Depression and cognitive deficits in geriatric schizophrenia

Objective

Past reports have found patients with comorbid depression and schizophrenia spectrum disorders exhibit greater deficits in memory and attention compared to schizophrenia spectrum disorder patients without depressive symptoms. However, in contrast to younger schizophrenia patients, the few past studies using cognitive screens to examine the relationship between depression and cognition in inpatient geriatric schizophrenia have found that depressive symptomatology was associated with relatively enhanced cognitive performance. In the current study we examined the relationship between depressive symptoms and cognitive deficits in geriatric schizophrenia spectrum disorder patients (n = 71; mean age = 63.7) on an acute psychiatric inpatient service.

Method

Patients completed a battery of cognitive tests assessing memory, attention and global cognition. Symptom severity was assessed via the PANSS and Calgary Depression Scale for Schizophrenia.

Results

Results revealed that geriatric patients' depression severity predicted enhancement of their attentional and verbal memory performance. Patients' global cognitive functioning and adaptive functioning were not associated with their depression severity.

Conclusion

Contrary to patterns typically seen in younger patients and non-patient groups, increasing depression severity is associated with enhancement of memory and attention in geriatric schizophrenia spectrum disorder patients. Also, diverging from younger samples, depression severity was unassociated with patients adaptive and global cognitive functioning.     

Maladie cœliaque et accidents vasculaires cérébraux ischémiques

Introduction

Neurological manifestations of celiac disease are various. An association with ischemic stroke is not common and has not been well documented. We report two cases.

Observations

The first patient had experienced several transient ischemic strokes in the past 2 years and then had an acute ischemic stroke involving the territory of the right posterior cerebral artery. Investigations revealed celiac disease with no other recognizable etiology. The clinical course was marked by persistent visual aftereffects, but no new vascular event. The second patient had been followed since 1998 for celiac disease confirmed by pathology and serology tests. She was on a gluten-free diet. The patient had an ischemic stroke involving the territory of the left middle cerebral artery. Apart from a positive serology for celiac disease and iron deficiency anemia, the etiological work-up was negative.

Discussion

The mechanisms of vascular involvement in celiac disease are controversial. The most widely incriminated factor is autoimmune central nervous system vasculitis, in which tissue transglutaminase, the main auto-antigen contributing to maintaining the integrity of endothelium tissue, plays a major role. Other mechanisms are still debated, mainly vitamin deficiency.

Conclusion

Being a potentially treatable cause of ischemic stroke, celiac disease must be considered as a potential etiology of stroke of unknown cause, particularly in young patients, and even without gastrointestinal manifestations.     

Circulating tissue factor positive microparticles in patients with acute recurrent deep venous thrombosis

Introduction

Circulating tissue factor positive microparticles (MPTF) were reported in a wide range of diseases with thrombotic tendency. Though D-dimer assay had a high negative predictive value for deep venous thrombosis (DVT) recurrence, there are currently no reliable positive predictors for recurrent DVT. We therefore quantified MPTF in patients with acute recurrent DVT to determine whether MPTF levels could be used to predict recurrent DVT.

Materials and Methods

Microparticles (MPs) were isolated from plasma of initial DVT patients (n = 25), recurrent DVT patients (n = 25) and sex- and age-matched healthy individuals (n = 25), stained with annexin V, cell-specific monoclonal antibodies (MoAbs) and a MoAb directed against tissue factor (TF), and analyzed by flow cytometry. We also determined the plasma procoagulant activity with a Human TF Chromogenic Activity Assay Kit.

Results

We found total MPTF to be elevated in recurrent DVT patients versus normal individuals (P = 0.001). The number of monocyte-derived MPTF in both initial and recurrent DVT was higher than in normal individuals (P < 0.01, respectively). The platelet and endothelial cell derived MPTF in recurrent DVT were significantly increased relative to other MPTF (P < 0.05), although there was no difference between initial DVT patients and normal individuals. We demonstrated elevated procoagulant activity of platelet-free plasma in DVT patients relative to normal individuals, and a positive correlation with MPTF.

