bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phenomenology associated with age at onset in patients with bipolar disorder at their first psychiatric hospitalization
Authors: Patel Nick C , DelBello Melissa P , Keck Paul E , Strakowski Stephen M 
Published: January 2006

Objective:  To compare the clinical presentation of patients with early‐onset (age <18 years) and typical‐onset (age 20–30 years) bipolar disorder at the time of first hospitalization.Methods:  Patients, aged 12–45 years at their first psychiatric hospitalization, with a DSM‐IV diagnosis of bipolar disorder, manic or mixed, were evaluated on measures of manic, depressive, and positive psychotic symptoms. Differences in symptom profiles between early‐ and typical‐onset groups were examined.Results:  One hundred three early‐onset and 58 typical‐onset patients were compared. Mixed episodes were more common in the early‐onset group, while psychotic features and current substance use were more common in the typical‐onset group. There was no significant difference in manic symptom severity ratings between early‐ and typical‐onset groups (F = 1.8, df = 11, 144, p = 0.06). However, these groups differed in depressive (F = 4.2, df = 16, 139, p < 0.001) and positive psychotic (F = 2.8, df = 16, 139, p = 0.001) symptom profiles. Typical‐onset bipolar patients reported more severe weight loss and formal thought disorder compared with early‐onset patients.Conclusions:  Depressive and positive psychotic symptoms may differ in association with age at onset among patients with bipolar disorder. Additional studies are necessary to determine whether homogeneous phenotypes of bipolar disorder can be delineated based upon age at onset.
Fronto‐temporal function may distinguish bipolar disorder from schizophrenia
Authors: Frangou S , Dakhil N , Landau S , Kumari V 
Published: January 2006

Objectives:  There is evidence for differential neural alterations within the prefrontal cortex (PFC) in bipolar disorder I (BDI) and schizophrenia that may translate into different cognitive deficits. Our objective was to compare the cognitive profile of stable BDI and schizophrenic patients using neuropsychological tasks which utilize frontal systems but differ in terms of the exact neural circuits and cognitive processes involved.Methods:  We studied 43 patients with BDI, 54 with schizophrenia and 46 matched healthy participants. All participants completed (i) the Wisconsin Card Sorting Test (WCST) which is known to recruit the dorsal and ventral PFC, (ii) the verbal fluency task (VFT), which engages frontal‐temporal regions, and (iii) the Stroop Colour Word Test (SWCT) which depends on the integrity of the cingulo‐frontal network. A series of multivariate analyses examined differences between the cognitive profiles of BD and schizophrenic patients relative to that of healthy participants controlling for general intellectual ability and gender.Results:  Bipolar disorder I patients showed minimal verbal fluency impairment while schizophrenic patients demonstrated marked deficits on this task relative to the control and BDI groups. The two patient groups had comparable performance on the WCST. In the SWCT, schizophrenic patients showed impairment in both congruent and incongruent conditions while BD patients had deficits only in the latter.Conclusions:  Absence of significant verbal fluency abnormalities and by inference dysfunction in the associated fronto‐temporal circuitry may distinguish BDI from schizophrenia. Both disorders may show impairment in tasks involving cingulo‐frontal networks with evidence of greater cingulate dysfunction in schizophrenia.
Neurocognitive impairment in euthymic young adults with bipolar spectrum disorder and recurrent major depressive disorder
Authors: Smith Daniel J , Muir Walter J , Blackwood Douglas HR 
Published: January 2006

Objective:  Patients with remitted major depressive disorder (MDD) and bipolar disorder have persistent impairments in executive function and verbal memory that may represent endophenotypic abnormalities. In this study, we examine neurocognitive function in a sample of euthymic young adults with bipolar spectrum disorder (BSD) (Can J Psychiatry 2002; 47: 125–134) and compare this to well‐matched samples of young adults with recurrent MDD and controls.Method:  Twenty‐one euthymic young adult patients with BSD were compared with 42 young adult patients with MDD and 33 controls on a neuropsychological battery assessing attention, executive function and verbal memory.Results:  Patients with BSD were significantly more impaired than MDD patients and controls on tests of executive function and verbal memory. MDD patients did not differ significantly from controls on verbal memory function but performed less well on a test of executive function.Conclusion:  Euthymic young adults with BSD had greater impairment on neurocognitive measures associated with prefrontal and hippocampal function than MDD patients and controls. This is a reflection of a strong bipolar diathesis in the BSD group rather than being a consequence of a more severe unipolar illness.
Topiramate monotherapy in the management of acute mania: results of four double‐blind placebo‐controlled trials
Authors: Kushner Stuart F , Khan Akbar , Lane Rosanne , Olson William H 
Published: January 2006

