Coronary artery calcium in patients with schizophrenia

The association of carotid plaque burden and composition and the coronary artery calcium score in intermediate cardiovascular risk patients

Both the carotid ultrasound and coronary artery calcium (CAC) score quantify subclinical atherosclerosis and are associated with cardiovascular disease and events. This study investigated the association between CAC score and carotid plaque quantity and composition. Adult participants (n = 43) without history of cardiovascular disease were recruited to undergo a carotid ultrasound. Maximum plaque height (MPH), total plaque area (TPA), carotid intima-media thickness (CIMT), and plaque score were measured. Grayscale pixel distribution analysis of ultrasound images determined plaque tissue composition. Participants then underwent CT to determine CAC score, which were also categorized as absent (0), mild (1-99), moderate (100-399), and severe (400+). Spearman correlation coefficients between carotid variables and CAC scores were computed. The mean age of participants was 63 ± 11 years. CIMT, TPA, MPH, and plaque score were significantly associated with CAC score (ρ = 0.60, p < 0.0001; ρ = 0.54, p = 0.0002; ρ = 0.38, p = 0.01; and ρ = 0.49, p = 0.001). Echogenic composition features %Calcium and %Fibrous tissue were not correlated to a clinically relevant extent. There was a significant difference in the TPA, MPH, and plaque scores of those with a severe CAC score category compared to lesser categories. While carotid plaque burden was associated with CAC score, plaque composition was not. Though CAC score reliably measures calcification, carotid ultrasound gives information on both plaque burden and composition. Carotid ultrasound with assessment of plaque features used in conjunction with traditional risk factors may be an alternative or additive to CAC scoring and could improve the prediction of cardiovascular events in the intermediate risk population.

The relationship between serum vitamin K concentration and coronary artery calcification in middle-aged and elderly people

BACKGROUND

Vitamin K is involved in the formation of coronary artery calcification which is an independent predictor of coronary heart disease. This study aims to explore the association between coronary artery calcification score and serum concentrations of vitamin K1, menaquinone-4 (MK-4) and menaquinone-7 (MK-7) in middle-aged and elderly Chinese population.

METHODS

A total of 116 patients who underwent CT coronary angiography were consecutively enrolled. Serum concentrations of vitamin K1, MK-4 and MK-7 were determined by high performance liquid chromatography tandem mass spectrometry. The relationships between coronary artery calcification score and serum vitamin K concentrations were analyzed.

RESULTS

Significantly lower serum vitamin K1 concentration was found in the patients with CACS > 400, comparing with the other CACS categories, respectively. Log (CACS + 1) was significantly higher in MK-4 < 0.05 ng/ml group compared with MK-4 ≥ 0.05 ng/ml group [2.03(0.21, 2.58) vs 1.31(0.00, 2.19), P < 0.05]. In subjects with established coronary calcification (defined as CACS > 10), vitamin K1 was found to be an independent factor contributing to higher CACS (r = -0.288, P = 0.013).

CONCLUSIONS

In this retrospective analysis, serum vitamin K1 and MK-4 concentrations were significantly lower in middle-aged and elderly cohorts with increasing calcification scores. The significant effect of vitamin K1 on CACS was only found in individuals who already had calcification. Whether the detection of circulating vitamin K in patients with preexisting coronary calcification could guide vitamin K supplementation needs further exploration.