Abstract
BACKGROUND: The value of the triglyceride-glucose (TyG) index for predicting the prognosis in patients with hypertrophic cardiomyopathy (HCM) and heart failure with preserved ejection fraction (HFpEF) remains unexplored. METHODS: Patients from 15 centers were included. The primary outcome was all-cause mortality. The secondary outcomes were cardiovascular mortality and sudden cardiac death (SCD). Restricted cubic spline analyses, multivariate Cox regression analyses, competing risk models, subgroup and mediation analyses were used to assess the relationship between the TyG index and outcomes. RESULTS: A total of 1095 patients with HCM and HFpEF were included. During a median follow-up period of 69 months, 224 all-cause deaths, 142 cardiovascular deaths, and 56 SCDs occurred. Multivariable Cox regression showed that the highest TyG index quartile was associated with a lower incidence of all-cause (hazard ratio (HR) 0.74, 95% CI 0.56-0.99, P = .046) and cardiovascular mortality (HR 0.65, 95% CI 0.44-0.94, P = .024) compared to the lowest quartile. However, no significant association was found between the TyG index and SCD (HR 0.74, 95% CI 0.41-1.31, P = 0.300). The competing risk model confirmed a significant association between the TyG index and reduced cardiovascular mortality (HR, 0.56; 95%CI, 0.40-0.78, P = .001) but no significant association with SCD (HR, 0.69; 95% CI, 0.37-1.27, P = .230). Mediation analyses indicated N-terminal pro-B-type natriuretic peptide mediated the association between TyG index and cardiovascular survival, while serum creatinine had a suppression effect. CONCLUSION: A higher TyG index was associated with lower risks of all-cause and cardiovascular mortality but with no significant influence on SCD risk in patients with HCM and HFpEF.