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S Arndt

Publications and source records attributed to S Arndt.

At least 37 records · Page 2Linked to original sources
PubMed2001

Bioavailable testosterone as a correlate of cognition, psychological status, quality of life, and sexual function in aging males: implications for testosterone replacement therapy.

Andropause is a syndrome described in aging males, is composed of a constellation of physical, sexual, and emotional symptoms, and is thought to be related to declining concentrations of serum testosterone. Numerous studies of testosterone replacement therapy in elderly hypogonadal males have documented the physical benefits of such treatment, but have failed to assess cognition, psychological functioning, and quality of life. Male outpatients greater or equal to 55 years of age completed cognitive, psychological, sexual, and quality of life assessments. A serum sample was provided for bioavailable testosterone assay. The associations between bioavailable testosterone concentrations and neuropsychological testing were assessed using Spearman rank correlation. Overall, bioavailable testosterone was not an important determinant of cognitive, psychological, or sexual functioning or of quality of life. The implications for future studies involving testosterone replacement therapy are discussed.

Aged↗
PubMed2001

Lithium and suicidal behavior in major affective disorder: a case-control study.

OBJECTIVE: A number of studies have suggested that lithium may be particularly effective in reducing suicide risks among patients with major affective disorders. The design of many of these studies left them open to biases associated with treatment compliance, however. METHOD: Subjects were drawn from a naturalistic, long-term follow-up of patients with major affective disorders. Fifteen who committed suicide while receiving somatotherapy where matched to non-suicidal patients who were similarly receiving somatotherapy at the same point in follow-up. The same procedure was followed for 41 patients who made a serious suicide attempt during follow-up. RESULTS: Six (40.0%) of the patients who committed suicide, and eight (53.3%) of their controls, were thought to have been taking lithium in the preceding week. Among attempters and their controls, nine (22.0%) and eight (19.5%), respectively, were taking lithium. CONCLUSION: These results do not support previous suggestions that lithium has uniquely antisuicidal properties. Other existing datasets should be explored with this design to establish whether lithium does, or does not, offer special protection against suicide.

Adult↗
PubMed2001

The effect of remission of poststroke depression on activities of daily living in a double-blind randomized treatment study.

Poststroke depression has been associated with impaired recovery of activities of daily living (ADL) during the first 2 years after stroke. This study examined the effect of remission of poststroke depression on recovery in ADL in a double-blind randomized treatment study. Based on a semistructured psychiatric exam and DSM-IV diagnostic criteria, a consecutive series of 23 patients who met criteria for major depression (N = 16) or minor depression (N = 7) were selected and randomly assigned to either active treatment (nortriptyline) or placebo. Functional physical (i.e., ADL) impairment was assessed using the Johns Hopkins Functioning Inventory (JHFI). Patients whose depressive disorder remitted at follow-up had significantly greater recovery in ADL functions compared with patients whose depression did not remit. There were no differences in demographic variables, lesion characteristics, and neurological symptoms between the two groups, which would explain the significantly greater improvement among the remitted patients. Because both major and minor depression patients who remitted showed greater improvement in ADL than nonremitted patients some of whom were treated with active and some with placebo medication, nonpharmacotherapeutic mechanisms related to recovery from depression appear to mediate this enhanced recovery.

Activities of Daily Living↗
PubMed2000

The impact of substance abuse on the course of bipolar disorder.

BACKGROUND: Substance abuse occurs at high rates in bipolar disorder. The reasons for this co-occurrence are unknown. Alcohol use disorders have been associated with both earlier and later age of onset of bipolar disorder, in part based on the temporal associations of the two conditions. Both drug and alcohol use disorders are associated with impaired outcome of bipolar illness. This influence may involve both direct effects of alcohol or drugs on the initiation of affective symptoms and indirect effects on treatment compliance. To extend these previous findings we examined the temporal associations of substance abuse and affective symptoms in patients with new onset bipolar disorder. METHODS: Associations between affective symptoms and alcohol and cannabis use disorder symptoms were evaluated using regression and time-series correlative methods in 50 new-onset bipolar patients. RESULTS: The duration of alcohol abuse during follow-up was associated with the time patients experienced depression. The duration of cannabis abuse was associated with the duration of mania. Several subgroups could be identified with different temporal relationships among these disorders. CONCLUSIONS: Although the relationships among substance use and bipolar disorders are complex, systematic study of the courses of the disorders might clarify how these conditions interact longitudinally. As the numbers of subjects in specific subgroups are relatively small in this study, these results should be considered preliminary.

