Woody plant richness and NDVI response to drought events in Catalonian (northeastern Spain) forests

The role of species diversity on ecosystem resistance in the face of strong environmental fluctuations has been addressed from both theoretical and experimental viewpoints to reveal a variety of positive and negative relationships. Here we explore empirically the relationship between the richness of forest woody species and canopy resistance to extreme drought episodes. We compare richness data from an extensive forest inventory to a temporal series of satellite imagery that estimated drought impact on forest canopy as NDVI (normalized difference vegetation index) anomalies of the dry summer in 2003 in relation to records of previous years. We considered five different types of forests that are representative of the main climatic and altitudinal gradients of the region, ranging from lowland Mediterranean to mountain boreal-temperate climates. The observed relationship differed among forest types and interacted with the climate, summarised by the Thorntwaite index. In Mediterranean Pinus halepensis forests, NDVI decreased during the drought. This decrease was stronger in forests with lower richness. In Mediterranean evergreen forests of Quercus ilex, drought did not result in an overall NDVI loss, but lower NDVI values were observed in drier localities with lower richness, and in more moist localities with higher number of species. In mountain Pinus sylvestris forests NDVI decreased, mostly due to the drought impact on drier localities, while no relation to species richness was observed. In moist Fagus sylvatica forests, NDVI only decreased in plots with high richness. No effect of drought was observed in the high mountain Pinus uncinata forests. Our results show that a shift on the diversity-stability relationship appears across the regional, climatic gradient. A positive relationship appears in drier localities, supporting a null model where the probability of finding a species able to cope with drier conditions increases with the number of species. However, in more moist localities we hypothesize that the proportion of drought-sensitive species would increase in richer localities, due to a higher likelihood of co-occurrence of species that share moist climatic requirements. The study points to the convenience of considering the causes of disturbance in relation to current environmental gradients and historical environmental constraints on the community.

Thermal diagnostics front-end electronics for LISA Pathfinder

Precision temperature measurements are required in the LTP, the LISA technology package, for various diagnostics objectives. In this article, we describe in detail the front-end electronics design and the associated temperature sensors to achieve the LTP requirements: noise equivalent temperature of 10 microK Hz(-12) in the frequency range from 1 to 30 mHz at room temperature. We designed an ac Wheatstone bridge and a subsequent digital demodulation to minimize 1/f noise. We show experimental results where the required sensitivity in the measurement bandwidth is fulfilled.

Prevalence of dementia in a southern European population in two different time periods: the ZARADEMP Project

OBJECTIVE

To compare the prevalence of dementia in two different time periods and two different studies.

METHOD

Representative, random samples of the elderly (>65 years) in the Zaragoza Study or ZARADEMP-0 (n = 1080) completed the previous decade, and now in Wave I of the ZARADEMP Project or ZARADEMP-I (n = 3715) were interviewed. Standardized measures included the Geriatric Mental State and the History and Aetiology schedule. Cases of dementia were diagnosed according to DSM-IV criteria.

RESULTS

Adjusted, global prevalence of dementia has not varied significantly: it was 5.2% (95% CI = 3.9-6.6) in ZARADEMP-0 and 3.9% (95% CI = 3.3-4.5) in ZARADEMP-I (prevalence ratio = 0.75; 95% CI = 0.56-1.02). However, the prevalence in ZARADEMP-I was significantly lower among men, particularly in all age groups between 70 and 84 years.

CONCLUSION

Stability of the global prevalence of dementia in the elderly population has been documented. However, the decreased prevalence found in elderly men stimulated environmental hypotheses.

[Prevalence of vascular risk factors among Spanish populations aged 70 years and over, as reported in door-to-door studies on neurological diseases]

INTRODUCTION

The aim of this study was to re-analyze door-to-door studies on neurological diseases among the elderly, in which vascular risk factors (VRF) were studied, describing methodological characteristics and prevalence of VRF.

METHODS

The surveys were identified in two phases. They were aimed at ascertaining prevalence of stroke, dementias or Parkinsonisms and, at the time of individual screening, had collected data on at least three of the following VRF: arterial hypertension (AHT), smoking habit, diabetes mellitus and hypercholesterolemia. A questionnaire was drawn up to collect the data reported in each study, and a database was constructed. VRF prevalences were quantified and analyzed using logistic regression.

RESULTS

The total of the re-analyzed population was 12,510 persons aged 70 years and over, residents in seven geographic areas during the period 1994-2002. Information available on VRF was essentially self-reported. The prevalence of self-reported AHT was 25.7 % in men and 44.2 % in women, and that of measured AHT was 61 % and 71.9 %, respectively. Populations with arterial pressure obtained by direct measurement registered 138 higher risks (OR: 1.74; 95 % CI: 1.51-2.01, and OR: 1.48; 95% CI: 1.33-1.64). Reported prevalence of diabetes, hypercholesterolemia and smoking habit were 14.3 %, 23.3% and 8.5 %, respectively.

