The role of the TERC-63G>A and TERT-1327C>T telomerase polymorphisms in the study of men with acute coronary syndrome

AIM

Telomerase is a ribonucleoprotein that maintains telomere length. Telomeres and telomerase are involved in cellular ageing and have been connected to some ageing related diseases, like cardiovascular disease. Telomerase dysfunction could be the main underlying mechanism in this connection but this point is still unclear. The aim of this article is to investigate the possible influence of cellular ageing, measured by two telomerase polymorphisms, TERC-63G>A (rs2293607) and TERT-1327C>T (rs2735940), on the whole spectrum of acute coronary artery disease (CAD).

METHODS

We studied 150 middle aged men admitted for an acute coronary syndrome (ACS). Cardiovascular risk factors prevalence was collected at admission. Severity variables analyzed were Killip class and number of vessels affected. Telomerase polymorphisms were studied by real time PCR in DNA samples extracted from peripheral blood leukocytes. Clinical follow-up had been developed for more than 600 days and a prognostic combined event was defined.

RESULTS

C allele of TERT polymorphism was more prevalent among hypertensive patients (OR: 3.19; 95% CI: 1.37-7.42; P=0.006). None of polymorphisms showed any prognostic value or relation to CAD severity.

CONCLUSION

Telomerase dysfunction could be involved in hypertension prevalence. This finding could support new screening strategies in high risk population. The two telomerase polymorphisms analyzed did not show any prognostic value or connection to CAD severity. However, further studies are required to determine the molecular mechanisms responsible for cellular ageing in ACS.

An individualized pre-operative blood saving protocol can increase pre-operative haemoglobin levels and reduce the need for transfusion in elective total hip or knee arthroplasty

We have prospectively evaluated the efficacy of an individualized pre-operative blood saving protocol in elective total hip arthroplasty (THA) or total knee arthroplasty (TKA). The primary aim was to obtain a pre-operative haemoglobin (Hb) level of > or =14 g dL(-1). A reduction in requirements for allogeneic transfusion was considered the second aim. Several strategies are available for increasing pre-operative Hb levels and reducing red blood cell (RBC) transfusions following THA or TKA, but the success of these programmes depends on selecting the most appropriate treatment for each patient. Three hundred and five patients with an indication of elective THA or TKA were individually assigned to the following strategies according to Hb and ferritin levels and medical conditions: (a) no pre-operative intervention, (b) oral iron therapy, (c) intravenous (i.v.) iron therapy, (d) recombinant human erythropoietin alpha with i.v. iron and (e) pre-operative autologous donation (PAD) plus oral iron. Eighty-two percent of the patients reached a pre-operative Hb level of > or =14 g dL(-1) compared with 62% of patients with Hb levels of > or =14 g dL(-1) at the baseline visit. Treatment with PAD showed a significant reduction in the pre-operative Hb levels. The rate of RBC transfusion was 18.8% compared with 31.5% of matched historic group (P < 0.001). In conclusion, all patients scheduled to undergo THA or TKA should be candidates for an individualized pre-operative blood salvage programme.

Tubes for pretransfusion testing should be collected by blood bank staff and hand labelled until the implementation of new technology for improved sample labelling. Results of a prospective study

BACKGROUND AND OBJECTIVES

The greatest risk in transfusion medicine is actually human error, resulting in the use of the incorrect blood component. The aim of our study was to identify and evaluate the risk factors involved in the collection and labelling of pretransfusion blood samples.

MATERIAL AND METHODS

We prospectively evaluated 6446 samples submitted to the blood bank for pretransfusion testing. Inappropriate samples were classified as 'mislabelled' or 'miscollected'. After 4 months of study, an educational approach was taken.

RESULTS

The frequency of inappropriately labelled samples was 6.45%. Such samples were associated with the use of addressograph labels (vs. hand-written labels) [23.4% vs. 1.4%, P < 0.0001], collection by clinical staff (vs. blood bank staff) [8.8% vs. 2.1%, P = 0.001] and emergency situations (vs. routine sampling) [10.1% vs. 6.1%, P = 0.005]. Following educational intervention, the percentage of inappropriately labelled samples decreased from 7.3% (pre-educational) to 5.8% (post-educational), P = 0.005.

CONCLUSION

Ongoing monitoring and analysis of labelling and collection should be mandatory in order to improve the safety of transfusion.

Hyperhomocysteinemia is a risk factor of recurrent coronary event in young patients irrespective to the MTHFR C677T polymorphism

Despite the well-known pro-coagulant effect of hyperhomocysteinemia, data is limited regarding the result on recurrent coronary event (RCE) in young people. One hundred and forty patients <55 years old with a first acute coronary syndrome (ACS) were prospectively followed for a mean (+/-S.D.) follow-up of 49+/-14 months in order to investigate the relationship between homocysteine levels (tHcy) at admission and the incidence of RCE. The tHcy values were divided into quartiles to examine their relationship with end points. Furthermore, we determined the effect of C677T methylene tetrahydrofolate reductase (MTHFR) polymorphism, as well as other risk factors for developing a RCE. The median plasma homocysteine concentration was 9.6 mumol/L (interquartile range, 3.7). In the screening of MTHFR C677T polymorphism in patients with ACS, the T allele frequency was 0.4 and the genotype frequency distributions were in Hardy-Weinberg equilibrium. At time of final evaluation, 49 (35%) of the 140 valuable patients had developed a RCE. Increasing numbers of RCE were observed for increasing quartiles of tHcy according to Kaplan-Meier survival (Log-rank test=0.0092). The MTHFR C677T polymorphism was not associated with an increased incidence of RCE. In multivariate analysis, the variables independently associated with a higher risk of RCE were age older than 45 years [HR=2.7; (95% CI, 1.3-6.1); p=0.030], body mass index more than 25 [HR=2.6; (95% CI, 1.1-5.9); p=0.034] and tHcy levels into quartile 4 (tHcy>12.37 mumol/L) [HR=2.5; (95% CI, 1.1-4.7); p=0.04]. Elevated plasma homocysteine level at admission is an independent risk factor for RCE after the first episode of ACS in young patients irrespective of the status of MTHFR C677T.