Interaction of SLC1A1 gene variants and life stress on pharmacological resistance in obsessive-compulsive disorder

Genetic and environmental factors seem to interact and influence both the onset and the course of obsessive-compulsive disorder (OCD), but the role of glutamate transporter variants (SLC1A1) in pharmacological resistance is not known. We aimed to assess whether genetic variants in SLC1A1 and life stress at onset of the disorder interact and modulate pharmacological resistance in OCD. A single-marker association study of several single-nucleotide polymorphisms in the SLC1A1 genomic region was performed in a sample of 238 OCD patients. For the most strongly associated SNP (rs3087879), one copy of the risk allele increased the probability of higher treatment resistance (odds ratio=2.42; 95% confidence interval=1.39-4.21; P=0.0018), but only in OCD patients without life stress at onset of the disorder. These results suggest a gene-by-environment interaction effect on treatment resistance in OCD and strengthen the existing evidence of the role of the glutamatergic system in the phenomenology of OCD.

Association between the NMDA glutamate receptor GRIN2B gene and obsessive-compulsive disorder

BACKGROUND

Recent data from neuroimaging, genetic and clinical trials and animal models suggest a role for altered glutamatergic neuro transmission in the pathogenesis of obsessive-compulsive disorder (OCD). The aim of this study was to investigate whether variants in the GRIN2B gene, the gene encoding the NR2 subunit of the N-methyl-D-aspartate (NMDA) glutamate receptor, may contribute to genetic susceptibility to OCD or to different OCD subphenotypes.

METHODS

Between 2003 and 2008, we performed a case-control association study in which we genotyped 10 tag single-nucleotide polymorphisms (SNPs) in the 3' untranslated region (3' UTR) of GRIN2B. We performed SNP association and haplotype analysis considering the OCD diagnosis and different OCD subphenotypes: early-onset OCD, comorbid tic disorders and OCD clinical symptom dimensions.

RESULTS

We enrolled 225 patients with OCD and 279 controls recruited from the OCD Clinic at Bellvitge Hospital (Barcelona, Spain). No significant difference in the distribution of alleles or genotypes was detected between patients with OCD and controls. Nonetheless, on analyzing OCD subphenotypes, the rs1805476 SNP in male patients (95% confidence interval [CI] 1.37-4.22, p = 0.002) and a 4-SNP haplotype in the whole sample (rs1805476, rs1805501, rs1805502 and rs1805477; odds ratio 1.92, 95% CI 1.22-3.01; permutation p = 0.023) were significantly associated with the presence of contamination obsessions and cleaning compulsions.

LIMITATIONS

Study limitations included the risk of population stratification associated with the case-control design, use of psychiatrically unscreened blood donors as the control group, reduced sample size of participants with certain OCD subphenotypes and tested polymorphisms limited to 3' UTR and exon 13 of GRIN2B.

CONCLUSION

Our results converge with recent data suggesting a possible contribution of glutamatergic variants to the genetic vulnerability to OCD or at least to certain OCD manifestations. The dissection of OCD into more homogeneous subphenotypes may constitute a useful tool to disentangle the complex genetic basis of the disorder.

Variation in the BDNF Val66Met polymorphism and response to cognitive-behavior therapy in obsessive-compulsive disorder

BACKGROUND

Recent research suggests that the brain-derived neurotrophic factor (BDNF) may play a role in extinction learning. The goal of this study was to test whether variation in the BDNF Val66Met polymorphism is related to treatment response to exposure-based cognitive-behavior therapy (CBT), a form of extinction learning, in obsessive-compulsive disorder (OCD).

METHODS

One hundred and six OCD patients from a specialized clinic, who underwent a standardized CBT treatment after partial or non-response to a 12-week pharmacological trial, were genotyped for the BDNF Val66Met and the relationship between genotype and treatment response was analyzed.

RESULTS

Among 98 CBT completers, 36% of those carrying the BDNF Met allele were rated as CBT responders compared to 60% of nonMet allele carriers (P=0.027). When analyzing the different obsessive-compulsive symptom dimensions, in patients with contamination/cleaning symptoms, the Met allele was associated with a significantly worse CBT response (P<0.0001) and a lower obsessions severity decrease from pre- to posttreatment (P=0.046).

CONCLUSION

Genetic variation in BDNF may be associated with treatment response in exposure-based CBT in OCD, especially in those patients exhibiting contamination/cleaning symptoms.

