Biomedical subjects

Kjetil Sundet

Publications and source records attributed to Kjetil Sundet.

At least 19 recordsLinked to original sources

PubMed2006

Age-related psychomotor slowing as an important component of verbal fluency: evidence from healthy individuals and Alzheimer's patients.

Generalized psychomotor slowing is a characteristic of normal aging, and there is evidence suggesting that this feature is also central in dementia. The present article aims to evaluate the importance of psychomotor slowing as a factor underlying changes in the performance of verbal fluency tasks in normal and pathological aging. In study 1 reading and handwriting speed were used to predict performance on written and oral verbal fluency tasks (VFTs) in healthy elderly subjects (n = 20) and in patients of the Alzheimer type disease (n = 20). In study 2, spectrographic techniques were used to obtain reaction times, average of voice intensity and duration of single word production in young individuals (n = 20), healthy elderly subjects (n = 20), and in patients of the Alzheimer type disease (n = 7). Additionally, duration of single word production were also obtained. The results suggest that age-related psychomotor decline in word production speed is an important determinant of VFT.

Aged↗

PubMed2006

Verbal memory performance of mildly to moderately depressed outpatient younger adults.

BACKGROUND: Memory impairment is associated with major depression. Studies on young adults are, however, rare and show inconsistent and contradictory results. The present study investigated the relationship between mild to moderate depression and verbal memory functioning in a relatively large sample of young, non-psychotic, mainly non-medicated outpatients. METHODS: Fifty-seven clinically depressed were compared to 42 previously depressed and 46 never depressed controls on the California Verbal Learning Test. RESULTS: No difference in verbal memory functioning appeared between the three groups, and no difference were obtained between first-episode depressed individuals and individuals with recurrent depression. LIMITATIONS: The study was cross-sectional and prospective studies are needed to confirm our findings. CONCLUSIONS: Our results suggest that relatively young, non-medicated outpatients with mild to moderate depression are not affected by verbal memory impairments.

Adult↗

PubMed2006

Cerebral outcome in adult patients treated with extracorporeal membrane oxygenation.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) carries a high risk of brain injury. The aim of this study was to determine the cerebral status in 28 adult survivors on average 5.0 (range, 0.5 to 12) years after ECMO treatment for severe cardiorespiratory failure. METHODS: All 28 patients were investigated at our institution. A comprehensive assessment protocol included a medical history, physical examination, neuropsychological assessment, electroencephalography, and neuroradiologic assessment. RESULTS: All patients were ambulant unaided, and 43% were without any clinical findings. Impaired neuropsychological performance was found in 41%, neuroradiologic findings in 52%, and a pathologic electroencephalogram in 41% of the patients. There was a significant correlation between the cognitive outcome and neuroradiologic findings. The incidence of neuroradiologic findings (cerebral infarction, microemboli or hemorrhage) was significantly higher in the venoarterial group compared with the venovenous group (75% versus 17%). There was no correlation between the type of ECMO and neuropsychological impairment. Electroencephalography findings did not correlate with neuropsychological performance, nor with the neuroradiologic findings. CONCLUSIONS: Late cerebral sequelae were frequently seen in patients treated on venoarterial ECMO. A significant correlation was found between cognitive impairment and neuroradiologic findings.

Adolescent↗

PubMed2006

Neuropsychological function in a group of patients 25 years after sustaining minor head injuries as children and adolescents.

Previous studies suggest that neuropsychological impairment following mild to moderate pediatric head injury may become persistent and interrupt the normal course of intellectual development. In this study 45 subjects were assessed with a standardized neuropsychological test battery 25 years after sustaining mild to moderate head injury as children. Although the group scores in the normal range, significant relations between head injury severity and current neuropsychological function were found. The most important predictor of poor outcome was length of PTA at injury, EEG pathology, and loss of consciousness at injury. No significant influence of pre- and post-injury risk factors on current neuropsychological function was evident. The findings support the view that complicated mild and moderate paediatric head injury may heighten the risk of developing subtle neuropsychological problems later in life.

Adolescent↗

PubMed2006

Sociodemographic characteristics and cardiovascular risk factors in patients with severe mental disorders compared with the general population.

