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Background: More so than the traditional socioeconomic indicators, such as education and income, wealth reflects the accumulation of resources and makes socioeconomic ranking manifest and explicitly visible to the outside world. While the lack of basic goods, such as a refrigerator, may affect health directly, via biological pathways, the lack of luxury goods, such as an LCD television, may affect health indirectly through psychosocial mechanisms. We set out to examine, firstly, the relevance of both basic and luxury goods in explaining health-related dysfunction in older persons, and, secondly, the extent to which these associations are independent of traditional socioeconomic indicators., Methods: Cross-sectional and longitudinal data from 2067 men and women aged 55 years and older who participated in the Study on Medical Information and Lifestyles Eindhoven (SMILE) were gathered. Logistic regression analyses were used to study the relation between a lack of basic and luxury goods and health-related function, assessed with two sub-domains of the SF-36., Results: The lack of basic goods was closely related to incident physical (OR = 2.32) and mental (OR = 2.12) dysfunction, even when the traditional measures of socioeconomic status, i.e. education or income, were taken into account. Cross-sectional analyses, in which basic and luxury goods were compared, showed that the lack of basic goods was strongly associated with mental dysfunction. Lack of luxury goods was, however, not related to dysfunction., Conclusion: Even in a relatively wealthy country like the Netherlands, the lack of certain basic goods is not uncommon. More importantly, lack of basic goods, as an indicator of wealth, was strongly related to health-related dysfunction also when traditional measures of socioeconomic status were taken into account. In contrast, no effects of luxury goods on physical or mental dysfunction were found. Future longitudinal research is necessary to clarify the precise mechanisms underlying these effects.

Objective: To assess the psychometric properties of the Patient Health Questionnaire-9 (PHQ-9) as a screening instrument for depression in elderly patients with diabetes mellitus (DM) and chronic obstructive pulmonary disease (COPD) without known depression., Study Design and Setting: DM and COPD patients aged >59 years were selected from general practices. A test-retest was conducted in 105 patients. Criterion validity, using the Mini International Neuropsychiatric Interview psychiatric interview to diagnose major depressive disorder (MDD) and any depressive disorder (ADD) as diagnostic standard, was evaluated for both summed and algorithm-based PHQ-9 score in 713 patients. Correlations with quality of life and severity of illness were calculated to assess construct validity., Results: Cohen's kappa for the algorithm-based score was 0.71 for MDD and 0.69 for ADD. Correlation for test-retest assessment of the summed score was 0.91. The algorithm-based score had low sensitivity and high specificity, but both sensitivity and specificity were high for the optimal cut-off point of 6 on the summed score for ADD (Se 95.6%, Sp 81.0%). Correlations between summed score and quality of life and severity of illness were acceptable., Conclusion: The summed PHQ-9 score seems a valid and reliable screening instrument for depression in elderly primary care patients with DM and COPD.

Objective: This article describes the process evaluation of the Depression in Elderly with Long-Term Afflictions (DELTA) intervention, a nurse-led minimal psychological intervention to reduce depression in chronically ill elderly persons. The aim was to assess whether the DELTA intervention was implemented and received as planned, which barriers were encountered and whether nurses and patients were satisfied with the intervention., Methods: Quantitative and qualitative data were gathered from all 183 patients who participated in the intervention and from four nurses who administered the intervention. Data were assessed by means of self-administered questionnaires, checklists, and a group interview with the nurses., Results: Although several barriers were encountered, the intervention was well performed by nurses and well received by patients. However, a small proportion of the patients found the intervention not useful and thought they would not benefit., Conclusion: The implementation of the minimal psychological intervention aimed at reducing depression in chronically ill elderly persons was successful and therefore feasible., Practice Implications: By making the intervention part of regular care for patients with a chronic condition, patients can be monitored and, if necessary, support can be provided to implement the intervention in their daily life.

Background: The aims of this study were to examine the extent to which higher intellectual abilities protect higher socio-economic groups from functional decline and to examine whether the contribution of intellectual abilities is independent of childhood deprivation and low birth weight and other socio-economic and developmental factors in early life., Methods: The Maastricht Aging Study (MAAS) is a prospective cohort study based upon participants in a registration network of general practices in The Netherlands. Information was available on 1211 men and women, 24-81 years old, who were without cognitive impairment at baseline (1993-1995), who ever had a paid job, and who participated in the six-year follow-up. Main outcomes were longitudinal decline in important components of quality of life and successful aging, i.e., self-reported physical, affective, and cognitive functioning., Results: Persons with a low occupational level at baseline showed more functional decline than persons with a high occupational level. Socio-economic and developmental factors from early life hardly contributed to the adult socio-economic differences in functional decline. Intellectual abilities, however, took into account more than one third of the association between adult socio-economic status and functional decline. The contribution of the intellectual abilities was independent of the early life factors., Conclusion: Rather than developmental and socio-economic characteristics of early life, the findings substantiate the importance of intellectual abilities for functional decline and their contribution--as potential, but neglected confounders--to socio-economic differences in functioning, successful aging, and quality of life. The higher intellectual abilities in the higher socio-economic status groups may also underlie the higher prevalences of mastery, self-efficacy and efficient coping styles in these groups.