Objective:  To evaluate the efficacy and tolerability of topiramate monotherapy in adults with acute manic or mixed episodes of bipolar I disorder.Methods:  In four trials, adults hospitalized with acute mania, a diagnosis of bipolar I disorder, history of ≥1 previous manic or mixed episodes, and ≥20 Young Mania Rating Scale (YMRS) score were randomized to double‐blind treatment with topiramate (target doses: 200, 400, or 600 mg/day) or placebo; two trials included an active comparator (lithium, 1500 mg/day). The core study duration in all trials was 3 weeks; three trials also had 9‐week double‐blind extensions. The primary efficacy variable was mean change from baseline in YMRS in the core 3‐week study.Results:  Changes in YMRS score during 3 weeks were not significantly different for topiramate versus placebo (mean YMRS reductions, −5.1 to −8.4). Mean YMRS reductions in lithium‐treated groups were significantly greater (p ≤ 0.001 versus placebo and topiramate). A similar pattern was observed after 12 weeks of double‐blind treatment in studies with double‐blind extensions. Paresthesia, appetite decrease, dry mouth, and weight loss were more frequently associated with topiramate than with placebo.Conclusions:  These studies do not support the efficacy of topiramate as monotherapy in acute mania or mixed episodes in adults with bipolar I disorder. Topiramate was not associated with mood destabilization measured as mania exacerbation or treatment‐emergent depression. Lithium was confirmed as an effective therapy in this population.
Diagnostic subtypes of bipolar disorder in older versus younger adults
Authors: Kessing Lars Vedel 
Published: January 2006

Objective:  To investigate differences in diagnostic subtypes of bipolar disorder as according to ICD‐10 between patients whose first contact with psychiatric health care occurs late in life (over 50 years of age) and patients who have first contact earlier in life (50 years of age or below).Methods:  From 1994 to 2002 all patients who received a diagnosis of a manic episode or bipolar disorder at initial contact with the mental healthcare system, whether outpatient or inpatient, were identified in Denmark's nationwide register.Results:  A total of 852 (49.6%) patients, who were over age 50, and 867 patients, who were 50 or below, received a diagnosis of a manic episode or bipolar disorder at the first contact ever. Older inpatients presented with psychotic symptoms (35.4%) significantly less than younger inpatients (42.6%) due specifically to a lower prevalence of manic episodes with psychotic symptoms. Conversely, older inpatients more often presented with severe depressive episodes with psychotic symptoms than younger inpatients (32.0% versus 17.0%). Among outpatients, no significant differences were found between patients older than 50 years and patients 50 years of age or younger. However, a bimodal distribution of age at first outpatient contact was found with an intermode of 65 years and outpatients older than 65 years more often presented with severe depressive episodes with psychosis.Conclusions:  Bipolar patients who are older at first psychiatric hospitalization (>50 years) present less with psychotic manic episodes and more with severe depressive episodes with psychosis than younger patients. The distribution of age at first outpatient contact is bimodal with an intermode of 65 years and outpatients older than 65 years more often present with severe depressive episodes with psychosis.
Ethnic differences in symptom presentation of youths with bipolar disorder
Authors: Patel Nick C , DelBello Melissa P , Strakowski Stephen M 
Published: January 2006

