Background: and Purpose Liver enzymes (aspartate aminotransferase [AST], alanine aminotransferase [ALT], and gamma-glutamyl transpeptidase [GGT]) are glutamate-regulatory enzymes, and higher glutamate levels correlated with worse prognosis of patients with neurotrauma. However, less is known about the association between liver enzymes and incidence of stroke. We evaluated the association between serum levels of AST, ALT, and GGT and incidence of stroke in the Atherosclerosis Risk in Communities (ARIC) study cohort from 1990 to 1992 through December 31, 2016. Methods: We included 12,588 ARIC participants without prevalent stroke and with data on liver enzymes ALT, AST, and GGT at baseline. We used multivariable Cox regression models to examine the associations between liver enzymes levels at baseline and stroke risk (overall, ischemic stroke, and intracerebral hemorrhage [ICH]) through December 31, 2016, adjusting for potential confounders. Results: During a median follow-up time of 24.2 years, we observed 1,012 incident strokes (922ischemic strokes and 90 ICH). In age, sex, and race-center adjusted models, the hazard ratios (HRs; 95% confidence intervals [CIs]) for the highest compared to lowest GGT quartile were 1.94 (95% CI, 1.64 to 2.30) for all incident stroke and 2.01 (95% CI, 1.68 to 2.41) for ischemic stroke, with the results supporting a dose-response association (P for linear trend <0.001). Levels of AST were associated with increased risk of ICH, but the association was significant only when comparing the third quartile with the lowest quartile (adjusted HR, 1.82; 95% CI, 1.06 to 3.13). Conclusions Elevated levels of GGT (within normal levels), independent of liver disease, are associated with higher risk of incident stroke overall and ischemic stroke, but not ICH.

BACKGROUND: Our objective was to evaluate the accuracy of cardiovascular disease (CVD) risk score classification by direct LDL cholesterol (dLDL-C), calculated LDL cholesterol (cLDL-C), and non-HDL cholesterol (non-HDL-C) compared to classification by reference measurement procedures (RMPs) performed at the CDC. METHODS: Weexamined 175 individuals, including 138 with CVD or conditions that may affect LDL-C measurement. dLDL-C measurements were performed using Denka, Kyowa, Sekisui, Serotec, Sysmex, UMA, and Wako reagents. cLDL-C was calculated by the Friedewald equation, using each manufacturer's direct HDL-C assay measurements, and total cholesterol and triglyceride measurements by Roche and Siemens (Advia) assays, respectively. RESULTS: For participants with triglycerides <2.26 mmol/L (<200 mg/dL), the overall misclassification rate for the CVD risk score ranged from 5% to 17% for cLDL-C methods and 8% to 26% for dLDL-C methods when compared to the RMP. Only Wako dLDL-C had fewer misclassifications than its corresponding cLDL-C method (8% vs 17%; P<0.05). Non-HDL-C assays misclassified fewer patients than dLDL-C for 4 of 8 methods (P<0.05). For participants with triglycerides > or =2.26 mmol/L (> or =200 mg/dL) and <4.52 mmol/L (<400 mg/dL), dLDL-C methods, in general, performed better than cLDL-C methods, and non-HDL-C methods showed better correspondence to the RMP for CVD risk score than either dLDL-C or cLDL-C methods. CONCLUSIONS: Except for hypertriglyceridemic individuals, 7 of 8 dLDL-C methods failed to show improved CVD risk score classification over the corresponding cLDL-C methods. Non-HDL-C showed overall the best concordance with the RMP for CVD risk score classification of both normal and hypertriglyceridemic individuals.
Cardiovascular Diseases ; Cholesterol ; Cholesterol, LDL ; Humans ; Indicators and Reagents ; Triglycerides