OBJECTIVE: To study the prevalence and distribution of cardiovascular risk factors in a group of patients with severe mental disorders compared with the general population and investigate if differences in sociodemographic background variables between groups were associated with differences in risk profile. METHOD: We compared data from the ongoing Ulleval 600 Study (205 pharmacologically stable outpatients with DSM-IV psychotic disorders) with data from the 2000-2001 Oslo Health Study (18,770 individuals from the general population of the same area). Subjects were stratified according to age and gender and compared for ethnic background, level of education, marital status, and prevalence of risk factors. RESULTS: Patients had an overall prevalence of smoking, obesity, hypertension, dyslipidemia, and diabetes mellitus about twice that of the reference group. Patients aged 18 through 50 years had the highest level of risk factors when compared with the general population. There was no major difference in ethnic background or educational level between cohorts. CONCLUSION: The increased cardiovascular risk profile in patients is particularly pronounced in young individuals and could not be explained by sociodemographic variables alone.

Adolescent↗

PubMed2005

[Congenital hypothyroidism and the impact of thyroxine treatment].

BACKGROUND: We have studied the significance of the thyroxine treatment for neuropsychological functioning in young adults with congenital hypothyroidism. SUBJECTS AND METHODS: This is a neuropsychological follow-up study of a three-year cohort of early treated congenital hypothyroidism in Norway (N = 49) at age 20. Siblings comprise the control group (N = 41, 21 years). RESULTS: The patient group performed weaker than the control group on cognitive and motor measures. They reported somewhat more psychosocial problems; fewer completed high school. A more severe hypothyroidism at the time of diagnosis was associated with a larger motor deficit at age 20. Better cognitive function in young adulthood was associated with a higher thyroxine starting dose and serum thyroxine level in the first years of life. Blood samples in young adulthood showed elevated thyrotropin levels in 45% of the patients. INTERPRETATION: This study supports the new guidelines for treatment of congenital hypothyroidism with a higher starting dose of 10-15 microg thyroxine/kg/24 hours. The young adults are in need of better medical follow up.

Adolescent↗

PubMed2005

Cerebral ischemic injury and cognitive impairment after off-pump and on-pump coronary artery bypass grafting surgery.

BACKGROUND: Off-pump coronary artery bypass grafting surgery reduces the intraoperative cerebral embolic load and may therefore cause less brain injury. The main aim of this study was to compare off-pump and on-pump surgery with regard to the frequency of new postoperative cerebral ischemic lesions and the prevalence of postoperative cognitive impairment. We also assessed whether preoperative cerebral ischemic injury predicts the risk for cognitive dysfunction after surgery. METHODS: One hundred twenty patients with ischemic coronary artery disease were prospectively randomized to undergo off-pump or on-pump surgery. A detailed neuropsychological assessment and a cerebral magnetic resonance imaging examination were performed on the day before and at 3 months postoperatively. The neuropsychological assessment was repeated at 12 months. RESULTS: There was no significant (p = 0.17) difference between off-pump (8.2%) and on-pump (17.3%) surgery with regard to new postoperative cerebral lesions. The prevalence of cognitive impairment after surgery was also similar in the two groups (3 months: off-pump 20.4%, on-pump 23.1%, p = 0.74; 12 months: off-pump 24.1%, on-pump 23.1%, p = 0.90). The degree of preoperative cerebral ischemic injury was significantly associated with cognitive dysfunction after on-pump (p = 0.02) but not after off-pump (p = 0.22) surgery. None of the patients with normal preoperative radiologic findings were found to have cognitive impairment at 3 months postoperatively (p = 0.04). CONCLUSIONS: Long-term cognitive function and magnetic resonance imaging evidence of brain injury were similar after off-pump and on-pump coronary artery bypass grafting surgery. Preoperative cerebral magnetic resonance imaging can be used to predict the risk for cognitive dysfunction after coronary artery bypass grafting surgery.

Adult↗

PubMed2005

Attention to affective pictures in closed head injury: event-related brain potentials and cardiac responses.

We examined whether closed head injury patients show altered patterns of selective attention to stimulus categories that naturally evoke differential responses in healthy people. Self-reported rating and electrophysiological (event-related potentials [ERPs], heart rate [HR]) responses to affective pictures were studied in patients with mild head injury (n = 20; CT/MRI negative), in patients with predominantly frontal brain lesions (n = 12; CT/MRI confirmed), and in healthy controls (n = 20). Affective valence similarly modulated HR and ERP responses in all groups, but group differences occurred that were independent of picture valence. The attenuation of P3-slow wave amplitudes in the mild head injury group indicates a reduction in the engagement of attentional resources to the task. In contrast, the general enhancement of ERP amplitudes at occipital sites in the group with primarily frontal brain injury may reflect disinhibition of input at sensory receptive areas, possibly due to a deficit in top-down modulation performed by anterior control systems.

