RESUMO
BACKGROUND AND AIMS: l-Carnitine was suggested to prevent the progression of atherosclerosis, myocardial and neurologic injury, and exhibited cardioprotective effects. However, epidemiological data on circulating l-carnitine and risks of cardiovascular events in the setting of stroke is rare. We aimed to explore the relationships between plasma l-carnitine and cardiovascular events and stroke recurrence after ischemic stroke in a nested case-control study. METHODS AND RESULTS: A total of 323 cardiovascular events (including 264 recurrent strokes) and 323 matched controls (free of recurrent cardiovascular events) were included. Study outcomes included cardiovascular events and recurrent stroke after ischemic stroke. Plasma l-carnitine concentrations were measured by ultra-high-performance LC-MS/MS. Conditional logistic regression models were used to estimate odds ratios (ORs) of stroke outcomes. Plasma l-carnitine was inversely associated with cardiovascular events (OR = 0.69, 95% CI: 0.57-0.84 per SD) and recurrent stroke (OR = 0.72, 95% CI: 0.58-0.88 per SD) after adjusting for established risk confounders. Compared with the lowest tertile of l-carnitine, adjusted ORs of cardiovascular events and recurrent stroke for participants in the highest tertiles were 0.35 (95% CI: 0.21-0.57) and 0.36 (95% CI: 0.21-0.62), respectively. In addition, l-carnitine provided incremental predictive ability beyond established risk factors, shown by increase in C statistics, net reclassification improvement and integrated discrimination improvement. CONCLUSIONS: Higher l-carnitine levels were associated with lower risks of cardiovascular events and recurrent stroke after ischemic stroke. Our findings provided evidence supporting plasma l-carnitine as a potential prognostic marker in risk discrimination and stratification in patients with ischemic stroke. TRIAL REGISTRATION: Clinicaltrials.gov as NCT01840072. URL: https://www. CLINICALTRIALS: gov.
Assuntos
Carnitina , AVC Isquêmico , Acidente Vascular Cerebral , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biomarcadores , Carnitina/efeitos adversos , Estudos de Casos e Controles , Cromatografia Líquida , Eletrólitos , AVC Isquêmico/diagnóstico , AVC Isquêmico/epidemiologia , AVC Isquêmico/prevenção & controle , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle , Espectrometria de Massas em TandemRESUMO
BACKGROUND AND PURPOSE: Choline metabolism was suggested to play pathophysiological roles in nervous system and atherosclerosis development. However, little is known about the impacts of choline pathway nutrients and metabolites on poststroke cognitive impairment. We aimed to prospectively investigate the relationships between circulating choline, betaine, and trimethylamine N-oxide with cognitive impairment among acute ischemic stroke patients. METHODS: We derived data from CATIS (China Antihypertensive Trial in Acute Ischemic Stroke). Plasma choline, betaine, and trimethylamine N-oxide concentrations at baseline were measured in 617 participants. Cognitive impairment was evaluated using the Mini-Mental State Examination and the Montreal Cognitive Assessment. Reclassification and calibration of models with choline-related biomarkers were evaluated. RESULTS: Plasma choline and betaine were inversely associated with cognitive impairment. Compared with the lowest tertile, adjusted odds ratios of Mini-Mental State Examination-defined cognitive impairment for participants in the highest tertiles of choline and betaine were 0.59 (95% CI, 0.39-0.90) and 0.60 (95% CI, 0.39-0.92), respectively. In addition, both choline and betaine offered incremental predictive ability over the basic model with established risk factors, shown by increase in net reclassification improvement and integrated discrimination improvement. There were similar significant relationships between choline and betaine with cognitive impairment as defined by the Montreal Cognitive Assessment. However, plasma trimethylamine N-oxide was only associated with cognitive impairment evaluated using the Mini-Mental State Examination; the adjusted odds ratio was 1.33 (95% CI, 1.04-1.72) for each 1-SD increment of trimethylamine N-oxide. CONCLUSIONS: Patients with higher choline and betaine levels had lower risk of cognitive impairment after ischemic stroke, supporting promising prognostic roles of choline pathway nutrients for poststroke cognitive impairment.