Acute Disease↗
PubMed2000

Cerebellar hypoactivity in frequent marijuana users.

It is uncertain whether frequent marijuana use adversely affects human brain function. Using PET, regional cerebral blood flow was compared in frequent marijuana users and comparable, non-using controls after at least 26 h of monitored abstention by all subjects. Marijuana users showed substantially lower brain blood flow than controls in a large region of posterior cerebellum, indicating altered brain function in frequent marijuana users. A cerebellar locus of some chronic and acute effects of marijuana is plausible, e.g. the cerebellum has been linked to an internal timing system, and alterations of time sense are common following marijuana smoking.

Adult↗
PubMed2000

Effects of frequent marijuana use on brain tissue volume and composition.

To investigate CNS effects of frequent marijuana use, brain tissue volume and composition were measured using magnetic resonance imaging (MRI) in 18 current, frequent, young adult marijuana users and 13 comparable, non-using controls. Automated image analysis techniques were used to measure global and regional brain volumes, including, for most regions, separate measures of gray and white matter. The marijuana users showed no evidence of cerebral atrophy or global or regional changes in tissue volumes. Volumes of ventricular CSF were not higher in marijuana users than controls, but were, in fact, lower. There were no clinically significant abnormalities in any subject's MRI. Sex differences were detected in several global volume measures.

Adult↗
PubMed2000

Personality change disorder in children and adolescents following traumatic brain injury.

The occurrence of personality change due to traumatic brain injury (PC), and its clinical and neuroimaging correlates were investigated. Ninety-four children, ages 5 through 14 at the time of hospitalization following traumatic brain injury (TBI; severe TBI N = 37; mild-moderate TBI N = 57), were assessed. Standardized psychiatric, adaptive functioning, cognitive functioning, family functioning, family psychiatric history, severity of injury, and neuroimaging assessments were conducted. The Neuropsychiatric Rating Schedule (NPRS) was used to establish a diagnosis of PC. Approximately 40% of consecutively hospitalized severe TBI participants had ongoing persistent PC an average of 2 years postinjury. An additional approximately 20% had a history of a remitted and more transient PC. PC occurred in 5% of mild-moderate TBI but was always transient. Interrater reliability for the diagnosis of PC was good (Kappa = .70). In severe TBI participants, persistent PC was significantly associated with severity of injury, particularly impaired consciousness over 100 hr, adaptive and intellectual functioning decrements, and concurrent diagnosis of secondary attention deficit hyperactivity disorder, but was not significantly related to any psychosocial adversity variables. These findings suggest that PC is a frequent diagnosis following severe TBI in children and adolescents, but is much less common following mild-moderate TBI.

Brain Injury, Chronic↗
PubMed2000

Association between cytochrome P4502D6 (CYP2D6) genotype, antipsychotic exposure, and abnormal involuntary movement scale (AIMS) score.

Antipsychotic metabolism cosegregates with the polymorphic cytochrome P4502D6 (CYP2D6) hepatic enzyme. Approximately 5-10% of Caucasians show impaired metabolism associated with nonfunctional alleles. Genotyping determines the number of functional alleles, which is phenotypically not possible. The aim of this study was to investigate associations between CYP2D6 genotype, antipsychotic exposure, and abnormal involuntary movement scale (AIMS) score. Schizophrenic patients (DSM-IV) were genotyped for CYP2D6*1, *3, and *4 alleles by nested polymerase chain reaction. A complete history, including psychiatric symptoms, medications and AIMS score was obtained. Antipsychotic exposure was recorded in dose years [(chlorpromazine equivalents x years)/100]. A linear regression model used AIMS scores as the dependent variable. Genotype, gender, antipsychotic exposure, and interactions were independent variables. The results of the 31 patients studied showed: 20 were homozygous for the *1 allele (*1/*1) and 11 were heterozygous for the *1 allele (i.e. *1/*3 or *4). Age, sex, age of onset, treatment duration, antipsychotic exposure, and AIMS scores did not differ between groups. The interaction between dose years and genotype was significant (P < 0.0055), demonstrating that for (*1/*1) patients, the magnitude of antipsychotic exposure had a greater effect on AIMS score (slope = 0.044) compared with (*1/*3 or *4) patients (slope = 0.001). These results suggest patients with a *3 or *4 allele may have a higher risk for developing antipsychotic induced abnormal movements.