Breakdown in the brain network subserving moral judgment in criminal psychopathy

Neuroimaging research has demonstrated the involvement of a well-defined brain network in the mediation of moral judgment in normal population, and has suggested the inappropriate network use in criminal psychopathy. We used functional magnetic resonance imaging (fMRI) to prove that alterations in the brain network subserving moral judgment in criminal psychopaths are not limited to the inadequate network use during moral judgment, but that a primary network breakdown would exist with dysfunctional alterations outside moral dilemma situations. A total of 22 criminal psychopathic men and 22 control subjects were assessed and fMRI maps were generated to identify (i) brain response to moral dilemmas, (ii) task-induced deactivation of the network during a conventional cognitive task and (iii) the strength of functional connectivity within the network during resting-state. The obtained functional brain maps indeed confirmed that the network subserving moral judgment is underactive in psychopathic individuals during moral dilemma situations, but the data also provided evidence of a baseline network alteration outside moral contexts with a functional disconnection between emotional and cognitive elements that jointly construct moral judgment. The finding may have significant social implications if considering psychopathic behavior to be a result of a primary breakdown in basic brain systems.

Olfactory identification and discrimination in obsessive-compulsive disorder

BACKGROUND

Neuroimaging and neuropsychological data from patients with an obsessive-compulsive disorder (OCD) indicate the dysfunction of the orbitofrontal cortex (OFC). Olfactory processing has been associated with OFC function, although results from OCD studies regarding this sensory modality have been inconclusive. No previous study has analyzed both odor discrimination and identification capacity in OCD patients using "Sniffin' Sticks" tests. The aim of our study was to assess odor threshold, identification, discrimination, and nonverbal memory in OCD patients, in order to determine whether these functions were affected.

METHODS

Olfactory function was measured in 29 OCD patients and 29 healthy volunteers (HV) using the "Sniffin' Sticks" test and their nonverbal memory was scored with the Rey-Osterrieth Complex Figure Test.

RESULTS

OCD patients showed significant impairment in their odor performance and in their execution of the nonverbal memory task compared to HV. No statistical associations were found between the deficits in the two areas. The severity of depressive and obsessive-compulsive symptoms did correlate with olfactory identification.

CONCLUSION

Our findings support the hypothesis that olfactory and memory dysfunctions in OCD reflect different neurobiological alterations of the disorder, and point to the modulation effect of depressive and obsessive-compulsive symptoms on odor performance.

Enhanced brain responsiveness during active emotional face processing in obsessive compulsive disorder

OBJECTIVES. The abnormal processing of emotional stimuli is common to a variety of psychiatric disorders. Specifically, patients with prominent anxiety symptoms generally overreact to emotional cues, which has been linked to increased amygdala activation. However, in OCD, enhanced responses are predominantly obtained using disease-specific stimuli and preferentially involve frontostriatal systems. METHODS. We assessed 21 OCD patients and 21 healthy controls with fMRI during an emotional face-processing paradigm involving active response generation to test for alterations in both brain activation and task-induced functional connectivity of the frontal cortex, the amygdala and the fusiform face area. RESULTS. OCD patients showed significantly greater activation of "face-processing" regions including the amygdala, fusiform gyrus and dorsolateral prefrontal cortex. The reciprocal connectivity between face-processing regions was enhanced in OCD. Importantly, we detected significant correlations between patients' clinical symptom severity and both task-related region activation and network functional connectivity. CONCLUSIONS. The results suggest that OCD patients may show enhanced brain responsiveness during emotional face-processing when tasks involve active response generation. Our findings diverge from previously described alterations in anxiety disorders, as patients showed enhanced amygdala-prefrontal connectivity as opposed to negative reciprocal interaction. This pattern would appear to be disorder-specific and was significantly related to obsessive-compulsive symptom severity.

Stressful life events at onset of obsessive-compulsive disorder are associated with a distinct clinical pattern

BACKGROUND

Environmental stressors are considered to play an important role in the triggering of mental disorders such as obsessive-compulsive disorder (OCD). Although there is extensive literature on traumatic life events, little is known about the role of nontraumatic but nonetheless stressful life events (SLEs) in OCD. The aim of this study was to establish whether OCD preceded by an SLE presents a different clinical pattern compared to non-SLE-preceded OCD.

METHODS

We interviewed 412 OCD patients to assess both SLEs at onset of OCD and other clinical variables, including OCD symptom dimensions. Logistic regression was then applied to explore the relationship between clinical variables and OCD preceded by an SLE.

RESULTS

The SLE-preceded OCD group showed a later onset of the disorder (OR = 1.04, P = .015), a history of complicated birth (OR = 5.54, P<.001), less family history of OCD (OR = 0.42, P = .014), and the presence of contamination/cleaning symptoms (OR = 1.99, P = .01).

CONCLUSIONS

Patients with OCD onset close to an SLE and those without an SLE close to OCD onset show a distinct clinical pattern.