Objective:  To compare symptom profiles of African‐American and white adolescents with a diagnosis of bipolar disorder.Method:  Adolescents, aged 12–18 years at their first psychiatric hospitalization, with a DSM‐IV diagnosis of bipolar disorder, manic or mixed, were evaluated on measures of manic, depressive, and positive symptoms of psychosis. Ethnic differences in symptom profiles were examined using multivariate analysis of covariance, and specific symptoms contributing to the difference were analyzed.Results:  Ethnic differences existed in manic and positive symptom profiles, but not depressive symptoms. Compared with the white cohort, African‐American youths were diagnosed more frequently as having psychotic features, and had higher ratings for auditory hallucinations.Conclusions:  Similar to adults, symptom expression in adolescent bipolar disorder may differ between ethnic groups. Future studies are needed to replicate these findings and explore possible explanations.
Neuropsychological impairment in bipolar disorder: the relationship with glucocorticoid receptor function
Authors: Watson Stuart , Thompson Jill M , Ritchie James C , Nicol Ferrier I , Young Allan H 
Published: January 2006

Objective:  Basal levels of glucocorticoids, such as cortisol, are generally unaltered in bipolar disorder. However, neuroendocrine tests of glucocorticoid receptor (GR) function such as the dexamethasone suppression test (DST) are frequently abnormal. Neuropsychological impairment is well documented in healthy volunteers after administration of glucocorticoids and in patients with bipolar affective disorder. This suggests a potential link between neuropsychological and hypothalamic‐pituitary‐adrenal axis function. We examined the hypothesis that neuropsychological impairment in bipolar disorder is associated with abnormal GR function.Methods:  Seventeen euthymic bipolar patients and 16 controls completed tests of verbal declarative and working memory (WM) tests and the DST. The correlation between neuroendocrine and neuropsychological function was examined.Results:  Bipolar patients made significantly more errors of omission and commission on the WM paradigm and demonstrated impaired verbal recognition memory. Patients’ post‐dexamethasone cortisol correlated with WM commission errors (rs = 0.64, p = 0.0006). No such relationship was evident in controls.Conclusion:  Deficits in declarative memory and WM are evident in patients with bipolar disorder. The deficit in retrieval accuracy from WM appears to be correlated with abnormal GR function.
Stroop performance in bipolar disorder: further evidence for abnormalities in the ventral prefrontal cortex
Authors: Kronhaus Dina M , Lawrence Natalia S , Williams Andrew M , Frangou Sophia , Brammer Michael J , Williams Steve CR , Andrew Christopher M , Phillips Mary L 
Published: January 2006

Objectives:  Bipolar patients are impaired in Stroop task performance, a measure of selective attention. Structural and functional abnormalities in task‐associated regions, in particular the prefrontal cortex (PFC), have been reported in this population. We aimed to examine the relationship between functional abnormalities, impaired task performance and the severity of depressive symptoms in bipolar patients.Methods:  Remitted bipolar patients (n = 10; all medicated), either euthymic or with subsyndromal depression, and age‐matched control subjects (n = 11) viewed 10 alternating blocks of incongruent Stroop and control stimuli, naming the colour of the ink. Neural response was measured using functional magnetic resonance imaging. We computed between‐group differences in neural response and within‐group correlations with mood and anxiety.Results:  There were no significant between‐group differences in task performance. During the Stroop condition, controls demonstrated greater activation of visual and dorsolateral and ventrolateral prefrontal cortical areas; bipolar patients demonstrated relative deactivation within orbital and medial prefrontal cortices. Depression scores showed a trend towards a negative correlation with the magnitude of orbitofrontal cortex deactivation in bipolar patients, whereas state anxiety correlated positively with activation of dorsolateral PFC and precuneus in controls.Conclusions:  Our findings confirm previous reports of decreased ventral prefrontal activity during Stroop task performance in bipolar patients, and suggest a possible negative correlation between this and depression severity in bipolar patients. These findings further highlight the ventromedial PFC as a potential candidate for illness related dysfunction in bipolar disorder.
Affective instability as rapid cycling: theoretical and clinical implications for borderline personality and bipolar spectrum disorders
Authors: MacKinnon Dean F , Pies Ronald 
Published: January 2006