Age of Onset↗
PubMed2000

Memory complaint in a community sample aged 70 and older.

OBJECTIVES: The ability of older people to estimate their own memory, often referred to as "metamemory," has been evaluated in previous studies with conflicting reports regarding accuracy. Some studies have suggested that an older person's metamemory is mostly accurate, whereas others have demonstrated little relationship between memory complaint and actual impairment. This study examines memory complaint in a large national sample of older people aged > or = 70. DESIGN: A longitudinal cohort study with two waves of data collection spaced 2 years apart. SETTING: A nationwide random sample of community-dwelling older persons. PARTICIPANTS: A total of 5,444 community-dwelling persons aged > or = 70 and their spouses. MEASUREMENTS: Participants were asked if they believed their memory was excellent, very good, good, fair, or poor. They were then administered a cognitive assessment derived from the Mini-Mental Status Exam. RESULTS: In general, people's assessment of their memory corresponded with their actual performance on cognitive measures. However, large portions of the sample inaccurately assessed their memory skills. People who reported depressive symptoms and had impairment in activities of daily living were more likely to state that their memory was impaired, although they performed very well on cognitive measures. CONCLUSIONS: The conditions that skew people's self-assessment are the ones most likely to bring them into contact with healthcare professionals. This may give clinicians the general impression that older people cannot assess their own cognitive skills. However, poor metamemory appears to be a characteristic of a specific subgroup of older persons, not necessarily characteristic of the general population.

Activities of Daily Living↗
PubMed2000

Cognitive correlates of the negative, disorganized, and psychotic symptom dimensions of schizophrenia.

Knowledge of the relationship between specific cognitive abnormalities and the clinical symptoms of schizophrenia could give insight into the nature of their underlying pathophysiology. Composite scores were generated for negative, disorganized, and psychotic symptom ratings in 134 patients with schizophrenia (DSM-IV criteria). Partial correlations (each composite corrected for the others) were computed with neuropsychological measures. Negative symptoms were related to poor performance on tests of verbal learning and memory, verbal fluency, visual memory, and visual-motor sequencing. Disorganized symptoms were correlated with lower verbal IQ and poor concept attainment. Psychotic symptoms had no significant relationship with cognitive deficit.

Adult↗
PubMed1999

Caudate size in first-episode neuroleptic-naive schizophrenic patients measured using an artificial neural network.

BACKGROUND: Structural brain imaging studies have demonstrated an increase in caudate volume in schizophrenic patients medicated with typical neuroleptics and a volume decrease following treatment with atypical neuroleptics. The measurement of striatal volume in patients who have never been treated with neuroleptics may indicate whether these changes are superimposed on intrinsic basal ganglia pathology in schizophrenia or are solely neuroleptic-induced. METHODS: We studied 36 first-episode, neuroleptic-naive schizophrenic patients and 43 control subjects using an artificial neural network (ANN) to identify and measure the caudate nucleus. The resulting volumes were analyzed using an ANCOVA controlling for intracranial volume, age, gender, and socioeconomic status. RESULTS: The mean volume difference between the caudate nuclei of patients and control subjects was .297 mL, the caudate nuclei of the patients being smaller than those of controls. When we covaried for intracranial volume, this was a statistically significant difference in caudate volume (n = 79; df = 1,75; F = 4.18; p > .04). CONCLUSIONS: Caudate nuclei of neuroleptic naive schizophrenic patients are significantly smaller than those of controls. This suggests that patients suffering from schizophrenia may have intrinsic pathology of the caudate nucleus, in addition to the pathology observed as a consequence of chronic neuroleptic treatment.

Adult↗
PubMed1999

Cluster headaches: association with anxiety disorders and memory deficits.