CONCLUSIONS

There was a high prevalence of VRF among the Spanish elderly population. However, its relationship with dementia, Parkinsonisms and cerebrovascular disease could not be studied due to the poor quality of the VRF data. The differences between measured and self-reported arterial pressure suggest the existence of undetected AHT and wide scope for prevention.

Spanish Perspective on Enlarging a Small Specialty: The National Research Network for Liaison Psychiatry and Psychosomatics

The Spanish Research Network in Liaison Psychiatry and Psychosomatics (REPEP) comprises 11 centers (nodes), and was one of the successful applicants in a very competitive call for a networking program for the National Institute of Health "Carlos III" project. This article describes its general objectives and strategic plans. Both qualitative and quantitative results support our statement that this "perspective" should help to enlarge what is presently a small specialty. Synergies in the network have been potentiated; an ambitious national study on depressive comorbidity in complex medical patients has been executed; and new research and training programs have been initiated.

Prevalent and incident depression in community-dwelling elderly persons with diabetes mellitus: results from the ZARADEMP project

AIMS/HYPOTHESIS

Although several studies have reported on the association between diabetes and depression, none have used both formal psychiatric criteria and a prospective, population-based design. Therefore, it remains unclear whether diabetes is a risk factor for the development of depression. Moreover, it is not clear if this effect is influenced by other chronic diseases and functional disabilities.

METHODS

A large (n=4,803) representative community-based study in Spanish elderly subjects (at least 55 years of age) was conducted. The presence of major depression was assessed by means of a standardised psychiatric diagnostic interview (Automated Geriatric Examination for Computer Assisted Taxonomy). Subjects underwent a baseline assessment and a follow-up assessment after 2 and 5 years to determine the incidence of depression.

RESULTS

At baseline 597 subjects (12.5%) were identified as having diabetes. Prevalence and incidence of depression in cases of diabetes were 15.4% and 16.5% respectively. Diabetes was associated with an increased risk of prevalent (odds ratio [OR]=1.47; 95% CI: 1.16-1.83) and incident (OR=1.40; 95% CI: 1.03-1.90) depression. Controlling for potential confounders did not essentially change these findings (prevalent depression: OR 1.41, 95% CI: 1.08-1.83; incident depression: OR 1.26, 95% CI: 0.90-1.77).

CONCLUSIONS/INTERPRETATION

In a large, representative prospective population-based sample using strict psychiatric criteria, we confirmed previous findings that diabetes is associated with an increased risk of depression. The effect on the incidence of depression suggests that diabetes may play a role in the development of depression in the elderly. The presence of comorbid medical diseases seems to decrease the effects of diabetes on the risk of prevalent depression, but to increase the risk of incident depression.

Photoelectron Spectroscopic Investigations of Chemical Bonding in Organically Stabilized PbS Nanocrystals

The surface structure of organically capped PbS nanocrystals using synchrotron radiation excited core-level photoelectron spectroscopy has been studied. The nanocrystallites prepared by methods of colloidal chemistry have average diameters of 3.1, 3.9, 4.6, and 7.6 nm with narrow size distributions and are stabilized either with oleic acid only or with a combination of trioctylphosphine and oleic acid as ligands. High resolution photoelectron spectroscopy measurements allowed the surface structure to be studied and in particular how the organic ligands bind to the surface of the PbS nanocrystals to be elucidated. The results indicate that the trioctylphosphine ligands passivate only the surface S sites while oleic acid ligands appear to bind mainly to Pb sites.

The effect of nanocrystal surface structure on the luminescence properties: Photoemission study of HF-etched InP nanocrystals

InP nanocrystals with narrow size distribution and mean particle diameter tunable from approximately 2 up to approximately 7 nm were synthesized via the dehalosilylation reaction between InCl3 and tris(trimethylsilyl)phosphine. Specific capping of the nanocrystal surface with a shell of organic ligands protects the nanocrystals from oxidation and provides solubility of the particles in various organic solvents. InP nanocrystals with enhanced photoluminescence (PL) efficiency were obtained from the initial nanocrystals by photoassisted etching of the nanocrystal surface with HF. The resulting PL quantum efficiency of InP nanocrystals dispersed in n-butanol is about three orders of magnitude higher when compared to the nonetched InP samples and approaches approximately 40% at room temperature. High-resolution photoelectron spectroscopy with the use of synchrotron radiation was applied to reveal the changes of the nanocrystal surface responsible for the dramatic improvement of the PL efficiency. The analysis of high-resolution P 2p core-level spectra confirmed significant changes of the nanocrystal surface structure induced by the postpreparative treatments and allowed us to propose the description of the etching mechanism. In the nonetched InP nanocrystals, some surface P atoms generate energy states located inside the band gap which provide nonradiative recombination pathways. Photoassisted treatment of InP nanocrystals with HF results in selective removal of these phosphorous atoms from the nanocrystal surface. The reconstructed surface of the etched InP nanocrystals is terminated mainly with In atoms and is efficiently passivated with tri-n-octylphosphine oxide ligands.

Effect of smoking on global cognitive function in nondemented elderly

BACKGROUND

Contrary to early case-control studies that suggested smoking protects against Alzheimer disease (AD), recent prospective studies have shown that elderly who smoke may be at increased risk for dementia.

