Long-term influence of type 2 diabetes and metabolic syndrome on all-cause and cardiovascular death, and microvascular and macrovascular complications in Chinese adults - A 30-year follow-up of the Da Qing diabetes study

Abstract

Aims: To examine the long-term influence of metabolic syndrome (MetS) on death and vascular complications.

Methods: Altogether, 1419 individuals with different levels of glycemia and MetS were recruited for this study. The participants were followed up for 30 years to assess outcomes.

Results: Compared with the non_MetS, individuals with impaired glucose tolerance (IGT) plus MetS had a higher incidence (per 1000 person-years) of all-cause death (20.98 vs 11.70, hazard ratio [HR] = 1.84), macrovascular events (29.25 vs 15.94, HR = 1.36), and microvascular complications (10.66 vs 3.57, HR = 1.96). The incidence of these outcomes was even higher in participants with type 2 diabetes mellitus (T2DM) plus MetS. The T2DM without MetS shared a comparable risk profile of the outcomes with the T2DM plus MetS group (HRs were 3.45 vs 3.15, 2.21 vs 2.65, and 6.91 vs 7.41, respectively).

Conclusions: The degree of hyperglycemia in MetS is associated with the severity of death and both micro- and macrovascular complications. T2DM was associated with a comparable risk for all outcomes as T2DM plus MetS. The findings highlight the need of early prevention of diabetes in individuals with IGT plus MetS, while the justification to redefine a subgroup of patients with T2DM as having MetS remains to be clarified.

Keywords: Hyperglycaemia; Long-term; Macrovascular events; Metabolic syndrome; Microvascular complication; Type 2 diabetes.