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I Janssen

Publications and source records attributed to I Janssen.

At least 19 recordsLinked to original sources

Elevated body mass index and mortality risk in the elderly.

The purpose of this report was to perform a systematic review and meta-analysis of the studies examining the impact of an elevated body mass index (BMI) on mortality risk in elderly (> or =65 years) men and women. A variance-based method of meta-analysis was used to summarize the relationships from available studies. The summary relative risk of all-cause mortality from the 26 analyses that included a risk estimate for a BMI within the overweight range was 1.00 (95% confidence intervals, 0.97-1.03). The summary relative risk of all-cause mortality for the 28 analyses that included a risk estimate for a BMI within the obese range was 1.10 (1.06-1.13). These calculations indicate that a BMI in the overweight range is not associated with a significantly increased risk of mortality in the elderly, while a BMI in the moderately obese range is only associated with a modest increase in mortality risk.

Aged↗

Attribution style and psychosis: evidence for an externalizing bias in patients but not in individuals at high risk.

BACKGROUND: The aims of the study were to investigate whether (i) patients with lifetime presence of non-affective psychosis show an external-personal attribution bias for negative events, (ii) this attribution style can also be detected in first-degree relatives of patients with psychosis and subjects with subclinical psychotic experiences, and (iii) this attribution style is related to the presence of psychotic symptoms, in particular delusions. METHOD: Participants were 23 patients with lifetime presence of non-affective psychosis, a high- risk group of 36 first-degree relatives of patients with non-affective psychosis, a high-risk group of 31 subjects with subclinical psychotic experiences and 46 normal controls. Attribution style was measured by the Internal, Personal and Situational Attribution Questionnaire. Positive symptoms were assessed with the Present State Examination (PSE) and the Scale for the Assessment of Positive Symptoms (SAPS). RESULTS: Relative to the controls, an externalizing bias was apparent in the patient group (beta = 0.20, p = 0.03) but not in the two high-risk groups. There was a dose-response association between externalizing bias and the delusions subscale of the PSE (relative to lowest level: highest level of delusions: beta = 0.53, p = 0.04; intermediate levels of delusions: beta = 0.23, p = 0.35). No significant differences were found in personalizing bias between the four groups. CONCLUSIONS: Patients with psychosis tend to use an externalizing bias in their explanations of negative social events, and this bias is associated with the presence of positive psychotic symptoms, in particular delusions. A deviant attribution style is not part of the vulnerability to psychosis.

Adolescent↗

Separate and combined influence of body mass index and waist circumference on arthritis and knee osteoarthritis.

OBJECTIVE: To determine if the combination of body mass index (BMI) and waist circumference (WC) explains an additional component of arthritis and knee osteoarthritis risk than is accounted for by either anthropometric measure alone. DESIGN: Cross-sectional study. PARTICIPANTS: Participants were part of the Third National Health and Nutrition Examination Survey, a representative sample of Americans conducted from 1988 to 1994. The arthritis analyses included 15 570 participants aged 18 years and older. The knee osteoarthritis analyses included 2323 participants aged 60 years and older. Body mass index and WC were measured in all participants and classified into sex-specific tertiles. OUTCOME MEASURES: Arthritis (determined by self-report) and knee osteoarthritis (determined by radiograph). RESULTS: Independent of sex, the likelihood of arthritis and knee osteoarthritis increased in a graded fashion when moving from the lowest to highest BMI tertile and when moving from the lowest to highest WC tertile (Ptrend < 0.01). In the next phase of analyses, subjects were divided into WC tertiles within each of the BMI tertiles. Within the lowest BMI tertile, the likelihood of arthritis and knee osteoarthritis was not different in the lowest, middle and highest WC tertiles (P > 0.1). Within the middle BMI tertile, the middle and high WC tertiles were more likely to have knee osteoarthritis compared to the lowest WC tertile (P < 0.05). Within the highest BMI tertile, the highest WC tertile was more likely to have arthritis and knee osteoarthritis compared to the lowest WC tertile (P < 0.05). CONCLUSIONS: Both BMI and WC were strong predictors of arthritis and knee osteoarthritis. When a categorical approach was used for BMI and WC, similar to that in the clinical setting, independent effects of these anthropometric variables were observed.

