Mismatch negativity and low frequency oscillations in schizophrenia families

Objective

Theta-alpha range oscillations have been associated with MMN in healthy controls. Our previous studies showed that theta-alpha activities are highly heritable in schizophrenia patients’ families. We aimed to test the hypothesis that theta-alpha activities may contribute to MMN in schizophrenia patients and their family members.

Methods

We compared MMN and single trial oscillations during MMN in 95 patients, 75 first-degree relatives, 87 controls, and 34 community subjects with schizophrenia spectrum personality (SSP) traits.

Results

We found that (1) MMN was reduced in patients (p < 0.001) and SSP subjects (p = 0.047) but not in relatives (p = 0.42); (2) there were augmented 1–20 Hz oscillations in patients (p = 0.02 to <0.001) during standard and deviant stimuli; (3) theta-alpha (5–12 Hz) oscillations had the strongest correlation to MMN in controls and relatives (ΔR² = 21.4–23.9%, all p < 0.001), while delta (<5 Hz) showed the strongest correlation to MMN in schizophrenia and SSP trait subjects; and, (4) MMN (h² = 0.56, p = 0.002) and theta-alpha (h² = 0.55, p = 0.004) were heritable traits.

Conclusions

Low frequency oscillations have a robust relationship with MMN and the relationship appears altered by schizophrenia; and schizophrenia patients showed augmented low frequency activities during the MMN paradigm.

Significance

The results encourage investigation of low frequency oscillations to elucidate the neurophysiological pathology underlying MMN abnormalities in schizophrenia.     

Spatial Analytic Phase Difference of EEG activity during anesthetic-induced unconsciousness

Objective

A number of studies provide supporting evidence for changes in synchronization during anesthetic-induced unconsciousness. This study investigates how anesthetic administration affects the widespread patterns of phase synchrony.

Methods

The recently introduced method of Spatial Analytic Phase Difference (SAPD) was used to measure changes in synchrony in the electroencephalogram (EEG) activity of 29 patients undergoing routine surgery. Analysis was performed over 9 frequency bands: (i) δ (1.5–3.5 Hz); (ii) θ (3.5–7.5 Hz); (iii) α1 (8–10 Hz); (iv) α2 (10.5–12 Hz); (v) β1 (12.5–18 Hz); (vi) β2 (18.5–21 Hz); (vii) β3 (21.5–30 Hz); (viii) γ1 (30.5–40 Hz); and (ix) γ2 (60–80 Hz).

Results

Anesthesia was characterized by (a) large and localized synchrony increases in mid-frequency bands (8–12 Hz), (b) smaller and widespread synchrony increases in higher frequency bands (30.5–40 Hz, 60–80 Hz), and (c) both increase and decrease of synchrony in low frequency bands (1.5–7.5 Hz).

Conclusions

This study supports anesthetic-induced changes in synchrony, with the inducement of persistent and reversible widespread γ synchrony being most prominent.

Significance

Our findings have implications in the study of consciousness, support existing literature in the field and contribute towards the theoretical understanding of the mechanisms behind loss of consciousness. Future investigations could result in a synchrony-based measure for monitoring the level of hypnosis of patients during surgery.     

Cortical sources of resting state EEG rhythms are abnormal in dyslexic children

Objective

Previous studies have been inconclusive whether dominant resting state alpha rhythms differ in amplitude in dyslexic subjects when compared to control subjects, being these rhythms considered as a reflection of effective cortical neural synchronization and cognition. Here we used a validated EEG source estimation to test the hypothesis that resting state alpha rhythms are abnormal in dyslexic subjects and are related to reading deficits.

