CI, 1.41 to 2.01) was the strongest predictor of death from CHD. In the multivariate analysis, smoking (HR, 1.57; 95% CI, 1.03 to 2.38), intact proinsulin (HR, 1.47; 95% CI, 1.18 to 1.82), systolic blood pressure (HR, 1.38; 95% CI, 1.14 to 1.66), and LDL/HDL cholesterol ratio (HR, 1.31; 95% CI, 1.12 to 1.53) were independent predictors of CHD mortality (adjusted for body mass index, triglycerides, and fasting glucose), whereas specific insulin and immunoreactive insulin were not (HR, 1.12; 95% CI, 0.90 to 1.40). The increased risk was restricted to the upper third of the proinsulin distribution., Conclusion: Increased proinsulin concentrations predict death and morbidity caused by CHD over a period of 27 years, independent of other major cardiovascular risk factors.