Subclinical Left Ventricular Dysfunction and Glycaemic Control Over Long-term Follow-up in Individuals with Type 2 Diabetes Mellitus: A Prospective Follow-up Study

Background: Subclinical left ventricular dysfunction(LVD) is present in up to half of individuals with type 2 diabetes mellitus(T2DM) and is associated with adverse prognosis. The development of LVD and change in global longitudinal strain(GLS) over long-term follow-up in individuals with T2DM is unknown. Methods: 102 asymptomatic individuals (age 56 ± 8yrs) with T2DM underwent clinical review, blood tests and resting echocardiography at baseline and after a follow-up over 9yrs. Participants were free of ischaemic/valvular heart disease, and had normal ejection fraction(>50%). GLS was used to identify LVD (GLS worse than -18.9%). Results: After 9.4 ± 0.7 years(median), GLS decreased from -19.2 ± 2.3% to -17.4 ± 2.8% (p < 0.001) and there were more individuals with LVD (42% to 68%, p < 0.001). Those with poorer glycaemic control at follow-up (i.e. HbA1c≥7) had significant deterioration in GLS compared to those with optimal control (p = 0.039). Independent predictors of deteriorating GLS were age, weight, HbA1c and use of statins (p < 0.05 for all). Oral antidiabetic medications (including metformin) were protective (p < 0.001). Conclusion: Subclinical LVD is common in asymptomatic individuals with T2DM and progresses over long-term follow-up. Progression of LVD is associated with poor glycaemic control, advancing age, increases in body weight nd statin use, whereas diabetes therapy was protective. Therapeutic interventions in glycaemic control may prevent progression of LVD over long-term follow-up