Objectives:  The Diagnostic and Statistical Manual of Mental Disorders guidelines provide only a partial solution to the nosology and treatment of bipolar disorder in that disorders with common symptoms and biological correlates may be categorized separately because of superficial differences related to behavior, life history, and temperament. The relationship is explored between extremely rapid switching forms of bipolar disorder, in which manic and depressive symptoms are either mixed or switch rapidly, and forms of borderline personality disorder in which affective lability is a prominent symptom.Methods:  A MedLine search was conducted of articles that focused on rapid cycling in bipolar disorder, emphasizing recent publications (2001–2004).Results:  Studies examined here suggest a number of points of phenomenological and biological overlap between the affective lability criterion of borderline personality disorder and the extremely rapid cycling bipolar disorders. We propose a model for the development of ‘borderline’ behaviors on the basis of unstable mood states that sheds light on how the psychological and somatic interventions may be aimed at ‘breaking the cycle’ of borderline personality disorder development. A review of pharmacologic studies suggests that anticonvulsants may have similar stabilizing effects in both borderline personality disorder and rapid cycling bipolar disorder.Conclusions:  The same mechanism may drive both the rapid mood switching in some forms of bipolar disorder and the affective instability of borderline personality disorder and may even be rooted in the same genetic etiology. While continued clinical investigation of the use of anticonvulsants in borderline personality disorder is needed, anticonvulsants may be useful in the treatment of this condition, combined with appropriate psychotherapy.
Cross‐Sectional and Longitudinal Studies of the Development of Group Differences in Acoustic Features of Coo Calls in Two Groups of Japanese Macaques
Authors: Tanaka Toshiaki , Sugiura Hideki , Masataka Nobuo 
Published: January 2006

AbstractJapanese macaques,Macaca fuscata, frequently utter coo calls to maintain vocal contact. Cross‐sectional and longitudinal comparisons were conducted on the acoustic features of coo vocalizations of two groups ofM. fuscata, Yakushima and Ohirayama groups, to explore the possibility of vocal plasticity. These two groups derive from the same local population but have been separated for more than 34 yr. The Yakushima group is non‐provisioned, while the Ohirayama group is provisioned. Initially, coo calls in the two groups were compared cross‐sectionally in females ranging from 0 to 18 yr. Mean values of the four variables studied (start, end, maximum, and minimum frequencies) were consistently lower in all age groups of the Ohirayama individuals compared with the Yakushima individuals. Secondly, longitudinal comparisons were conducted on individuals in the 1–4 yr after birth. Mean values of the five frequency variables studied (start, end, maximum, minimum and average frequencies) were again consistently lower in all age groups of Ohirayama compared with Yakushima individuals, although mean values of both groups gradually declined with an increase in age. Inter‐group differences were significant at all ages in minimum frequency and at the first, second and third years in start frequency. Longitudinal comparisons of individuals aged 4–11 mo were also conducted. Regarding the four variables that differed between the two groups in the cross‐sectional study, the mean values of minimum and start frequency did not differ significantly between the two groups at 4–5 mo, but were significantly lower in Ohirayama individuals aged 7–8 and 9–11 mo. Although provisioning may have had an effect on the weight difference between the groups, and consequently on vocalization frequency, these results suggest that the inter‐group differences in coo call features form approximately 6–7 mo after birth as a result of vocal plasticity.
Does Temporal Variation in Predation Risk Influence the Intensity of Antipredator Responses? A Test of the Risk Allocation Hypothesis
Authors: Mirza Reehan S. , Mathis Alicia , Chivers Douglas P. 
Published: January 2006