Objective: To determine whether socio-economic differences in hospital admissions of adolescents and young adults are related to differences in intelligence., Design: . Retrospective cohort study., Methods: The data were derived from a group of 10,231 young adults and adolescents who were followed for a total of 47,212 person years with regard to their hospital admissions. Intelligence was measured in the first year of secondary school by 2 non-verbal intelligence tests for fluid intelligence. Data from hospital admissions were matched to a large-scale educational and occupational cohort. Data were analysed with Cox proportional hazards analysis., Results: Intelligence was not found to be related to hospital admissions. However, a low occupational and educational level of the young adults or their parents, was strongly related to heightened risk for hospital admissions. In particular, the low socio-economic status of a respondent was associated with heightened risk for hospital admissions due to accidents (relative risk: 3.49; 95% confidence interval: 1.91-6.39)., Conclusion: The small extent to which the socio-economic differences in hospital admissions seem to be based upon fluid intelligence, at least in adolescents and young adults, as well as the heightened risks of hospital admissions in lower socio-economic status groups and the associated high costs for health care legitimise further study of the determinants of these differences.

Objectives: We examined whether healthy lifestyles are associated with absence of depressed mood., Methods: A sample of 1169 adult participants in the Maastricht Aging Study provided baseline and 6-year follow-up data on smoking, alcohol use, physical exercise, body mass index, and mood. We examined associations between lifestyles and depressed mood using longitudinal analyses controlling for baseline depressive symptoms and covariates., Results: Reports of excessive alcohol use at baseline predicted depressed mood at follow-up (relative risk [RR] = 2.48; 95% confidence interval [CI] = 1.08, 5.69), and reports of more than 30 minutes of physical exercise per day at baseline were associated with an absence of depressed mood at follow-up (RR=0.52; 95% CI=0.29, 0.92). Reports of being engaged in physical exercise throughout the 6-year follow-up period were also associated with absence of depressed mood (RR=0.56; 95% CI=0.34, 0.93)., Conclusions: In this relatively healthy population sample, certain lifestyles either predicted or protected against depressed mood. Adopting or maintaining healthy lifestyles might be a starting point in preventing or treating depressed mood over time.

Objective: The objective of this study was to investigate the effects of a structured 6-week neuropsychological course on the executive functioning of older adults with cognitive complaints., Methods: A randomised controlled design was used involving 69 community dwelling individuals aged 55 years and older. Both objective and subjective measures were included to assess executive functioning. General linear model with repeated measures analysis of variance was used to examine the intervention effects., Results: After the intervention, the participants in the intervention group were significantly less annoyed by their cognitive failures, were better able to manage their executive failures and reported less anxiety symptoms than those in the waiting list control group., Conclusion: These findings indicate that a combination of psycho-education and training has the potential to change the attitude of older individuals towards their cognitive functioning., Practice Implications: Because this training focussed on cognitive functions that are among the first to decline in older adults and the subjective evaluation of the people after training was quite favourable, the proposed intervention may be considered a valuable contribution to cognitive interventions for older adults.

Objective: The objective of this study was to examine the association between socioeconomic status (SES) and the onset of depression in older adults and to determine the relative contribution of psychosocial factors, physical health status, and behavioral factors in explaining this link., Methods: Data were from 2593 men and women, aged 55-85 years, participating in the Longitudinal Aging Study Amsterdam. Two indicators of SES were used: education and income. The onset of depression was measured over 9 years of follow-up., Results: Adjusted hazard ratios of incident depression were significantly higher in those with low education and low income. Psychosocial factors explained on average 16% of the SES differences in incident depression, physical health status on average 7%, and behavioral factors less than 5%., Conclusion: In older adults, low SES predicted the incidence of depression. Part of this association was explained by psychosocial factors and physical health status.

Background: This study examines the association between socioeconomic status and changes in physical function in younger- (aged 55-70 years) and older-old (aged 70-85 years) adults and seeks to determine the relative contribution of diseases, behavioral, and psychosocial factors in explaining this association., Methods: Data were from 2,366 men and women, aged 55-85 years, participating in the Longitudinal Aging Study Amsterdam (LASA). Two indicators of socioeconomic status were used: education and income. Physical function was measured by self-reported physical ability over nine years of follow-up., Results: In older adults, low socioeconomic status was related to a poorer level of physical function during nine years of follow-up. In subjects who were between 55 and 70 years old, there was an additional significant socioeconomic-differential decline in physical function, while socioeconomic differentials did not further widen in subjects 70 years and older. Behavioral factors, mainly BMI and physical activity, largely explained the socioeconomic differences in physical function in the youngest age group, while psychosocial factors reduced socioeconomic status differences most in the oldest age group., Conclusion: The findings indicate age-specificity of both the pattern of socioeconomic status differences in function in older persons and the mechanisms underlying these associations.

Objectives: Medical education should prepare students for future clinical practice. However, this preparation is inadequate for the most prevalent problem in health care: chronic disease. This applies to the continuous aspect of chronic disease. Within the context of a newly developed programme, we investigated what makes a chronic patient interesting in the eyes of medical students, what they learned from a specific programme in which each student had contact with a chronic patient 4 times in 8 months, and what they learned from their patients., Methods: A total of 240 Year 3 students were enrolled in the programme, 89 of whom filled in questionnaires at both the start and end of the programme. Topics included the characteristics of the ideal and the actual patient, the Ideal Physician Questionnaire, and several questions on the expected and actual amount of knowledge gained from the patient., Results: Students preferred patients who demonstrated clear symptoms and had frequent contacts with health care professionals during the programme to 'well adapted' patients. The perceived knowledge obtained from the patient was less than they had expected at the start of the programme. A didactic gain perceived as low was mainly due to low expectations of gaining knowledge at the start of the programme, a doctor-centred attitude and a high level of discrepancy between the student's ideal patient and the actual patient., Conclusions: Programmes that aim to present chronic patients to medical students focus on patient selection so that patients who differ only very slightly from healthy persons are eliminated. In addition, realistic information on the types of patients with whom students can expect to have contact may help students appreciate the knowledge to be gained from these patients.