Adult↗

Associations between risk behavior and injury and the protective roles of social environments: an analysis of 7235 Canadian school children.

OBJECTIVE: The social etiology of adolescent injury remains poorly understood. The Population Health Framework suggests that the etiology of adolescent injury involves interactions between individual risk factors and the natures of adolescent environments. The purpose of this study was to apply this framework to examination of relationships between adolescent risk taking and injury, and the potential modifying effects of supportive home and school environments. METHODS: The analysis was conducted in a representative sample of 7235 males and females (10-16 years old) from Canada. Results were based on records from the 2001/02 World Health Organization Health Behaviour in School-Aged Children Survey. Individual items and factor analytically derived scales were used to describe and then model injury outcomes, risk behaviors, perceived home, and school climates, and the relationships between these variables in a theory driven etiological analysis. RESULTS: Adolescents with supportive home and school environments experienced lower relative odds of engagement in risk taking behavior and lower relative odds of injury. Gradients were observed between the extent of adolescent risk taking and the occurrence of injury. Interactions were not observed between risk taking behavior, perceived support in home and school climates, and injury. CONCLUSIONS: Risk taking is common among adolescents and plays a role in the etiology of injury. Supportive social climates clearly protect adolescents from engaging in these behaviors, and also the occurrence of some forms of injury. However, once an adolescent chooses to engage in risk taking behaviour, a supportive environment may not protect them from injury.

Adolescent↗

Comparison of overweight and obesity prevalence in school-aged youth from 34 countries and their relationships with physical activity and dietary patterns.

The purposes of this systematic review were to present and compare recent estimates of the prevalence of overweight and obesity in school-aged youth from 34 countries and to examine associations between overweight and selected dietary and physical activity patterns. Data consisted of a cross-sectional survey of 137 593 youth (10-16 years) from the 34 (primarily European) participating countries of the 2001-2002 Health Behaviour in School-Aged Children Study. The prevalence of overweight and obesity was determined based on self-reported height and weight and the international child body mass index standards. Logistic regression was employed to examine associations between overweight status with selected dietary and physical activity patterns. The two countries with the highest prevalence of overweight (pre-obese + obese) and obese youth were Malta (25.4% and 7.9%) and the United States (25.1% and 6.8%) while the two countries with the lowest prevalence were Lithuania (5.1% and 0.4%) and Latvia (5.9% and 0.5%). Overweight and obesity prevalence was particularly high in countries located in North America, Great Britain, and south-western Europe. Within most countries physical activity levels were lower and television viewing times were higher in overweight compared to normal weight youth. In 91% of the countries examined, the frequency of sweets intake was lower in overweight than normal weight youth. Overweight status was not associated with the intake of fruits, vegetables, and soft drinks or time spent on the computer. In conclusion, the adolescent obesity epidemic is a global issue. Increasing physical activity participation and decreasing television viewing should be the focus of strategies aimed at preventing and treating overweight and obesity in youth.

Adolescent↗

Are apparent associations between parental representations and psychosis risk mediated by early trauma?

OBJECTIVE: It was investigated whether the reported association between representations of parental rearing style and psychosis does not represent a main effect, but instead is a proxy indicator of the true underlying risk factor of early trauma. METHOD: In a general population sample of 4045 individuals aged 18-64 years, first ever onset of positive psychotic symptoms at 3-year follow-up was assessed using the Composite International Diagnostic Interview and clinical interviews if indicated. Representations of parental rearing style were measured with the Parental Bonding Instrument (PBI). RESULTS: Lower baseline level of PBI parental care predicted onset of psychotic symptoms 2 years later. However, when trauma was included in the equation, a strong main effect of trauma emerged at the expense of the effect size of PBI low care. CONCLUSION: The results suggest that associations between representations of parental rearing style and psychosis may be an indicator of the effect of earlier exposure to childhood trauma.

Adolescent↗

Early trauma may increase the risk for psychotic experiences by impacting on emotional response and perception of control.