Variants in estrogen receptor alpha gene are associated with phenotypical expression of obsessive-compulsive disorder

Compelling data from animal and clinical studies suggest that sex steroids may play a role in the etiopathology of obsessive-compulsive disorder (OCD). The aim of this study was to investigate whether variants in estrogen receptor genes ESR1 and ESR2 may contribute to the genetic susceptibility to OCD, through a case-control association study using an extensive linkage disequilibrium-mapping approach. Twenty tag single-nucleotide polymorphisms (tagSNPs) covering the ESR2 region and nine tagSNPS from regions of ESR1 reported to be related to transcriptional control were genotyped in 229 OCD patients and 279 controls. SNP association and haplotype analysis were performed. The association of these genes and OCD subphenotypes was tested, considering early-onset OCD, comorbid tic and affective disorders, and OCD symptom dimensions. No significant difference in the distribution of alleles or genotypes was detected between controls and OCD subjects. Nevertheless, on analyzing OCD subphenotypes, SNP rs34535804 in ESR1 and a five SNPs haplotype, located at the 5' end of intron 1 of ESR1, were associated with the presence of contamination obsessions and cleaning compulsions. Specifically, carriers of the ACCCG haplotype, a combination of functional alleles related to higher ER alpha expression, showed a reduced risk of suffering from these symptoms. Our results suggest that the ESR1 gene may contribute to the genetic vulnerability to certain OCD manifestations. The dissection of OCD into more homogeneous subphenotypes may well help to identify susceptibility genes for the disorder.

Memory and strategic processing in first-degree relatives of obsessive compulsive patients

BACKGROUND

The same executive dysfunctions and alterations in neuroimaging tests (both functional and structural) have been found in obsessive-compulsive patients and their first-degree relatives. These neurobiological findings are considered to be intermediate markers of the disease. The aim of our study was to assess verbal and non-verbal memory in unaffected first-degree relatives, in order to determine whether these neuropsychological functions constitute a new cognitive marker for obsessive-compulsive disorder (OCD).

METHOD

Recall and use of organizational strategies in verbal and non-verbal memory tasks were measured in 25 obsessive-compulsive patients, 25 unaffected first-degree relatives and 25 healthy volunteers.

RESULTS

First-degree relatives and healthy volunteers did not show differences on most measures of verbal memory. However, during the recall and processing of non-verbal information, deficits were found in first-degree relatives and patients compared with healthy volunteers.

CONCLUSIONS

The presence of the same deficits in the execution of non-verbal memory tasks in OCD patients and unaffected first-degree relatives suggests the influence of certain genetic and/or familial factors on this cognitive function in OCD and supports the hypothesis that deficits in non-verbal memory tasks could be considered as cognitive markers of the disorder.

Spanish adaptation of the Dimensional Yale-Brown Obsessive-Compulsive Scale

BACKGROUND

The Dimensional Yale-Brown Obsessive-Compulsive Scale (DY-BOCS) is a promising new instrument that allows patient and clinician ratings of dimension-specific symptom severity, as well as estimates of global symptom severity in patients with obsessive-compulsive disorder (OCD). The goal of this study was to further explore the psychometric properties of the DY-BOCS in a Spanish sample.

METHODS

The internal consistency, reliability, and convergent and divergent validity of the Spanish adaptation of the DY-BOCS were assessed in a sample of 51 Spanish adult patients with OCD.

RESULTS

All the subscales of the Spanish DY-BOCS showed high internal consistency. The interrater reliability was excellent for all component scores, and the level of agreement between self-report and expert ratings was high for most symptom dimensions. The subscales of the DY-BOCS were largely independent from one another and from global OCD severity. The convergent and divergent validities of the DY-BOCS subscales were adequate.

CONCLUSIONS

The Spanish version of the DY-BOCS is a reliable and valid clinical tool for the assessment of obsessive-compulsive symptom dimensions.

A case-control study of sex differences in strategic processing and episodic memory in obsessive-compulsive disorder

Although clinical and genetic data for obsessive-compulsive disorder (OCD) support the hypothesis of sexual dimorphism, the neuropsychological findings remain inconclusive. The aim of our study was to determine whether there are differences in cognitive performance between men and women with OCD as compared with healthy controls (HCs). A neuropsychological battery was administered to 50 patients with OCD (31 men and 19 women) and 50 HCs matched by sex, age, and educational level with patients. We evaluated intelligence, attention, episodic memory, and use of organizational strategies during encoding of verbal and nonverbal information. Male patients scored worse than controls did in measures of nonverbal memory tasks, whereas the cognitive performance of women with OCD was consistent with that of their HC counterparts. These results suggest a distinct pattern of cognitive dysfunction specific to the patients' sex.

Comorbidity in pathological gambling: clinical variables, personality and treatment response

INTRODUCTION

Pathological gambling shows high comorbidity rates, especially with substance use disorders, although affective, anxiety and other impulse control disorders, as well as personality disorders, are also frequently associated.

OBJECTIVES

To explore comorbidity in pathological gambling with other mental disorders in a consecutive sample of patients attending a unit specialized in pathological gambling, and specifically the relationship between substance-related disorders, on the one hand, and personality and clinical variables in pathological gamblers, on the other.