Objectives: Primitive reflexes (PR) generally disappear early in life but may reappear later, in which case they are often associated with chronic neurological conditions, such as dementia or Parkinson's disease. Studies have shown that the presence of PRs may be indicative of both the severity and rate of progression of these diseases and may be the result of disinhibition of cortical networks. The association between PRs and cognitive function in usual ageing is unclear. We investigated whether the occurrence, amplitude, and persistence of four nociceptive (glabbelar tap, palmomental, pollicomental, and snout reflexes), three prehensile reflexes (suck, palmar grasp, and rooting), and two other reflexes (mouth open finger-spread and nuchocephalic reflexes) were related to performance in specific cognitive domains in normal ageing individuals., Methods: Four-hundred and seventy normal aging participants (25-82 years) in the Maastricht Aging Study (MAAS), were included in the study. They were neurologically and cognitively screened at baseline and were retested after 3 (only individuals aged 50 years and older at baseline) and 6 years., Results: The prevalence of most PRs increased with age: 47% of men aged 25-45 years had at least one PR, compared with 73% of men aged 65-85 year (p = 0.002). In women these percentages were 51 and 75, respectively (p=0.008). The prevalence, amplitude, and persistence of PRs were unrelated to cognition at baseline or at the 3- or 6-year follow-up., Conclusions: The prevalence of particularly nociceptive reflexes rises substantially with increasing age in normal individuals. However, the presence of PRs cannot be considered to be a marker of cognitive decline in normal aging individuals.

The purpose of this study was to examine the relationship between memory self-efficacy (MSE) and a 6-year follow-up assessment of memory functioning in a sample of Dutch older adults. MSE was assessed by a Dutch abridged version of the Metamemory in Adulthood questionnaire (MIA; R. A. Dixon, D. F. Hultsch, & C. Hertzog, 1988; C. Hertzog, D. F. Hultsch, & R. A. Dixon, 1989; R. W. H. M. Ponds & J. Jolles, 1996). The total MSE score predicted memory performance at 6 years, as measured by the Visual Verbal Learning Task (VVLT; N. Brand & J. Jolles, 1985). A separate analysis of the different MSE subscales indicated that the MIA Change score was the most salient domain-specific MSE predictor of subsequent memory performance after 6 years. An extreme groups analysis of the MIA Change score revealed a pattern of performance for those who perceived that their memory was worsening, performing less well on the 3 trials of the VVLT when these were readministered at the 6-year follow-up., (((c) 2006 APA, all rights reserved).)

Background: To date, it remains unclear to what extent cognitive competence is related to a change in general functional status in older adults., Objectives: To evaluate both the cross-sectional and the longitudinal relation between cognitive functioning and functional status., Methods: Sensorimotor speed, memory, and executive functioning were assessed in a large population of healthy adults aged 60 years and older (n = 485) who participated in the Maastricht Aging Study. Data from the baseline (1993-1995), three-year follow-up, and six-year follow-up were used. Functional status was measured using the SF-36, which was coded into a physical and a mental component summary measure., Results: After adjustment for age, sex, and educational level, a high level of cognitive functioning appeared to be associated with better functional status in the cross-sectional analysis. Longitudinal analyses demonstrated, that cognitive functioning was not a predictor of functional status three or six years later., Conclusions: Thus while cognitive functioning is useful clinically for predicting the short-term functional status of an older person, it is not useful for predicting that person's long-term (>3 years) functional status and thus the period of validity of the results of these tests in answering such questions is limited., (Copyright (c) 2005 John Wiley & Sons, Ltd.)

Introduction: This article reports a prospective study that focused on the influence of organizational structure and organizational culture on the outcome of sickness absence, return to work or work disability. Former studies of determinants of work disability hardly have given attention to organizational characteristics and, if so, not following a appropriate prospective design., Methods: The study population consisted of 455 employees of 45 for-profit and not-for-profit companies participating in the Maastricht Cohort Study on fatigue at work who were on sick leave for at least 6 weeks. Both independent variables which were type of company, size, centralization of decision making and organizational culture, and covariates, which were sex, age, educational level, fatigue, and chronic illness, were all measured before employees reported sick. The dependent variable outcome of the sickness absence, mainly return to work or work disability, was measured 15 months after reporting sick., Results: Multilevel logistic regression analysis, with organizational characteristics as level 2 independent variables and demographic and health characteristics as covariates, suggested that the type of company (for-profit/private or not-for-profit/public) is predictive of the outcome of sickness absence (crude OR = 2.21; CI: 1.16-4.20), but this may be partially due to a higher proportion of fatigued and chronically ill employees in not-for-profit companies (adjusted OR = 2.09; CI: 0.93-4.37). Findings about the role of some other organizational characteristics, like organizational culture, were inconclusive., Conclusions: Organizational characteristics should next to health characteristics be included in the models of studies which aim at predicting which sick employees are at risk for work disability. To prevent work disability not-for-profit companies might be stimulated to more active return-to-work policy by charging them with the costs of it.

