Agnieszka Kondracka

Genetic determinants of platelet reactivity during acetylsalicylic acid therapy in diabetic patients: evaluation of 27 polymorphisms within candidate genes

Summary.  Aims: Decreased platelet responsiveness to acetylsalicylic acid (ASA) reported previously in diabetic patients could be attributed to patient‐based, clinical, genetic and cellular factors. The objective of the present study was to investigate the effect of the genomic polymorphism on the platelet reactivity in diabetic patients treated with ASA. Methods and results: The study cohort consisted of 295 Caucasians with diabetes type 2 who had been taking ASA tablets at the dose of 75 mg per day for at least 3 months for primary or secondary prevention of myocardial infarction (MI). Platelet reactivity analyzes were performed using VerifyNow ASA and PFA‐100 assays. Genotyping for the selected 27 single nucleotide polymorphisms (SNPs) within 19 genes was performed using a Sequenom iPLEX platform. The results indicate that the statistically significant differences in platelet reactivity were observed in the PFA‐100 assay for SNPs in following genes: TXBA2R (rs1131882), ADRA2A (rs4311994), PLA2G7 (rs7756935) and 9p21.3 (rs10120688) (P = 0.02, P = 0.03, P = 0.02, P = 0.03, respectively, all significance levels corrected for multiple comparisons). When using the VerifyNow ASA test, a weak nominal statistical significance (i.e. before multiple comparison testing) was observed for two SNPs in the GPVI gene: rs1671152 and rs1613662 [P = 0.025 (0.5) for both SNPs, corrected for multiple comparisons test]. Conclusions: The results from the present study suggest that the four analyzed genes may contribute to platelet reactivity measured with the PFA‐100 assay in the diabetic population treated with ASA.

DIAGNOSTIC UTILITY OF PLEURAL FLUID AND SERUM MARKERS IN DIFFERENTIATION BETWEEN MALIGNANT AND NON-MALIGNANT PLEURAL EFFUSIONS

Study objectiveTo evaluate the diagnostic value of four different tumor markers: cancer antigen 125 (CA-125), carcinoembryonic antigen (CEA), cytokeratin 19 fragment (CYFRA 21-1) and neuron specific enolase (NSE) in patients with malignant and non-malignant pleural effusion.Material and methodsOne hundred and two patients with pleural effusion treated in the University Hospital in Warsaw between 2001 and 2003 were studied. They underwent an extensive, diagnostic work-up in order to determine the pleural effusion etiology. Patients with known pleural fluid etiology were labeled as the study group and submitted for further analysis. Pleural fluid and serum samples for CA-125, CEA, CYFRA 21-1 and NSE measurements were collected during the first thoracentesis, centrifuged, and frozen until further use. Pleural fluid and serum concentration of tumor markers were assessed by electrochemiluminescence methods using commercial kits.Results74 patients (32 M, 42 F; mean age 65 ± 14 years) composed the final study group. Exudative pleural effusion was found in 62 patients; of these 36 were malignant (48.6% of all effusions), 20 parapneumonic (or pleural empyema), and 6 tuberculous. In 12 patients, pleural transudate was diagnosed. The highest diagnostic sensitivity for malignant pleural effusion was found for NSE (94.4% and 80.6% in the pleural fluid and serum, respectively). However, the specificity of NSE measurement was relatively low (36.1% and 47.4% in pleural fluid and serum, respectively). The most specific markers of malignant pleural fluid etiology were pleural fluid CYFRA 21-1 and CEA levels (92.1% and 92.1%, respectively). CA-125 was found to be the most specific serum marker of pleural malignancies (78.9%). The AUC for combined pleural markers was 0.89, combined serum markers 0.82, combined ratio pleural/serum markers 0.88.ConclusionsThere are significant differences between the diagnostic value of various pleural fluid and serum markers. Overall, pleural fluid markers are superior to serum markers in determining the pleural fluid etiology. A combination of two or more tumor markers may help improve their diagnostic accuracy. Pleural fluid and serum measurements of different tumor markers play a limited role in the differentiation between malignant and non-malignant pleural effusions.