METHOD

A total of 498 patients with a DSM-IV-TR diagnosis of Pathological Gambling (11.8% women) were assessed with a semi-structured clinical interview and several clinical and personality scales.

RESULTS

Higher comorbidity with affective disorders was found in women (30.5%), while higher comorbidity with substance-related disorders was found in men (11.2%). A positive association was also detected between a history of psychiatric disorders and current comorbidity with substance-use disorders, as well as between alcohol abuse and age. Finally, some personality traits such as low reward dependence (OR=0.964) and high impulsivity (OR=1.02) predicted other substance abuse (not alcohol). High selftranscendence scores predicted both alcohol and other substance abuse (OR=1.06).

CONCLUSIONS

Our results suggest a high prevalence of comorbid disorders in pathologic gambling, mainly with affective and substance-related disorders. The results of the present study, conducted in a broad sample of consecutively admitted pathologic gamblers, may contribute to understanding of this complex disorder and treatment improvement.

Genetic susceptibility to obsessive-compulsive hoarding: the contribution of neurotrophic tyrosine kinase receptor type 3 gene

Recent work suggests that neurotrophic factors may contribute to the genetic susceptibility to obsessive-compulsive disorder (OCD). Among other clinical dimensions, the presence of hoarding obsessions and compulsions has been shown to be correlated with a number of clinical and neuroimaging findings, as well as with a different pattern of genetic inheritance. We used a linkage disequilibrium (LD)-mapping approach to investigate whether neurotrophic tyrosine kinase receptor type 3 (NTRK3), the high-affinity receptor of neurotrophin 3 (NT-3), plays a role in increasing susceptibility to hoarding in OCD. We performed an association study of 52 tag single nucleotide polymorphisms (tagSNPs) covering the whole NTRK3 gene in a sample comprising 120 OCD patients and 342 controls. Single nucleotide polymorphism association and haplotype analysis were performed. Thirty-six of our patients (30%) exhibited significant hoarding obsessions and compulsions. A significant association of two SNPs in the 3' downstream region of NTRK3 gene and obsessive-compulsive hoarding was identified: rs1017412 [odds ratio (OR) = 2.16; P = 0.001] and rs7176429 (OR = 2.78; P = 0.0001), although only the latter remained significant after Bonferroni correction. Although the haplotype analysis did not show significant results, a more extended block of LD in the OCD hoarders with respect to the control group was observed, suggesting a lower haplotype diversity in these individuals. Our findings suggest that NTRK3 may contribute to the genetic susceptibility to hoarding in OCD and may constitute an interesting gene to focus on in studies of the genetic basis of obsessive-compulsive hoarding.

Clinical implications of insight assessment in obsessive-compulsive disorder

Poor insight has been reported in 15% to 36% of patients with obsessive-compulsive disorder (OCD), but little is known about its clinical correlations. This study examines insight among patients with OCD using a standardized instrument, the Brown Assessment of Beliefs Scale, and analyzes its relationship with clinical factors. Insight was assessed in 132 patients with OCD, before and after pharmacologic treatment, using the Brown Assessment of Beliefs Scale. Differences between patients with good and poor insight on sociodemographic variables, OCD severity, comorbidity, and treatment response were studied. Stability of insight after pharmacologic treatment was also examined. Thirty-nine patients (29.5%) exhibited poor insight. They showed more depressive symptoms (P = .001) and personality disorders (P = .001), especially the schizotypal form, than did good insight subjects, but there were no significant differences in treatment response. Insight significantly improves after treatment (P < .001). Our results suggest that insight in OCD varies widely and constitutes a dynamic phenomenon that can improve after treatment and is influenced by clinical conditions such as affective status or personality.

Extensive genotyping of the BDNF and NTRK2 genes define protective haplotypes against obsessive-compulsive disorder

BACKGROUND

Family, twin and molecular studies provide increasing evidence for the importance of genetic factors in obsessive-compulsive disorder (OCD). Recent work suggests that brain-derived neurotrophic factor (BDNF) may be involved in OCD pathophysiology. We used a linkage disequilibrium (LD)-mapping approach to investigate the role that BDNF and its specific receptor neurotrophic tyrosine kinase receptor type 2 (NTRK2) may play in increasing susceptibility to OCD.

METHODS

Eight tag single nucleotide polymorphisms (tagSNPs) covering the BDNF gene region and 46 tagSNPs in the NTRK2 region were genotyped in 215 OCD patients and 342 control subjects. Single nucleotide polymorphism association and haplotype analysis were performed. The possible relationship between genetic factors and clinical characteristics including age of OCD onset, tic disorders, clinical dimensions, and family history of OCD were investigated.