Objective: To determine whether income is connected with the variation in the social exclusion of chronically ill patients., Design: Descriptive., Method: In 223 chronically ill patients that had been detected via patients' associations, general practitioners and outpatient clinics, a structured interview was administered during a home visit 4 times during a period of 7 months (October 2003-April 2004). Due to dropouts, the actual number of patients interviewed at each of the 4 times was 223, 176, 143 and 105, respectively. Social exclusion was measured with the aid of the 'Autonomy outside the home' subscale of the 'Impact on participation and autonomy' questionnaire. The possible total score varied from 5 (little social exclusion) to 25 (much social exclusion). In order to explain a possible effect of income, various other patient characteristics were added to the analysis model: type of primary disease (rheumatism, multiple sclerosis, pulmonary emphysema, other), duration of the primary disease, comorbidity, educational level, whether or not the patient was employed or engaged in volunteer work, whether or not the patient lived together with a partner, the self-rated health, physical functioning, social functioning, mental functioning, and the subjective pain. The data were analysed by means of multilevel repeated regression analysis., Results: A low income was associated with social exclusion at all 4 times of measurement. The regression coefficient of income was -1.47 (95% CI: -2.28- -0.65), indicating that the score on the scale for social exclusion decreased by 1.47 for every euro 544,- (= 1 x SD) increase in net monthly income. This relationship could not be explained by the other patient characteristics, not even by a low educational level., Conclusion: The supportive care intended for the prevention of social exclusion of chronically ill patients should be concentrated sufficiently on those who have too little income to organise such care for themselves.

In chronically ill patients, mobility develops more unfavorably in persons with low socio-economic status (SES) than in their better-off counterparts. Using longitudinal data from the Dutch GLOBE study (a study of health and living conditions in Eindhoven and its surroundings), the present study examines whether psychosocial factors can explain socio-economic differences in mobility decline, independent of disease severity, co-morbidity, and health-related behavior in a chronically ill population. Data were from 1384 men and woman, aged 15-74 years, suffering from at least one of the four chronic diseases: asthma/COPD, heart disease, diabetes mellitus, and low back pain. Three indicators of SES were used: education, occupational class, and income. Change in physical mobility between 1991 and 1997 was measured with the Nottingham Health Profile (NHP). Psychosocial factors were measured extensively and included life events, long-term difficulties, coping styles, social support, and personality characteristics. Low occupational level and low income predicted an increased risk of mobility decline in comparison to people with a higher occupational level and income, even after controlling for sociodemographics, disease severity, co-morbidity, and health-related behavior. Additional adjustment for psychosocial factors hardly reduced the SES-related odds ratios of mobility decline. We conclude that psychosocial factors (and also health-related behaviors, disease severity and co-morbidity) cannot explain socio-economic differences in mobility decline in a chronically ill population. Our findings will not give us new tools for prevention and intervention strategies in order to reduce physical disability and particularly the SES differences therein.

The objective of the study was to examine the effectiveness of two types of memory training (collective and individual), compared to control (waiting list), on memory performance. Participants were 139 community-dwelling older individuals recruited through media advertisements asking for people with subjective memory complaints to participate in a study. Data were collected at baseline, and at 1 week and 4 months after the intervention. Training efficacy was assessed using measures of subjective and objective memory performance. After the intervention, participants in the collective training group reported more stability in memory functioning and had fewer feelings of anxiety and stress about memory functioning. In addition, positive effects were found on objective memory functioning. Compared with the other two groups, the collective training group participants had an improved recall of a previously learned word list. Compared to controls, participants in the individual training group reported fewer feelings of anxiety and stress in relation to memory functioning.

Objectives: To examine the longitudinal relationship between sensory functioning and a broad range of cognitive functions after 6 years follow-up and whether cataract surgery or first-time hearing aid use affected cognition., Design: Hierarchical regression procedures were employed to determine whether sensory functioning was predictive of cognitive performance., Setting: Maastricht University and the University Hospital Maastricht, the Netherlands., Participants: Older Dutch adults (>/=55) enrolled in the Maastricht Aging Study (N=418)., Measurements: Visual and auditory acuity, the Visual Verbal Learning Test (VVLT), the Stroop Color Word Test (SCWT), the Concept Shifting Task (CST), the Verbal Fluency Test, and the Letter-Digit Substitution Test (LDST)., Results: A change in visual acuity was associated with change in most cognitive measures, including the total and recall scores of the VVLT, the mean score of the first two SCWT cards, the mean score of the first two CST cards and the LDST. In addition, a change in auditory acuity predicted change in memory performance (VVLT total and recall scores), and auditory acuity measured at baseline predicted change in the mean score of the first two SCWT cards and the LDST., Conclusion: The findings support the notion of a strong connection between sensory acuity in auditory and visual domains and cognitive performance measures, both from a cross-sectional and a longitudinal perspective. They also suggest that it is essential to screen older individuals in a clinical context for sensory functioning so that changes in visual or auditory acuity are not interpreted as changes in cognitive performance.

The objective of this study was to examine whether it is through their low control beliefs that low socio-economic status groups have higher risks of heart disease, and to examine whether this mechanism is more substantial than and independent of the mechanism via classical coronary risk factors. In a population-based prospective cohort study, participants were selected from 27 general practices in the north-eastern part of The Netherlands. In 1993, there were 3888 men and women, 57 years and older, who were without prevalent heart disease. During the 5-year follow-up period, 287 cases of incident heart disease (acute myocardial infarction and/or congestive heart failure) were registered (7%). Persons with a low socio-economic status had higher risks of heart disease (RR = 1.45 (95% CI: 1.06 - 1.99)) compared with their high status counterparts. On average, 4 percent of the socio-economic differences were accounted for by the classical coronary risk factors (e.g. smoking, hypertension) compared with 30 percent by the control beliefs. The contribution of the latter was largely independent of the former. Our findings support the hypothesis that socio-economic inequalities in heart disease-at least in middle-aged and older persons-may be based upon differences in control beliefs, more than upon differences in smoking rates and other classical risk factors.