Effect of ASA dose doubling versus switching to clopidogrel on plasma inflammatory markers concentration in patients with type 2 diabetes and high platelet reactivity: The AVOCADO study

BACKGROUND The aim of the study was to compare the effects of 2 strategies of antiplatelet treatment (i.e., 150 mg ASA vs. 75 mg clpoidogrel) on plasma level of inflammatory markers in type 2 diabetes mellitus (T2DM) patients with high platelet reactivity (HPR). METHODS Study cohort consisted of 304 T2DM patients on chronic ASA therapy (75 mg per day) participating in the Aspirin Versus/Or Clopidogrel in Aspirin-resistant Diabetics inflammation Outcomes (AVOCADO) study. Patients with HPR defined as Platelet Function Analyzer (PFA)-100 collagene/epinephrine closure time (CEPI-CT) < 193 s (n = 80) were randomized to 150 mg of ASA or 75 mg of clopidogrel in 2:3 ratio, respectively. Concentrations of the selected inflammatory markers, including tumor necrosis factor (TNF)-α, interleukin (IL)-6, solubleCD40 ligand (sCD40L), and high sensitivity C-reactive protein (hsCRP), were measured and compared in both treatment groups before and after 8 weeks of treatment in both groups. RESULTS Out of 234 patients included into final analysis, the total of 34.2% (n = 80) patients displayed HPR, of which 14.1% (n = 33) were randomized into 150 mg of ASA group and 20.1% (n = 47) into 75 mg of clopidogrel group. Treatment with clopidogrel was a positive predictor (stepwise multiple regression analysis) of reduction of sCD40L concentration (odds ratio [OR] 4.15; p = 0.013), while treatment with 150 mg ASA was a positive predictor of reduction of IL-6 concentration (OR 4.38; p = 0.033). There was no statistically significant differences between clopidogrel and ASA 150 mg treatment in respect to predictive value for decreased hsCRP concentrations or increased TNF-α concentrations. CONCLUSIONS Increasing the dose of ASA from 75 mg to 150 mg daily or switching ASA 75 mg to clopidogrel 75 mg daily may reduce concentrations of some inflammatory markers (in particular hsCRP, IL-6 and CD40L) in T2DM patients with HPR treated previously with 75 mg of ASA.

Predictors of high platelet reactivity during aspirin treatment in patients with type 2 diabetes

BACKGROUND Diabetes mellitus type 2 (DM2) is associated with high platelet reactivity both in patients who do not receive antiplatelet drugs and in those treated with acetylsalicylic acid (ASA). The pathomechanism of this phenomenon has not been fully understood. AIM 1. To evaluate variability of platelet reactivity in patients with DM2 treated with oral antidiabetic drugs and receiving chronic ASA therapy. 2. To identify independent predictors of high platelet reactivity during ASA therapy in patients with DM2. METHODS We studied 171 patients with DM2 treated with oral antidiabetic drugs and receiving long-term treatment with 75 mg of ASA daily, selected among the participants of the prospective AVOCADO study. Platelet function was simultaneously evaluated using 4 methods: 1. measurement of serum thromboxane B2 (TXB2) concentration; 2. measurement of urinary 11-dehydrothromboxane B2 (11-dhTXB2) concentration; 3. VerifyNow® automated analyser; 4. PFA-100® automated analyser.High platelet reactivity was defined as at least 3 of the following criteria: 1. serum TXB2 concentration in the upper quartile;2. urinary 11-dhTXB2 concentration in the upper quartile; 3. value ≥ 550 aspirin reaction units (ARU) by VerifyNow®;4. collagen-epinephrine closure time (CEPI-CT) below median of readings other than 300 s by PFA-100®. In all patients, DM2 control was evaluated, insulin resistance was measured using HOMA-IR, and routine laboratory tests were performed, including full blood count, renal function parameters, and inflammation markers. RESULTS Mean patient age was 67.8 years, and median duration of DM2 was 5 years. We found poor agreement between different tests of platelet function. ARU ≥ 550 (VerifyNow®) was found in 14.0% of patients, and CEPI-CT below median of readings other than 300 s (PFA-100®) was found in 32.8% of patients. Our criteria of high platelet reactivity were met by 9.9% of patients. In multivariate logistic regression analysis, independent predictors of high platelet reactivity despite ASA therapy included chronic heart failure, current smoking, and higher leukocyte count. CONCLUSIONS 1. Patients with DM2 are characterised by large variability of platelet reactivity, with little agreement between various methods. 2. Smoking, chronic heart failure, and subclinical inflammation may be associated with high platelet reactivity in patients with DM2 treated with ASA.