Conclusions

The elevated MPTF could be a potentially predictor for DVT recurrence. Further studies are needed to validate its sensitivity and specificity.     

Overweight and obesity in patients with bipolar disorder or schizophrenia compared with a non-psychiatric sample

Background

Depression is characterized by activation of cell-mediated immunity (CMI), including increased neopterin levels, and increased pro-inflammatory cytokines (PICs), such as interleukin-1 (IL-1) and tumor necrosis factor-α (TNFα). These PICs may induce depressive, melancholic and chronic fatigue (CF) symptoms.

Methods

We examined serum neopterin and plasma PIC levels in depressive subgroups in relation to the depressive subtypes and the melancholic and CF symptoms of depression. Participants were 85 patients with depression and in 26 normal controls. Severity of depression was assessed with the Hamilton Depression Rating Scale (HDRS) and severity of CF with the Fibromyalgia and Chronic Fatigue Syndrome (FF) Rating Scale.

Results

Serum neopterin was significantly higher in depressed patients and in particular in those with melancholia. There were positive correlations between serum neopterin, the plasma PICs and the number of previous depressive episodes. Neopterin and TNFα were associated with melancholia, while both PICs were associated with CF. Melancholia-group membership was predicted by the HDRS and neopterin, and CF group membership by age, the FF score and serum TNFα.

Discussion

Depression and melancholia are accompanied by CMI activation, suggesting that neopterin plays a role in their pathophysiology, e.g. through activation of oxidative and nitrosative stress and apoptosis pathways. The intertwined CMI and inflammatory responses are potentially associated with the onset of depression and with the melancholic and CF symptoms of depression. Exposure to previous depressive episodes may magnify the size of CMI and PIC responses, possibly increasing the likelihood of new depressive episodes. CMI activation and inflammation may contribute to the staging or recurrence of depression.     

Phénomène d’Uhthoff lié à l’effort, isolé, précédant une sclérose en plaques

Introduction

Described in 1890, Uhthoff's symptom corresponds to a transient blurred vision provoked by physical exercise or an increase of temperature. It is a frequent symptom occurring during the course of multiple sclerosis.

Patients and method

We report here four cases of patients presenting isolated Uhthoff phenomenon preceding multiple sclerosis by several years.

Results

These four patients presented transient neurological symptoms induced by intensive sporting activity for 1 to 6 years before diagnosis of multiple sclerosis. These symptoms were often visual but sometimes motor or sensorial. All symptoms appeared above a certain threshold specific to each patient, after 15 to 30 minutes of intense physical exercise (bike, running or handball) and all disappeared after a few minutes to one hour rest with full recovery to baseline.

Discussion

Uhthoff's phenomenon is explained by a conduction block. It is due to axonal demyelization that provokes a reorganization of sodium channels induced by a decrease in a safety factor highly sensitive to temperature, or by release of soluble blocking substances (oxide nitric or cytokines).

Conclusion

Without being specific, this symptom is strongly suggestive of this disease. Our case reports confirm the existence of “infraclinic multiple sclerosis”.     

The incidence of deep vein thrombosis in women undergoing cesarean delivery

Introduction

Venous thromboembolism (VTE) is one of the leading causes of maternal mortality in the United States. Cesarean delivery is a known risk factor. This study was to determine the incidence of deep vein thrombosis (DVT) post cesarean delivery.

Materials and Methods

This was a prospective cohort study where two patients having undergone cesarean delivery each day were randomly selected. A lower extremity compression ultrasound was performed prior to hospital discharge. If no DVT was detected, participants were asked to return for a second ultrasound two weeks postpartum. Participants were also telephone-interviewed at three months for reported VTE.

Results

Of the 194 patients who consented to study participation, only one participant developed DVT after cesarean delivery, giving an overall incidence of 0.5% (95% CI, 0.1 to 2.8%). There were no DVT identified on the second ultrasound nor VTE reported 3 months postpartum.

Conclusions

We found the DVT rate after cesarean delivery to be 0.5%.     