Objective: This study examined the association between socioeconomic status and mobility decline and whether this could be explained by disease severity and comorbidity in four different chronic disease groups (asthma/COPD, heart disease, diabetes mellitus, and low back pain). It is not clear, whether the adverse course of physical functioning in persons with a low socioeconomic status can be explained by a higher prevalence of more severe disease or comorbidity in these persons., Design: Dutch GLOBE study: prospective cohort study., Setting: Region of Eindhoven (south east of the Netherlands)., Participants: 1384 persons suffering from at least one of the four chronic diseases were selected. The number of respondents in each group was: asthma/COPD 465, heart disease 788, diabetes mellitus 137, and low back pain 707. There were 580 respondents who suffered from more than one condition., Main Results: Odds ratios of mobility decline between 1991 and 1997, adjusted for age, sex, marital status, and baseline mobility, were significantly higher in low socioeconomic groups in comparison with high socioeconomic groups. Only very little of this association could be explained by the higher disease severity and comorbidity in these patients. Findings were similar in patients with asthma/COPD, heart disease, diabetes mellitus, and chronic low back pain., Conclusion: These findings indicate that to reduce physical disabilities and particularly the socioeconomic differences therein, it may not be sufficient to solely intervene upon the risks of severe disease and comorbidities.

Little is known of the biochemical processes of cognitive decline during 'healthy' aging. Biological markers in body fluids, such as blood, could provide insight in those processes. In the present studies serum concentrations of different markers have been correlated to cognitive functioning of cognitively healthy aging individuals over a period of six years (mean age 57 years, SD 11, n = 93). Markers were related to mechanisms known to be involved in Alzheimer's disease, including inflammation, cholesterol homeostasis and homocysteine homeostasis. Domains of cognitive function addressed were cognitive speed (Letter-Digit Coding test), attention and information processing (Stroop test), and memory (Word Learning test: Total Words and Delayed Recall). Baseline concentrations of haptoglobine, homocysteine, lathosterol and lanosterol were negatively correlated with cognitive functioning on the Stroop test over the whole follow-up period of six years. Concentrations of all markers, i.e. haptoglobine, C-reactive protein, homocysteine, lathosterol and lanosterol, were also negatively correlated with functioning on the Word Learning test (Delayed Recall and for some markers also with the Total Words) over the whole six-years follow-up period. In conclusion, concentrations of serum markers related to inflammation, homocysteine and cholesterol homeostasis are not only associated with Alzheimer's disease, but also with cognitive functioning in the cognitively healthy aging population.

Little is known about whether persons with mentally demanding jobs are protected against cognitive impairment and whether this association is independent of intellectual abilities and other confounders. Longitudinal data from the Maastricht Aging Study (MAAS) were used to examine this association. After the 1993-1995 baseline examination, there was a first 3-year follow-up examination (1996-1998) among 630 men and women, aged 50 to 80, who exhibited no cognitive impairment at baseline. Persons with mentally demanding jobs had lower risks of developing cognitive impairment during follow-up (36 cases), compared with persons without such jobs (odds ratio = 0.79; 95% confidence interval: 0.65-0.96). About 1.5% of the persons with high mental work demands developed impairment compared to 4% of the persons with few work demands. The protective effect was independent of intellectual abilities and other confounders. Our findings provide evidence that continued and potentially modifiable mental stimulation during adult life may protect men and women against cognitive impairment.

In a cross-sectional study, Jorm and colleagues (1993. Personality and Individual Differences, 15, 721-723) found that neuroticism was related to poorer cognitive performance in the elderly. The present study was initiated to expand their findings using both cross-sectional and longitudinal data from the Maastricht Aging Study. In contrast to the findings of Jorm and coworkers, neuroticism was not associated with either current cognitive performance or cognitive decline over a period of 3 years.

The present prospective study investigated whether elevated total serum homocysteine concentration is a risk factor for cognitive decline. The outcomes were compared to the possible relation between cognition and vitamin B12 or folic acid. Cognitive performance of 144 normal aging individuals (aged 30-80 years) was tested at baseline and after six years of follow-up. Domains of cognitive function addressed were cognitive speed (Letter-Digit Coding test), attention and information processing (Stroop test) and verbal learning and memory (Word Learning Test Total; Delayed Recall). Serum concentrations of homocysteine, folic acid and vitamin B12 were determined. Serum concentrations of homocysteine correlated negatively with cognitive performance on the Word Learning tests at baseline, independent of age, sex, education level or folic acid concentration. Homocysteine concentration at baseline correlated negatively with cognitive performance on the Stroop and Word Learning tests during the whole six-year follow-up period. The folic acid concentration correlated to the Delayed Recall test at baseline only and no correlations were observed for vitamin B12. Thus, while a relation between vitamin B12 or folic acid and cognition was almost absent, elevated homocysteine concentrations were associated with prolonged lower cognitive performance in this normal aging population.

Some studies have shown that cognitive function is positively affected by an engaged and active lifestyle. However, a recent study found evidence for an opposite causal direction, i.e., persons with good cognitive function more often start to engage in leisure-time activities. Here, we longitudinally examine the causal direction of the association between an engaged lifestyle and cognitive function in middle and old-aged Dutch men and women. The participants in the prospective cohort study "Maastricht Aging Study" (MAAS) were recruited from a register of 15 family practices in the South of the Netherlands. There were 830 non-demented men and women, aged 49 to 81 in 1993-1995 (baseline phase). They were re-examined three years later (follow-up phase). During both phases, all persons reported on their participation in mental, social, and physical activities. Six separate neuropsychological tests, including the Mini-Mental State Examination, were used to define cognitive function at baseline and follow-up. All three activities measured were negatively related to cognitive decline between both phases. Effects were moderate, but consistent. Persons participating in all three activities were particularly protected against longitudinal decline. Furthermore, persons with the best baseline cognitive performance were more likely to increase their number of activities during follow-up compared with persons with the poorest scores. In summary, an engaged lifestyle and cognitive function mutually influence each other in middle and old aged, non-demented persons. This reciprocal association is characterized by simultaneous positive effects of leisure-time activities and good cognitive function on cognitive function and leisure-time activities, respectively. This reciprocal association may create a self-reinforcing, beneficial or adverse life-course in middle and old age.