OBJECTIVE

To examine prospectively the effect of smoking on cognition in nondemented elderly.

METHOD

In a multicenter cohort, the European Community Concerted Action Epidemiology of Dementia (EURODEM), including the Odense, Personnes Agées Quid (Paquid), Rotterdam, and Medical Research Council: Ageing in Liverpool Project-Health Aspects (MRC ALPHA) Studies, 17,610 persons aged 65 and over were screened and examined for dementia. After an average 2.3 years of follow-up, 11,003 nondemented participants were retested. Excluding incident dementia cases and those without baseline information on smoking gave an analytical sample of 9,209 persons. Average yearly decline in Mini-Mental State Examination (MMSE) score was compared among groups, adjusting for age, sex, baseline MMSE, education, type of residence, and history of myocardial infarction or stroke.

RESULTS

MMSE score of persons who never smoked on average declined 0.03 point/year. The adjusted decline of former smokers was 0.03 point greater and of current smokers 0.13 point greater than never smokers (p < 0.001). Higher rates of decline by smoking were found in men and women, persons with and without family history of dementia, and in three of four participating studies. Higher cigarette pack-year exposure was correlated with a significantly higher rate of decline.

CONCLUSION

Smoking may accelerate cognitive decline in nondemented elderly.

Mental disturbances and perceived complexity of nursing care in medical inpatients: results from a European study

AIMS AND OBJECTIVES

The relationship between mental disturbances - anxiety and depression, somatization and alcohol abuse - on admission to internal medicine units and perceived complexity of care as indicated by the nurse at discharge was studied. The goal was to study the utility of short screeners for mental disturbances to select patients for case-management on admission.

DESIGN

The study had a cohort design: patients were included on admission and followed through their hospital stay until discharge. The study was conducted within the framework of the European Biomed 1 Risk Factor study. RESEARCH METHODS AND INSTRUMENTS: In the first 3 days of admission the patients were interviewed by a trained health care professional, who scored the SCL-8D, a somatization questionnaire based on the Whiteley-7 and the CAGE. At discharge, nurses rated the complexity of the patient's care.

RESULTS

Patients with high scores on anxiety and depression (SCL-8D) and on somatization received higher ratings on perceived nursing complexity than those with low scores, with and without control for age, severity of illness and chronicity. The actual nursing intensity and medical care utilization, as measured daily by means of a checklist, could not explain these relations. No differences were found between patients with high or low scores on alcohol abuse.

CONCLUSIONS

The study shows a potential use of screeners for mental disturbances to detect patients for whom nurses might need additional help. However, mental disturbance is not the sole criterion: functional status and other variables that predict medical and nursing care utilization should be included in a screening strategy for case-management programmes.

Religion as a cross-cultural determinant of depression in elderly Europeans: results from the EURODEP collaboration

BACKGROUND

The protective effects of religion against late life depression may depend on the broader sociocultural environment. This paper examines whether the prevailing religious climate is related to cross-cultural differences of depression in elderly Europeans.

METHODS

Two approaches were employed, using data from the EURODEP collaboration. First, associations were studied between church-attendance, religious denomination and depression at the syndrome level for six EURODEP study centres (five countries, N = 8398). Secondly, ecological associations were computed by multi-level analysis between national estimates of religious climate, derived from the European Value Survey and depressive symptoms, for the pooled dataset of 13 EURODEP study centres (11 countries, N = 17,739).

RESULTS

In the first study, depression rates were lower among regular church-attenders, most prominently among Roman Catholics. In the second study, fewer depressive symptoms were found among the female elderly in countries, generally Roman Catholic, with high rates of regular church-attendance. Higher levels of depressive symptoms were found among the male elderly in Protestant countries.

CONCLUSIONS

Religious practice is associated with less depression in elderly Europeans, both on the individual and the national level. Religious practice, especially when it is embedded within a traditional value-orientation, may facilitate coping with adversity in later life.

Referral pattern of neurological patients to psychiatric Consultation-Liaison Services in 33 European hospitals

The referral pattern of neurological patients to 33 European psychiatric consultation-liaison (C-L) services in the general hospital was examined. Analyses were conducted on the ECLW CS data set, which consists of 14,717 psychiatric C-L referrals made in 56 European hospitals during 1991. Psychiatric referrals of patients admitted to neurological wards were compared to referrals from other wards. Information was obtained from 33 neurological wards, consisting of 34,506 neurological admissions. Of these admissions, 839 were referred to C-L psychiatry. The median consult rate among the hospitals was 1.8%. Compared to other hospital wards, patients referred from neurology were more frequently diagnosed as suffering from somatoform (P<.01) and dissociative disorders (P<.01), and less from substance abuse (P<.01) and delirium (P<.01). Referral to C-L psychiatry from neurological wards is characterized by an underestimation of psychiatric co-morbidity and a late detection, comparable to other medical specialties. An appeal is made for a standardized referral procedure including admission screening method, detecting patients at risk for nonstandard care during their hospital admission.

