scholarly journals Performance Characteristics and Clinical Value of the Lipoprotein-Associated Phospholipase A2 by an Enzymatic Kinetic Method

2019 ◽  
Vol 50 (3) ◽  
pp. 273-278
Author(s):  
Mengli Lu ◽  
Liying Lv

Abstract Objective To analyze the performance characteristics, stability, and clinical value of lipoprotein-associated phospholipase A2 (Lp-PLA2) using an enzymatic kinetic method. Methods The performance characteristics included reference intervals, precision, and accuracy. We assessed Lp-PLA2 stability by comparing Lp-PLA2 changes under different conditions. Lp-PLA2 was determined in the following groups: control individuals, patients with coronary heart disease (CHD), patients of different lipid subgroups within CHD, and patients with high total cholesterol (TC). Also, correlations between Lp-PLA2 and traditional cardiovascular risk factors were assessed. Results The mean (SD) reference interval of serum Lp-PLA2 activity was 451 (113) U per L with sex differences. Inter- and intra-assay precision revealed coefficients of variance (CVs) of 1.81% to 2.63% and 1.43% to 1.77%. The average bias was 0.33%. Lp-PLA2 activity was stable. In the CHD group, high-lipid subgroups, and high-TC group, Lp-PLA2 was elevated, and correlation was observed between Lp-PLA2 and traditional risk factors. Conclusion Lp-PLA2 activity has important clinical value in CHD.

Author(s):  
Lone G. M. Jørgensen ◽  
Ivan Brandslund ◽  
Per Hyltoft Petersen ◽  
Marta Stahl ◽  
Niels de Fine Olivarius

AbstractReference intervals are recommended for naturally occurring quantities and required in the evaluation of new components in order to provide clinically useful information.The aim of the present study is to present a method for selecting reference individuals for the determination of fasting venous plasma glucose (f-vPG) reference intervals and ways to determine if disease groups can share reference intervals with an ideal reference population.Reference subjects were randomly selected, eligibility was judged according to predetermined inclusion and exclusion criteria. Using the literature we selected risk indicators for diabetes mellitus (DM) and used these indicators to rule out high-risk individuals in order to obtain a reference distribution of f-vPG determined using individuals with low risk of DM. The distributions of f-vPG in the high-risk individuals was compared with that determined for the low-risk group. We then estimated the ability of the high-risk individuals to share the reference interval of the low risk individuals, and calculated the fraction that was outside this interval. Distributions were also investigated for linearity in the cumulated frequency rankit distribution of ln-values. The allowable difference between two reference limits could not exceed 0.375 times the population biological variation.Most risk indicators were powerful predictors of high f-vPG values. Subgroups with these risk indicators should not be included in the homogeneous ln-normally distributed reference distribution. Distributions of f-vPG concentrations in individuals with risk factors were not homogeneous and varying percentages of individuals were outside the reference distribution, having f-vPG greater than 7.0 mmol/l.We conclude that randomisation is only useful to recruit candidate reference subjects. To rule out subjects according to clinical risk factors for diabetes, it is necessary to identify a reference population with low risk of exhibiting increased f-vPG concentrations. This method may be used to validate a reference interval for a particular analyte with respect to an investigated disease, and to stratify risk factors of importance.


2019 ◽  
Vol 4 (3) ◽  
pp. 141-144
Author(s):  
Evelin Szabó ◽  
Zsolt Parajkó ◽  
Diana Opincariu ◽  
Monica Chițu ◽  
Nóra Raț ◽  
...  

Abstract Atherosclerosis is the elemental precondition for any cardiovascular disease and the predominant cause of ischemic heart disease that often leads to myocardial infarction. Systemic risk factors play an important role in the starting and progression of atherosclerosis. The complexity of the disease is caused by its multifactorial origin. Besides the traditional risk factors, genetic predisposition is also a strong risk factor. Many studies have intensively researched cardioprotective drugs, which can relieve myocardial ischemia and reperfusion injury, thereby reducing infarct size. A better understanding of abnormal epigenetic pathways in the myocardial pathology may result in new treatment options. Individualized therapy based on genome sequencing is important for an effective future medical treatment. Studies based on multiomics help to better understand the pathophysiological mechanism of several diseases at a molecular level. Epigenomic, transcriptomic, proteomic, and metabolomic research may be essential in detecting the pathological phenotype of myocardial ischemia and ischemic heart failure.