Background: The aim was to study hostility as a factor intermediate in the association between educational level and health., Methods: 1997 cross-sectional data from the Dutch GLOBE study (1675 men and 1819 women) was used. The analyses distinguishes between direct effects of hostility on health, and indirect effects, which are through health-related behaviours. The latter indicates that hostile people may be at risk of adverse health, because they engage in unhealthy behaviours. Data were analysed with logistic regression techniques., Results: Among men and women, the odds of less than good health was higher in lower educational groups. A substantial part of the educational gradient in health could be ascribed to the intermediate effects of hostility. Among both men and women, the direct effects of hostility were more important than indirect effects., Conclusion: Results suggest that interventions should be aimed at the prevention of the development of hostility. Additionally, interventions aimed at the reduction of health damaging behaviours among adults may lead to a reduction of socio-economic inequalities in health.

Background: Although biological sleep criteria seem to be associated with cognitive changes in older people, it is not clear if subjective sleep parameters are related to cognitive decline in later life., Objectives: The aim of this study was to determine whether subjective sleep complaints in a population-based sample of 838 middle aged and older adults (>or= 50 years) predicted cognitive decline over a period of 3 years., Methods: Sleep complaints at baseline, assessed with the subscale Sleep Problems of the Symptoms Checklist-90, were used as a predictor variable. Cognitive performance at follow-up, measured with the Mini Mental Status Examination, was employed as a dependent variable., Results: Controlling for the effects of age, gender, length of follow-up interval, systemic diseases, and cognitive function at baseline, subjective sleep complaints were negatively associated with cognitive performance at follow-up., Conclusion: Subjective sleep complaints predict cognitive decline in middle aged and older adults. Mechanisms behind the effect of subjective sleep complaints on cognitive performance are discussed., (Copyright 2002 John Wiley & Sons, Ltd.)

In a cross-sectional analysis of 818 healthy older individuals (aged 50 to 81 years), head size was found to be related to performance on tests measuring intelligence, global cognitive functioning, and speed of information processing, but not memory. These relations were not confounded by educational level, socioeconomic background, or height. Large head/brain size may protect elderly people against cognitive deterioration, supporting a reserve hypothesis of brain aging.

This study sought to determine the contribution of neighborhood socioeconomic status to all-cause mortality and to explore its correlates. As part of the longitudinal "Gezondheid en LevensOmstandigheden Bevolking en omstreken" (GLOBE) study in the Netherlands, 8,506 randomly selected men and women aged 15-74 years from 86 neighborhoods in the city of Eindhoven reported on their socioeconomic status in the 1991 baseline survey. During the 6-year follow-up, 487 persons died. Neighborhood socioeconomic status was derived from individual reports on socioeconomic status. Its effect on mortality was stringently controlled for four individual-level socioeconomic indicators. Persons living in a neighborhood with a high percentage of unemployed/disabled or poor persons had a higher mortality risk than did those living in a neighborhood with a low percentage of unemployed/disabled or poor persons. This was independent of individual socioeconomic characteristics, including individual unemployment/disability or reports of severe financial problems. Educational and occupational neighborhood indicators were similarly, but less strongly, related to mortality. The prevalence of poor housing conditions, social disintegration, and unhealthy psychologic profiles and behaviors was higher in neighborhoods with a low socioeconomic status. Contextual effects of socioeconomic status may thus be due to one or more of these specific circumstances. The findings indicate potential public health benefits of modifying socioeconomic characteristics of areas.

This study investigated the effects of the Job Demand-Control (JD-C) Model and the Effort-Reward Imbalance (ERI) Model on employee well-being. A cross-sectional survey was conducted comprising a large representative sample of 11,636 employed Dutch men and women. Logistic regression analyses were used. Controlling for job sector, demographic characteristics (including educational level) and managerial position, employees reporting high job demands (i.e. psychological and physical demands) and low job control had elevated risks of emotional exhaustion, psychosomatic and physical health complaints and job dissatisfaction (odds ratios ranged from 2.89 to 10.94). Odds ratios were generally higher in employees reporting both high (psychological and physical) efforts and low rewards (i.e. poor salary, job insecurity and low work support): they ranged from 3.23 to 15.43. Furthermore, overcommitted people had higher risks of poor well-being due to a high effort-low reward mismatch (ORs: 3.57-20.81) than their less committed counterparts (ORs: 3.01-12.71). Finally, high efforts and low occupational rewards were stronger predictors of poor well-being than low job control when both job stress models were simultaneously adjusted. In conclusion, our findings show independent cumulative effects of both the JD-C Model and the ERI Model on employee well-being and are not significantly different in men and women as well as in young and old people. In particular, high (psychological and physical) efforts and low rewards adversely affected employee well-being. Preliminary findings also indicate excess risks of poor well-being in overcommitted persons suffering from high cost--low gain conditions at work.

