Background: A relatively young age at diagnosis of type 2 diabetes (T2DM) is observed in non-Anglo-Celt populations and is associated with a poor prognosis.
Aim: To compare the characteristics and risk of death of Anglo-Celts with T2DM by age at diagnosis.
Patients and Methods: The longitudinal Fremantle Diabetes Study (FDS) Phase II includes 827 Anglo-Celt subjects with T2DM recruited between 2008 and 2011 and followed to death/census at end-March 2014.
Results: At baseline, the Anglo-Celts had a mean±SD age of 67.5±10.6 years, 51% were male, and their median [inter-quartile range] diabetes duration was 8.8 [2.8-15.3] years. Those diagnosed at age <55 years (n=302) were younger at FDS entry (60.2±9.7 vs 72.3±8.0 years, P<0.001), more likely to be male (56.0% vs 48.4%, P=0.033), and had longer diabetes duration (13.0 [6.1-18.6] vs 5.2 [1.4-12.2] years, P<0.001) than those diagnosed later. They also were more obese and more likely to be depressed, had worse glycaemic control despite more intensive management, lower HDL-cholesterol and higher serum triglycerides (P≤0.022). However, a smaller proportion had vascular complications. During a mean follow up of 4.4±1.1 years, 7.5% of the younger onset group and 13.4% of the older onset group died (P=0.009). Cox proportional hazards modelling with age as the time-line showed that all-cause mortality was predicted by male sex, current smoking and eGFR category, whilst being married/in a de facto relationship was protective. After adjusting for this most parsimonious model and adding age at diagnosis as a dichotomous variable, diagnosis at age <55 years independently predicted higher mortality (hazard ratio (95% CI): 2.71 (1.59-4.62), P<0.001).
Conclusions: These community-based data show that Anglo-Celt Australians with T2DM diagnosed at a young age have a subsequently increased risk of death. These patients may need more intensive glycaemic and weight management, and treatment for depression.