COMPRI—An Instrument to Detect Patients With Complex Care Needs: Results From a European Study

The authors developed a screening instrument to detect patients in need of complex care coordination at admission to a general hospital. On the basis of a series of risk factors for care complexity, the authors constructed a short, care complexity prediction instrument (COMPRI) and assessed its qualities. The COMPRI is an easily administered screening instrument that detects patients at risk for complex care needs for whom care coordination is indicated. COMPRI's predictive power exceeds all currently available case-mix instruments.

Risk Factors for Complex Care Needs in General Medical Inpatients: Results From a European Study

The authors linked admission risk factors to a series of indicators for complex care delivery to enable detection of patients in need of care coordination at the moment of admission to the general hospital. The authors found 13 risk factors to be predictive of more than one indicator of care complexity. An admission risk screening procedure to detect patients in need of care coordination should focus on these risk factors and should include predictions made by doctors and nurses at admission and information collected from the patient and the medical chart.

Care Complexity in the General Hospital Results From a European Study

There is increasing pressure to effectively treat patients with complex care needs from the moment of admission to the general hospital. In this study, the authors developed a measurement strategy for hospital-based care complexity. The authors' four-factor model describes the interrelations between complexity indicators, highlighting differences between length of stay (LOS), objective complexity (such as medications or consultations), complexity ratings by the nurse, and complexity ratings by the doctor. Their findings illustrate limitations in the use of LOS as a sole indicator for care complexity. The authors show how objective and subjective complexity indicators can be used for early and valid detection of patients needing interdisciplinary care.

Consultation-Liaison psychiatric service delivery: results from a European study

The reported findings of the European Consultation-Liaison Workgroup (ECLW) Collaborative Study describe consultation-liaison service delivery by 56 services from 11 European countries aggregated on a C-L service level. During the period of 1 year (1991), the participants applied a standardized, reliability tested method of patient data collection, and data were collected describing pertinent characteristics of the hospital, the C-L service, and the participating consultants. The consultation rate of 1% (median; 1.4% mean) underscores the discrepancy between epidemiology and the services delivered. The core function of C-L services in general hospitals is a quick, comprehensive emergency psychiatric function. Reasons to see patients were the following. deliberate self-harm (17%), substance abuse (7.2%), current psychiatric symptoms (38.6%), and unexplained physical complaints (18.6%) (all means). A significant number of patients are old and seriously ill. Mood disorders and organic mental disorders are most predominant (17.7%). Somatoform and dissociative disorders together constitute 7.5%. C-L services in European countries are mainly emergency psychiatric services and perform an important bridge function between primary, general health, and mental health care.

[Multinational European project and multicenter Spanish study of quality improvement of assistance on consultation-liaison psychiatry in general hospital: clinical profile in Spain]

BACKGROUND

In the frame of the European study on quality assurance in consultation liaison psychiatry and psychosomatics (supported by the BIOMED 1 program), the clinical <<process>> of consultation-liaison psychiatry units pertaining to six Spanish general hospitals is analyzed.

PATIENTS AND METHOD

A sample of 3. 608 consecutive patients referred to the consultation-liaison psychiatry units of five public general hospitals (Clínico of Zaragoza, Clínico of Barcelona, General of Alicante, Ramón y Cajal of Madrid, Princesa of Madrid) and one private gynecological hospital (Dexeus of Barcelona) was studied. The data were recorded with a standardized instrument (CL-BDoK-P), validated in a previous study.

RESULTS

Consult request took place 10.6 days (on average) after the patients admission (<<lagtime 1>>), half the requests were urgent, and psychiatric consultants examined the patients 1.9 days (on average) after the request (<<lagtime 2>>). The most frequent reasons for referral were current psychiatric symptoms (50.3%), unexplained physical symptoms (15.2%), substance abuse (9.2%), psychiatric history (8.5%), suicide risk (6%) and coping with illness (5.8%). The main referral services were internal medicine (17.5%), traumatology (7.5%) and general surgery (7.3%). An important clinical activity is documented in patients frequently considered to be <<complex>>, with broad spectrum diagnostic and interventions processes and both in-hospital and out-patient follow-up. However, some problems were also detected in the clinical <<process>>.

CONCLUSIONS

The results outline the clinical importance of Spanish consultation-liaison psychiatry in the general hospital, but the possibility of improving its efficiency through the implementation of integrative models, organizational changes and modern models of <<quality assurance>> is also emphasized.

