Metabolic syndrome in type 1 diabetes and its association with diabetes complications

Aim: To assess the prevalence of metabolic syndrome in type 1 diabetes, and its age-related association with diabetes complications. Methods: Australian National Diabetes Information Audit and Benchmarking (ANDIAB) was a well-established quality audit programme. It provided cross-sectional data on people attending specialist diabetes services across Australia. We determined the prevalence of metabolic syndrome (WHO criteria) in adults with type 1 diabetes and its associations with diabetes complications across age groups. Results: Metabolic syndrome prevalence was 30% in 2120 adults with type 1 diabetes. Prevalence increased with age: 21% in those aged <40 years, 35% in those aged 40–60 years, and 44% in those aged >60 years (P<0.001), which was driven by an increase in hypertension rate. Metabolic syndrome was associated with a higher prevalence of microvascular, macrovascular and foot complications, with the greatest impact at a younger age. The odds ratio for macrovascular complications with metabolic syndrome, compared with without, was 5.9 (95% CI 2.1–16.4) in people aged <40 years, 2.7 (95% CI 1.7–4.2) in those aged 40–60 years, and 1.7 (95% CI 1.1–2.7) in those aged >60 years (all P < 0.05). Metformin use was higher in those with metabolic syndrome (16% vs 4%; P<0.001). Conclusions: In this large Australian cohort, metabolic syndrome was common in type 1 diabetes and identified people at increased risk of the spectrum of diabetes complications, particularly in young to middle-aged adults. Potential clinical implications are that therapies targeting insulin resistance in this high-risk group may reduce diabetes complications and should be explored.