Younger age, higher body mass index and lower adiponectin concentration predict higher serum thromboxane B2 level in aspirin-treated patients with type 2 diabetes: an observational study

BackgroundEvidence from the literature suggests diminished acetylsalicylic acid (ASA) treatment efficacy in type 2 diabetes (DM2). High on-aspirin platelet reactivity (HAPR) in DM2 has been linked to poor glycemic and lipid control. However, there are no consistent data on the association between HAPR and insulin resistance or adipose tissue metabolic activity. The aim of this study was to assess the relationship between laboratory response to ASA and metabolic control, insulin resistance and adipokines in DM2.MethodsA total of 186 DM2 patients treated with oral antidiabetic drugs and receiving 75 mg ASA daily were included in the analysis. Response to ASA was assessed by measuring serum thromboxane B2 (TXB2) concentration and expressed as quartiles of TXB2 level. The achievement of treatment targets in terms of glycemic and lipid control, insulin resistance parameters (including Homeostatic Model Assessment-Insulin Resistance, HOMA-IR, index), and serum concentrations of high-molecular weight (HMW) adiponectin, leptin and resistin, were evaluated in all patients. Univariate and multivariate logistic regression analyses were performed to determine the predictive factors of serum TXB2 concentration above the upper quartile and above the median.ResultsSignificant trends in age, body mass index (BMI), HOMA-IR, HMW adiponectin concentration, C-reactive protein concentration and the frequency of achieving target triglyceride levels were observed across increasing quartiles of TXB2. In a multivariate analysis, only younger age and higher BMI were independent predictors of TXB2 concentration above the upper quartile, while younger age and lower HMW adiponectin concentration were predictors of TXB2 concentration above the median.ConclusionsThese results suggest that in DM2, the most important predictor of HAPR is younger age. Younger DM2 patients may therefore require total daily ASA doses higher than 75 mg, preferably as a twice-daily regimen, to achieve full therapeutic effect. Higher BMI and lower HMW adiponectin concentration were also associated with less potent ASA effect. This is the first study to demonstrate an association of lower adiponectin concentration with higher serum TXB2 level in patients treated with ASA.

Effect of common single-nucleotide polymorphisms in acetylsalicylic acid metabolic pathway genes on platelet reactivity in patients with diabetes

Background Platelet reactivity in patients on acetylsalicylic acid (ASA) therapy can be influenced by physiological or pathological conditions affecting ASA pharmacokinetics or pharmacodynamics. The mechanism of such variability in the therapeutic response to ASA, particularly in diabetic patients, is poorly understood. The rate of elimination of ASA and its metabolite, salicylic acid (SA), is likely a major factor determining drug efficacy. The objective of this study was to investigate the effect of genetic polymorphisms in the selected candidate genes within the ASA metabolic pathway on the platelet reactivity and concentration of ASA and thromboxane A2 (TxA2) metabolites in a population of patients with type 2 diabetes mellitus (T2DM). Material/Methods The study cohort consisted of 287 Caucasians with T2DM who had been taking ASA tablets at the dose of 75 mg per day for at least 3 months. Platelet reactivity analyses were performed using VerifyNow Aspirin and PFA-100 assays. The measured ASA metabolite included salicylic acid (ASA), and TxA2 metabolites included serum TxB2 and urinary 11-dh-TxB2. Genotyping for the selected 18 single-nucleotide polymorphisms (SNPs) within 5 genes of the ASA metabolic pathway was performed using a Sequenom iPLEX platform. Results No statistically significant association was observed between the investigated SNPs genotypes, platelet reactivity, and measured metabolites in the investigated cohort of patients. Conclusions The results of our study failed to confirm that the selected variants in the genes within the ASA metabolic pathway might contribute to platelet reactivity in a diabetic population treated with ASA.

The morning and late‐night salivary cortisol ranges for healthy women may be used in pregnancy

The diagnosis of adrenal dysfunction in pregnancy and in women taking oral contraceptives remains a diagnostic challenge. Salivary cortisol seems to be a useful tool for the diagnosis of Cushings syndrome and adrenal insufficiency. However, the changes in salivary cortisol concentration in healthy pregnancy are not clearly defined.

