Triglyceride to HDL-cholesterol ratio is a predictor of future coronary events: a possible role of high-risk coronary plaques detected by coronary CT angiography
Authors: Miki T , Miyoshi T , Suruga K , Ichikawa K , Otsuka H , Toda H , Yoshida M , Nakamura K , Morita H , Ito H 
Published: November 2020

Abstract

Background
For the prevention of future cardiovascular events, control of residual risks such as triglyceride rich lipoproteins and HDL-cholesterol is an emerging problem beyond LDL-cholesterol. Triglyceride to HDL-cholesterol ratio (TG/HDL ratio) has been reported to be useful for risk classification of cardiovascular diseases. Meanwhile, several studies showed that high-risk plaque characteristics evaluated with coronary CT angiography (cCTA) was associated with the incidence of acute coronary syndrome. However, the relationship of TG/HDL ratio with coronary plaque characteristics and its impact of this association on future coronary events have not been fully elucidated.

Purpose
The aim of this study was to evaluate the association between TG/HDL ratio and high-risk plaque detected by cCTA and its impact on future coronary events.

Methods
A total of 944 patients suspected stable coronary artery disease who underwent cCTA at our institution were analyzed (mean 64-year-old, 55% male). Patients were divided into two groups by the median value of TG/HDL ratio (higher TG/HDL: TG/HDL ratio ≥2.0, lower TG/HDL: TG/HDL ratio &lt;2.0). Coronary high-risk plaques were defined as a plaque with all three components; low attenuation plaque (&lt;50H.U.), positive remodeling (remodeling index &gt;1.1) and spotty calcification. Cardiovascular event was defined as cardiovascular death, acute coronary syndrome, and late coronary revascularization after 30 days of CT acquisition.

Results
The higher TG/HDL ratio was significantly associated with male gender (63% vs. 48%, P&lt;0.001), body mass index (24.8±3.8 vs. 22.9±4.0, p&lt;0.001), the prevalence of hypertension (65% vs. 54%, P&lt;0.001), dyslipidemia (60% vs. 42%, P&lt;0.001), diabetes mellitus (38% vs. 27%, P=0.001) and current smoking (26% vs. 10%, p&lt;0.001). Regarding cCTA findings, the prevalence of significant stenosis, calcified plaque, non-calcified plaque, coronary plaques with low attenuation plaque, positive remodeling and spotty calcification in the higher TG/HDL group were greater than those in the lower group (Figure 1A). Of note, the difference in high-risk plaque between two groups was significant. (18% vs. 11%, p=0.004). Multivariate logistic analysis revealed that the TG/HDL ratio was an independent risk factor for high-risk plaque even after adjustment (OR, 1.35; 95% CI, 1.01–1.81; p=0.049). Regarding coronary events (median follow-up duration; 48 months), Kaplan-Meier curve showed poor event-free rate in the higher TG/HDL group (Figure 1B). At Cox proportional hazard analysis, higher TG/HDL ratio (HR, 1.94; 95% CI, 1.01–3.70; p=0.046) and CT-verified high-risk plaque (HR, 2.36; 95% CI, 1.27–4.38; p=0.006) were independent predictive factors for coronary events even after adjustment.

Conclusion
TG/HDL ratio is involved in the vulnerability of CT-verified coronary plaque characteristics. This association may play an important role in the prognostic impact of TG/HDL ratio on future cardiovascular events.

Funding Acknowledgement
Type of funding source: None