OBJECTIVE: Exposure to early trauma may increase the risk of dysfunctional responses to anomalous psychotic experiences resulting in psychotic symptom formation. METHOD: In a three-wave longitudinal general population study, 4045 never-psychotic individuals exposed and non-exposed to trauma before the age of 16 years, according to baseline interview were interviewed for the onset of psychotic experiences 3 years later (T2). In 36 individuals with incident psychosis at T2, assessments were made, for each psychotic experience, of i) the amount of distress associated with and ii) the degree of coping and subjective control over the experience. RESULTS: In the 16 observations of an incident psychotic experience, in the absence of distress, the baseline rate of early trauma was low (6%), whereas it was much higher in the 21 observations of an incident psychotic experience with distress [43%; odds ratio=10.0, 95% confidence interval (CI): 1.04, 96.3; P=0.046]. Similarly, coping attempts in the context of early trauma was associated with less control (reduction of 2 points on a seven-point scale, 95% CI: -4.0, -0.07). CONCLUSION: Early experience of trauma may create lasting cognitive and affective vulnerabilities to develop clinical symptoms arising out of early, non-clinical psychotic experiences.

Adaptation, Psychological↗

Cross national study of injury and social determinants in adolescents.

OBJECTIVES: To compare estimates of the prevalence of injury among adolescents in 35 countries, and to examine the consistency of associations cross nationally between socioeconomic status then drunkenness and the occurrence of adolescent injury. DESIGN: Cross sectional surveys were obtained from national samples of students in 35 countries. Eight countries asked supplemental questions about injury. SETTING: Surveys administered in classrooms. SUBJECTS: Consenting students (n = 146 440; average ages 11-15 years) in sampled classrooms. 37 878 students (eight countries) provided supplemental injury data.Exposure measures: Socioeconomic status (material wealth, poverty) and social risk taking (drunkenness). OUTCOME MEASURES: Specific types and locations of medically treated injury. RESULTS: By country, reports of medically treated injuries ranged from 33% (1060/3173) to 64% (1811/2833) of boys and 23% (740/3172) to 51% (1485/2929) of girls, annually. Sports and recreation were the most common activities associated with injury. High material wealth was positively (OR>1.0; p<0.05) and consistently (6/8 countries) associated with medically treated and sports related injuries. Poverty was positively associated with fighting injuries (6/8 countries). Drunkenness (social risk taking) was positively (p<0.01) and consistently (8/8 countries) associated with medically treated, street, and fighting injuries, but not school and sports related injuries. CONCLUSION: The high prevalence of adolescent injury confirms its importance as a health problem. Social gradients in risk for adolescent injury were illustrated cross nationally for some but not all types of adolescent injury. These gradients were most evident when the etiologies of specific types of adolescent injury were examined. Prevention initiatives should focus upon the etiologies of specific injury types, as well as risk oriented social contexts.

Adolescent↗

Childhood abuse as a risk factor for psychotic experiences.

OBJECTIVE: To examine the hypothesis that individuals from the general population who report childhood abuse are at increased risk of developing positive psychotic symptoms. METHOD: Data were derived from a general population sample of 4045 subjects aged 18-64 years. First ever onset of positive psychotic symptoms at 2-year follow-up were assessed using the Composite International Diagnostic Interview and additional clinical interviews if necessary. Childhood abuse was assessed at baseline. RESULTS: Baseline reported childhood abuse predicted development of positive psychotic symptoms associated with need for care [odds ratio (OR) = 11.5, 95% CI 2.6-51.6]. This association remained after adjustment for demographic variables, reported risk factors and presence of any lifetime psychiatric diagnosis at baseline (OR = 7.3, 95% CI 1.1-49.0). CONCLUSION: The results suggest that early childhood trauma increases the risk for positive psychotic symptoms. This finding fits well with recent models that suggest that early adversities may lead to psychological and biological changes that increase psychosis vulnerability.

Adolescent↗

Alterations in theory of mind in patients with schizophrenia and non-psychotic relatives.

OBJECTIVE: It has been proposed that alterations in theory of mind underlie specific symptoms of psychosis. The present study examined whether alterations in theory of mind reflect a trait that can be detected in non-psychotic relatives of patients with schizophrenia. METHOD: Participants were 43 patients with schizophrenia or schizoaffective disorder, 41 first-degree non-psychotic relatives and 43 controls from the general population. Theory of mind was assessed using a hinting task and a false-belief task. RESULTS: There was a significant association between schizophrenia risk and failure on the hinting task (OR linear trend = 2.01, 95% CI: 1.22-3.31), with relatives having intermediate values between patients and controls. Adjustment for IQ and neuropsychological factors reduced the association by small amounts. The association between schizophrenia risk and failure on the false-belief tasks was not significant. CONCLUSION: Changes in theory of mind are associated with schizophrenia liability. General cognitive ability and neuropsychological measures seem to mediate only part of this association.

