Biomedical subjects

Erik Lykke Mortensen

Publications and source records attributed to Erik Lykke Mortensen.

At least 19 recordsLinked to original sources

PubMed2007

Memory deficits in long-term survivors of childhood brain tumors may primarily reflect general cognitive dysfunctions.

BACKGROUND: To analyze the impact of potential predictors on memory performance in survivors of childhood brain tumors and to examine whether deficits in memory after radiotherapy (RT) should be considered part of a more global mental dysfunction. PROCEDURE: We studied 126 patients with brain tumors diagnosed before the age of 15 years and treated January 1970 through February 1997 in Eastern Denmark. Sixty-nine of the 126 patients had received RT. In addition to working memory and long-term memory (LTM), general intelligence (IQ) was assessed. RESULTS: The mean test scores in nearly all memory tests were lower than expected from available norms. In multiple linear regression, treatment with RT, hemisphere tumor location, and hydrocephalus treated with a shunt at the time of diagnosis were found to be significant risk factors for memory deficits. When IQ was included as a covariate, RT did not significantly predict memory performance, while shunt and tumor location remained significant for several but not all tests. CONCLUSION: These results suggest that in patients treated with RT, memory deficits primarily reflect a general cognitive dysfunction, and it is likely that these intelligence deficits may compromise the chances of success of special memory training. In contrast, memory deficits in non-irradiated patients may to some degree reflect specific cognitive dysfunctions being most pronounced for patients treated with a shunt and for patients with hemispheric tumors.

Adolescent↗

PubMed2007

Response times of children and adolescents with Asperger syndrome on an 'advanced' test of theory of mind.

In the present study the response times of 10- to 20-year-old participants with Asperger syndrome (AS) (N=21) of normal intelligence and a control group of typically developing individuals (N=20) were recorded on a new 'advanced' test of theory of mind. This test taps the ability to make mental-state inferences versus physical-state inferences in a story context. The participants with AS were significantly slower than the controls on both tasks. In addition, the differences in response times between mental- and physical-state inference were significantly larger in the AS group than in the control group, suggesting that the clinical group experienced more problems than the controls in making inferences about mental states than about physical states.

Adolescent↗

PubMed2007

Disembedding performance in children and adolescents with Asperger syndrome or high-functioning autism.

The aim of the present study was to assess the findings, reported in earlier studies, that individuals with autism spectrum disorders process visuo-spatial tasks faster than typically developing control persons. The participants in the present study were children and adolescents with Asperger syndrome (AS) or high-functioning autism (HFA) (N = 13), and a matched group of typically developing children and adolescents (N = 13). The results showed that the participants in the clinical group performed marginally less well than those in the control group on both the Block Design Test and the Embedded Figures Test, but the differences were not statistically significant. Thus, earlier findings suggesting that individuals with autism spectrum disorders solve non-social cognitive tasks faster than typically developing control persons were not replicated. The results are discussed with special reference to the hypothesis of weak central coherence.

Adolescent↗

PubMed2006

Psychometric properties of brief indexes designed to measure social-cognitive predictors of smoking initiation.

BACKGROUND: Constructing indexes which measure factors that may predict smoking initiation is essential for planning prevention programs. Our aim was to examine the criterion-related construct validity of brief psychological indexes of attitude, social influence and self-efficacy to be used in future studies for predicting smoking initiation in adolescents. METHODS: Five indexes were evaluated using cross-sectional data on 4819 adolescents age 13 in a random sample of schools in six Danish counties. Item analyses were performed with the graphical log-linear Rasch model, a modification of the Rasch model that allows for differential item functioning and positive local dependence. RESULTS: The three indexes social influence-norms, social influence-pressure and attitude showed acceptable deviations from the Rasch model, while the two indexes self-efficacy and social influence-behavior were invalidated by negative local dependence. CONCLUSION: Of the five tested indexes, three (social influence-norms, social influence-pressure and attitude) showed acceptable criterion-related construct validity and may be considered unbiased representations of the theory-based factors if statistical analyses are appropriately adjusted. The results of this population-based study show that the graphical log-linear Rasch model is useful for evaluating health-related behavior indexes and identifying problems, which can be dealt with when using the indexes in future studies.

Adolescent↗

PubMed2006

Patient versus informant reported quality of life in the earliest phases of Alzheimer's disease.