RESULTS

Haplotype analysis revealed a significant association between OCD and a five-marker protective haplotype located toward the 5' of the BDNF gene (odds ratio [OR] = .80; 95% confidence interval [CI] = .69-.92; permutation p value = .006) containing the functional valine (Val)66-to-methionine (Met) variant. A significant association between a NTRK2 intronic SNP (rs2378672) and OCD was identified (p < .0001) in female patients under an additive model. A protective haplotype located in intron 19 of NTRK2 was also associated with OCD (OR = .76; 95% CI = .66-.87; permutation p value = .001).

CONCLUSIONS

These findings support a role for the BDNF/NTRK2 signaling pathway in genetic susceptibility to OCD.

[Ca-dependent modulation of human glycine receptors expressed in cultured cell lines]

Glycine receptors (GlyRs) provide the main inhibitory neurotransmission in spinal cord and brainstem synapses of vertebrates. Fucile et al. (2000) discovered that elevation of intracellular Ca2+ caused rapid potentiation of GlyRs. This modulation develops in less than 100 ms. It is characterized by an increase in GlyR apparent affinity for glycine. It has been suggested that the phenomenon of Ca-induced potentiation involves an unknown Ca2+-binding protein (CaBP). Using the yeast two-hybrid system, screening of human brain cDNA library against the cytoplasmic loop of human alpha 1 subunit (GlyRhl) allowed us to identify five new interactors. One of them belongs to a family of Ca-binding proteins. We analyzed effect of "short" forms of this protein (CaBP-S) on functional properties of GlyRhl expressed in HEK-293 and CHO cells. Using whole-cell recordings and rapid agonist application we constructed concentration dependencies of glycine-induced currents. This analysis revealed statistical differences in EC50s between control cells (expressing only GlyRhl) and those expressing CaBP-S. In HEK-293 cells recorded under conditions of low intracellular Ca concentration (BAPTA 20 mM in the recording pipette), EC50 for glycine in control cells and expressing GlyRhl + CaBP-S were, correspondently, 68+/-49 microM (n = 29) and 409 +/-421 microM (n = 60). In CHO cells EC50 were 54+/-43 microM (n = 25) and 123 +/-104 microM (n = 28). These differences were statistically not significant at recording with intracellular solution containing high Ca concentration (50 microM). In this case EC50 were correspondently 35+/-28 microM (n = 7) and 64 +/-38 microM (n = 7). These results suggest that CaBP-S causes decrease of GlyR sensitivity to agonist through interaction with cytoplasmic domain of GlyR.

Functional interaction map of lyssavirus phosphoprotein: identification of the minimal transcription domains

Lyssaviruses, the causative agents of rabies encephalitis, are distributed in seven genotypes. The phylogenetically distant rabies virus (PV strain, genotype 1) and Mokola virus (genotype 3) were used to develop a strategy to identify functional homologous interactive domains from two proteins (P and N) which participate in the viral ribonucleoprotein (RNP) transcription-replication complex. This strategy combined two-hybrid and green fluorescent protein-reverse two-hybrid assays in Saccharomyces cerevisiae to analyze protein-protein interactions and a reverse genetic assay in mammalian cells to study the transcriptional activity of the reconstituted RNP complex. Lyssavirus P proteins contain two N-binding domains (N-BDs), a strong one encompassing amino acid (aa) 176 to the C terminus and a weak one in the 189 N-terminal aa. The N-terminal portion of P (aa 52 to 189) also contains a homomultimerization site. Here we demonstrate that N-P interactions, although weaker, are maintained between proteins of the different genotypes. A minimal transcriptional module of the P protein was obtained by fusing the first 60 N-terminal aa containing the L protein binding site to the C-terminal strong N-BD. Random mutation of the strong N-BD on P protein identified three highly conserved K residues crucial for N-P interaction. Their mutagenesis in full-length P induced a transcriptionally defective RNP. The analysis of homologous interactive domains presented here and previously reported dissections of the P protein allowed us to propose a model of the functional interaction network of the lyssavirus P protein. This model underscores the central role of P at the interface between L protein and N-RNA template.

Hyperosmotic stress response and regulation of cell wall integrity in Saccharomyces cerevisiae share common functional aspects

The osmosensitive phenotype of the hog1 strain is suppressed at elevated temperature. Here, we show that the same holds true for the other commonly used HOG pathway mutant strains pbs2 and sho1ssk2ssk22, but not for ste11ssk2ssk22. Instead, the ste11ssk2ssk2 strain displayed a hyperosmosensitive phenotype at 37 degrees C. This phenotype is suppressed by overexpression of LRE1, HLR1 and WSC3, all genes known to influence cell wall composition. The suppression of the temperature-induced hyperosmosensitivity by these genes prompted us to investigate the role of STE11 and other HOG pathway components in cellular integrity and, indeed, we were able show that HOG pathway mutants display sensitivity to cell wall-degrading enzymes. LRE1 and HLR1 were also shown to suppress the cell wall phenotypes associated with the HOG pathway mutants. In addition, the isolated multicopy suppressor genes suppress temperature-induced cell lysis phenotypes of PKC pathway mutants that could be an indication for shared targets of the PKC pathway and high-osmolarity response routes.