2020 ◽  
Vol 40 (12) ◽  
pp. 6987-6995
Author(s):  
NORBERT NECKEL ◽  
MARCO MICHAEL ◽  
DANIEL TROELTZSCH ◽  
JONAS WÜSTER ◽  
STEFFEN KOERDT ◽  
...  

2019 ◽  
Vol 14 (10) ◽  
pp. 1-8 ◽  
Author(s):  
Jackson Alun ◽  
Barbara Murphy

Loneliness and social isolation are increasingly being acknowledged as risk factors for both physical and mental health problems. Recent statistics demonstrate that loneliness and isolation are on the rise internationally, to the point of being classed as an epidemic. In this paper, the authors outline some of the recent research linking loneliness and isolation to significant chronic diseases such as cardiovascular disease and type II diabetes; mental health disorders such as anxiety and depression; cognitive disorders and dementia. Isolation has also been shown to compromise recovery after acute cardiac events, being associated with increased hospital readmission and premature death. Indeed, isolation has now been identified as a risk factor equivalent in effect to traditional risk factors such as smoking, hypertension and obesity. While distinguishing between objective and subjective indicators of isolation, the authors highlight the complexity of this phenomenon, both in terms of definition and measurement, as well as the interplay between subjective and objective indicators. Important clinical implications for health professionals working with cardiac patients are also proposed, in terms of screening for isolation, and possible interventions to support patients at risk of isolation. The aim of the current article is to emphasise the importance of acknowledging loneliness and isolation as key risk factors requiring urgent attention, both in research and in clinical practice.


Author(s):  
O E Okosieme ◽  
Medha Agrawal ◽  
Danyal Usman ◽  
Carol Evans

Background: Gestational TSH and FT4 reference intervals may differ according to assay method but the extent of variation is unclear and has not been systematically evaluated. We conducted a systematic review of published studies on TSH and FT4 reference intervals in pregnancy. Our aim was to quantify method-related differences in gestation reference intervals, across four commonly used assay methods, Abbott, Beckman, Roche, and Siemens. Methods: We searched the literature for relevant studies, published between January 2000 and December 2020, in healthy pregnant women without thyroid antibodies or disease. For each study, we extracted trimester-specific reference intervals (2.5–97.5 percentiles) for TSH and FT4 as well as the manufacturer provided reference interval for the corresponding non-pregnant population. Results: TSH reference intervals showed a wide range of study-to-study differences with upper limits ranging from 2.33 to 8.30 mU/L. FT4 lower limits ranged from 4.40–13.93 pmol/L, with consistently lower reference intervals observed with the Beckman method. Differences between non-pregnant and first trimester reference intervals were highly variable, and for most studies the TSH upper limit in the first trimester could not be predicted or extrapolated from non-pregnant values. Conclusions: Our study confirms significant intra and inter-method disparities in gestational thyroid hormone reference intervals. The relationship between pregnant and non-pregnant values is inconsistent and does not support the existing practice in some laboratories of extrapolating gestation references from non-pregnant values. Laboratories should invest in deriving method-specific gestation reference intervals for their population.


Angiology ◽  
2021 ◽  
pp. 000331972098459
Author(s):  
Yao-dong Ding ◽  
Yu-qiang Pei ◽  
Rui-Wang ◽  
Jia-xin Yang ◽  
Ying-xin Zhao ◽  
...  