OBJECTIVES: The study investigated if patient and informant reported Quality of Life (QoL) differed in early Alzheimer's disease (AD). In addition, we examined whether anosognosia had an impact on the agreement between patient and informant ratings of QoL and whether anosognosia, dementia severity, depression and behavioural symptoms were significantly correlated to QoL in early AD. METHODS: From a prospective research program including newly referred patients (age >60 years and MMSE > or = 20), 48 patients with very early AD were included. QoL was assessed using the QoL-AD and EQ-5D scales. Anosognosia was rated on a categorical scale by an examiner. MMSE, Geriatric Depression Scale, Danish Adult Reading Test and Frontal Behavioural Inventory were also administered. RESULTS: On most QoL measures patients rated their QoL higher than their informants. Anosognosia was not associated with QoL but significantly with an inverse impact on the agreement between patient and informant ratings of QoL. Self-reported QoL was significantly correlated to depression but not to age, dementia severity, behavioural symptoms or memory impairment. Informant ratings of QoL were significantly correlated to behavioural symptoms and informant ratings on the EQ-5D Visual Analogue Scale were significantly correlated to patient reported depression. CONCLUSION: Patients with early AD generally reported higher QoL than their informants. This disagreement was associated with the presence of anosognosia. Self-reported QoL did not correlate with the MMSE score. Behavioural changes and depressive symptoms may be associated with low QoL.

Aged↗

PubMed2006

Mental vulnerability--a risk factor for ischemic heart disease.

OBJECTIVE: The purpose of this study is to examine whether mental vulnerability is a risk factor for the development of ischemic heart disease (IHD) after adjustment for well-established risk factors. METHODS: In three prospective cohort studies in Copenhagen County, Denmark, we recorded the level of mental vulnerability and possible risk factors to IHD at baseline. For follow-up, the sample was linked to relevant registries to identify all cases of fatal and nonfatal IHD. The relationship between mental vulnerability and IHD was examined using both Kaplan-Meir and Cox proportional hazard models adjusting for possible confounding factors. RESULTS: Mental vulnerability was significantly associated with the risk for IHD (medium mental vulnerability: hazard ratio 1.41, 95% confidence interval 1.04-1.91; and high mental vulnerability: hazard ratio 2.05; 95% confidence interval 1.46-2.88), after adjusting for confounders. CONCLUSION: Our results imply that mental vulnerability is an independent risk factor for IHD.

Adult↗

PubMed2006

Premorbid personality in schizophrenia spectrum: a prospective study.

Schizophrenia has been linked with premorbid character anomalies since it was first described. However, few prospective studies of premorbid personality characteristics in schizophrenia and related disorders have been conducted. This study evaluates premorbid personality in children who developed schizophrenia spectrum disorder in adult life. In 1972, 265 children at an average age of 12 (90 with at least one schizophrenic parent) from the Copenhagen Perinatal Cohort participated in a 1-day follow-up during which they were in contact with seven examiners who rated their personality by means of an Adjective Check List (ACL). In 1991-93, adult psychiatric status was assessed for 242 of these individuals, who were classified into three categories: schizophrenia spectrum (n=24), other psychiatric diagnoses (n=72) and healthy controls (n=145). Personality characteristics derived from the ACL were linked to these three diagnostic categories. Twelve-year-old children destined to develop a disorder in the schizophrenia spectrum deviated significantly from healthy controls on a number of personality characteristics: they were rated significantly lower than controls on intelligence, concentration, maturity, friendliness, cooperation, self-control and significantly higher on aggression. Non-significant trends indicated that this group displayed more deviant personality scores than psychiatric controls. Children who later develop schizophrenia spectrum disorder differed from normal controls with respect to a number of personality traits. The ACL may be too insensitive to discriminate between premorbid personality in the schizophrenia spectrum and other psychopathology.

Adolescent↗

PubMed2006

Intellectual development in a Danish cohort of prematurely born preschool children: specific or general difficulties?