Assuntos
Colina/metabolismo , Transtornos Cognitivos/metabolismo , AVC Isquêmico/terapia , Idoso , Anti-Hipertensivos/farmacologia , Isquemia Encefálica/diagnóstico , China , Colina/química , Cognição , Disfunção Cognitiva/etiologia , Feminino , Humanos , Hipertensão/terapia , Masculino , Metilaminas/metabolismo , Pessoa de Meia-Idade , Prognóstico , Método Simples-Cego , Acidente Vascular Cerebral/diagnóstico , Resultado do TratamentoRESUMO
BACKGROUND AND OBJECTIVES: Recent studies have suggested that plasma soluble dipeptidyl peptidase-4 (sDPP4) have important physiologic effects, which may influence the prognosis of ischemic stroke. Our study aimed to examine the relationship between plasma sDDP4 levels and long-term clinical outcomes among patients with acute ischemic stroke. METHODS: Secondary analysis was conducted among 3,564 participants (2,270 men and 1,294 women) from the China Antihypertensive Trial in Acute Ischemic Stroke with baseline measurement of plasma sDPP4 levels. We evaluated the associations between plasma sDPP4 levels and 2-year clinical outcomes using logistic regression and Cox regression models. We further investigated the predictive utility of sDPP4 by calculating net reclassification index and integrated discrimination improvement. RESULTS: The highest plasma sDPP4 quartile was associated with lower risk of cardiovascular events (hazard ratio [HR] 0.62, 95% confidence interval [CI] 0.45-0.87), recurrent stroke (HR 0.70, 95% CI 0.49-0.99), all-cause mortality (HR 0.62, 95% CI 0.44-0.87), stroke-specific mortality (HR 0.65, 95% CI 0.44-0.94), and poor functional outcomes (odds ratio 0.66, 95% CI 0.53-0.82) at 2 years compared with the lowest sDPP4 category in multivariable models. The addition of plasma sDPP4 to conventional risk factors model significantly improved risk prediction of all outcomes. DISCUSSION: In this study, we found that higher plasma sDPP4 levels in patients with acute ischemic stroke were associated with decreased risks of cardiovascular events, recurrent stroke, all-cause mortality, and poor functional outcomes after ischemic stroke. These findings suggest that plasma sDPP4 may be a potential prognostic marker for initial risk stratification in patients with acute ischemic stroke.
Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Anti-Hipertensivos/uso terapêutico , Biomarcadores , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , China/epidemiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Prognóstico , Fatores de RiscoRESUMO
BACKGROUND: Dynamic change of heart rate in the acute phase and clinical outcomes after intracerebral hemorrhage (ICH) remains unknown. We aimed to investigate the associations of heart rate trajectories and variability with functional outcome and mortality in patients with acute ICH. METHODS: This prospective study was conducted among 332 patients with acute ICH. Latent mixture modeling was used to identify heart rate trajectories during the first 72 h of hospitalization after ICH onset. Mean and coefficient of variation of heart rate measurements were calculated. The study outcomes included unfavorable functional outcome, ordinal shift of modified Rankin Scale score, and all-cause mortality. RESULTS: We identified 3 distinct heart rate trajectory patterns (persistent-high, moderate-stable, and low-stable). During 3-month follow-up, 103 (31.0%) patients had unfavorable functional outcome and 46 (13.9%) patients died. In multivariable-adjusted model, compared with patients in low-stable trajectory, patients in persistent-high trajectory had the highest odds of poor functional outcome (odds ratio 15.06, 95% CI 3.67-61.78). Higher mean and coefficient of variation of heart rate were also associated with increased risk of unfavorable functional outcome (P trend < 0.05), and the corresponding odds ratios (95% CI) comparing two extreme tertiles were 4.69 (2.04-10.75) and 2.43 (1.09-5.39), respectively. Likewise, similar prognostic effects of heart rate dynamic changes on high modified Rankin Scale score and all-cause mortality were observed. CONCLUSIONS: Persistently high heart rate and higher variability in the acute phase were associated with increased risk of unfavorable functional outcome in patients with acute ICH.
RESUMO
Fourier transform infrared spectroscopy (FTIR) can be used for the continuously on-line quantitative determination of the concentrations of several gas components in smoke gas. The process of acquiring accurate calibration of spectra is one of the most important steps in the quantitative analysis. In the present paper, a novel calibration technique was proposed and evaluated by the results of CO and HCl. Data obtained by this new technique were compared to those of conventional concentration-based calibration. The results showed that this calibration technique is feasible, and its reliability and validity were also confirmed. Further more, it has several other advantages, which will also be discussed here. Finally, the calibration problem that the substances are liquid at ambient temperature was solved by this technique.