Methods

Eyes-closed resting state electroencephalographic (EEG) data were recorded in 26 dyslexics (12 males, mean age of 11 years ± 0.5 standard error of mean, SEM) and 11 age-matched normal control subjects (8 males, mean age of 11 years ± 0.7 SEM). EEG rhythms of interest, based on individual alpha frequency peak, were the following: about 2–4 Hz (delta), 4–6 Hz (theta), 6–8 Hz (alpha 1), 8–10 Hz (alpha 2), and 10–12 Hz (alpha 3). For the higher frequencies, we selected beta 1 (13–20 Hz), beta 2 (20–30 Hz), and gamma (30–40 Hz). Cortical EEG sources were estimated by low resolution electromagnetic tomography (LORETA). LORETA solutions were normalized across all voxels and frequencies.

Results

Compared to the control children, the dyslexics showed lower amplitude of parietal, occipital, and temporal alpha 2 and alpha 3 sources. In the dyslexics, some of these sources were correlated to reading time of pseudo-words (parietal alpha 2, r = −0.56, p = 0.02; parietal alpha 3, r = −0.58, p = 0.02; temporal alpha 3, r = −0.57, p = 0.02); the higher the alpha power, the shorter the reading time.

Conclusions

Dyslexic children are characterized by limited abnormalities of resting state EEG rhythms as to topography (posterior regions) and frequency (alpha), which were related to phonological encoding (pseudo-words reading).

Significance

Dyslexia may be associated to some functional impairment of cortical neuronal synchronization mechanisms involved in the resting state condition.     

The wide variability of perospirone metabolism and the effect of perospirone on prolactin in psychiatric patients

Background

Perospirone was developed in Japan and is used for the treatment of schizophrenia and related illnesses. The authors investigated the relationship between the dosage of perospirone and the plasma levels of perospirone and its active metabolite, ID15036, and also evaluated the impact of the plasma concentrations of perospirone and ID15036 on the plasma prolactin level to examine whether perospirone or ID15036 affected the dopamine D₂ blockade, in psychiatric patients treated with perospirone.

Methods

The subjects consisted of 21 adults treated with perospirone (4–60 mg/day). The plasma perospirone and ID15036 levels were measured in 21 patients and serum prolactin levels were investigated in 10 male patients with schizophrenia.

Results

The plasma ID15036 level was higher than the plasma perospirone, and a positive correlation was observed between the dosage of perospirone and the ID15036 levels (p = 0.032). The 10 male patients showed a positive correlation between the plasma perospirone levels and plasma prolactin levels (r = 0.688, p = 0.028) and between the plasma ID15036 levels and prolactin levels (r = 0.775, p = 0.009).

Conclusion

The plasma levels of ID15036 may have a greater impact on the dopamine D₂ blockade than perospirone in patients treated with perospirone.     

Learning curve for percutaneous endoscopic lumbar discectomy depending on the surgeon's training level of minimally invasive spine surgery

Purpose

To evaluate the differences of learning curve for PELD depending on the surgeon’ s training level of minimally invasive spine surgery.

Methods

We retrospectively reviewed the medical records of 120 patients (surgeon A with his first 60 patients, surgeon B with his first 60 patients) with sciatica and single-level L4/5 disk herniation who underwent PELD by the two surgeons with different training level of minimally invasive spine surgery (Group A: surgeon with little professional training of PELD; Group B: surgeon with 2 years of demonstration teaching of PELD).

Results

Significant differences were observed in the operation time (p = 0.000), postoperative hospital stay (p = 0.026) and reoperation rate (p = 0.050) between the two groups. In the operation time, significant differences were observed between the 1–20 patients group and 41–60 patients group in Group B (p = 0.041), but there were no significant differences among the 1–20 patients group, 21–40 patients group and 41–60 patients group in Group A. In the postoperative hospital stay, the significant differences were observed in the 1–20 patients group between Group A and Group B (p = 0.011). Significant differences were observed between preoperative and postoperative VAS back score, VAS leg score and JOA score. Higher improvement in the VAS leg score was observed in Group B than Group A (p = 0.031). In the rate of reoperation, the significant difference was observed between the 1–20 patients group and 41–60 patients group in Group A (p = 0.028) but there were no significant differences among the 1–20 patients group, 21–40 patients group and 41–60 patients group in Group B.