Home treatment of deep venous thrombosis with low molecular weight heparin: Long-term incidence of recurrent venous thromboembolism

Outpatient treatment of deep venous thrombosis (DVT) with low molecular weight heparin (LMWH) seems as safe and effective as inpatient treatment with unfractionated heparin (UFH). However, most of the randomized trials comparing a LMWH with UFH described clinical outcomes within 3-6 months. The long-term incidence of recurrent VTE after treatment of DVT with LMWH remains to be established. The primary objective of this retrospective study was to document the long-term incidence of recurrent venous thromboembolism (VTE) in patients with DVT treated with a LMWH, nadroparin in an outpatient basis. The patients were evaluated 46 months after inclusion in two cohorts comparing home treatment with nadroparin (n = 130) with in-hospital treatment with intravenous UFH (n = 149). More than 60% of the patients in the nadroparin group could be treated at home, either entirely or after a short stay in hospital. The age-adjusted thrombosis-free survival was not statistically significant between nadroparin and UFH-treated patients (P = 0.084). There was a nonsignificant trend favoring nadroparin as compared with UFH. The hazard ratio (HR) for recurrent VTE in the nadroparin group with respect to the UFH group was 0.44 (95% confidence interval, 0.17-1.12). No significant differences were observed in overall mortality or major hemorrhage between the two treatment groups. Our study suggests that home treatment of DVT with LMWH is at least as effective and safe as in-hospital UFH after a long-term follow-up period.

Recurrent venous thromboembolism in a Spanish population: incidence, risk factors, and management in a hospital setting

The major concern in the management of venous thromboembolism is the propagation of thrombus and rethrombosis. The incidence of recurrences and the duration of oral anticoagulant therapy in these patients are still controversial. The aim of this study was to determine the incidence, timing, and outcome of further thrombotic events after an initial episode of venous thromboembolism in a hospital setting. In addition, we evaluated potential risk factors for all these outcomes. This was designed as a retrospective analysis of all patients admitted to our Center with an episode of deep vein thrombosis and/or pulmonary embolism between 1986 and 1996. The patients included in the study had to be treated with unfractionated heparin or low molecular weight heparin, followed by at least 3 months of oral anticoagulants. Natural and acquired hemostasis inhibitors were assayed in patients aged less than 50 years. A total of 290 patients with a first episode of venous thromboembolism were included in the study. A total of 33 patients (11.9%, 95% confidence interval. 7.4-14.6) had recurrent episodes. The cumulative incidence of recurrent venous thromboembolism after 2, 5, and 10 years was 7.68, 10, and 12.4%, respectively. The incidence of rethrombosis was significantly higher in patients with idiopathic venous thromboembolism than in patients with secondary thrombosis. Abnormalities of hemostasis were found in 54.5% (95% confidence interval, 37.6-71.4) of the patients with recurrences and under the age of 50 years. Three of seven patients who stopped anticoagulant therapy after the second episode presented a third thrombotic event. In our study population, those patients with idiopathic venous thromboembolism seem to have an increased risk of recurrence. The second thrombotic episode occurs more frequently during the following 2 years after cessation of anticoagulation therapy. Our findings strongly support the use of long-term anticoagulant therapy in patients with recurrent venous thromboembolism.

Population pharmacokinetic approach to compare oral and i.v. administration of etoposide

The antitumor effect of etoposide (ETO) may be related to duration of exposure to a relatively low serum level while myelosuppression may be dependent on peak ETO serum levels. With regard to such therapeutic ranges, duration of exposure to predefined plasma ETO concentration ranges and the related AUC (expressed as percent of total AUC, pAUC) were used to compare pharmacokinetic profiles after oral and short time i.v. (1 h infusion) administration of identical ETO doses (100 mg/m2). Patients included in this study received i.v. (18 patients, short-term infusions) or oral (16 patients) ETO on different treatment schedules. Plasma ETO concentrations were determined by HPLC and population pharmacokinetic parameters were calculated (P-Pharm 1.4). Despite an 'apparent bioavailability' of 59%, oral administration of ETO was associated with the same time of exposure to a predefined 'therapeutic range' of 0.5-3 mg/l and a significantly higher pAUC compared to i.v. administration. By contrast, time of exposure to the probably more myelotoxic concentration range above 3 mg/l was significantly shorter and the related pAUC was highly significantly lower after oral than after i.v. administration. These findings demonstrate that oral ETO therapy is at least equivalent to short time i.v. therapy in terms of achieving specific target concentration ranges and avoiding peak concentrations.