We investigated the association between plasma microRNA (miR)-204 and coronary artery calcification (CAC) in patients with type 2 diabetes mellitus (T2DM). We consecutively enrolled 179 individuals with T2DM who underwent coronary computed tomography at Anzhen Hospital from January 2015 to September 2016. The CAC score (CACS) was expressed in Agatston units and >10 Hounsfield units were defined as CAC-positive status. Significant CAC was observed in 98 (54.7%) patients. Plasma miR-204 levels (relative expression) were significantly lower in patients with significant CAC than controls (1.001 ± 0.100 vs 0.634 ± 0.211, P < .001). Plasma miR-204 levels were also negatively correlated with the glycosylated hemoglobin A1c (HbA1c) level (r = −0.702, P < .001), CACS (r = −0.710, P < .001), and the United Kingdom Prospective Diabetes Study (UKPDS) score (r = −0.355, P < .001). After multivariate logistic analyses, plasma miR-204 levels were still significantly and independently associated with the presence of CAC (odds ratio = 0.103, CI = 0.018-0.583, P < .001) after adjustment for conventional risk factors. Receiver operating characteristic curve analysis showed that plasma miR-204 levels can predict the severity and extent of CAC, and the specificity was higher than that of the traditional risk factors UKPDS score and HbA1c. In conclusion, the downregulation of miR-204 was independently associated with CAC in patients with T2DM.


2020 ◽  
Vol 4 (02) ◽  
pp. 104-110
Author(s):  
Fabiola B. Sozzi ◽  
Marta Belmonte ◽  
Marco Schiavone ◽  
Ciro Canetta ◽  
Rakesh Gupta ◽  
...  

AbstractAlthough substantial progress has been made toward improving gender- and sex-specific cardiovascular disease (CVD) management and outcomes, contemporary reports indicate a persistent knowledge gap with regard to optimal risk-stratification and management in female cardiac heart disease (CHD) patients. Prominent patient and system delays in diagnosing CHD are, in part, due to the limited awareness for the latent CVD risk in women, a lack of sex-specific thresholds within clinical guidelines, and subsequent limited performance of contemporary diagnostic approaches in women. Several traditional risk factors for CHD affect both women and men. But other factors can play a bigger role in the development of heart disease in women. In addition, little is known about the influence of socioenvironmental and contextual factors on gender-specific disease manifestation and outcomes. It is imperative that we understand the mechanisms that contribute to worsening risk factors profiles in young women to reduce future atherosclerotic CVD morbidity and mortality. This comprehensive review focuses on the novel aspects of cardiovascular health in women and sex differences as they relate to clinical practice and prevention, diagnosis, and treatment of CVD. Increased recognition of the prevalence of traditional cardiovascular risk factors and their differential impact in women, as well as emerging nontraditional risk factors unique to or more common in women, contribute to new understanding mechanisms, leading to worsening outcome for women.