OBJECTIVE: To estimate the frequency of mood and anxiety disorders and to assess memory and executive functions among a representative group of patients with episodic cluster headache (ECH) during the course of an acute episode. METHODS: We compared 21 patients with ECH with 21 patients with tension headache (TH) matched for age, sex, and educational level. Psychiatric diagnosis was made by a semi-structured interview and Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM-IV) criteria. Quantitative measures of depression and anxiety were obtained using the Hamilton Depression Rating Scale and the Hamilton Anxiety Rating Scale (HARS). In addition, all patients received a neuropsychological evaluation to assess basic memory and executive functions. RESULTS: Of the 21 patients with ECH, 5 (24%) met DSM-IV criteria for an anxiety disorder during the year before the episode. Panic disorder was diagnosed in two patients (10%). The remaining three patients (14%) met criteria for generalized anxiety disorder. Of the 21 patients with TH, 2 (10%) met diagnostic criteria for an adjustment disorder with depressed mood, and 1 (5%) met criteria for an adjustment disorder with mixed anxiety and depressed mood. HARS scores were higher among patients with ECH (Kruskal-Wallis, chi2 = 4.3, df = 1, p = 0.03). ECH patients also showed significantly lower Auditory Verbal Learning Test scores (Kruskal-Wallis, chi2 = 6.5, df = 1, p = 0.01). CONCLUSIONS: When compared with a group of patients with TH, ECH patients showed a higher frequency of anxiety disorders during the year before the onset of headaches and significantly greater HARS scores during the episode. In addition, patients with ECH were selectively impaired in verbal memory.

Adult↗
PubMed1999

The 35% CO2 inhalation procedure: test-retest reliability.

The subjective response to a single-breath, 35% carbon dioxide challenge test shows promise as a tool for the study of panic disorder and may comprise a trait marker for that disorder. Little has been done to measure the reliability of test results, however. Subjects took a single breath at 35% CO2 and completed a self-rating of anxiety symptoms immediately thereafter. This procedure was repeated after a mean interval of 29 days. One group, considered at high risk for panic disorder, consisted of well, first-degree relatives of individuals treated for panic disorder. The control group included well subjects at high risk for affective disorder and subjects who had family histories negative for both affective disorder and panic disorder. On both testing occasions, subjects at high risk for panic disorder had symptom scores that were significantly higher than those of control subjects. Group differences in the portions who experienced a panic attack were dependent on the symptom threshold used to define an attack. A lower threshold was optimal with the second testing and a single, positive test result appeared to be more meaningful than a single negative result. The majority of individual symptom ratings were highly correlated across tests. Ratings for "smothering sensations," in particular, correlated highly across tests and consistently discriminated high-risk from control subjects. The sources of test result variability are unclear and warrant more investigation before the tests can be clinically useful. Research efforts should seek optimal thresholds to define positive test results within given data sets.

Administration, Inhalation↗
PubMed1999

Generalized cognitive deficits in schizophrenia: a study of first-episode patients.

BACKGROUND: Cognitive impairment is recognized as a core characteristic of schizophrenia. There has always been a debate about the nature, selectivity, and time of onset of these deficits in relationship to the onset of illness and treatment factors. To our knowledge, the present study represents the largest sample of mostly neuroleptic-naive patients with first-episode schizophrenia that has been reported to date. METHODS: A group of 94 patients experiencing their first episode of schizophrenic illness and 305 normal comparison subjects were administered a comprehensive clinical and neuropsychological evaluation. Seventy-three patients were neuroleptic naive, 14 had received treatment for less than 1 week, and the remaining 7 had been medicated for less than 2 weeks. RESULTS: Patients performed significantly worse than the comparison subjects on every neuropsychological variable except those assessing savings scores (ie, forgetting over time). Twenty-five of 30 tests had an effect size (ES) greater than 0.75 when the 2 groups were compared. An ES analysis within the schizophrenia group revealed that the greatest relative impairments were on the Wechsler Adult Intelligence Scale-Revised digit symbol (ES, -0.52) and comprehension (ES, -0.42) subscales. CONCLUSIONS: Our findings are in concert with others demonstrating that significant cognitive impairment across multiple ability domains is a core characteristic of schizophrenia and is not caused by chronic illness, treatment, or institutionalization. The ES analysis emphasizes that patients with schizophrenia have a generalized deficit that is not easily explained by a single anatomical region or ability area.

Adult↗
PubMed1999

Intra- and inter-individual correlations between cholecystokinin and corticotropin-releasing hormone concentrations in human cerebrospinal fluid.