Time interval between stroke onset and hospital arrival in acute ischemic stroke patients in Shanghai, China

Objective

To observe the time interval between stroke onset and hospital arrival (time-to-hospital) in acute ischemic stroke patients and analyze its putatively associated factors.

Methods

During the period from November 1, 2006 to August 31, 2008, patients with acute ischemic stroke admitted consecutively to the Department of Neurology, Ninth Hospital, Shanghai, were enrolled in the study. Information of the patients was registered including the time-to-hospital, demographic data, history of stroke, season at attack, neurological symptom at onset, etc. Characteristics of the patients were analyzed and logistic regression analyses were conducted to identify factors associated with the time-to-hospital.

Results

There were 536 patients in the study, 290 (54.1%) males and 246 (45.9%) females. The median time-to-hospital was 8 h (ranged from 0.1 to 300 h) for all patients. Within 3 h after the onset of stroke, 162 patients (30.2%) arrived at our hospital; and within 6 h, 278 patients (51.9%). Patients with a history of stroke, unconsciousness at onset, or a high NIHSS score at admission had significantly less time-to-hospital.

Conclusion

The time interval between stroke onset and hospital arrival was <6 h for around half of our patients with acute cerebral ischemic stroke. A history of stroke and severe symptoms at onset were significantly associated with shorter time-to-hospital. The results might indicate that the knowledge of stroke and understanding the importance of seeking immediate medical help after stroke onset of patients and their relatives could significantly influence their actions.     

Family psychiatric history, peritraumatic reactivity, and posttraumatic stress symptoms: A prospective study of police

Background

Family history of psychiatric and substance use disorders has been associated with posttraumatic stress disorder (PTSD) in cross-sectional studies.

Method

Using a prospective design, we examined the relationships of family history of psychiatric and substance use disorders to posttraumatic stress symptoms in 278 healthy police recruits. During academy training, recruits were interviewed on family and personal psychopathology, prior cumulative civilian trauma exposure, and completed self-report questionnaires on nonspecific symptoms of distress and alcohol use. Twelve months after commencement of active duty, participants completed questionnaires on critical incident exposure over the previous year, peritraumatic distress to the worst critical incident during this time, and posttraumatic stress symptoms.

Results

A path model indicated: (1) family loading for mood and anxiety disorders had an indirect effect on posttraumatic stress symptoms at 12 months that was mediated through peritraumatic distress to the officer’s self-identified worst critical incident, (2) family loading for substance use disorders also predicted posttraumatic stress symptoms at 12 months and this relationship was mediated through peritraumatic distress.

Conclusion

These findings support a model in which family histories of psychopathology and substance abuse are pre-existing vulnerability factors for experiencing greater peritraumatic distress to critical incident exposure which, in turn, increases the risk for development of symptoms of posttraumatic stress disorder. Replication in other first responders, military and civilians will be important to determine generalizability of these findings.     

Has the incidence of deep vein thrombosis in patients undergoing total hip/knee arthroplasty changed over time? A systematic review of randomized controlled trials

Background

There is a perception in the orthopaedic and thromboembolism community that the incidence of deep vein thrombosis (DVT) has decreased in patients undergoing total knee arthroplasty (TKA) or total hip arthroplasty (THA).

Objectives

To assess the incidence of DVT with warfarin thromboprophylaxis over time in patients undergoing elective TKA or THA.

Methods

The MEDLINE, EMBASE, and Cochrane Library databases were searched to October 2006, supplemented by a manual search of reference lists. Two reviewers independently extracted data on study characteristics, quality and the frequency of total, symptomatic and proximal DVT.

Results

Fourteen studies (4,423 patients) were included. Total and proximal DVT after TKA declined over time (r = − 0.75, p = 0.031; r = − 0.86, p = 0.007 respectively). Total and proximal DVT after THA did not change. The risk of developing DVT after TKA was significantly higher than after THA (OR 1.85, 95% CI 1.6 - 2.14; p < 0.0001). The risk of developing symptomatic DVT after THA was significantly higher than after TKA (OR 2.18, 95% CI 1.11 - 4.27; p = 0.012).