This study examined the role of several personal characteristics in the association between low job control and coronary heart disease among male and female British civil servants. The logistic regression analyses were based on a prospective cohort study (Whitehall II), comprising 6,895 men and 3,413 women, age 35-55 years. Men and women with low job control at baseline had 1.5 to 1.8 higher risks of new heart disease during the 5.3-year follow-up. Psychological attributes, such as hostility, negative affectivity, minor psychiatric disorder, and coping, affected this association very little. The personal characteristics were not confounders, intermediate factors, or effect modifiers. Hence, increasing job control could, in principle, lower risks of heart disease for all employees.

Adolescents' views of communication with their parents are examined in relation to measures of family satisfaction, adolescent decision-making and disagreement with parents (Study I), and to measures of self-esteem, well-being and coping (Study II). The results provide some support for the psychometric qualities of the Parent-Adolescent Communication Scale (PACS) and suggest that good family communication is associated with satisfaction with the family and with lack of disagreement between adolescents and parents. They also indicate a positive association between family communication and adolescent self-esteem, certain aspects of adolescent well-being and type of coping strategy employed., (Copyright 1998 The Association for Professionals in Services for Adolescents.)

The kinetics and specificity of reductive acylation of lipoyl domains derived from Azotobacter vinelandii 2-oxo-acid dehydrogenase complexes, catalysed by A. vinelandii and Escherichia coli complexes, have been investigated. With the wild-type pyruvate dehydrogenase complex from A. vinelandii the rate of reductive acetylation and deacetylation was studied by rapid mixing methods. The rate of reductive acetylation, 126 s(-1), corresponds well with the turnover rate derived from steady-state measurements. Deacetylation was rapid and specific for coenzyme A. No deacetylation was observed with reduced or oxidised lipoamide or with dithiothreitol. The rate of reductive acetylation of complex-bound lipoyl domains by pyruvate dehydrogenase (E1p) is at least 60 times higher than of free lipoyl domains under comparable conditions. This gain in catalytic rate indicates a large diffusion limitation of lipoyl domains when attached via the flexible linker segments to the complex, and illustrates the efficiency of substrate channeling in the multienzyme complex. The 2-oxo-acid dehydrogenases exhibit specificity for lipoyl domains in the reductive acylation reaction. The A. vinelandii lipoyl domain derived from the pyruvate dehydrogenase complex is a good substrate for A. vinelandii E1p, but not for A. vinelandii 2-oxoglutarate dehydrogenase (E1o), and vice versa. The A. vinelandii lipoyl domain of the pyruvate dehydrogenase complex is also, although at a lower rate, reductively acetylated by E. coli E1p and reductively succinylated by E. coli E1o. Likewise, the A. vinelandii lipoyl domain derived from the 2-oxoglutarate dehydrogenase complex is recognised by E. coli E1o, but not by E. coli E1p. This suggests that common determinants of the lipoyl domains exist that are responsible for recognition by the E1 components. On the basis of the observed specificity and lipoyl domain sequences and structures, an exposed loop of the A. vinelandii 2-oxoglutarate dehydrogenase complex lipoyl domain was subjected to mutagenesis. Although the reductive acylation experiments of mutants of the lipoyl domain indicate the importance of this loop for recognition, it is probably not the single determinant for specificity.

Two different Dutch data-sets were used to examine trends in the association between socio-economic characteristics and the risk of heart disease. Data of the Dutch Quality of Life Surveys allowed the examination of trends in the association between educational level and self-reported heart disease during the period 1974-1993. For both the general Dutch population and the subpopulation of men aged 40 years and older, we found an inverse gradient during the whole period. The gradient climaxed at 1980-1983, and narrowed afterwards. Furthermore, ecological analyses, relating regional mean personal incomes to regional directly standardised mortality rates of coronary heart diseases (CHD) and all heart diseases, showed similar patterns of social differentials. The findings suggest that, in the Netherlands, there is a narrowing gradient of the association between socio-economic characteristics and heart disease in the late eighties and early nineties.

Confirmatory factor analyses were done in an attempt to replicate the factor structure of the Aggression Questionnaire constructed by Buss and Perry (1992) [Journal of Personality and Social Psychology, 63, 452-459] in a Dutch sample. The findings indicated that the Buss and Perry 4-factor model provided a poor fit to the full 29-item questionnaire. Although generally confirming the 4-factor structure, subsequent analyses revealed that a better fit was obtained by omitting 3 items (1 Verbal Aggression and 2 Hostility items). In general, the present findings are rather similar to previous research and emphasize the importance of assessing not only overall aggression but also its separate components.

In a retrospective study, 154 embolectomies in 135 patients with acute arterial occlusion were reviewed and the value of intraoperative arteriography studied. Included in the study were 69 embolectomies of the femoro-popliteal artery in 64 patients, and in 40 (58%) intra-operative arteriography was performed. Of these, 20 were done because of difficulty in passing the Fogarty catheter and/or absent backflow and 20 as a routine procedure where there was easy passage of the catheter and good backflow. In 29 embolectomies (42%) intra-operative arteriography was not performed because some surgeons, doubting the benefit of routine arteriography, did not use it. In 23 cases (58%) intra-operative arteriography led to an extension of the operation. Six out of 20 routine arteriograms (30%) showed incomplete clearance of the arterial tree, resulting in further embolectomy. The amputation rate was 17%, however in the group where routine arteriography was performed it was zero and significantly less than in the non-arteriogram group (23%). The use of intra-operative arteriography in arterial embolectomy surgery is recommended.