Conclusions

The surgeons’ training level of minimally invasive spine surgery was an important factor for the success of PELD, especially the demonstration teaching of PELD for the new minimally invasive spine surgeons.     

The loudness dependence of the auditory evoked potential (LDAEP) in schizophrenia,bipolar disorder,major depressive disorder,anxiety disorder,and healthy controls

Background

Serotonergic dysfunction in schizophrenia, bipolar disorder, major depressive disorder, anxiety disorder, and healthy controls was evaluated by measuring the activity of the loudness dependence of the auditory evoked potential (LDAEP).

Methods

The 357 subjects who were evaluated comprised 55 normal controls, 123 patients with major depressive disorder, 37 with bipolar disorder, 46 with schizophrenia, 37 with panic disorder (PD), 31 with generalized anxiety disorder (GAD), and 28 with post-traumatic stress disorder (PTSD).

Results

LDAEP was significantly stronger in healthy controls than in patients with either bipolar disorder (p = 0.025) or schizophrenia (p = 0.008), and significantly stronger in patients with major depressive disorder than in those with bipolar disorder (p = 0.01) or schizophrenia (p = 0.03). LDAEP did not differ significantly between patients with major depressive disorder and healthy control subjects (p = 0.667), or between healthy control subjects and patients with anxiety disorder, including PD (p = 0.469), GAD (p = 0.664), and PTSD (p = 0.167).

Conclusion

The findings of the present study reveal that patients with major psychiatric disorders exhibit different strengths of LDAEP according to their serotonin-related pathology. Studies controlled for psychotropic medication, menstruation cycle, and smoking are needed.     

The EEG response to photic stimulation is not increased in alcohol-related seizures

Objective

To investigate the occipital EEG response to 18 and 24 Hz photic stimulation (the H-response) in alcohol-related seizures (ARS).

Method

Twenty-two ARS patients, 15 of whom had a withdrawal seizure (WS) were compared with patients with recent seizures of other causes: 21 patients with epilepsy, and 30 Alcohol Use Disorders Identification Test (AUDIT) negative patients with other seizures. EEG from 37 out-patients with epilepsy and 79 sciatica patents served as patient-controls. The spectral amplitude around 18 and 24 Hz and a new photic H-ratio (24/18 Hz relative amplitude) was calculated.

Results

The H-ratio was significantly reduced in the ARS group compared to the sciatica group. H-ratio reduction correlated with the AUDIT score in ARS patients (p = 0.02). No differences between WS and non-WS patients were found for H-response variables.

Conclusion

A dose–response relationship between AUDIT and the photic response H-ratio was observed in ARS patients. The EEG-driving response to 24 Hz flashes was not increased in ARS.

Significance

The relative decrease in 24 Hz photic response in ARS reflected drinking severity. The H-ratio is a candidate biomarker for ARS on the group level, although the moderate effect size precludes its use in individual patients.     

Lorazepam–diazepam protocol for catatonia in schizophrenia: A 21-case analysis

Objectives

Catatonia is a unique clinical phenomenon characterized by concurrent motor, emotional, vegetative and behavioral signs. Benzodiazepines (BZD) and electroconvulsive therapy (ECT) can rapidly relieve catatonic signs. The lorazepam–diazepam protocol presented here has been proven to relieve catatonia in schizophrenia within a day.

Methods

From July 2002 to August 2011, schizophrenic patients requiring psychiatric intervention for catatonia in Kaohsiung Chang Gung Memorial Hospital were studied by medical chart review. The study used the Bush–Francis Catatonia Rating Scale (BFCRS). Patients receiving the lorazepam–diazepam protocol were identified.