Conclusions

The incidence of DVT in patients undergoing elective TKA appears to have declined in patients receiving warfarin thromboprophylaxis.     

Accuracy and safety of (99m)Tc-labeled anti-D-dimer (DI-80B3) Fab' fragments (ThromboView®) in the diagnosis of deep vein thrombosis: A phase II study

Background

The assessment of patients with suspected deep vein thrombosis (DVT) remains challenging despite current diagnostic algorithms. ^99mTc-labelled DI-DD3B6/22-80B3 Fab´ fragments (^99mTc-DI-80B3, ThromboView®) is a novel diagnostic test that uses a radiolabelled humanized monoclonal antibody fragment specific for the D-dimer region of cross-linked fibrin to detect DVT. This test has an anatomic component to locate DVT and a functional component to differentiate acute (newly formed) thrombus from inactive (old) thrombus.

Methods

In a multi-centre prospective cohort trial we investigated the diagnostic accuracy and safety of ^99mTc-DI-80B3 in consecutive patients with suspected DVT who had the diagnosis confirmed or excluded by venography.

Results

We enrolled 94 patients with suspected DVT of whom 12 did not have ^99mTc-DI-80B3 imaging, leaving 82 patients for the safety analysis. Of these patients, there were 16 with non-evaluable imaging (11 venography, 7 ^99mTc-DI-80B3, both in two patients) leaving 66 patients for the accuracy analysis. ^99mTc-DI-80B3 imaging was well-tolerated: 2 patients developed urticaria; none developed serious adverse events. For proximal DVT, the sensitivity (84.2%; 95% confidence interval [CI]: 62.4-94.5) and specificity (97.6%; CI: 83.3-99.4) were highest when the combined 0.25-hour and 3-hour ^99mTc-DI-80B3 images were used. The accuracy was lower for distal DVT, irrespective of the images used. There were insufficient patients to comment on the accuracy of ^99mTc-DI-80B3 imaging for suspected recurrent DVT.

Conclusions

^99mTc-DI-80B3 (ThromboView®) is a novel diagnostic modality for patients with suspected DVT with a promising accuracy and safety profile that justifies additional clinical development in diagnostic accuracy and clinical management studies.     

Does a decrease in avoidance behavior and focusing on fatigue mediate the effect of cognitive behavior therapy for chronic fatigue syndrome?

Objective

Cognitive behavior therapy (CBT) leads to a significant reduction in fatigue severity and impairment in patients with chronic fatigue syndrome (CFS). The purpose of the present study was to determine whether the effect of CBT for CFS on fatigue and impairment is mediated by a decrease in avoidance behavior and focusing on fatigue.

Methods

For this purpose, we reanalyzed a randomized controlled trial which was previously conducted to test the efficacy of CBT for CFS. Two hundred nineteen patients completed assessment prior and subsequent to treatment or a control group period.

Results

Mediation analysis revealed that a decrease in focusing on fatigue mediated the effect of CBT for CFS on fatigue and impairment. Avoidance of activity and avoidance of aversive stimuli were not significantly changed by treatment and were therefore excluded from mediation analysis.

Conclusion

A decrease in the focus on fatigue seems to contribute to the treatment effect of CBT for CFS.     

IgG deficiency and expansion of CTG repeats in myotonic dystrophy

Objectives

Expansion of CTG repeats in myotonic dystrophy (DM1) alters the regulated expression of numerous genes. It is considered to explain the major clinical features of DM1. IgG deficiency is common in DM1 and is due to altered FcRn-related hypercatabolism. We hypothesized that the IgG catabolic rate is correlated with CTG repeat expansion.

Methods

Correlations between serum immunoglobulin levels, peripheral lymphocyte subset counts and CTG repeat numbers were performed in 52 DM1 patients.