Adolescent↗

PubMed2005

Frequency and characteristics of recurrent major depressed patients with unimpaired executive functions.

Major depression is associated with impairment of cognitive functions, and especially higher-order cognitive processes referred to as executive functions (EF). Whether this is a general finding is unclear. Patients without EF impairment may have different treatment needs than patients with EF impairment, and will probably have a better everyday functioning. Thus, it is important to identify the prevalence and characteristics of depressed patients without EF impairment. Forty-three patients with recurrent major depressive disorder (19-51 years) and 50 healthy controls were included in the study. The subjects were assessed with neuropsychological tests selected to measure central areas of EF, and screened on clinical and demographic variables. Within the depressed group, a total of 56% were defined as EF unimpaired. These patients were characterised by higher intellectual abilities and fewer depression episodes than the subgroup of patients with EF impairment. The subgroups were similar in age at debut of illness, severity of depression, general psychopathology and global level of functioning. In conclusion, about half of patients with recurrent major depression have normal EF. Since cognitive impairment and depressive symptomatology seem to be distinct dimensions, a neuropsychological investigation could help to ensure optimal treatment in patients with recurrent major depression.

Adult↗

PubMed2005

Validation of distinct amnesic and executive type memory deficit in a psychiatric sample based on retrieval performance.

Studies of localized brain dysfunctions have revealed connections between patterns of cognitive dysfunction and specific profiles of memory impairment. The amnesic type of memory impairment is defined by deficits in both free recall and recognition memory, whereas the dysexecutive memory impairment is characterized by retrieval deficits, i.e. a disproportional impairment in free recall relative to recognition memory. The present study tests whether classifications of psychiatric patients into recall impaired only (= RO group) and Recall and Recognition impaired (= RR group) correspond to the executive type and amnesic type of memory impairment. The alternative hypothesis is that the two groups merely differ in degree of neuropsychological and psychiatric disturbance. Forty-four subjects impaired on California Verbal Learning Test (CVLT) were selected from a larger database of 103 impaired and non-impaired subjects with schizophrenia or recurrent major depression. Subjects were classified into RO and RR groups and compared on measures of memory strategy (recency effect and interference on CVLT), overall neuropsychological function (Stroop Test and WAIS-R similarity) and psychiatric symptom load (positive and negative symptoms). Repeated measures ANOVA showed no effects of group, i.e. the RR group did not perform consistently below the RO group with regard to memory strategy, neuropsychological function or psychiatric symptom load. Two out of three analyses showed group x test interaction, supporting the dissociation of distinct executive and amnesic profiles among psychiatric patients. The RO group was more susceptible to interference but had better recency score than the RR group. The RO had higher negative symptoms while the RR group had higher positive symptoms.

Amnesia↗

PubMed2004

Early visual information processing in schizophrenia compared to recurrent depression.

Patients with schizophrenia have repeatedly shown deficits in early visual processing using backward masking (VBM) tasks. Whether this represents a specific dysfunction in schizophrenia is an unsolved question. Patients with recurrent unipolar depression represent an interesting comparison group to examine the question of specificity, but have never previously been assessed on VBM. In addition to comparing VBM performance in patients with schizophrenia and patients with depression, we wanted to examine the relations between VBM and clinical symptoms. Fifty-one patients with schizophrenia were compared to 49 patients with recurrent unipolar depression and 47 healthy controls. All subjects were administered a two-digit identification task in a no-masking and four masking conditions. Patients with schizophrenia performed significantly worse than normal controls on four of the five conditions. No significant difference was found between depression patients and normal controls. The effect of masking stimuli had no differential effects on the three groups. VBM correlated strongly with positive symptoms in the schizophrenia group.

Adult↗

PubMed2004

Impairment across executive functions in recurrent major depression.