Results

The survey included 21 patients (eight males and 13 females) with a mean age of 30.3 ± 12.6 years. Mean duration of schizophrenia was 4.7 ± 5.6 years. Thirteen (61.9%) patients responded within 2 h, 18 (85.7%) responded within one day, and all became catatonia-free within a week. Mean BFCRS score was 9.9 ± 3.0 before treatment. Patients that responded with a single intramuscular lorazepam injection had mean BFCRS score of 8.9 ± 2.8, significantly lower than the mean score (11.6 ± 2.5) of the rest of the patients (p = 0.034).

Conclusions

The lorazepam–diazepam protocol can rapidly relieve retarded catatonia in schizophrenia. Most patients became catatonia-free within one day but some may require up to a week. ECT should be considered if the protocol fails.     

Association of the manganese superoxide dismutase gene Ala–9Val polymorphism with clinical phenotypes and tardive dyskinesia in schizophrenic patients

Objective

Several recent studies that have investigated the genetic association between the manganese superoxide dismutase (MnSOD) gene Ala–9Val single-nucleotide polymorphism (SNP) and tardive dyskinesia (TD) have produced conflicting results. This study was to investigate whether this SNP was associated with clinical phenotypes and antipsychotic-induced tardive dyskinesia (TD) in schizophrenia in a genetically homogeneous Han Chinese inpatient population.

Methods

Genotyping was performed for the MnSOD gene Ala–9Val SNP in Chinese schizophrenia patients with (n = 176) and without TD (n = 346). The severity of TD was assessed using the abnormal involuntary movement scale (AIMS), and psychopathology using the Positive and Negative Syndrome Scale (PANSS).

Results

The frequencies of genotypes and alleles did not differ significantly between schizophrenic patients with and without TD (both p > 0.05). Also, there was no significant difference in the AIMS total score between the Val/Val and Ala allele carrier groups (p > 0.05). However, the PANSS negative symptom subscore was significantly higher in patients with Val/Val genotype (21.8 ± 7.3) than those with Ala alleles (20.1 ± 7.7) (t = 2.32, p = 0.03).

Conclusion

While the MnSOD gene Ala–9Val polymorphism did not play a major role in the susceptibility to TD in schizophrenic patients, it might be associated with negative symptoms of schizophrenia.     

A genetic schizophrenia-susceptibility region located between the ANKK1 and DRD2 genes

Background

The gene coding for the D2 dopamine receptor (DRD2) is considered to be one of the most pertinent candidate genes in schizophrenia. However, genetic studies have yielded conflicting results whereas the promising TaqIA variant/rs1800497 has been mapped in a novel gene, ANKK1.

Methods

We investigated eleven single nucleotide polymorphisms (SNPs) spanning the DRD2 and ANKK1 genes, using both a case–control association study comparing 144 independent patients to 142 matched healthy subjects, and a transmission disequilibrium test in 108 trios. This classical genetic study was coupled with a cladistic phylogeny-based association test of human variants, and with an interspecies evolution study of ANKK1.

Results

Case–control study, followed by a 108 trios family-based association analysis for replication, revealed an association between schizophrenia and the ANKK1 rs1800497 (p = 0.01, Odds Ratio = 1.5, 95% Confidence Interval = 1.1–2.2), and the intergenic rs2242592 (p = 2 · 10^− 4, OR = 1.8, 95%CI = 1.3–2.5). A significant SNP–SNP interaction was also found (p < 10^− 5, OR = 2.0, 95%CI = 1.6–2.5). The phylogeny-based association test also identified an association between both these polymorphisms and schizophrenia. Finally, interspecies comparison of the sequences from chimpanzee, orangutan, rhesus macaque and human species suggested specific involvement of ANKK1 in the human lineage.

Conclusions

Intergenic rs2242592 appears to be involved in the genetic vulnerability to schizophrenia, whereas the ANKK1 rs1800497 appears to have a modifying rather than causative effect. Finally, ANKK1 may be a specific human lineage-trait involved in a specific human disease, schizophrenia.     