Study on COgnition and Prognosis in the Elderly (SCOPE): baseline characteristics

The Study on COgnition and Prognosis in the Elderly (SCOPE) is a multi-centre, prospective, randomized, double-blind, parallel-group study. The primary objective of SCOPE is to assess the effect of the angiotensin II type 1 (AT1) receptor blocker, candesartan cilexetil 8-16 mg once daily, on major cardiovascular events in elderly patients (70-89 years of age) with mild hypertension (DBP 90-99 and/or SBP 160-179 mmHg). The secondary objectives of the study are to test the hypothesis that antihypertensive therapy can prevent cognitive decline (as measured by the Mini Mental State Examination, MMSE) and dementia, and to assess the effect of therapy on total mortality, myocardial infarction (MI), stroke, renal function, and hospitalization. A total of 4964 patients from 15 participating countries were recruited during the randomization phase of SCOPE, exceeding the target population of 4000. The mean age of the patients at enrolment was 76 years, the ratio of male to female patients was approximately 1:2, and 52% of patients were already being treated with an antihypertensive agent at enrolment. The majority of patients (88%) were educated to at least primary school level. At randomization, mean sitting blood pressure values were SBP 166 mmHg and DBP 90 mmHg, and the mean MMSE score was 28. Previous cardiovascular disease in the study population included myocardial infarction (4%), stroke (4%) and atrial fibrillation (4%). Men, more often than women, had a history of previous MI, stroke and atrial fibrillation. A greater percentage of men were smokers (13% vs 6% in women) and had attended university (11% vs 3% of women). Of the randomized patients, 21% were 80 years of age. In this age group smoking was less common (4% vs 10% for 70-79-year-olds) and fewer had attended university (4% vs 7% for 70-79-year-olds). The incidence of MI was similar in both age groups. However, stroke and atrial fibrillation had occurred approximately twice as frequently in the older patients. The patients' mean age at baseline was similar in the participating countries, and most countries showed the approximate 1:2 ratio for male to female patients. There was also little inter-country variation in terms of mean SBP, DBP or MMSE score. However, there was considerable regional variation in the percentage of patients on therapy prior to enrolment.

Prognosis with dementia in Europe: A collaborative study of population-based cohorts. Neurologic Diseases in the Elderly Research Group

The effect of dementia on time to death and institutionalization in elderly populations is of importance to resource planning, as well as to patients and their carers. The authors report a collaborative reanalysis of nine population-based studies conducted in Europe to compare dementia cases and noncases in risk of and time to death and to institutionalization. Prevalent and incident cases were more likely than noncases to reside in an institution at baseline and were more likely to enter institutional care. Prevalent cases also had over twice the risk of death compared to noncases and survival for men with dementia was consistently lower than that for women with dementia of the same age group.

Frequency of stroke in Europe: A collaborative study of population-based cohorts. ILSA Working Group and the Neurologic Diseases in the Elderly Research Group. Italian Longitudinal Study on Aging

The authors estimated stroke frequency in Europe using data from six population-based studies that were analyzed separately and also pooled. Overall, these surveys comprised 19,132 individuals age 55 years and older for the prevalence analyses, and 35,577 person-years for the incidence analyses. The overall prevalence of stroke, age- and sex-adjusted to the 1991 European population, was 4.84% (95% CI 4.47 to 5.21) in individuals age 65 to 84 years and 7.06% (95% CI 6.52 to 7.60) in those 75 years and older. Age- and sex-specific rates did not differ substantially across the studies. Incidence rates of first-ever stroke rose markedly with age, and the pooled results confirmed that incidence keeps increasing even at 90 years of age and older. The overall age- and sex-standardized incidence rates were 8.72 per 1000 person-years (95% CI 7.47 to 10.06) for individuals age 65 to 84 years, and 17.31 per 1000 person-years (95% CI 14.79 to 20.02) for those age 75 years and over.

Prevalence of dementia and major subtypes in Europe: A collaborative study of population-based cohorts. Neurologic Diseases in the Elderly Research Group

The last comparison of prevalence figures of dementia across European studies was 10 years ago. Using studies conducted in the 1990s, the authors compare the age- and sex-specific prevalence of dementia, AD, and vascular dementia (VaD) across European population-based studies of persons 65 years and older. Data from these studies were also pooled to obtain stable estimates of age- and sex-specific prevalence. A total of 2346 cases of mild to severe dementia were identified in 11 cohorts. Age-standardized prevalence was 6.4% for dementia (all causes), 4.4% for AD, and 1.6% for VaD. The prevalence of dementia increased continuously with age and was 0.8% in the group age 65 to 69 years and 28.5% at age 90 years and older. The corresponding figures for AD (53.7% of cases) were 0.6% and 22.2%, and for VaD (15.8% of cases), 0.3% and 5.2%. Variation of AD prevalence across studies was greatest for men. In the VaD subtype, a large variation across studies was observed, as well as a difference in prevalence between men and women that was age dependent. Dementia is more prevalent in women, and AD is the main contributor to the steep increase of prevalence with age.

Incidence of dementia and major subtypes in Europe: A collaborative study of population-based cohorts. Neurologic Diseases in the Elderly Research Group

The authors examined the association of incident dementia and subtypes with age, sex, and geographic area in Europe. Incidence data from eight population-based studies carried out in seven European countries were compared and pooled. The pooled data included 835 mild to severe dementia cases and 42,996 person-years of follow-up. In all studies a higher proportion of cases were diagnosed with AD (60 to 70% of all demented cases) than vascular dementia (VaD). The incidence of dementia and AD continued to increase with age up to age 85 years, after which rates increased in women but not men. There was a large variation in VaD incidence across studies. In the pooled analysis, the incidence rates increased with age without any substantial difference between men and women. Surprisingly, higher incidence rates of dementia and AD were found in the very old in northwest countries than in southern countries. This study confirms that AD is the most frequent dementing disorder in all ages, and that there is a higher incidence of dementia, specifically AD, in women than men among the very old. Finally, there may be regional differences in dementia incidence.