Three methods for the determination of inorganic phosphorus were compared in order to evaluate the frequency of falsely high concentrations of inorganic phosphorus in 102 sera containing monoclonal immunoglobulins. The results for the three methods using neat sera were compared with those obtained from protein-free filtrates of the same sera. For the neat sera erroneously high results were encountered with the molybdate method in about 10% (11/102) of the cases. In contrast neither the enzymatic method nor the modified molybdate method gave erroneous results. The presence and magnitude of error of the molybdate method bore no relationship to the type or the concentration of the monoclonal immunoglobulins. The precipitation of monoclonal immunoglobulins by the strongly acidic molybdate reagent, leading to erroneous results, can not always be prevented by the addition of a detergent. Nor can the problem be solved by a simple two- or threefold dilution.

In these studies vasogenic brain edema has been induced by implantation of rat glioma cells RGI 2.2 into BD-IX rats while cytotoxic edema pas produced by permanent regional ischemia in the mongolian gerbil. In the gerbil sodium concentration was raised from 201 meq/kg d.w. (dry weight) [p/b (peak/background) = 0] to 269 meq/kg d.w. (p/b = 0.25; 2 hours) and 651 meq/kg d.w. [p/b = 0.71; 24 hours), whereas potassium concentration decreased from 373 meq/kg d.w. (p/b = 1.69) to 337 meq/kg d.w. (p/b = 1.65) and 152 meq/kg d.w. (p/b = 0.53). In the rat tumor sodium and potassium concentrations were 279 meq/kg d.w. (p/b = 0.44) and 510 meq/kg d.w. (p/b = 1.94). Non-tumorous tissue contained 237 meq/kg d.w. (p/b = 0) and 517 meq/kg d.w. (p/b = 1.98). In addition X-ray microanalysis could show that chlorine behaves like sodium, whereas the concentration of phosphorus and sulphur remains nearly constant. X-ray microanalysis in this case proved to be useful in the localization and quantification of different elements. The main disadvantage, however, is the reduced sensitivity for light elements, e.g. sodium, which cannot be determined in normal brain.

Sedimentation analysis and light-scattering studies indicate that the aggregation state of the pyruvate dehydrogenase complex of Azotobacter vinelandii in 50 mM potassium phosphate (pH 7.0) can be described in terms of a monomer-dimer equilibrium with a dissociation constant of 6.8 microM. The apparent molecular mass of the monomeric particle is 750 000-850 000 Da. The equilibrium is shifted to the monomeric species when pressure is applied on the system. Pressure-jump experiments yielded a relaxation time of about 70 ms. In the presence of 3% poly(ethylene glycol) 6000 and 10 mM MgCl2, further association takes place to a system that can be described in terms of dimer-tetramer-octamer equilibria. Upon applying a pressure of 80 MPa to this system these equilibria are shifted to the dimeric state but some monomer formation cannot be excluded. Release of pressure shows that the relaxation time of the dimer-tetramer equilibrium is less than 5 s, that of tetramer-octamer equilibrium is of the order of minutes. The isolated E2 component has a molecular mass of 2 000 000 +/- 100 000 Da; and thus consists of about 30 E2 peptide chains. Electron micrographs are similar to those of the E2 component of the Escherichia coli complex, which were interpreted as cubic structures with an octagonal symmetry. Upon addition of E1 to the pure E2 component, changes in the assembly occur and mixtures of large (E. coli-like, 22-45 S) and small (A. vinelandii-like, 11-18 S) subcomplexes are obtained. The two forms of the subcomplexes are in slow equilibrium (relaxation time 10-30 min). It is proposed that the E2 tetramer of the intact pyruvate dehydrogenase complex of A. vinelandii is represented by the corner structures of the isolated E2 component.

An improved purification procedure of the pyruvate dehydrogenase complex of Azotobacter vinelandii is described. This procedure minimizes losses of components and results in the isolation of the pure complex with a specific activity of 15-19 U/mg and an overall yield of 40%. The chain ratio of the three components was determined by covalent modification of the lysine residues with trinitrobenzene sulfonic acid, followed by separation of the components on sodium dodecyl sulfate gels. These determinations yielded an average chain ratio of 1.3:1:0.5 for E1:E2:E3 respectively. Based on E2 this corresponds with a minimum molecular mass of approximately 216 kDa. Because the molecular mass of the complex has been determined previously to be 800 +/- 50 kDa, it is concluded that the complex as isolated from A. vinelandii is based on a tetramer of E2 chains. The complex can be resolved into its individual components, which can be recombined to yield a fully active complex. Titration of E2E3 subcomplexes with E1 resulted in maximum complex activity at an E1/E2 ratio of 1.5-1.6. Similar titrations of E1E2 subcomplexes with E3 resulted in maximum activity at an E3/E2 ratio of 0.45-0.55. From these experiments it is concluded that the complex has maximum activity with a composition of three E1 dimers, one E2 tetramer and one E3 dimer. With excess of either E1 or E3 a decrease in activity is observed which indicates competition between these components for binding sites on E2. As shown before [Bosma, H.J., de Kok, A., Markwijk, B.W., and Veeger, C. (1984) Eur. J. Biochem. 140, 273-280], the isolated E2 component is composed of 32 peptide chains of 66 kDa each. Upon addition of E1 or E3, E2 dissociated into tetramers. Dissociation is complete upon the addition of four E1 dimers of four E3 dimers per E2 tetramer. Addition of E1 to saturated E2E3 subcomplex or E3 to saturated E1E2 subcomplex did not result in extra binding but rather in displacement of bound E3 or E1 respectively. It is therefore concluded that the binding sites of E1 and E3 to the E2 chains are either identical or so closely spaced that steric hindrance prevents simultaneous binding of both components. A model is presented based on the cubic structure of the isolated E2 component. In this model the 32 E2 peptide chains are arranged in tetramers in the corners of the cube. This model is discussed in connection with the existing model for the Escherichia coli complex.