Thoracic aortic calcification across the clinical dysglycemic continuum in a large Asian population free of cardiovascular symptoms

Functional and prognostic impacts of serum albumin with thoracic arterial calcification among asymptomatic individuals

Although several studies have demonstrated the cardiovascular (CV) implication of hypoalbuminemia and arterial calcification among hemodialysis patients, little is known regarding their cardiac correlates and relevant CV outcomes in asymptomatic individuals. We assessed the potential CV interrelation between serum albumin (SA) and aortic calcification. Among 2,723 asymptomatic individuals underwent cardiovascular health check-up, we assessed serum albumin (SA) level, thoracic aortic calcification (TAC) and coronary artery calcification (CAC) by multi-detector computed tomography, and ultrasound-determined carotid plaque burden. We related these measures to cardiac structure/function and CV outcomes. Lower SA level was associated with higher TAC score and volume rather than carotid plaque or coronary calcification burden in fully adjusted models. By categorizing the study population into 4 groups by SA (>, ≤ 4.6 mg/dL) and presence of TAC, subjects classified into low SA/TAC(+) category were oldest with highest prevalent CV disease. Both lower SA and TAC(+) were independently associated with impaired myocardial systolic/diastolic mechanics and higher CV events during a median of 6.6 years (IQR: 5.1, 6.8 years) follow-up. Participants classified into low SA/TAC(+) category showed highest risk for CV events (adjusted HR: 3.78 [95% CI: 2.11, 6.77], high SA/TAC[-] as reference) in fully adjusted Cox model. Among symptom-free individuals, TAC was closely associated with low SA concentration in relation to unfavorable cardiac mechanics and may serve as a useful prognosticator for adverse CV events.

Volume of the proximal half of the thoracic aorta is the most comprehensive FDG-PET/CT indicator of arterial aging throughout adulthood

INTRODUCTION

¹⁸F-fluorodeoxyglucose positron emission tomography (FDG-PET) and computed tomography (CT) features of the proximal and more elastic half of the thoracic aorta are known to correlate with aorta stiffness in older populations. This prospective study aimed to analyze the changes in these FDG-PET/CT features between young, middle-aged, and older adults, and investigate associations with arterial stiffness and blood pressure (BP).

METHODS

Young (< 40 years), middle-aged (40-to-60 years), and older (> 60 years) adults, who underwent an FDG-PET/CT, were prospectively recruited. FDG-PET/CT features of the proximal half of the thoracic aorta were analyzed relative to the age categories, BP and carotid-femoral pulse wave velocity (PWV), a reference indicator of aorta stiffness.

RESULTS

We included 79 patients (38 women; 22 young, 19 middle-aged, and 38 older adults). An increase in age category was associated with increases in mean standardized uptake values (SUVs) of blood and aorta and most significantly in aorta SUV heterogeneity, represented by SUV standard deviation (SUV-SD), aorta calcification volume, and the aorta volume indexed to body surface area. However, this indexed aorta volume was the sole variable: (i) exhibiting a stepwise increase from young (median: 25 cm³/m² [interquartile range: 20-28 cm³/m²]), to middle-aged (41 [30-48] cm³/m², p < 0.001 vs. Young), and older (62 [44-70] cm³/m², p < 0.001 vs. middle-age) adults, and (ii) selected in the multivariate predictions of systolic, diastolic, and pulse BP. Indexed aorta volume was also a multivariate predictor of PWV but in association with SUV-SD and hypertension.

CONCLUSION

In a population of patients referred to an FDG-PET/CT investigation, the indexed volume of the proximal and more elastic half of the thoracic aorta is the most comprehensive indicator of arterial aging. This imaging parameter exhibits a stepwise increase from young to middle-aged and older adults, is strongly linked to inter-individual changes in both arterial stiffness and BP, and thus, could help assess the early phases of arterial aging. Trial registration ClinicalTrial.gov, NCT03345290. Registered 17 November 2017, https://clinicaltrials.gov/ct2/show/NCT03345290?term=NCT03345290&draw=2&rank=1.

Thoracic Aortic Calcification and Pre-Clinical Hypertension by New 2017 ACC/AHA Hypertension Guidelines

The recently revised 2017 American College of Cardiology/American Heart Association (ACC/AHA) hypertension (HTN) guidelines employ a lower blood pressure threshold to define HTN, aiming for earlier prevention of HTN-related cardiovascular diseases (CVD). Thoracic aortic calcification (TAC), a new surrogate marker of aging and aortic medial layer degeneration, and different stages of HTN, according to the 2017 ACC/AHA HTN guidelines, remain unknown. We classified 3022 consecutive asymptomatic individuals enrolled into four HTN categories using the revised 2017 ACC/AHA guidelines: normal blood pressure (NBP), elevated blood pressure (EBP), and stage 1 (S1) and stage 2 (S2) HTN. The coronary artery calcification score and TAC metrics (total Agaston TAC score, total plaque volume (mm³), and mean density (Hounsfield units, HU)) were measured using multi-detector computed tomography. Compared to NBP, a graded and significant increase in the TAC metrics was observed starting from EBP and S1 and S2 HTN, using the new 2017 ACC/AHA guidelines (NBP as reference; all trends: p < 0.001). These differences remained consistent after being fully adjusted. Older age (>50 years), S1 and S2 HTN, prevalent diabetes, and chronic kidney disease (<60 mL/min/1.73 m²) are all independently contributing factors to higher TAC risk using multivariate stepwise logistic regressions (all p ≤ 0.001). The optimal cutoff values of systolic blood pressure, diastolic blood pressure, and pulse pressure were 121, 74, and 45 mmHg, respectively, for the presence of TAC after excluding subjects with known CVD and ongoing HTN medication treatment. Our data showed that the presence of TAC starts at a stage of elevated blood pressure not categorized as HTN from the updated 2017 ACC/AHA hypertension guidelines.

Correction: Thoracic aortic calcification across the clinical dysglycemic continuum in a large Asian population free of cardiovascular symptoms

[This corrects the article DOI: 10.1371/journal.pone.0207089.].