A national cohort of extremely low birth weight (ELBW) and/or extremely preterm (EPT) children and a term control group was followed up at the age of 5 years. The primary objective was to investigate whether premature birth had a global impact on cognitive functions or affected specific functions only. Assessment tools were Wechsler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R), Movement Assessment Battery for Children (M-ABC), and subtests from the Neuropsychological Assessment 4-7 years (NEPSY). The mean Full Scale IQ (FSIQ) and M-ABC score of the index children were 1.1 and 1.2 SDs lower than that of the control children (p <.001). Most WPPSI-R subtests showed medium to large differences between index and control children, suggesting a global impact of premature birth on cognitive functions. For both unadjusted and FSIQ adjusted means, no significant group differences on tests of memory or executive function were observed (p >.1), suggesting little impact of premature birth on these specific functions. In this sample, cognitive difficulties in 5-year-old ELBW and/or EPT children tended to be associated with general intellectual difficulties rather than with specific dysfunctions; however, the implications of this finding are ambiguous due to substantial attrition on the NEPSY subtests.

Child, Preschool↗

PubMed2006

Mental health and health-related quality of life: a 10-year follow-up of tortured refugees.

The aim of the study was to identify predictors of mental symptoms (posttraumatic stress disorder, depression, and anxiety), and of health-related quality of life in refugees 10 years after referral to the Rehabilitation and Research Centre for Torture Victims, and to study changes in mental health over time. The study sample comprises 139 tortured refugees admitted to a pretreatment assessment in 1991 to 1994. Data on background and trauma, and in a subsample on mental symptoms, were collected at baseline. In 2002 and 2003, data on mental symptoms, health-related quality of life, and the participants' social situation were collected. The level of emotional distress was high at follow-up. Social relations and unemployment at follow-up were important predictors of mental health symptoms and low health-related quality of life. A significant decrease in mental symptoms was observed in the subsample. Social relations and unemployment should be taken into account when developing health-related and social interventions.

Adult↗

PubMed2006

Associations between volume of alcohol consumption and social status, intelligence, and personality in a sample of young adult Danes.

Relatively few studies have investigated associations between volume of alcohol consumption and psychological characteristics in normal samples. A sub-sample, comprising 363 men and 331 women between 29 and 34 years of age, was selected from the Copenhagen Perinatal Cohort on the basis of perinatal records. The sample was divided into four consumption categories: abstainers (including occasional drinkers), light, moderate, and risk drinkers. ANOVA and relevant contrasts were used to test the significance of differences among consumption categories. Both abstaining and risk drinking were associated with low social status family background, low education and intelligence. Abstaining was associated with low disinhibition and social recognition scores, while risk drinking was associated with high neuroticism and, in males, high disinhibition, low social recognition, and low achievement scores. Compared with light drinkers, a more "carefree" life orientation characterized male moderate drinkers, while relatively high scores on anxiety, dysthymia, and somatoform symptom scales characterized female moderate drinkers.

Adult↗

PubMed2005

The Strange Stories test--a replication study of children and adolescents with Asperger syndrome.

The aim of the present study was to assess the ability of 21 children and adolescents with Asperger syndrome (AS) of normal intelligence to infer mental states in a story context using Happe's Strange Stories test. The participants in the AS group were compared with an age-matched control group (N=20) of normally developing children and adolescents on a test of social understanding. The test material comprised social communication such as Pretence, Joke, Lie, White Lie, Figure of Speech, Misunderstanding, Persuasion, Irony, Double Bluff and Contrary Emotions, Appearance/Reality and Forgetting. As compared to the controls, the participants in the AS group performed less well on these tasks, and answered fewer correct mental state inferences, but performed well on a physical state control task. This study supports the main finding of earlier studies, showing that even individuals with AS of normal intelligence have problems in using mental state terms context-appropriately when tested on the Strange Stories test.

Adolescent↗

PubMed2005

Mental vulnerability as a predictor of early mortality.

BACKGROUND: Studies have demonstrated that mental vulnerability (ie, a tendency to experience psychosomatic symptoms or inadequate interpersonal interactions) is associated with various diseases. The objective of our study is to evaluate whether mental vulnerability is a risk factor for early mortality. METHODS: We conducted a prospective cohort study of 3 random samples of the population in Copenhagen County, Denmark selected in 1976, 1982-1984, and 1991 (n = 6435). Baseline data collection included measures of mental vulnerability, social factors, comorbidity, biologic risk markers (eg, blood pressure, lipid levels), and lifestyle factors. We determined vital status of the study sample through linkage to the Civil Registration System until 2001 and to the Cause of Death Registry until 1998. The mean follow-up time was 15.9 years for analysis of total mortality and 13.6 years for analysis of mortality as the result of natural causes. The association between mental vulnerability and survival was examined using Kaplan-Meir plots and Cox proportional-hazard models adjusting for possible confounding factors. RESULTS: With respect to mental vulnerability, 79% of the sample was classified as not vulnerable, 13% as moderately vulnerable, and 8% as highly vulnerable. Compared with the nonvulnerable group, highly vulnerable persons showed increased total mortality (hazard ratio = 1.6; 95% confidence interval = 1.3-1.9) and increased mortality from natural causes (1.6; 1.2-2.0). The inclusion of the mental vulnerability score as a continuous variable gave similar results. CONCLUSIONS: Mental vulnerability may be an independent risk factor for premature mortality. The biologic mechanisms that may underlie this association need further exploration.

