Associations of clinical frailty and the triglyceride-glucose index with major adverse cardiovascular events in older adults with acute coronary syndrome in southern Vietnam: a prospective multicentre cohort study

Objectives To examine the associations of clinical frailty and the triglyceride-glucose (TyG) index, individually and jointly, with 12-month major adverse cardiovascular events (MACE) in older adults with acute coronary syndrome (ACS). Design Prospective cohort study. Setting Two tertiary hospitals in southern Vietnam. Participants Adults aged ≥60 years admitted with ACS who underwent coronary angiography and had obstructive coronary artery disease, defined as ≥50% stenosis in at least one coronary artery. Of 447 patients enrolled, 433 were discharged alive and 401 were included in the 12-month post-discharge analysis. Primary and secondary outcome measures The primary outcome was 12-month post-discharge MACE, defined as a composite of all-cause death, recurrent myocardial infarction, stroke, hospitalisation for heart failure and hospitalisation for unstable angina. Frailty was defined as a Clinical Frailty Scale score≥5, and high TyG was defined using the cohort median. Results Among 401 participants, 135 experienced MACE. Event proportions were 21.4%, 36.8%, 24.6% and 62.5% in the non-frailty/low-TyG, non-frailty/high-TyG, frailty/low-TyG and frailty/high-TyG groups, respectively. High TyG was associated with 12-month MACE after multivariable adjustment (adjusted HR 1.91, 95% CI 1.30 to 2.80, p<0.001), whereas the association with frailty alone was attenuated (adjusted HR 1.46, 95% CI 0.95 to 2.25, p=0.080). Compared with the non-frailty/low-TyG group, the frailty/high-TyG group had an adjusted HR of 2.78 (95% CI 1.58 to 4.88, p<0.001). The multiplicative interaction between frailty and high TyG was not statistically significant (p=0.331). Conclusions In older adults with ACS, high TyG remained associated with 12-month MACE after multivariable adjustment, whereas the association with frailty alone was attenuated. Patients with both frailty and high TyG had the highest observed event proportion and the largest adjusted HR relative to the non-frailty/low-TyG group. These findings suggest that combined assessment of frailty and TyG may provide complementary information for post-ACS risk assessment.