Results

Serum IgG and IgG1 levels were below the normal limit respectively in 54% and 72% of patients. Increasing CTG repeat numbers were significantly correlated with decreasing serum IgG and IgG1 levels, and with decreasing CD3⁺ T-cell and CD3⁺-CD8⁺ cell counts. An abnormal immunoglobulin profile at protein electrophoresis was found in 4 patients.

Conclusion

We conclude that the catabolic rate of IgG is linked to expanded CTG repeats, possibly involving an altered immune response.     

Outpatient management of acute deep vein thrombosis: results from the OTIS-DVT registry

Objectives

We aimed to investigate clinical practice patterns for the outpatient management of acute deep vein thrombosis (DVT).

Methods

In the prospective Outpatient Treatment of Deep Vein Thrombosis in Switzerland (OTIS-DVT) registry, 534 consecutive outpatients with acute DVT (49% proximal, 24% recurrent, and 12% cancer-associated) were enrolled: 41% patients were managed in private angiology practice, 34% in an outpatient hospital department, and 25% in private general or internal medicine practice.

Results

For diagnosis, ultrasound was used in 95% and D-dimer testing in 53%. Low-molecular-weight heparin (LMWH) was prescribed for a median (IQR) duration of 7 (5-12) days in 83% of patients, and vitamin K-antagonists for 163 (92-183) days in 81%. Mechanical measures to prevent post-thrombotic syndrome were prescribed in 83%; compression stockings or bandages for a median (IQR) duration of 364 (101-730) days from hospital physicians, and 92 (45-183) days from private practice physicians (p < 0.001). Among patients with symptomatic proximal DVT, mechanical measures were prescribed for at least 2 years in 24% patients; 55% in hospital, and 6% in private practice (p < 0.001). Among patients with cancer-associated DVT, the median (IQR) duration of LMWH therapy was 16 (8-45) days, and 35% received LMWH for less than 90 days.

Conclusions

The OTIS-DVT registry provides representative information on clinical practice patterns for outpatients with acute DVT managed by hospital or private practice physicians. The use of mechanical measures in patients with symptomatic proximal DVT and the administration of LMWH for a long-term therapy of cancer-associated DVT require improvement to comply with current guidelines.     

Accuracy and usefulness of a clinical prediction rule and D-dimer testing in excluding deep vein thrombosis in cancer patients

Introduction

Deep vein thrombosis (DVT) can be safely and reliably excluded in patients with a low clinical probability and a negative D-dimer result but the accuracy and utility of such a strategy is less certain in cancer patients. We sough to compare the performance of the Wells pretest probability (PTP) model and D-dimer testing between patients with and without cancer and to examine the utility of the two PTP model classification schemes (low/moderate/high versus unlikely/likely) in excluding DVT in patients with cancer.

Materials and methods

Pooled analysis of databases from three prospective diagnostic studies evaluating consecutive outpatients with suspected DVT.

Results

A total of 2696 patients were evaluated. DVT was diagnosed in 403 (15%) patients overall and in 83 of 200 (41.5%) cancer patients. The PTP distribution and the prevalence of DVT in each PTP category were significantly different between patients with and without cancer, regardless of the classification used (p < 0.01). In patients with cancer, the negative predictive values of a low or unlikely PTP score in combination with a negative D-dimer result were 100% (95% CI 69.8%-100%) and 100% (95% CI 82.8%-96.6%), respectively. However, the specificities ranged from 46.2% (95%CI 27.1%-66.3%) to 57.1% (95%CI 41.1%-71.9%). Further testing was required in 94% of cancer patients using the low/moderate/high PTP classification and in 88% using the unlikely/likely stratification.

Conclusions

As in patients without cancer, the combination of a low or unlikely PTP with a negative D-dimer result can exclude DVT in patients with cancer. However, this strategy has limited utility because very few cancer patients present with this combination.     

Mindfulness-based stress reduction for chronic pain conditions: Variation in treatment outcomes and role of home meditation practice

Objective

This study compared changes in bodily pain, health-related quality of life (HRQoL), and psychological symptoms during an 8-week mindfulness-based stress reduction (MBSR) program among groups of participants with different chronic pain conditions.