Adult↗

PubMed2005

A follow-up study of mental health and health-related quality of life in tortured refugees in multidisciplinary treatment.

Longitudinal studies of traumatized refugees are needed to study changes in mental health over time and to improve health-related and social interventions. The aim of this study was to examine changes in symptoms of PTSD, depression, and anxiety, and in health-related quality of life during treatment in traumatized refugees. The study group comprises 55 persons admitted to the Rehabilitation and Research Centre for Torture Victims in 2001 and 2002. Data on background, trauma, present social situation, mental symptoms (Hopkins Symptom Checklist-25, Hamilton Depression Scale, Harvard Trauma Questionnaire), and health-related quality of life (WHO Quality of Life-Bref) were collected before treatment and after 9 months. No change in mental symptoms or health-related quality of life was observed. In spite of the treatment, emotional distress seems to be chronic for the majority of this population. Future studies are needed to explore which health-related and social interventions are most useful to traumatized refugees.

Adult↗

PubMed2005

A dose-response relationship between maternal smoking during late pregnancy and adult intelligence in male offspring.

An association between maternal smoking during pregnancy and cognitive and behavioural development has been observed in several studies, but potential effects of maternal smoking on offspring adult intelligence have not been investigated. The objective of the present study was to investigate a potential association between maternal smoking during pregnancy and offspring intelligence in young adulthood. Adult intelligence was assessed at the mean age of 18.7 years by a military draft board intelligence test (Borge Priens Prove) for 3044 singleton males from the Copenhagen Perinatal Cohort with information regarding maternal smoking during the third trimester coded into five categories (about 50% of the mothers were smokers). The following potential confounders were included as covariates in multivariable analyses: parental social status and education, single mother status, mother's height and age, number of pregnancies, and gestational age. In separate analyses, birthweight and length were also included as covariates. Maternal cigarette smoking during the third trimester, adjusted for the seven covariates, showed a negative association with offspring adult intelligence (P=0.0001). The mean difference between the no-smoking and the heaviest smoking category amounted to 0.41 standard deviation, corresponding to an IQ difference of 6.2 points [95% confidence interval 0.14, 0.68]. The association remained significant when further adjusted for birthweight and length (P=0.007). Both unadjusted and adjusted means suggested a dose-response relationship between maternal smoking during pregnancy and offspring adult intelligence. When subjects with missing data were excluded, essentially the same results were obtained in the reduced sample (n=1829). These results suggest that smoking during pregnancy may have long-term negative consequences on offspring adult intelligence.

Adolescent↗

PubMed2005

IQ and mental disorder in young men.

BACKGROUND: Most research investigating the relationship between IQ and risk of mental disorder has focused on schizophrenia. AIMS: To illuminate the relationship between IQ test scores in early adulthood and various mental disorders. METHOD: For 3289 men from the Copenhagen Perinatal Cohort, military IQ test scores and information on psychiatric hospitalisation were available. We identified 350 men in the Danish Psychiatric Central Register, and compared the mean IQ test scores of nine diagnostic categories with the mean scores of 2939 unregistered cohort controls. RESULTS: Schizophrenia and related disorders, other psychotic disorders, adjustment, personality, alcohol and substance-use-related disorders were significantly associated with low IQ scores, but this association remained significant for the four non-psychotic disorders only when adjusting for comorbid diagnoses. For most diagnostic categories, test scores were positively associated with the length of the interval between testing and first admission. ICD mood disorders as well as neuroses and related disorders were not significantly associated with low IQ scores. CONCLUSIONS: Low IQ may be a consequence of mental disease or a causal factor in psychotic and non-psychotic disorders.