Prevalence of Parkinson's disease in Europe: A collaborative study of population-based cohorts. Neurologic Diseases in the Elderly Research Group

The results of seven population-based studies were examined separately and pooled to obtain age- and sex-specific estimates of the prevalence of PD. An in-person screening instrument and diagnostic clinical examination were used to detect potential PD cases. The overall prevalence (per 100 population) in persons 65 years of age and older was 1.8, with an increase from 0.6 for those age 65 to 69 years to 2.6 for those 85 to 89 years. There were no sex differences in prevalence of PD.

European consultation-liaison services and their user populations: the European Consultation-Liaison Workgroup Collaborative Study

The authors identified variations in the characteristics of patients referred to 56 consultation-liaison (C-L) services in 11 European countries. The authors found differences in the types of patients referred to the services, and there were significant differences between countries. The first difference lays in whether services saw patients for deliberate self-harm and for substance abuse. German psychosomatic C-L services saw virtually no such patients, although in other C-L services these patients constituted one-quarter to one-third of the patients referred. The second difference lays in the remaining group of referred patients. This group is best characterized by two dimensions. One describes the severity of psychopathology -- ranging from organic mental conditions to somatization. The other describes the clarity of the physical diagnosis -- ranging from patients referred by surgical wards to those referred by general medicine and neurology wards.

High-level expression of Escherichia coli and Bacillus subtilis thymidylate synthases

Procedures are described for the preparation of highly purified thymidylate synthases from Escherichia coli and Bacillus subtilis. The yields in each case are quite high with about 350 mg of pure protein obtained from 1 liter of cells. Basically all that is required to obtain pure enzyme is an induction step from a high-expression vector, followed by a DE-52 column elution. Both enzymes appeared to be fairly stable in that incubation at 43 degrees C for 10 min resulted in the loss of 50% of the E. coli thymidylate synthase activity, while 50 degrees C for 10 min was required to obtain the same effect with the B. subtilis enzyme. In the presence of the substrate, dUMP, each protein was stabilized further by 6 to 7 degrees C, which was increased to 9 to 10 degrees C on addition of dihydrofolate. It was shown also that the E. coli thymidylate synthase could be maintained at 4 degrees C for at least 4 months with little or no loss in activity provided that mercaptoethanol was not present. The presence of the latter led to a progressive loss in activity until little activity could be detected after 18 weeks, which was due, in part, to the formation of a disulfide bond with the active site cysteine. Addition of dithiothreitol restored the enzyme activity to its original state.

Education and the risk for Alzheimer's disease: sex makes a difference. EURODEM pooled analyses. EURODEM Incidence Research Group

The hypothesis that a low educational level increases the risk for Alzheimer's disease remains controversial. The authors studied the association of years of schooling with the risk for incident dementia and Alzheimer's disease by using pooled data from four European population-based follow-up studies. Dementia cases were identified in a two-stage procedure that included a detailed diagnostic assessment of screen-positive subjects. Dementia and Alzheimer's disease were diagnosed by using international research criteria. Educational level was categorized by years of schooling as low (< or =7), middle (8-11), or high (> or =12). Relative risks (95% confidence intervals) were estimated by using Poisson regression, adjusting for age, sex, study center, smoking status, and self-reported myocardial infarction and stroke. There were 493 (328) incident cases of dementia (Alzheimer's disease) and 28,061 (27,839) person-years of follow-up. Compared with women with a high level of education, those with low and middle levels of education had 4.3 (95% confidence interval: 1.5, 11.9) and 2.6 (95% confidence interval: 1.0, 7.1) times increased risks, respectively, for Alzheimer's disease. The risk estimates for men were close to 1.0. Finding an association of education with Alzheimer's disease for women only raises the possibility that unmeasured confounding explains the previously reported increased risk for Alzheimer's disease for persons with low levels of education.

European Consultation-Liaison Psychiatric Services: the ECLW Collaborative Study

OBJECTIVE

To describe the patterns of organization of consultation-liaison (C-L) services in 11 European countries in relation to hospital characteristics and national approaches to C-L psychiatry.

METHOD

Cross-sectional survey.

RESULTS

Services can best be described in terms of their size and seniority of their staff and whether or not they are multidisciplinary. Single-discipline services are based upon the standard medical consultant model, whereas those with multidisciplinary teams work in a way that is comparable with community mental health teams. German psychosomatic C-L services belonged to either model. National differences were found.

CONCLUSION

This first international study provides empirical evidence for the wide variation in the organization of C-L services. In view of the increasing numbers of patients with psychiatric disorder who are being treated in general hospitals and the changing patterns of medical care there are important implications for clarification and improvement of the role of C-L services.