Methods

From 1997-2003, a longitudinal investigation of chronic pain patients (n=133) was nested within a larger prospective cohort study of heterogeneous patients participating in MBSR at a university-based Integrative Medicine center. Measures included the Short-Form 36 Health Survey and Symptom Checklist-90-Revised. Paired t tests were used to compare pre-post changes on outcome measures. Differences in treatment effect sizes were compared as a function of chronic pain condition. Correlations were examined between outcome parameters and home meditation practice.

Results

Outcomes differed in significance and magnitude across common chronic pain conditions. Diagnostic subgroups of patients with arthritis, back/neck pain, or two or more comorbid pain conditions demonstrated a significant change in pain intensity and functional limitations due to pain following MBSR. Participants with arthritis showed the largest treatment effects for HRQoL and psychological distress. Patients with chronic headache/migraine experienced the smallest improvement in pain and HRQoL. Patients with fibromyalgia had the smallest improvement in psychological distress. Greater home meditation practice was associated with improvement on several outcome measures, including overall psychological distress, somatization symptoms, and self-rated health, but not pain and other quality of life scales.

Conclusion

MBSR treatment effects on pain, HRQoL and psychological well-being vary as a function of chronic pain condition and compliance with home meditation practice.     

Risk factors for delaying treatment seeking in obsessive-compulsive disorder

Background

Despite the multiple alternatives of treatment, it is well known that patients with obsessive-compulsive disorder (OCD) delay seeking treatment. In this study, the aim was to determine the risk factors for delaying treatment seeking in OCD patients.

Methods

The sample consisted of 132 OCD who completed the Yale-Brown Obsessive-Compulsive Scale, Yale-Brown Obsessive-Compulsive Scale Symptom Checklist, and Beck Depression Inventory.

Results

In univariate analyses with risk evaluation, income level, being single or divorced, having a history of psychiatric treatment, poor insight for the symptoms, and obsessions of hoarding were the variables that were found to be significant. In the regression model, history of psychiatric treatment and duration of OCD were the 2 variables that remained statistically significant.

Conclusion

This was the first study wherein the sample included patients who were recruited from a nonpsychiatric department: the dermatology clinic. Application to dermatology has not been determined as a risk factor for delaying treatment seeking in OCD patients.     

Telepsychiatry and carer education for schizophrenia

Objective

Despite the scientific evidence, most families of people with schizophrenia in Europe never receive a carer education programme. We evaluated whether a carer education course delivered by telepsychiatry was as effective as a carer education course delivered in situ.

Method

We delivered the carer education course for schizophrenia simultaneously to a carers group in rural north west Ireland (remote) via three ISDN lines and live to a carers group in a city (host). We compared knowledge gains using the Knowledge Questionnaire before and after each course.

Results

Fifty-six carers of people with schizophrenia participated in the trial. At baseline, participants at the remote and host centers did not differ in terms of knowledge about schizophrenia. After the course, carers at both centers improved significantly and the knowledge gains between groups were equivalent at 6 weeks.

Conclusion

Telepsychiatry can deliver effective carer education programmes about schizophrenia and may provide one solution to bridging the chasm between scientific evidence and clinical reality.     

Activation of coagulation in amniotic fluid during normal human pregnancy

Introduction

Amniotic fluid (AF) is an important medium for fetal development which exhibits high procoagulant activities; however, the role of these procoagulants during pregnancy has not been elucidated and might be associated with pregnancy complications. The current study aimed to evaluate factor X (FX) activation and its association with tissue factor (TF), tissue factor pathway inhibitor (TFPI) and coagulation activation markers in AF during normal human pregnancy.

Methods

Activation of FX and concentration of TF, free TFPI, D-dimer and prothrombin fragments (F1 + 2) were evaluated in AF samples obtained for chromosome analysis from 91 women with normal pregnancy: 65 samples were taken from patients at 16-20 weeks of gestation, 9 samples were drawn at 21-30 weeks and 17 samples−after 30 weeks of gestation.