Adult↗

Physical inactivity, excess adiposity and premature mortality.

The purpose of this report is to review the evidence that physical inactivity and excess adiposity are related to an increased risk of all-cause mortality, and to better identify the independent contributions of each to all-cause mortality rates. A variance-based method of meta-analysis was used to summarize the relationships from available studies. The summary relative risk of all-cause mortality for physical activity from the 55 analyses (31 studies) that included an index of adiposity as a covariate was 0.80 [95% confidence interval (CI) 0.78-0.821, whereas it was 0.82 [95% CI 0.80-0.84] for the 44 analyses (26 studies) that did not include an index of adiposity. Thus, physically active individuals have a lower risk of mortality by comparison to physically inactive peers, independent of level of adiposity. The summary relative risk of all-cause mortality for an elevated body mass index (BMI) from the 25 analyses (13 studies) that included physical activity as a covariate was 1.23 [95% CI 1.18-1.29], and it was 1.24 [95% CI 1.21-1.28] for the 81 analyses (36 studies) that did not include physical activity as a covariate. Studies that used a measure of adiposity other than the BMI show similar relationships with mortality, and stratified analyses indicate that both physical inactivity and adiposity are important determinants of mortality risk.

Adipose Tissue↗

Discrimination and delusional ideation.

BACKGROUND: In the UK and The Netherlands, people with high rates of psychosis are chronically exposed to discrimination. AIMS: To test whether perceived discrimination is associated longitudinally with onset of psychosis. METHOD: A 3-year prospective study of cohorts with no history of psychosis and differential rates of reported discrimination on the basis of age, gender, disability, appearance, skin colour or ethnicity and sexual orientation was conducted in the Dutch general population (n=4076). The main outcome was onset of psychotic symptoms (delusions and hallucinations). RESULTS: The rate of delusional ideation was 0.5% (n=19) in those who did not report discrimination, 0.9% (n=4) in those who reported discrimination in one domain, and 2.7% (n=3) in those who reported discrimination in more than one domain (exact P=0.027). This association remained after adjustment for possible confounders. No association was found between baseline discrimination and onset of hallucinatory experiences. CONCLUSIONS: Perceived discrimination may induce delusional ideation and thus contribute to the high observed rates of psychotic disorder in exposed minority populations.

Adolescent↗

Captopril, a specific inhibitor of angiotensin converting enzyme, enhances both trypsin and vitellogenin titers in the grey fleshfly Neobellieria bullata.

A strong and constitutive angiotensin converting enzyme- or ACE-like activity was demonstrated in the hemolymph of the adult grey fleshfly Neobellieria bullata. In a competition assay, the N. bullata trypsin modulating oostatic factor (Neb-TMOF) was confirmed to be an in vitro substrate for this circulating Neb-ACE. Oral uptake of captopril, a selective and specific inhibitor of ACE, resulted in a complete phenotypic knockout of circulating ACE activity. When compared with control animals, captopril-fed female flies showed an increase in the liver meal-induced trypsin peak in the midgut and elevated levels of protein meal-induced yolk polypeptides in the hemolymph. The latter effect was not due to a slower vitellogenin uptake by the ovaries, because oocyte growth was not affected by the captopril treatment. The apparent synergism between the demonstrated ACE functionality and the previously reported effects of the oostatic peptide Neb-TMOF are discussed in the context of our recent finding that Neb-TMOF represents a prime candidate for being the first known in vivo substrate for circulating insect ACE. Arch.

Angiotensin-Converting Enzyme Inhibitors↗

Cyclooxygenase expression in microglia and neurons in Alzheimer's disease and control brain.