Adult↗

PubMed2004

Behavioral and social development of children born extremely premature: 5-year follow-up.

A cohort of extremely prematurely born children and matched term controls was assessed at 5 years of age. The parents completed a questionnaire on their behavioral and social development. The purpose was to illuminate whether the children's general intellectual ability and parental sensitivity were associated with behavioral and social development. The index children exhibited more hyperactive behavior and had poorer social skills than the controls. Lower Full Scale IQ (FSIQ) was associated with outward reacting and hyperactive behavior and poorer social skills. Sensitive parenting was associated with less outward reacting and less hyperactive behavior. When controlling for differences in FSIQ and parental sensitivity, the index children persisted to have an increased risk of exhibiting hyperactive behavior but not poorer social skills. The index children with normal intellectual development, however, did not exhibit more behavioral problems or poorer social skills than the control children did.

Attention Deficit and Disruptive Behavior Disorder↗

PubMed2003

[Breast feeding and intelligence].

INTRODUCTION: In several studies a positive association between breastfeeding and intellectual development in childhood has been suggested. However, the association between breastfeeding and adult intelligence is unknown, and the purpose of the present study was to investigate the relationship between duration of breastfeeding and intelligence in young adulthood. MATERIAL AND METHODS: A prospective longitudinal study based on the Copenhagen Perinatal Cohort. A mixed-sex sample comprising 973 individuals with a mean age of 27.2 years was assessed with a clinical intelligence test (WAIS) and an all-male sample comprising 2280 individuals was assessed with a military intelligence test (BPP) at the mean age of 18.7 years. Based upon duration of breastfeeding, the samples were divided into five categories. Thirteen potential confounders were included as covariates: Parental social status and education, single mother status, mother's height, age, weight gain during pregnancy, and cigarette consumption during the third trimester, number of pregnancies, estimated gestational age, birth weight, birth length, and indexes of pregnancy and delivery complications. RESULTS: Duration of breastfeeding was associated with significantly higher scores on both the verbal and performance parts of the WAIS. With regression adjustment for potential confounding factors, the full scale IQs were 99.4, 101.7, 102.3, 106.0, and 104.0 for breastfeeding durations of < or = 1 month, 2-3 months, 4-6 months, 7-9 months, and > 9 months (p = 0.003). The corresponding mean scores for the BPP were 38.0, 39.2, 39.9, 40.1, and 40.1 (p = 0.01). Thus, the mean test scores suggested a dose-response relationship for breastfeeding during the first nine months of life and adult intelligence. DISCUSSION: Independent of a wide range of possible confounding factors, a significant positive association between duration of breastfeeding and intelligence was observed in two independent samples of young adults, assessed with two different intelligence tests. Although duration of breastfeeding may correlate with maternal intelligence and with the quality of mother-child interaction, these findings suggest that nutrients in breastmilk may have long-term positive effects on cognitive and intellectual development.

Adult↗

PubMed2003

Cognitive deficits in long-term survivors of childhood brain tumors: Identification of predictive factors.

BACKGROUND: To describe cognitive function and to evaluate the association between potentially predictive factors and cognitive outcome in an unselected population of survivors of childhood brain tumors. PROCEDURE: We studied a consecutive sample of 133 patients (76 had received radiotherapy (RT)) who had a brain tumor diagnosed before the age of 15 years and were treated during the period January 1970 through February 1997 in the Eastern part of Denmark. Biologic effective dose of irradiation (BED) was assessed in 71 patients. One hundred twenty-seven patients were able to cooperate to WISC-R and WAIS-R. Multiple regression models were constructed to evaluate relationships between possible risk factors and cognitive outcome. RESULTS AND CONCLUSIONS: The mean intelligence (IQ) scores were substantially lower than the expected means of the general population. Younger age at diagnosis, tumor site in cerebral hemisphere, hydrocephalus treated with shunt, and treatment with RT were found to be significant predictors of lower cognitive functions. RT was the most important risk factor for impaired intellectual outcome. The mean observed full scale IQ was 97.1 (SD = 14.3) for the non-irradiated patients and 78.8 (SD = 14.3) for the irradiated patients (adjusted P < 0.001). Verbal IQ, but not performance and full scale IQ, had a significant negative correlation to BED to the tumor site (P < 0.05). These results can be used to identify subgroups of children who are at increased risk for cognitive deficits allowing early and goal-directed intervention.

Adolescent↗