[The assessment of working memory by Mini-Mental State Examination]

INTRODUCTION

Delayed recall items of the Mini-Mental State Examination (MMSE) and the Mini Cognitive Examination are based on a simultaneous processing of the storage of the material to be remembered while other test's items are executed. This function is probably mediated by the working memory (WM) system.

OBJECTIVE

A new protocol of WM assessment during the Mini Cognitive Examination application is presented.

PATIENTS AND METHODS

The standard Mini Cognitive Examination is modified with two new items of registration and recall. Criteria to introduce three new words in registration 2 and 3 is a complete recall of the three previous words. The score of the three recall trials, until a 27 points maximum, represents WM. A sample of 44 patients with probable Alzheimer's disease (AD), 19 with possible AD, 39 patients with cognitive impairment without dementia and 14 control subjects were evaluated.

RESULTS

Patients with probable AD and possible AD showed the minimum WM scores and the greatest percentage of words repetitions (WM 3.2 +/- 3.6 and 7 +/- 6, with 91 and 83% of repetitions, respectively); control subjects scored a WM of 22 +/- 6 with 14% of repetitions; patients with cognitive impairment without dementia scored a WM of 11 +/- 4 and 50% of repetitions.

CONCLUSIONS

We propose that delayed recall items of the MMSE and the Mini Cognitive Examination are an index of WM capacity. This new method reinforces the assessment of delayed recall during Mini Cognitive Examination or MMSE application, and can facilitate an early detection of anterograde amnesia.

Study on COgnition and Prognosis in the Elderly (SCOPE)

The Study on COgnition and Prognosis in the Elderly (SCOPE) is a multicentre, prospective, randomized, double-blind, parallel-group study designed to compare the effects of candesartan cilexetil and placebo in elderly patients with mild hypertension. The primary objective of the study is to assess the effect of candesartan cilexetil on major cardiovascular events. The secondary objectives of the study are to assess the effect of candesartan cilexetil on cognitive function and on total mortality, cardiovascular mortality, myocardial infarction, stroke, renal function, hospitalization, quality of life and health economics. Male and female patients aged between 70 and 89 years, with a sitting systolic blood pressure (SBP) of 160-179 mmHg and/or diastolic blood pressure (DBP) of 90-99 mmHg, and a Mini-Mental State Examination (MMSE) score of 24 or above, are eligible for the study. The overall target study population is 4000 patients, at least 1000 of whom are also to be assessed for quality of life and health economics data. After an open run-in period lasting 1-3 months, during which patients are assessed for eligibility and those who are already on antihypertensive therapy at enrolment are switched to hydrochlorothiazide 12.5 mg o.d., patients are randomized to receive either candesartan cilexetil 8 mg once daily (o.d.) or matching placebo o.d. At subsequent study visits, if SBP remains >160 mmHg, or has decreased by <10 mmHg since the randomization visit, or DBP is >85 mmHg, study treatment is doubled to candesartan cilexetil 16 mg o.d. or two placebo tablets o.d. Recruitment was completed in January 1999. At that time 4964 patients had been randomized. All randomized patients will be followed for an additional 2 years. If the event rate is lower than anticipated, the follow-up will be prolonged.

Gender differences in the incidence of AD and vascular dementia: The EURODEM Studies. EURODEM Incidence Research Group

OBJECTIVE

To study the difference in risk for dementing diseases between men and women.

BACKGROUND

Previous studies suggest women have a higher risk for dementia than men. However, these studies include small sample sizes, particularly in the older age groups, when the incidence of dementia is highest.

METHODS

Pooled analysis of four population-based prospective cohort studies was performed. The sample included persons 65 years and older, 528 incident cases of dementia, and 28,768 person-years of follow-up. Incident cases were identified in a two-stage procedure in which the total cohort was screened for cognitive impairment, and screen positives underwent detailed diagnostic assessment. Dementia and main subtypes of AD and vascular dementia were diagnosed according to internationally accepted guidelines. Sex- and age-specific incidence rates, and relative and cumulative risks for total dementia, AD, and vascular dementia were calculated using log linear analysis and Poisson regression.

RESULTS

There were significant gender differences in the incidence of AD after age 85 years. At 90 years of age, the rate was 81.7 (95% CI, 63.8 to 104.7) in women and 24.0 (95% CI, 10.3 to 55.6) in men. There were no gender differences in rates or risk for vascular dementia. The cumulative risk for 65-year-old women to develop AD at the age of 95 years was 0.22 compared with 0.09 for men. The cumulative risk for developing vascular dementia at the age of 95 years was similar for men and women (0.04).

CONCLUSION

Compared with men, women have an increased risk for AD. There are no gender differences in risk for vascular dementia.

Mortality and mental disorders in a Spanish elderly population

OBJECTIVE

To analyse the relationship between mental disorders and mortality rates in the elderly community of Zaragoza, Spain.

METHODS

Baseline, cross-sectional study (two-stage screening) of a representative, stratified sample (N=1080) of the elderly (65+ years) living in the community. Follow-up study (4.5 years).