Effects of repetition rate of bone-conducted vibration on ocular and cervical vestibular-evoked myogenic potentials

Objective

This study applied bone-conducted vibration (BCV) stimuli at various repetition rates to investigate the effects of repetition rate on both ocular and cervical vestibular-evoked myogenic potentials (oVEMPs and cVEMPs).

Methods

Twenty-five healthy subjects underwent oVEMP tests in BCV mode at repetition rates of 1, 5, 10, 20, 30 and 40 Hz. The optimal repetition rates (5, 10 and 20 Hz) for oVEMPs were also adopted to elicit cVEMPs, and 20 Hz stimuli were further evaluated in pathological ears.

Results

At repetition rates of 1, 5, 10, 20, 30 and 40 Hz, the prevalence of clear oVEMPs were 100% in groups of 5, 10 and 20 Hz, with no significant differences in the mean nI latency, but the mean nI–pI amplitude of the 20 Hz group showed significantly larger. For the BCV–cVEMPs, 5, 10 and 20 Hz stimuli yielded similar information. Clinically, the BCV mode at 20 Hz stimuli was also appropriate for evaluating VEMPs in ears of vestibular schwannoma.

Conclusions

The BCV mode at a repetition rate of 20 Hz is recommended for the mass detection of VEMPs.

Significance

Eliciting VEMPs in BCV mode using 20 Hz stimuli takes a short time and may trigger a high prevalence with large amplitude.     

Ambulatory assessments of psychological and peripheral stress-markers predict birth outcomes in teen pregnancy

Objective

Pregnant adolescents have high rates of poor birth outcomes, but the causes are unclear. We present a prospective, longitudinal study of pregnant adolescents assessing associations between maternal psychobiological stress indices and offspring gestational age at birth and birthweight.

Method

Healthy nulliparous pregnant adolescents were recruited (n = 205) and followed during pregnancy. Ambulatory assessments over 24 h of perceived psychological stress (collected every 30 min) and salivary cortisol (6 samples) and a summary questionnaire, the Perceived Stress Scale, were collected at three time points (13–16, 24–27, and 34–37 gestational weeks). Corticotropin-releasing hormone, C-reactive protein, and interleukin 6 were assayed from blood taken at the latter 2 sessions. A final sample of 119 participants was selected for analyses.

Results

The ambulatory assessment of perceived psychological stress was positively correlated with the Perceived Stress Scale (r = .20, p = .03) but neither was associated with any of the biological assays (all ps > .20). Based on backward selection regression models that included all stress variables and relevant covariates, the ambulatory assessments of perceived psychological stress and cortisol — though not the Perceived Stress Scale — were negatively associated with gestational age at birth (F(4, 107) = 3.38, p = .01) while cortisol was negatively related to birthweight (F(5, 107) = 14.83, p < .0001).

Conclusions

Targeted interventions to reduce psychological and biological indicators of heightened stress during pregnancy may have positive public health benefits for the offspring given the associations of shortened gestation and lower birthweight with risk for poor mental and physical health outcomes.     

Efficacy and safety of noradrenalin reuptake inhibitor augmentation therapy for schizophrenia: A meta-analysis of double-blind randomized placebo-controlled trials

Background

We performed an updated meta-analysis of noradrenalin reuptake inhibitor (NRI) augmentation therapy in patients with schizophrenia treated with antipsychotics based on a previous meta-analysis (Singh et al.).

Methods

PubMed, Cochrane Library databases, and PsycINFO citations were searched from their inception to June 10, 2013 without language restrictions. We conducted a systematic review and meta-analysis of individual patient data from randomized controlled trials comparing NRI augmentation therapy with placebo. The outcome measure for efficacy was the psychopathology of schizophrenia and the measures for safety were discontinuation rate and several side effects. We used standardized mean differences (SMD) to estimate treatment effects for continuous variables, and risk ratios (RR) for dichotomous variables, with their 95% confidence intervals (CIs). A random-effects model was used.