Depression is associated with impairment of cognitive functions, and especially executive functions (EFs). Despite the fact that most depressed patients experience recurrence of episodes, the pattern and the severity of executive impairment have not been well characterized in this group of depressed patients. We asked if and to what extent these patients were impaired on a range of neuropsychological tests measuring EFs, and also when confounding factors were adjusted for. Forty-five patients (aged 19-51 years) with moderate to severe (Hamilton score >18) recurrent major depressive disorder (DSM-IV) were compared to 50 healthy controls matched on age, education, gender and intellectual abilities. The subjects were administered a set of neuropsychological tests that assesses sub-components of EFs. The depressed patients were impaired compared to the control group on all selected tests, with a severity of impairment within -1 standard deviation from the control group mean. The group difference was statistically significant for eight of the 10 EFs that were assessed. These were measures of verbal fluency, inhibition, working memory, set-maintenance and set-shifting. The group difference was still significant for all sub-components except for set-shifting (Wisconsin Card Sorting Test) and planning (Tower of London), when additional medication and retarded psychomotor speed was adjusted for. In conclusion, the depressed subjects were mildly impaired across a wide range of EFs. This may have a negative impact on everyday functioning for this group of patients.

Adult↗

PubMed2004

Brain activation measured with fMRI during a mental arithmetic task in schizophrenia and major depression.

OBJECTIVE: The authors used functional magnetic resonance imaging (fMRI) to investigate brain activation in patients with schizophrenia and major depression while they performed two tasks-a vigilance task and a mental arithmetic task-that differed in cognitive complexity. METHOD: In the vigilance task, the participants had to press a response button whenever a specific number was seen on a screen inside the MR scanner. In the mental arithmetic task, the participants had to add two consecutive numbers and press the response button whenever the sum was 10. fMRI was performed with a 1.5-T MR scanner. Twelve patients with recurrent nonpsychotic unipolar major depression, 12 patients with schizophrenia, and 12 healthy comparison subjects were included in the study. RESULTS: Performance data showed that the patients were impaired relative to the comparison subjects and showed no difference in performance between the patient groups. The patients with schizophrenia, but not those with major depression, had less activation in prefrontal brain regions, relative to the comparison participants. However, subtracting brain activation during the vigilance task from activation during the mental arithmetic task showed that the schizophrenia patients had activation in parietal areas. CONCLUSIONS: A double dissociation of parietal and frontal lobe activation was found for the schizophrenia patients and the depression patients. The greater parietal lobe activation in the patients with schizophrenia may reflect a compensatory strategy for the failure to recruit cognitive processes that involve frontal lobe areas when solving a mental arithmetic task.

Adult↗

PubMed2003

Attentional and executive dysfunctions in schizophrenia and depression: evidence from dichotic listening performance.

BACKGROUND: We compared performance on a dichotic listening (DL) task between schizophrenic, depressed, and healthy control subjects. A variant of the traditional DL paradigm was used in which the subjects were required to focus attention either on the left (forced-left condition) or right (forced-right condition) ear stimulus. METHODS: The subjects were 51 patients with a DSM-IV diagnosis of schizophrenia, 49 patients with recurrent unipolar major depression, and 49 healthy control subjects. They were tested with a consonant-vowel syllables dichotic listening task under three attentional instructions. RESULTS: There was a significant overall right ear advantage during the nonforced condition, which increased dramatically during the forced-right condition and was eliminated during the forced-left condition. The depressed patients showed no signs of impairments compared with the healthy control group. Thus, they showed a right ear advantage during the nonforced and forced-right conditions, which was shifted to a left ear advantage during the forced left condition. The schizophrenic patients, however, were impaired on the forced-left condition compared with the healthy control and depressed subjects. CONCLUSIONS: The results are discussed in terms of separating attentional and inhibitory executive impairments in schizophrenia and depression, taking into consideration illness duration and information-processing demands.

Attention↗

PubMed2003

Comparison of cerebral embolization during off-pump and on-pump coronary artery bypass surgery.

BACKGROUND: Coronary artery bypass surgery with cardiopulmonary bypass carries a significant risk of perioperative brain injury. At least 1% to 5% will suffer a stroke, and at 3-months postoperatively approximately 30% are reported to have cognitive impairment assessed by neuropsychologic testing. In off-pump surgery cardiopulmonary bypass is not used and instrumentation on the ascending aorta is reduced. The main aim of this study was to assess if off-pump surgery reduces intraoperative cerebral embolization. METHODS: This was a prospective and randomized study of two comparable groups with regard to age, sex, years of education, preoperative cognitive functioning, and surgical characteristics. Fifty-two patients (29 off-pump) were monitored by the use of transcranial Doppler ultrasound for cerebral microembolization during surgery. Preoperative and postoperative clinical, cerebral magnetic resonance imaging, and neuropsychologic examinations were also carried out. RESULTS: There was a significant reduction in the number of cerebral microemboli during off-pump compared with on-pump surgery (16.3 [range 0 to 131] versus 90.0 [range 15 to 274], p < 0.0001). No significant difference with regard to the incidence of neuropsychologic performance (decline in 29% off-pump, 35% on-pump) or neuroradiologic findings at 3 months was found, and there was no association between the number of cerebral microemboli and cognitive outcome. CONCLUSIONS: This study clearly demonstrates that off-pump surgery leads to a reduction in intraoperative cerebral microembolization. A significant reduction in the number of off-pump patients with cognitive decline or ischemic brain lesions on cerebral magnetic resonance imaging could not be demonstrated in this relatively small patient population.