Monitoring oral anticoagulant treatment from plasma stored for up to 48 hours and frozen plasma

BACKGROUND AND OBJECTIVE

The number of patients being referred for lifelong anticoagulant treatment has increased markedly in the last years. The prothrombin time test is sometimes difficult to perform the same day as sample collection. The aim of this study is to determine International Normalized Ratio (INR) and vitamin-K dependent factor levels of frozen plasma and plasma stored for up 48 hours.

DESIGN AND METHODS

The INR of 84 patients receiving acenocoumarol were determined fresh (0 hours), on samples stored between 2 degrees C and 8 degrees C for 24 hours and 48 hours, and on frozen samples (-40 degrees C) using 4 different thromboplastin reagents (Thromboplastin IS; Thromborel; Simplastin; and Thromboplastin D+G). In addition, factors II, VII, IX, X were determined in 34 of these patients in all these situations. We used the interclass correlation coefficient to compare the results obtained at 0 hours and the results obtained in the subsequent measurements. Both measurement and proportional errors were also estimated by linear regression analysis.

RESULTS

The correlation coefficient of the INR between fresh and frozen plasma was 0.98, 0.98, 0.92 and 0.97 for IS, Thromborel, Simplastin and D+G respectively. The correlation between 0 and 24 hours was 0. 98, 0.91, 0.95 and 0.85 for IS, Thromborel, Simplastin and D+G respectively. By 48 hours although IS still had r=0.94, Thromborel, Simplastin, and D+G had r=0.55, r=0.50 and r=0.81, respectively. By 24 hours in stored plasma and in frozen plasma the activity of vitamin-K dependent factors was slightly reduced (r=0.97 at 24h/r=0. 94 with frozen plasma for factor II, r=0.92/0.96 for factor VII, r=0. 83/0.98 for factor IX, and r=0.98/0.95 for factor X). By 48 hours however, significant reductions were noted in the activity of these factors (r=0.94 for factor II, r=0.88 for factor VII, r=0.70 for factor IX, and r=0.98 for factor X).

INTERPRETATION AND CONCLUSIONS

The INR can be reliable determined in frozen plasma and in plasma stored at 2-8 degrees C for up to 24 hours.

Elective splenectomy in relapsing thrombotic thrombocytopenic purpura

Between 20 and 40% of surviving patients with thrombotic thrombocytopenic purpura (TTP) have relapses. Plasma exchange therapy is usually effective in treating relapses, but this treatment does not prevent TTP recurrence. The role of splenectomy in relapsing TTP is still controversial. We describe a patient with multiple relapses of TTP who was successfully treated with elective splenectomy.

Home treatment of deep vein thrombosis: a two-years experience of a single institution

BACKGROUND AND OBJECTIVE

Low molecular weight heparin (LMWH) is known to be safe and effective for the initial treatment of patients with acute deep-vein thrombosis (DVT). Moreover, LMWH allows patients to be treated at home. However, only limited data are available on the feasibility of LMWH treatment at home in daily clinical practice.

DESIGN AND METHODS

We evaluated the feasibility, efficacy and safety of home treatment of DVT in a consecutive series of outpatients using LMWH over a two year period. The two main reasons for exclusion were concomitant pulmonary embolism and a high hemorrhagic risk. Patients were treated with 95 IU/kg bid of nadroparin for a minimum of 7 days. The study design allowed patients to go home immediately after diagnosis or to be discharged after a short hospital stay. Anticoagulation with acenocoumarol was started 2 days before discontinuing nadroparin.

RESULTS

From 1995 to 1997, 71 consecutive outpatients with DVT were treated with nadroparin. Ambulatory treatment was feasible in 39 patients (24 patients did not require admission and 15 patients were discharged in less than 48 hours). The remaining 32 patients were treated in hospital. The main causes for admission were the presence of serious comorbid conditions, the severity of symptoms in the involved leg and the inability to obtain a diagnosis. None of the patients had clinical recurrent venous thromboembolism during the initial treatment with nadroparin. One patient receiving nadroparin at home had a non-fatal major bleeding. None of the patients to whom the possibility of home therapy was offered wished to remain at hospital. However, only 26% of the home-treated patients injected the drug by themselves.

INTERPRETATION AND CONCLUSIONS

Home therapy of DVT with LMWH bid at doses adjusted to patient's body weight is feasible, efficient and safe. Over 50% of outpatients with DVT can be treated at home, either entirely or after a short stay in hospital. Nevertheless, before using this therapeutic alternative as a standard of practice, an adequate assessment of embolic and hemorrhagic risks, and comorbid conditions, should be made.