Results

Nine studies (4 atomoxetine studies, 3 reboxetine studies, 1 reboxetine–betahistine combination study and 1 mazindol study, total n = 298) were identified. No statistically significant effects of NRI augmentation therapy on overall (p = 0.90), positive (p = 0.81), and negative (p = 0.89) symptoms were found. NRI augmentation therapy was marginally superior to placebo for efficacy of depressive symptoms (SMD = −1.08, p = 0.05). Dropout due to all-cause (p = 0.70), inefficacy (p = 0.64), or adverse events (p = 0.18) was similar in both groups. NRI augmentation therapy showed a significantly lower increase or larger reduction in body weight than placebo (SMD = −0.47, p = 0.03). Reboxetine augmentation was associated with less weight gain that placebo in antipsychotic treated schizophrenia patients (SMD = −0.78, p = 0.0001).

Conclusion

NRIs may exert an effect on depressive symptoms, and seem to be well-tolerated treatments.     

Cortical sources of resting-state EEG rhythms are abnormal in naïve HIV subjects

Objective

The aim of the study was to test the hypothesis that cortical sources of resting-state electroencephalographic (EEG) rhythms show peculiar frequency/spatial features in naïve human subjects with human immunodeficiency virus (HIV) compared to healthy control subjects.

Methods

Resting-state eyes-closed EEG data were recorded in 18 naïve HIV subjects (15 males; mean age 39 years ± 2.0 standard error of mean, SEM) and in 18 age-matched cognitively normal subjects (15 males; 38.7 years ± 2.2 SEM). EEG rhythms of interest were delta (2–4 Hz), theta (4–8 Hz), alpha1 (8–10 Hz), alpha2 (10–12 Hz), beta1 (13–20 Hz) and beta2 (20–30 Hz). Cortical EEG sources were estimated by normalised, low-resolution electromagnetic tomography (LORETA).

Results

Mini Mental State Evaluation (MMSE) score was lower in HIV (26.5 ± 0.7 SEM) than in healthy (29.2 ± 0.5 SEM) subjects (p < 0.05). Central and parietal delta sources showed higher amplitude in the HIV than in control subjects. Furthermore, topographically widespread, cortical sources of resting-state alpha rhythms were lower in amplitude in HIV subjects than in control subjects.

Conclusions

The present results suggest that topography and frequency of the cortical sources of resting-state EEG rhythms can distinguish groups of HIV and control subjects.

Significance

These results encourage future studies in an enlarged cohort of HIV subjects to test the hypothesis that the present methodological approach provides clinically useful information for an early detection of the effect of HIV infection on brain and cognitive functions.     

Slow spindles’ cortical generators overlap with the epileptogenic zone in temporal epileptic patients: An electrical source imaging study

Objective

To determine whether temporal epileptic patients and normal volunteers display similar sleep spindles’ cortical generators as determined by electrical source imaging (ESI), and whether such generators overlap in epilepsy patients with the epileptogenic zone identified by ESI.

Methods

Twelve healthy subjects and twelve temporal lobe pharmaco-resistant epileptic patients underwent a 256-channel EEG recording during a daytime nap. Sleep spindles were analyzed off line, distinguishing slow (10–12 Hz) and fast (12–14 Hz) ones, and the final averaged signal was projected onto a MNI (Montreal Neurological Institute) space to localize cortical generators. The same procedure was performed for averaged epileptic spikes, obtaining their cortical source. Intra- and inter-group statistical analyses were conducted.

Results

Multiple, concomitant generators were detected in both populations for slow and fast spindles. Slow spindles in epileptics displayed higher source amplitude in comparison to healthy volunteers (Z = 0.001), as well as a preferential localization over the affected temporal cortices (p = 0.039). Interestingly, at least one of slow spindles’ generators overlapped with the epileptogenic zone.

