Association between waist-to-height-haemoglobin A1c index and subclinical myocardial injury in individuals with and without hypertension

Recently, a novel metabolic indicator, the Waist-to-Height-Haemoglobin A1c (WHH) index, has been shown to be associated with diabetes risk. This study investigated the association of WHH with the Cardiac Infarction/Injury Score (CIIS) and the risk of subclinical myocardial injury (SC-MI), stratified by hypertension status. We conducted a cross-sectional analysis of 5,597 adults aged ≥40 years from the Third National Health and Nutrition Examination Survey who were free of CVD. The WHH index was calculated as waist circumference/height × HbA1c. SC-MI was defined as a CIIS ≥10 on a 12-lead electrocardiogram. Using weighted generalised linear and logistic regression models, we examined the associations of WHH with CIIS and SC-MI. Nonlinear relationships were assessed using restricted cubic spline (RCS) models. The WHH index was not associated with SC-MI among adults without hypertension (odds ratio [OR], 0.95; 95% confidence interval [CI], 0.73–1.24 per SD increase), but was positively associated among adults with hypertension (OR, 1.37; 95% CI, 1.08–1.72; Pinteraction = 0.007). For the CIIS, each 1-SD higher WHH index was positively associated only among those with hypertension (β = 0.81; 95% CI, 0.12 to 1.63; Pinteraction = 0.020). RCS analysis confirmed a linear relationship between WHH and SC-MI risk among individuals with hypertension. These findings demonstrate a significant association between the WHH index and subclinical myocardial injury, particularly among adults with hypertension.