LC-MS/MS improves screening towards 21-hydroxylase deficiency

Abstract Basal serum 17OHP measurement remains the first screening step for nonclassic congenital adrenal hyperplasia (NCCAH) and the accuracy of the test is of high value. The aim of this study was to compare the accuracy of immunoassays to LC-MS/MS in the assessment of serum 17OHP and androgens concentration in women with hyperandrogenism and controls. 17OHP, total testosterone, androstendione and DHEA-S were measured in 39 women with clinically and/or biochemically evident hyperandrogenism and in 29 age-matched controls without clinical hyperandrogenism. 17OHP and androgens were measured by immunoassays and by LC-MS/MS. In patients group median 17OHP level measured by immunoassays was significantly higher compared to LC-MS/MS (5.49 nmol/l-ELISA NovaTec® and 3.57 nmol/l-ELISA DRG® versus 1.56 nmol/l-LC-MS/MS p < 0.0001) as well as in the control group (2.58 nmol/l-ELISA DRG® versus 1.14 nmol/l-LC-MS/MS p < 0.0001). Additional, unnecessary diagnostic procedures explaining elevated 17OHP level were undertaken in 85% of patients when NovaTec® test was used, in 50% when ELISA DRG® and in none when LC-MS/MS method was applied. Total testosterone, androstendione and DHEA-S concentrations in the patients and the controls assessed by the immunoassays were also significantly higher compared to LC-MS/MS. LC-MS/MS is more reliable diagnostic tool in the measurement of serum 17OHP and androgens concentrations compared to immunoassays in women with hyperandrogenism.

Lack of effect of common single nucleotide polymorphisms in leukotriene pathway genes on platelet reactivity in patients with diabetes.

The aim of the present study was to investigate the effect of genetic polymorphisms in candidate genes within the leukotriene (LT) pathway on platelet reactivity and the concentration of selected LTs in diabetic patients treated with acetylsalicylic acid (ASA). The study cohort consisted of 287 Caucasians with type 2 diabetes who had received treatment with ASA tablets (75 mg/day) for at least three months. Platelet reactivity analyses were performed using VerifyNow aspirin and PFA‑100 assays. The measured LTs included leukotriene B4 (LTB4) and leukotriene E4 (LTE4). Genotyping for the selected 25 single nucleotide polymorphisms (SNPs) within six genes of the LT pathway was performed using a Sequenom iPLEX platform. No statistically significant association was observed between the investigated SNP genotypes, platelet reactivity and measured LTs in the patient cohort. The results of our study suggest that certain polymorphisms of the LT pathway are not associated with altered platelet reactivity and the measured LTs in diabetic patients treated with ASA.

Do statins influence platelet reactivity on acetylsalicylic acid therapy in patients with type 2 diabetes

BACKGROUND Type 2 diabetes (T2DM) patients are at increased risk of cardiovascular events despite long-term acetylsalicylic acid (ASA) therapy. This study was performed to establish the prevalence of high platelet reactivity (HPR) on ASA in T2DM and to identify its predictors. METHODS The study included 185 T2DM on chronic ASA therapy and to assess platelet reactivity during long-term ASA therapy, we applied the point-of-care method VerifyNow(®) aspirin test (Accumetrics, San Diego, CA, USA). RESULTS Compared with the low platelet reactivity (LPR) group, patients with HPR had higher triglyceride levels (145 vs. 118 mg/dL, p = 0.041), were less frequently treated with statins (57.1% vs. 75.3%; p = 0.038) and tumor necrosis factor-alpha (TNF-α) concentrations were higher (2.15 vs. 1.74 pg/mL; p = 0.052). In a multivariate analysis only statin therapy (OR 0.375; 95% CI 0.15-0.91; P = 0.030) and lower concentrations of TNF-α (for each 1.0 pg/ml: or 1.3; 95% ci 1.00-1.72; p = 0.046) were predictive of LPR. CONCLUSIONS Our study provides indirect evidence that the beneficial effect of statins on platelet activity may be related to their non-lipid-mediated, pleiotropic mechanisms of action. This might have been partly related to decreased platelet reactivity in patients receiving statin therapy. In our study in patients with T2DM, platelet reactivity on ASA therapy measured with VerifyNow(®) was associated with TNF-α concentrations and statin therapy. These results may imply a role for subclinical systemic inflammation and a beneficial effect of statins in the development of HPR in T2DM.