Epidemiological studies suggest that non-steroidal anti-inflammatory drugs (NSAIDs) lower the risk of developing Alzheimer's disease (AD). Most NSAIDs act upon local inflammatory events by inhibiting the expression or activation of cylooxygenase (COX). In the present study the expression of COX-1 and COX-2 in AD and non-demented control temporal and frontal cortex was investigated using immunohistochemistry. COX-1 expression was detected in microglial cells, while COX-2 expression was found in neuronal cells. In AD brains, COX-1-positive microglial cells were primarily associated with amyloid beta plaques, while the number of COX-2-positive neurons was increased compared to that in control brains. No COX expression was detected in astrocytes. In vitro, primary human microglial and astrocyte cultures, and human neuroblastoma cells (SK-N-SH) were found to secrete prostaglandin E2 (PGE2), especially when stimulated. PGE2 synthesis by astrocytes and SK-N-SH cells was stimulated by interleukin-1beta. Microglial cell PGE2 synthesis was stimulated by lipopolysaccharide only. Although astrocytes are used in studies in vitro to investigate the role of COX in AD, there are no indications that these cells express COX-1 or COX-2 in vivo. The different distribution patterns of COX-1 and COX-2 in AD could implicate that these enzymes are involved in different cellular processes in the pathogenesis of AD.

Aged↗

Interleukin-1beta induced cyclooxygenase 2 expression and prostaglandin E2 secretion by human neuroblastoma cells: implications for Alzheimer's disease.

Non-steroidal anti-inflammatory drugs (NSAIDs) may decrease the risk of developing Alzheimer's disease (AD). Cyclooxygenase 2 (COX-2), one of the targets of NSAIDs, is increasingly expressed in neuronal cells in AD brain. In this study, of the cytokines that are found at increased levels in AD brain (interleukin (IL)-1alpha, IL-1beta, IL-6 and tumour necrosis factor (TNF)alpha), IL-1beta was found to induce COX-2 immunoreactivity and prostaglandin (PG) E2 secretion by human neuroblastoma cell line SK-N-SH. COX inhibitors indomethacin and BF389, as well as the glucocorticoid dexamethasone (DEX) and pyrrolidinedithiocarbamate, which is an inhibitor of nuclear factor kappaB as well as a potent antioxidant, inhibited IL-1beta induced PGE2 secretion. In addition, DEX reduced the IL-1beta induced COX-2 immunoreactivity in the same concentration as wherein it inhibited PGE2 secretion. Palmitoyl trifluormethyl ketone, an inhibitor of Ca(2+) independent phospholipase A2 (iPLA2) and a less potent inhibitor of cytosolic PLA2, dose-dependently reduced the IL-1beta induced PGE2 secretion. This suggests that the IL-1beta induced PGE2 secretion may depend on the availability of arachidonic acid. Although the physiological role of neuronal COX-2 still remains unclear, we suggest an interplay between glial derived IL-1 and neuronal upregulation of COX-2 expression in chronic neurodegenerative diseases, such as AD.

Alzheimer Disease↗

Physical activity, total and regional obesity: dose-response considerations.

PURPOSE: This review was undertaken to determine whether exercise-induced weight loss was associated with corresponding reductions in total, abdominal, and visceral fat in a dose-response manner. METHODS: A literature search (MEDLINE, 1966--2000) was performed using appropriate keywords to identify studies that consider the influence of exercise-induced weight loss on total and/or abdominal fat. The reference lists of those studies identified were cross-referenced for additional studies. RESULTS: Total fat. Review of available evidence suggested that studies evaluating the utility of physical activity as a means of obesity reduction could be subdivided into two categories based on study duration. Short-term studies (< or = 16 wk, N = 20) were characterized by exercise programs that increased energy expenditure by values double (2200 vs 1100 kcal.wk-1) that of long-term studies (> or = 26 wk, N = 11). Accordingly, short-term studies report reductions in body weight (-0.18 vs -0.06 kg x wk(-1)) and total fat (-0.21 vs -0.06 kg x wk(-1)) that are threefold higher than those reported in long-term studies. Moreover, with respect to dose-response issues, the evidence from short-term studies suggest that exercise-induced weight loss is positively related to reductions in total fat in a dose-response manner. No such relationship was observed when the results from long-term studies were examined. Abdominal fat. Limited evidence suggests that exercise-induced weight loss is associated with reductions in abdominal obesity as measured by waist circumference or imaging methods; however, at present there is insufficient evidence to determine a dose-response relationship between physical activity, and abdominal or visceral fat. CONCLUSION: In response to well-controlled, short-term trials, increasing physical activity expressed as energy expended per week is positively related to reductions in total adiposity in a dose-response manner. Although physical activity is associated with reduction in abdominal and visceral fat, there is insufficient evidence to determine a dose-response relationship.