Conclusion

Slow spindles, but not fast ones, in temporal epilepsy are mainly generated by the affected temporal lobe.

Significance

These results point to the strict relation between sleep and epilepsy and to the possible cognitive implications of spikes arising from memory-encoding brain structures.     

Behavioral health mediators of the link between posttraumatic stress disorder and dyslipidemia

Objectives

Posttraumatic stress disorder (PTSD) has been linked to dyslipidemia, which is a major risk factor for coronary artery disease. Although this link is thought to reflect response to heightened stress, behavioral health risks, including smoking, alcohol dependence, and poor sleep quality, may mediate the relationship between PTSD and dyslipidemia.

Methods

To test this hypothesis, serum lipid levels were collected from 220 young adults (18–39 years old), 103 of whom were diagnosed with PTSD.

Results

PTSD and associated depressive symptoms were negatively related to high-density lipoprotein cholesterol (HDL-C), p = .04, and positively related to triglyceride (TG) levels, p = .04. Both associations were mediated by cigarette consumption and poor sleep quality, the latter of which accounted for 83% and 93% of the effect of PTSD and depression on HDL-C and TG, respectively.

Conclusions

These results complement recent findings highlighting the prominence of health behaviors in linking PTSD with cardiovascular risk.     

Neurophysiological evidence of impaired musical sound perception in cochlear-implant users

Objective

Music perception with a cochlear implant (CI) can be unsatisfactory because current-day implants are primarily designed to enable speech discrimination. The present study aimed at evaluating electrophysiological correlates of musical sound perception in CI users to help achieve the long-term goal of improved restoration of hearing in those individuals.

Methods

Auditory discrimination accuracy in adult CI users (n = 12) and matched normal-hearing controls (n = 12) was measured by behavioral discrimination tasks and mismatch negativity (MMN) recordings. Discrimination profiles were obtained by using a set of clarinet sounds (original/vocoded) varying along different acoustic dimensions (frequency/intensity/duration) and deviation magnitudes (four levels).

Results

Behavioral results and MMN recordings revealed reduced auditory discrimination accuracy in CI users. An inverse relationship was found between MMN amplitudes and duration of profound deafness.

Conclusions

CI users have difficulties in discriminating small changes in the acoustic properties of musical sounds. The recently developed multi-feature MMN paradigm (Pakarinen et al., 2007) can be used to objectively evaluate discrimination abilities of CI users for musical sounds.

Significance

Measuring auditory discrimination functions by means of a multi-feature MMN paradigm could be of substantial clinical value by providing a comprehensive profile of the extent of restored hearing in CI users.     

Translation into Arabic and validation of the Schedule for the Assessment of Insight–Expanded Version (SAI-E) for use in Tunisia

Background

The Schedule for the Assessment of Insight–Expanded Version (SAI-E) consists of 11 items that encompass: awareness of having a mental illness, ability to rename psychotic phenomena as abnormal, and compliance with treatment.

Aims

To translate into Arabic and validate the Tunisian version of this instrument.

Method

The Arabic translation of the SAI-E was obtained by the “forward/backward translation” method. Adaptations were made after a pilot study involving 20 outpatients with schizophrenia and after taking account the opinions of 15 experts in psychiatry.For validation, 150 outpatients suffering from schizophrenia were recruited by a random drawing in the psychiatric department in Sousse (Tunisia).For factor analysis, principal components analysis and Varimax rotation were adopted. Convergent validity was assessed by correlating the translated scale with the G12 item (lack of judgment and awareness of the disease) of the positive and Negative Syndrome Scale (PANSS).Internal consistency was assessed by Cronbach alpha coefficient and inter-rater reliability was assessed by the use of intra-class correlation coefficient (ICC).