Results

Activation of FX in AF significantly increased during normal pregnancy (from 65 ± 41 to 205 ± 80 equivalent RVV ng/mg total protein, P < 0.0001). TF and TFPI levels in AF also rose with gestational age. In contrast, the AF concentration of D-dimer and F1 + 2, markers of coagulation activation significantly decreased when expressed per mg total protein. Levels of free TFPI correlated with TF (r = 0.5, P < 0.001), and were 8-fold higher than those of TF during pregnancy.

Conclusion

High levels of TFPI might be associated with the inhibition of procoagulant activity in amniotic fluid during normal pregnancy, which may account for the rarity of clinical amniotic fluid embolism.     

Evidence of increased platelet reactivity in the first six months after acute ST segment elevation myocardial infarction

Introduction

Platelets play a crucial role in the pathogenesis of acute coronary syndromes. Accordingly, previous studies showed increased platelet reactivity on admission in these patients. In this study we assessed platelet reactivity at short-medium term follow-up in patients with ST-segment elevation acute myocardial infarction (STEMI).

Materials and methods

Fifty-nine patients (58 ± 11 years, 45 men), treated with primary angioplasty, were studied 1 month after STEMI. Thirty-five patients were retested at 6 months. Twenty matched patients with stable coronary artery disease served as controls. Platelet reactivity was assessed by flow cyometry at rest and at peak exercise, with and without adenosine diphosphate (ADP) stimulation, by measuring monocyte-platelet aggregates (MPAs) and glycoprotein IIb/IIIa (CD41) expression in the MPA gate, and CD41 and fibrinogen receptor (PAC-1) expression in the platelet gate.

Results

Compared to controls, basal MPAs and CD41 in the MPA gate were higher in STEMI patients both at 1 month (p = 0.001 and p = 0.002, respectively) and at 6 months (p = 0.03 and p = 0.01, respectively). Basal CD41 and PAC-1 expression was also higher in STEMI patients at the two assessments compared to controls (P < 0.001 for both). Exercise induced a similar increase in platelet reactivity in patients and controls. ADP induced a higher increase in CD41 platelet expression in STEMI patients compared to controls both at 1 and 6 months (P < 0.001).

Conclusion

Platelet reactivity is increased in the first 6 months after STEMI. The persistence of increased platelet reactivity in this time period may play a role in the early recurrence of coronary events after STEMI.     

Evaluation of the procoagulant activity of endogenous phospholipids in the platelet-free plasma of children with sickle cell disease using functional assays

Background

The mechanisms of hypercoagulability in sickle cell disease (SCD) are poorly understood.

Objective

We aimed to explore the procoagulant activity of endogenous phospholipids (ePL) in the platelet-free plasma of SCD children.

Methods

A factor Xa clotting time (XACT), thrombin generation (TG) and a capture-based assay for the detection of procoagulant microparticles (PMP) were used. Forty three SCD children (35 SS, 6 SC and 2 Sβ +) were evaluated at steady-state and compared to 20 controls. Fourteen patients were also evaluated during vaso-occlusive crisis. TG was performed using 10pM tissue factor without addition of exogenous phospholipids. A control condition was also performed using 10pM tissue factor and 4 μM phospholipids. Percentages of the test/control conditions were calculated for the peak height (% peak), endogenous thrombin potential (% ETP) and velocity index (% VI).

Results

XACT times were shorter, PMP levels, peak height and velocity index of thrombin generation were higher in SCD patients than controls. Lag time and ETP were not different between the two groups. % peak, % ETP and % VI were higher in patients than controls. Significant correlations were found between PMP levels and XACT, also between PMP levels and peak height, velocity index, ETP and their respective percentages to the control condition, but not with lag time. Double heterozygous patients showed intermediate values for XACT and TG parameters. No significant difference was observed when comparing patients at steady-state versus vaso-occlusive crisis.

Conclusion

High procoagulant activity of ePL was observed in the platelet-free plasma of SCD children, probably borne by procoagulant microparticles. This may contribute to a high hemostatic potential and predisposition to thrombotic complications in these patients.