Early and ongoing stable glycaemic control is associated with a reduction in major adverse cardiovascular events in people with type 2 diabetes: a primary care cohort study

Journal article

Aim: To determine whether achieving early glycaemic control, and any subsequent glycaemic variability, was associated with any change in the risk of major adverse cardiovascular events (MACE).

Materials and Methods: A retrospective cohort analysis from the Oxford-Royal College of General Practitioners Research and Surveillance Centre database—a large, English primary care network—was conducted. We followed newly diagnosed patients with type 2 diabetes, on or after 1 January 2005, aged 25 years or older at diagnosis, with HbA1c measurements at both diagnosis and after 1 year, plus five or more measurements of HbA1c thereafter. Three glycaemic bands were created: groups A (HbA1c < 58 mmol/mol [<7.5%]), B (HbA1c ≥ 58 to 75 mmol/mol [7.5%-9.0%]) and C (HbA1c ≥ 75 mmol/mol [≥9.0%]). Movement between bands was determined from diagnosis to 1 year. Additionally, for data after the first 12 months, a glycaemic variability score was calculated from the number of successive HbA1c readings differing by 0.5% or higher (≥5.5 mmol/mol). Risk of MACE from 1 year postdiagnosis was assessed using time-varying Cox proportional hazards models, which included the first-year transition and the glycaemic variability score.

Results: From 26 180 patients, there were 2300 MACE. Compared with group A->A transition over 1 year, those with C->A transition had a reduced risk of MACE (HR 0.75; 95% CI 0.60-0.94; P = .014), whereas group C->C had HR 1.21 (0.81-1.81; P = .34). Compared with the lowest glycaemic variability score, the greatest variability increased the risk of MACE (HR 1.51; 1.11-2.06; P = .0096).

Conclusion: Early control of HbA1c improved cardiovascular outcomes in type 2 diabetes, although subsequent glycaemic variability had a negative effect on an individual's risk.

Authors: Whyte, MB; Joy, M; Hinton, W; McGovern, A; Hoang, U

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Wiley
• Journal: Diabetes, Obesity and Metabolism
• Volume: 24
• Issue: 7
• Pages: 1310-1318
• Publication date: 2022-04-18
• Acceptance date: 2022-03-30
• DOI: 10.1111/dom.14705
• EISSN: 1463-1326
• ISSN: 1462-8902
• Pmid: 35373891
• Language: English
• Keywords: FFR; type 2 diabetes mellitus; glycated hemoglobin; retrospective studies; glycemic control; blood glucose; cohort studies; cardiovascular diseases; primary health care