Abdomen↗

Reduction in obesity and related comorbid conditions after diet-induced weight loss or exercise-induced weight loss in men. A randomized, controlled trial.

BACKGROUND: The independent effects of diet- or exercise-induced weight loss on the reduction of obesity and related comorbid conditions are not known. The effects of exercise without weight loss on fat distribution and other risk factors are also unclear. OBJECTIVE: To determine the effects of equivalent diet- or exercise-induced weight loss and exercise without weight loss on subcutaneous fat, visceral fat skeletal muscle mass, and insulin sensitivity in obese men. DESIGN: Randomized, controlled trial. SETTING: University research center. PARTICIPANTS: 52 obese men (mean body mass index [+/-SD], 31.3 +/- 2.0 kg/m2) with a mean waist circumference of 110.1 +/- 5.8 cm. INTERVENTION: Participants were randomly assigned to one of four study groups (diet-induced weight loss, exercise-induced weight loss, exercise without weight loss, and control) and were observed for 3 months. MEASUREMENTS: Change in total, subcutaneous, and visceral fat; skeletal muscle mass; cardiovascular fitness; glucose tolerance and insulin sensitivity. RESULTS: Body weight decreased by 7.5 kg (8%) in both weight loss groups and did not change in the exercise without weight loss and control groups. Compared with controls, cardiovascular fitness (peak oxygen uptake) in the exercise groups improved by approximately 16% (P < 0.01). Although total fat decreased in both weight loss groups (P < 0.001), the average reduction was 1.3 kg (95% CI, 0.3 to 2.3 kg) greater in the exercise-induced weight loss group than in the diet-induced weight loss group (P = 0.03). Similar reductions in abdominal subcutaneous, visceral, and visceral fat-to-subcutaneous fat ratios were observed in the weight loss groups (P < 0.001). Abdominal and visceral fat also decreased in the exercise without weight loss group (P = 0.001). Plasma glucose and insulin values (fasting and oral glucose challenge) did not change in the treatment groups compared with controls (P = 0.10 for all comparisons). Average improvement in glucose disposal was similar in the diet-induced weight loss group (5.6 mg/kg skeletal muscle per minute) and in the exercise-induced weight loss group (7.2 mg/kg skeletal muscle per minute) (P > 0.2). However, these values were significantly greater than those in the control and exercise without weight loss groups (P < 0.001). CONCLUSIONS: Weight loss induced by increased daily physical activity without caloric restriction substantially reduces obesity (particularly abdominal obesity) and insulin resistance in men. Exercise without weight loss reduces abdominal fat and prevents further weight gain.

Abdomen↗

Daily social and physical activity increases slow-wave sleep and daytime neuropsychological performance in the elderly.

Decreased levels of physical and social activity associated with aging can be particularly pronounced in residents of assisted living facilities. Reduced exposure to important behavioral and time-giving cues may contribute to the age-related changes in circadian rhythmicity and sleep. The present study was conducted to test the hypothesis that an enforced schedule of structured social and physical activity (0:900 to 10:30 and 19:00 to 20:30 daily for two weeks) can have beneficial effects on circadian rhythmicity, nocturnal sleep, daytime functioning, mood, and vigor. The subjects were 14 elderly residents of continued-care retirement facilities while a similar group of 9 elderly residents served as controls. The group exposed to structured activities had increased amounts of slow-wave sleep and demonstrated improvement in memory-oriented tasks following the intervention. Conversely, no significant changes were noted in the amplitude and phase of the body temperature rhythm or in subjective measures of vigor and mood. These results indicate that short-term exposure to structured social intervention and light physical activity can significantly improve memory performance and enhance slow-wave sleep in older adults without alterations to the circadian phase or amplitude of body temperature. This is the first report to demonstrate that low intensity activity in an elderly population can increase deep sleep and improve memory functioning. The high degree of interest in these activities paired with the simple nature of the tasks makes this a potentially practical intervention which can be adapted for both community dwelling and assisted-living elders.

Adult↗