Despite strong evidence of a physiologic relationship between cholecystokinin (CCK) and corticotropin-releasing hormone (CRH) in the rat central nervous system (CNS), evidence of such a relationship between the two hormones in the human CNS is lacking. A post hoc analysis of serial concentrations of immunoreactive CCK and CRH, obtained every ten minutes from CSF continuously collected over six hours, was performed. A total of 30 subjects were studied: 15 normal volunteers, 10 patients with major depression, and 5 recently-abstinent, alcohol-dependent patients. Overall, we observed an average intra-subject correlation of +.273 (P < 0.001) between CSF CRH and CCK. Inter-subject correlations between mean CSF levels of CRH and CCK were +.948 (P = 0.0001) and +.959 (P = 0.005) in the depressed and abstinent alcoholic patients, respectively. These inter-individual correlations were significantly greater than that seen within the group of normal volunteers (r = +.318, n.s.). The present data suggest that interactions between CCK and CRH are significant in the human CNS, particularly perhaps in depressed and alcoholic patients, and that CSF samples may be used to assess elements of the relationship between these hormones.

Adult↗
PubMed1999

[Internal knee injuries in children].

Although children are injured everyday through accidents, road traffic, leisure or sports activities, internal lesions of the knee joint due to the trauma are rare. Diagnose and therapy follow rather empirical than analytical patterns. A retrospective, controlled study evaluates and recommends ways of treatment. Traumatic internal lesions of the knee where analysed in 76 children up to age 16. The pattern of injury changed with increasing age, the trauma remaining the same. Most common where injuries to the anterior cruciate ligament (ACL). Main cause where sports activities. Operative treatment seems to be the appropriate treatment. Osseous avulsions of the cruciates and collateral ligaments showed good results after transosseous refixation with a suture. Suturing of intraligamentous ACL-ruptures as well as patellar ligaments plasty showed unsatisfactory results. Secondary lesions due to instability of the knee where also observed in children. Children cannot self estimate the severity of the injury so subjective statements are insecure. Trauma, surgery, pain and immobilisation cause a marked malfunction of the sensor-motor system which is effectively treated by physiotherapy.

Adolescent↗
PubMed1999

Maternal plasma homocysteine, placenta status and docosahexaenoic acid concentration in erythrocyte phospholipids of the newborn.

UNLABELLED: The enhanced transport of long-chain polyunsaturated fatty acids, in particular docosahexaenoic acid (22:6 omega-3) (DHA), to the fetus is a placental function important for adequate membrane phospholipid formation and herewith decisive for the quality of fetal CNS myelination. A compromised placental function is correlated with signs of vascular pathology. As elevated plasma total homocysteine (tHcy) concentrations are considered an independent risk for premature occlusive vascular disease, the influence of maternal plasma tHcy concentrations on placental function was indirectly studied, determining the DHA content in erythrocyte membrane phospholipids of the newborn. A total of 60 unselected pregnant women (age range: 21 to 39 years) were investigated at delivery. Gestational age ranged from 26 to 41 weeks. Prior to delivery a placental ultrasound scan was performed. Complete sets of data could be obtained from 43 mothers and their offspring. tHcy concentrations were determined in the plasma of cord and maternal blood. The fatty acid pattern of erythrocyte membrane phospholipids was determined in the mothers and their newborns. Z-scores of the birth weights ranged from -3.4 to 2.1 and of the placental weights from -3.8 to 4.7. The mean maternal plasma tHcy concentration was 6.29 +/- 3.34 micromol/l ranging from below our limit of detection up to 15 micromol/l. These maternal concentrations were correlated with those of their infants (r = 0.71; P < 0.0001). The tHcy concentrations were significantly higher in mothers with pregnancies complicated by gestosis or placental calcifications. The Z-scores of birth weights as well as placental weights showed a significant negative correlation with maternal plasma tHcy concentrations. The mean DHA percentage of total fatty acids in erythrocyte phospholipids was 3.2 +/- 2.2% in the mothers and 3.4 +/- 2.3% in their newborns. Most importantly the maternal plasma tHcy levels and the erythrocyte phospholipid DHA concentrations of their offspring were significantly correlated (r = -0.51; P < 0.0003). CONCLUSION: In this study, total homocysteine concentrations were elevated in the plasma of pregnant women with signs of placental vasculopathy. Maternal plasma total homocysteine concentrations were positively correlated with erythrocyte phospholipid docosahexaenoic acid of their offspring and may be an indicator for the integrity of placental vascular function. The nutritional status as well as predisposing genetic factors of pregnant mothers need to be investigated more thoroughly.

Adult↗