New-onset T2DM after AMI increased 10-year mortality risk by 41% vs no diabetes (AdjHR 1.408) and 27% vs pre-existing T2DM (AdjHR 1.272), especially under 65 years.
Does new-onset type 2 diabetes mellitus after acute myocardial infarction increase long-term all-cause mortality compared to no diabetes or pre-existing diabetes?
Developing new-onset type 2 diabetes after an acute myocardial infarction identifies a high-risk subgroup with significantly worse long-term survival than even those with pre-existing diabetes.
Background and Objectives: Acute myocardial infarction (AMI) increases the risk of developing type 2 diabetes mellitus (T2DM), yet the long-term prognostic significance of new-onset T2DM after AMI remains unclear. We aimed to evaluate long-term mortality among AMI survivors who developed T2DM during follow-up compared with those who remained non-diabetic and those with pre-existing T2DM. Materials and Methods: We conducted a retrospective cohort study of consecutive AMI patients hospitalized between 2002 and 2017 at a large tertiary medical center. Patients were categorized into three groups: (1) new-onset T2DM after AMI (NOT2DM), 1–15 years post-discharge; (2) no diabetes (No DM), with no evidence of T2DM during the same period; (3) pre-existing T2DM (T2DM), diagnosed prior to or during the index AMI. Age- and sex-matching was performed. Primary outcome: all-cause mortality with up-to 10 years of follow-up. Results: A total of 4207 patients were included (1202 NOT2DM; 2404 No DM; 601 T2DM). Over a median follow-up of 2729 days, 1492 patients (35.5%) died. Mortality was highest in the NOT2DM group (44.9%) compared with No DM (31.2%) and T2DM (33.4%) (p < 0.001). After adjustment, NOT2DM remained strongly associated with increased mortality versus No DM (AdjHR 1.408; 95% CI 1.256–1.578) and T2DM (AdjHR 1.272; 95% CI 1.074–1.508) (p < 0.001 for each). The mortality impact was most pronounced in patients < 65 years. Conclusions: Development of T2DM after AMI identifies a high-risk subgroup with significantly worse long-term survival, especially among the young patients. These findings underscore the need for systematic metabolic surveillance and early preventive strategies in AMI survivors.
Plakht et al. (2026) studied this question. New-onset T2DM after AMI increased 10-year mortality risk by 41% vs no diabetes (AdjHR 1.408) and 27% vs pre-existing T2DM (AdjHR 1.272), especially under 65 years.