AbstractTemporal variation in predation risk may fundamentally influence antipredator responses of prey animals. To maximize lifetime fitness, prey must be able to optimize energy gain and minimize predation risk, and responses to current levels of risk may be influenced by background levels of risk. A ‘risk allocation’ model has recently been proposed to predict the intensity of antipredator responses that should occur as predation risk varies over time. Prey animals from high‐risk environments should respond to predators with relatively low intensities of antipredator behaviour because long periods of antipredator behaviour may result in unacceptable decreases in levels of foraging activity. Moreover, animals that are under frequent risk should devote more energy to foraging during brief pulses of safety compared with animals under infrequent attack. In this study, we experimentally tested the risk allocation hypothesis. We exposed juvenile rainbow trout, Oncorhynchus mykiss, to three levels of risk (high, moderate and low) crossed with two levels of temporal variation (exposed to risk three times a day and once a day). In accordance with the model, we found that trout exposed to risky situations more frequently responded with significantly less intense antipredator behaviour than trout exposed to risk infrequently. The intensity of response of trout exposed to moderate risk three times a day decreased to levels similar to situations of no risk. However, in contrast to the second prediction of the model, animals under frequent risk were not more active during periods of safety compared with animals under infrequent risk. Although behaviour in the face of predation risk was dependent on the broader temporal context in which risk varied, the specific predictions of the risk allocation model were only partly supported.
Gender Differences in Owners Interacting with Pet Dogs: An Observational Study
Authors: Prato‐Previde Emanuela , Fallani Gaia , Valsecchi Paola 
Published: January 2006

AbstractMany studies show that people form strong affectional bonds with their dogs, treating them like family members or children. The present study investigates differences between women and men owners during interactions with their dogs, in a situation designed to investigate attachment and, thus, to promote emotional and affective responses: the Ainsworth's Strange Situation. Twenty‐five dog owners, 10 men and 15 women, were observed during free interactions with their pets in an adapted version of the ‘strange situation procedure’. Their behaviour towards their pets was videorecorded. Talking to the dog was evaluated together with the occurrence of affiliative and play behaviours. The owner's level of attachment to the dog was assessed using a questionnaire. Women and men differed in the use of verbal communication. Women talked more than men and had a shorter latency in starting talking. Their utterances resembled more closely infant‐directed speech or ‘motherese’. In contrast, there were no clear gender differences in affiliative and play behaviours. Both women and men engaged in play with their dogs and provided physical comfort. No differences emerged in the level of attachment reported by women and men owners in the questionnaire. These data support the hypothesis that the behaviour of modern pet owners towards their dogs is an interspecific parental behaviour, and suggest that behaviours evolved to provide care and comfort to human infants have been co‐opted for interacting with other social partners. The difference in verbal communication between women and men is in agreement with an evolutionary scenario suggesting a greater pre‐disposition in women to use language as a relational tool.
Non‐Advertized does not Mean Concealed: Body Odour Changes across the Human Menstrual Cycle
Authors: Havlíček Jan , Dvořáková Radka , Bartoš Luděk , Flegr Jaroslav 
Published: January 2006

AbstractFemales of a number of primate species display their fertile period by behavioural and/or morphological changes. Traditionally, the fertile period in human females has been considered to be concealed. However, this presumption has rarely been tested. One of the possible mechanisms for assessing menstrual cycle phase is through the sense of smell. In this study possible changes in odour across the menstrual cycle were investigated. Samples of body odour were acquired from 12 women (aged 19–27 yr), none of whom were using hormonal contraceptives. Samples were collected using cotton pads worn in the armpit for 24 h, from the menstrual, follicular and luteal cycle phases. Our experimental sample of 42 males (age 19–34 yr) repeatedly rated these odour samples for their intensity, pleasantness, attractiveness and femininity. Raw subjective smell ratings from each man were transformed to z‐scores. Subsequently, these z‐scores were tested by the general linear mixed‐model analysis (PROC MIXED, SAS) with the female's ID nested within the subject's ID as a random factor to account for the repeated measures of the subjects. Significant changes across the cycle were found for ratings of pleasantness [F(2,689) = 702; p = 0.001], attractiveness [F(2,546) = 6.35; p = 0.002] and intensity [F(2,530) = 3.57; p = 0.028]. Odour from women in the follicular (i.e. fertile) phase was rated as the least intense and the most attractive. Subsequent post hoc analysis revealed significant differences in intensity, pleasantness and attractiveness between the menstrual phase and the follicular phase, and in pleasantness and attractiveness between the menstrual and luteal phases. Significant difference between the follicular and the luteal phase was found only for attractiveness. Our results suggest that men can potentially use smell as a mechanism for monitoring menstrual cycle phase in current or prospective sexual partners. Therefore, the fertile period in humans should be considered non‐advertized, rather than concealed.