Results

Regarding construct validity, factor analysis revealed three factors that were responsible for 70.2% of the variance.As for concurrent validity, we found a negative correlation between the score of the SAI-E and that of the G12 item of the PANSS (r = − 0.82 and p < 10⁻³).The study of internal consistency between the 11 items was found to be good (α = 0.82). The test–retest reliability was satisfactory (r = 0.8, p < 10⁻³), and so was inter-rater reliability (ICC = 0.84).

Conclusion

In the Tunisian cultural context, the SAI-E presented three factors with good consistency and an inter-rater reliability compatible with the insight dimensions that are intended to be evaluated.     

Genetic polymorphisms in the dopamine-2 receptor (DRD2), dopamine-3 receptor (DRD3), and dopamine transporter (SLC6A3) genes in schizophrenia: Data from an association study

Objective

To investigate the association between dopaminergic polymorphisms [DRD2 −141C Ins/Del, DRD3 Ser9Gly, and SLC6A3 VNTR] and schizophrenia.

Methods

Two hundred and eighty-eight outpatients with schizophrenia (DSM-IV criteria) [mean age (SD) = 36.4 (12.4), 60.1% males] and 421 unrelated healthy controls [mean age (SD) = 40.6 (11.3), 51.3% males] from a homogeneous Spanish Caucasian population were genotyped using standard methods.

Results

There was a significant difference in genotype distribution for the DRD2 −141C Ins/Del polymorphism [(χ² (2) = 12.35, corrected p = 0.012]. The − 141C Del allele was more common in patients than in controls [0.19 vs. 0.13; χ² (1) = 9.14, corrected p = 0.018, OR (95% CI) = 1.57 (1.17–2.10)]. Genotype and allele distributions for DRD3 Ser9Gly and SLC6A3 VNTR polymorphisms were similar in both groups. However, there was tentative evidence of an interaction effect between DRD3 Ser9Gly and SLC6A3 VNTR [Wald = 9.56 (4), p = 0.049]. Compared to the SLC6A3 10/10 genotype category, the risk of schizophrenia was halved among those with 9/10 [OR = 0.51 (95% CI = 0.30–0.89), p = 0.017]. This protective effect was only present in combination with DRD3 Ser/Ser genotype because of the significant interaction between 9/10 and both Ser/Gly [OR = 2.45 (95% CI = 1.16–5.17), p = 0.019] and Gly/Gly [OR = 3.80 (95% CI = 1.24–11.63), p = 0.019].

Conclusions

This study provides evidence that a genetic variant in the DRD2 gene and possible interaction between DRD3 and SLC6A3 genes are associated with schizophrenia. These findings warrant examination in replication studies.     

Intravenous rt-PA in patients with ischaemic stroke and renal dysfunction

Objective

Renal dysfunction (RD) increases risk for ischaemic stroke (IS). The impact of RD on the effects of iv-thrombolysis in the Caucasian population has not been fully determined.

Aims

To evaluate the associations between RD and the outcome of iv-thrombolysis in Caucasian patients with IS.

Methods

The observational, multicentre study included 404 patients with IS who were treated with iv-thrombolysis. RD was defined as estimated glomerular filtration rate ≤60 ml/min/1.73 m². Outcome was assessed with modified Rankin Score at 3 months after the stroke onset.

Results

Medians baseline NIHSS score did not differ between groups of patients with and without RD (12.0 vs. 11.0 pts, p = 0.33). Unfavourable outcome was found in 52.1% of patients with and in 41.2% of patients without RD (p = 0.05), mortality was higher in patients with RD (29.9% vs. 14.3%, p < 0.001), and the presence of haemorrhagic transformation (HT) did not differ between the groups (17.1% vs. 17.1% respectively, p = 0.996). A multivariate analysis showed no impact of RD on the unfavourable outcome (OR 0.98; 95%CI 0.88–1.10), mortality (OR 0.92; 95%CI 0.81–1.05) or presence of HT (OR 1.03; 95%CI 0.90–1.18).

Conclusions

We found no impact of RD on the safety and efficacy of iv-thrombolysis in Caucasian patients with IS.