[Cutaneous B-cell lymphoma with aggressive clinical presentation: apropos of a case]

A patient with an atypical clinical presentation of cutaneous B-cell lymphoma is reported. He showed a rapidly growing tumour with areas of skin necrosis, haemorrhage, ulceration and suppuration in his upper back. There were involvement of contiguous anatomic site and extracutaneous spread. The histology showed diffuse lymphoid infiltration of the dermis. The cell morphology was that of a monotonous population of centroblasts. Treatment with CHOP and radiotherapy provided long-term complete remission. This case illustrates that primary cutaneous B-cell lymphoma may behave as a high-grade malignancy. Vigorous treatment with chemotherapy and radiotherapy is recommended in such cases.

[Skin lesions in epidemic Kaposi's sarcoma (AIDS): local control assessment and esthetic results of a schedule of superficial radiotherapy]

This prospective study was undertaken to evaluate the clinical response of 51 cutaneous lesions of epidemic Kaposi sarcoma in patients with AIDS (EKS/AIDS), obtained with the use of a scheme of superficial radiotherapy (3 Gy/fraction, three fractions weekly up to a total dose of 30 Gy). The mean follow-up time was 9.3 months and the mean time to progression of EKS/AIDS disease was 7-8 months. The initial clinical parameters (pain, size, edema, and esthetics) of each cutaneous lesion were compared with those obtained after one week, one month and three months of therapy. An objective pain improvement was observed in 72% of early lesions and with statistic significance (after one week p = 0.003). After one month of therapy a decrease in lesion size, edema, and esthetic improvement was observed in 78%, 71% and 77%, respectively. Although the evolution and prognosis of EKS/AIDS remains unchanged, it indeed provided palliation, with improvement of local control and esthetics, which together with the simplicity of its application and absence of untoward effects render this radiotherapy technique a very useful indication.

[Pharmacokinetics of etoposide short-term infusions within the scope of the GPOH therapy protocol]

Important interpatient variability of etoposide pharmacokinetics during continuous infusion has been reported and drug level targeting, therefore, been suggested. The current German therapeutic protocols are mainly based on short-term infusion. We determined pharmacokinetic parameters during short-term infusion in 18 children aged between 10/12 and 17 years on different therapeutic schedules in order to investigate interpatient variability. The dosages ranged from 66 to 200 mg/m2. In the subgroup of patients who received 150 mg/m2 (n = 10) the AUC was 106 +/- 15 micrograms.h/ml (range 82-139), clearance 24 +/- 3 ml/min/m2 (18-31), t1/2 3.5 +/- 0.4. To compare kinetic data of all 21 courses in 18 children, standard AUC was calculated (AUC/100 mg/m2). The AUC then was (68 +/- 17 micrograms.h/ml)/(100 mg/m2). Half-life was 3.3 +/- 0.7 h and total clearance 26 +/- 6 ml/min/m2, respectively. In 5 courses in children < 2 years (< 10 kg), pharmacokinetic parameters were within the normal range. In this group dosage was calculated per kg. Dose reduction of 31% (mean) resulted in 22% (mean) lower AUC's. In conclusion, interpatient variability of etoposide pharmacokinetics during short-term infusion is limited. Dose reduction in children < 2 years is not substantiated by our pharmacokinetic data.

Investigation of the variability of etoposide pharmacokinetics in children

PROBLEM

The interindividual variation of etoposide pharmacokinetics under different therapeutic schedules and the rationale of dose reduction in young children and newborns were investigated in the present study.

PATIENTS AND METHODS

We evaluated pharmacokinetic parameters during short-term infusion in 21 therapy cycles (18 children) on different therapeutic schedules (66-200 mg/m2). In 33 patients state levels (Css) during continuous infusion of 125 mg/m2/96 h were analyzed by an HPLC-method.

RESULTS

During short-term infusion half-life (3.3 +/- 0.7 h) and total body clearance (26 +/- 6 ml/min/m2) showed a relatively narrow range. Calculation of the area under the curve was standardized to a dosage of 100 mg/m2 (AUC/[100 mg/m2]). The AUC then was 68 +/- 17 (micrograms.h/ml)/(100 mg/m2) with a coefficient of variation of 25%. In the subgroup of 10 patients who received 150 mg/m2 the AUC was 106 +/- 15 micrograms.h/ml with only 14% coefficient of variation. In children < 2 years, pharmacokinetic parameters were within the normal range. Calculation of the doses the short-term infusion per kg resulted in a dose reduction or 31% (mean, n = 5) and in 22% (mean) lower AUC's. With continuous infusion of 125 mg/m2 etoposide the interpatient variability was greater with a 33% coefficient of variation of the Css (4.4 +/- 1.4 micrograms/ml; n = 24). Calculation of the doses per kg (age < 1 year) or 2/3.kg resulted in reduced Css. Standardization of these levels showed Css (125 mg/m2) of 4.6 +/- 1.4 micrograms/ml and a coefficient of variation of 31%.

CONCLUSIONS

Interpatient variability of etoposide pharmacokinetics at least during short-term infusion is limited. Dose reduction is not substantiated in children < 2 years by our pharmacokinetic data.