Aged↗

PubMed2003

Sensitivity and specificity of memory dysfunction in schizophrenia: a comparison with major depression.

Fifty-three schizophrenic subjects were compared to 50 patients with major depression and 50 normal controls on measures of working memory, declarative memory and malingering. The schizophrenic group scored 1-2 SDs below controls on all measures, while depressive patients exposed only lesser deficits in working memory and free recall. The memory deficit of the schizophrenic subjects was disproportionately greater than their intellectual decline. Differences between clinical groups could not be explained by differences in IQ, clinical symptom load or demographic characteristics. This indicates that impaired memory is a particular sensitive symptom of schizophrenia and that the impairment is specific to the illness. Working memory failure was prominent in both clinical groups. The schizophrenic subjects displayed primarily an acquisition failure, while the depressed group showed retrieval difficulties.

Adult↗

PubMed2003

Congenital hypothyroidism: influence of disease severity and L-thyroxine treatment on intellectual, motor, and school-associated outcomes in young adults.

OBJECTIVE: To describe intellectual, motor, and school-associated outcome in young adults with early treated congenital hypothyroidism (CH) and to study the association between long-term outcome and CH variables acting at different points in time during early development (CH severity and early L-thyroxine treatment levels [0-6 years]). METHODS: Neuropsychological tests were administered to all 49 subjects with CH identified during the first 3 years of the Norwegian neonatal screening program (1979-1981) at a mean age of 20 years and to 41 sibling control subjects (mean age: 21 years). RESULTS: The CH group attained significantly lower scores than control subjects on intellectual, motor, and school-associated tests (total IQ: 102.4 [standard deviation: 13] vs 111.4 [standard deviation: 13]). Twelve (24%) of the 49 CH subjects had not completed senior high school, in contrast to 6% of the control subjects. CH severity (pretreatment serum thyroxine [T4]) correlated primarily with motor tests, whereas early L-thyroxine treatment levels were related to verbal IQ and school-associated tests. In multiple regression analysis, initial L-thyroxine dose (beta = 0.32) and mean serum T4 level during the second year (beta = 0.48) predicted Verbal IQ, whereas mean serum T4 level during the second year (beta = 0.44) predicted Arithmetic. CONCLUSIONS: Long-term outcome revealed enduring cognitive and motor deficits in young adults with CH relative to control subjects. Verbal functions and Arithmetic were associated with L-thyroxine treatment variables, suggesting that more optimal treatment might be possible. Motor outcome was associated with CH severity, indicating a prenatal effect.

Adult↗

PubMed2002

[Whiplash injuries--a psychosomatic perspective].

BACKGROUND: Psychosocial impairment after whiplash injury could be extensive; presumably about 15% of whiplash patients suffer from long lasting disabling health problems and about 5% do not return to work. MATERIAL AND METHODS: A PubMed search of all available literature on whiplash and whiplash-associated disorders was performed. RESULTS: Psychosocial impairment following whiplash injury is influenced by vulnerability factors, the biomechanical trauma and factors affecting symptom formation. Vulnerability factors indicating a poorer prognosis include low mental abilities, previous mental illness, old age and female sex, pre-existing cervical degenerative changes, narrow spinal canal and high neurobiological reactivity to sustained activation. The actual physical trauma consists of a nonphysiologic kinematic response in the cervical column, which may induce stress in neural structures, facet joints and musculature. Activation of reflex connections may lead to disturbances in the posture control and autonomic system. Trauma-related prognostic factors include head position at impact and degree of acute psychological stress reactions. Manual work, expectation of disability and an ongoing compensation claim case seem to be important moderator variables affecting symptom formation. INTERPRETATION: An integrated psychosomatic model is needed to explain psychosocial impairment after whiplash injury as presented.

Accidents, Traffic↗