2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
F Zhu ◽  
B Arshi ◽  
E Aribas ◽  
MA Ikram ◽  
MK Ikram ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): the Erasmus Medical Center and Erasmus University Rotterdam; the Netherlands Organization for Health Research and Development (ZonMw); Purpose To evaluate the sex-specific predictive value of two cardiac biomarkers; N-terminal pro B-type natriuretic peptide (NT-proBNP) and high sensitivity cardiac troponin T (hs-cTnT), alongside traditional cardiovascular risk factors, for 10-year cardiovascular risk prediction in general population. Methods A total of 5430 participants (mean age 68.1 years; 59.9% women) free of cardiovascular disease (CVD), with blood sample measurements between 1997 and 2001 were included. We developed a ‘base’ model using cardiovascular risk factors used in the Pooled Cohort Equation (includes age, sex, systolic blood pressure, treatment of hypertension, total and high-density lipoprotein cholesterol levels, smoking, and diabetes) and then extended the ‘base’ model with NT-proBNP or hs-cTnT. These models were developed for coronary heart disease (CHD), stroke, and heart failure (HF) and also for composite CVD outcomes. To evaluate biomarkers’ added predictive value, c-statistic, and net reclassification improvement index (NRI) for events and non-events were calculated. NRI was calculated using cutoffs of 5%, 7.5% and 20% to categorize participants as low, borderline, intermediate, or high risk. Results Adding NT-proBNP to the ‘base’ model significantly improved c-statistic for all outcomes (increases ranged between 0.012-0.047), with the largest improvement in HF [0.026 (95% CI, 0.013, 0.040) for women and 0.047 (95% CI, 0.026, 0.069) for men]. Adding hs-TnT to ‘base’ model increased the c-statistic for CHD in women by 0.040 (95% CI, 0.013, 0.067) and for HF in men by 0.032 (95% CI, 0.005, 0.059). Improvments in reclassification by both biomarkers were mostly limited to modest improvemetns in reclassification of non-events [largest non-event NRI for global CVD in women (NT-proBNP: 11.8%; hs-cTnT: 10.5%) and for HF in men (NT-proBNP: 9.6%; hs-cTnT: 8.4%)]. Conclusion NT-proBNP improved model performance for prediction of all cardiovascular outcomes, in particular for HF, beyond traditional risk factors for both women and men. Hs-cTnT showed modest added predictive value beyond traditional risk factors for CHD among women and for HF among men. Imropovements in reclassification by both biomarkers were modest and not clinically relevant. Improvements of 10-year risk predictions Events Adding NT-proBNP Adding troponin T Delta c-statistic* Event NRI, % Non-event NRI, % Delta c-statistic* Event NRI, % Non-event NRI, % WomenASCVD Global CVD 0.012 (0.004, 0.020) 0.018 (0.010, 0.026) -1.7 (-5.0, 1.5)-0.8 (-3.8, 2.2) 5.4 (3.5, 7.2)11.8 (9.6, 14.1) 0.028 (0.009, 0.048)0.025 (0.009, 0.040) -0.4 (-7.1, 6.2)2.9 (-2.4, 8.3) 6.9 (3.9, 9.9)10.5 (7.3, 13.8) MenASCVD Global CVD 0.016 (0.005, 0.027)0.023 (0.012, 0.033) 0.7 (-2.3, 3.7)-0.3 (-3.0, 2.4) 5.2 (3.2, 7.2)7.2 (4.9, 9.4) 0.007 (-0.002, 0.016)0.011 (0.000, 0.021) -1.1 (-5.0, 2.7)-1.6 (-6.0, 2.8) 4.0 (1.2, 6.9)6.4 (3.1, 9.7) ASCVD comprises coronary heart disease and stroke; Global CVD comprises coronary heart disease, stroke and heart failure.


2021 ◽  
Author(s):  
K Aaron Geno ◽  
Matthew S Reed ◽  
Mark A Cervinski ◽  
Robert D Nerenz

Abstract Introduction Automated free thyroxine (FT4) immunoassays are widely available, but professional guidelines discourage their use in pregnant women due to theoretical under-recoveries attributed to increased thyroid hormone binding capacity and instead advocate the use of total T4 (TT4) or free thyroxine index (FTI). The impact of this recommendation on the classification of thyroid status in apparently euthyroid pregnant patients was evaluated. Methods After excluding specimens with thyroid autoantibody concentrations above reference limits, thyroid-stimulating hormone (TSH), FT4, TT4, and T-uptake were measured on the Roche Cobas® platform in remnant clinical specimens from at least 147 nonpregnant women of childbearing age and pregnant women at each trimester. Split-sample comparisons of FT4 as measured by the Cobas and equilibrium dialysis were performed. Results FT4 decreased with advancing gestational age by both immunoassay and equilibrium dialysis. TSH declined during the first trimester, remained constant in the second, and increased throughout the third, peaking just before delivery. Interpretation of TT4 concentrations using 1.5-times the nonpregnant reference interval classified 13.6% of first trimester specimens below the lower reference limit despite TSH concentrations within trimester-specific reference intervals. Five FTI results from 480 pregnant individuals (about 1.0%) fell outside the manufacturer’s reference interval. Conclusions Indirect FT4 immunoassay results interpreted in the context of trimester-specific reference intervals provide a practical and viable alternative to TT4 or FTI. Declining FT4 and increasing TSH concentrations near term suggest that declining FT4 is not an analytical artifact but represents a true physiological change in preparation for labor and delivery.


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