INSTRUMENTS

Spanish versions of Geriatric Mental State, AGECAT computerized diagnostic program and Mini-Mental Status Examination.

RESULTS

Two hundred and sixteen subjects died during the follow-up period (global mortality rate 4.8% per year). Using a logistic regression model with sex, age, educational level, physical illness and AGECAT diagnoses as explanatory variables and alive/dead as response, the following odds ratios (95% confidence intervals in parentheses) were obtained (reference group: non-cases): 'subcases' 1.3 (0.9-2.0), 'organic' (dementia) 3.7 (2.0-6.7), global depression 3.0 (1.7-5.3), 'psychotic' depression (melancholic type) 3.7 (1.7-8. 4), 'neurotic' depression 2.7 (1.4-5.3) and 'neuroses' 0.8 (0.2-3.6). Both pure 'organic' and pure 'depressed' cases had higher mortality when compared with comorbidity cases.

CONCLUSION

There is a significant association between psychiatric morbidity and mortality in the elderly living in a Spanish community. Mortality risk in psychiatric cases are higher than previously reported in the literature.

[Revalidation and standardization of the cognition mini-exam (first Spanish version of the Mini-Mental Status Examination) in the general geriatric population]

BACKGROUND

The revalidation of the Mini Examen Cognoscitivo (MEC), first Spanish version (1978) of the Mini-Mental Status Examination (MMSE) and documentation of "population-based norms" should clarify the potential confusion induced by later versions of MMSE.

METHODS

CONTEXT

The Zaragoza Study on the prevalence of dementia and depression in a representative sample of the elderly community (N = 1,080).

INSTRUMENTS

MEC-35 and MEC-30 points, and validated, Spanish versions of Geriatric Mental State (GMS), History and Aetiology Schedule (HAS) and Social Status Schedule (SSS).

PROCEDURE

a) validation of MEC (standardized lay interviewers) against the gold standard of psychiatric diagnosis (DSM-III-R), two months later; b) "population-based norms" in the "healthy" population, and c) comparison with other MMSE versions.

RESULTS

The instrument fulfills criteria of "feasibility", "content", "procedural" and "construct validity". Test-retest reliability: weighted kappa = 0.637. MEC-30 (cut-off point 23/24), sensitivity = 89.8%, specificity = 75.1% (80.8% with the cut-off at 22/23), and ROC curve, AUC = 0.920. The coefficients of individual items were satisfactory and the specificity increases in MEC-35 (83.9%). Other MMSE Spanish versions have not improved these coefficients. "Population-based norms" confirm the hypothesized influence of age and education level. MEC-30 is the version with most comparable results with the MMSE in USA.

CONCLUSIONS

The validity of MEC is confirmed in the elderly population, with the same cut-off points recommended in the original standardization. MEC-30 is the best version for international comparisons.

Cross-cultural comparison of depressive symptoms in Europe does not support stereotypes of ageing

BACKGROUND

Stereotypes of older people suggest that they are depressed.

AIMS

To examine depression symptoms among people aged > or = 65 in the general population and to ask the following questions. Are there high proportions of depressive symptoms among otherwise well people? Do these levels reflect the prevalence of depression? Do key symptoms vary with age and do they confirm stereotypes?

METHOD

Nine centres contributed data from community-based random samples, using standardised methods (GMS-AGECAT package).

RESULTS

Proportions of depressive symptoms varied between centres. Some often associated with ageing were rare. Many were more common in women. Low-prevalence centres tended to have fewer symptoms among 'well' people, but there were inconsistencies. Low levels of symptoms among the well population of a centre did not necessarily predict lower levels in the depressed.

CONCLUSIONS

Variations in the prevalence of depressive symptoms occurred between centres, not always related to levels of illness. There was no consistent relationship between proportions of symptoms in well persons and cases for all centres. Few symptoms were present in > 60% of the older population--stereotypes of old age were not upheld.

Development of the EURO-D scale--a European, Union initiative to compare symptoms of depression in 14 European centres

BACKGROUND

In an 11-country European collaboration, 14 population-based surveys included 21,724 subjects aged > or = 65 years. Most participating centres used the Geriatric Mental State (GMS), but other measures were also used.

AIMS

To derive from these instruments a common depression symptoms scale, the EURO-D, to allow comparison of risk factor profiles between centres.

METHOD

Common items were identified from the instruments. Algorithms for fitting items to GMS were derived by observation of item correspondence or expert opinion. The resulting 12-item scale was checked for internal consistency, criterion validity and uniformity of factor-analytic profile.

RESULTS

The EURO-D is internally consistent, capturing the essence of its parent instrument. A two-factor solution seemed appropriate: depression, tearfulness and wishing to die loaded on the first factor (affective suffering), and loss of interest, poor concentration and lack of enjoyment on the second (motivation).

CONCLUSIONS

The EURO-D scale should permit valid comparison of risk-factor associations between centres, even if between-centre variation remains difficult to attribute.

Depression in Europe. Geographical distribution among older people

BACKGROUND

This is the first report of results from the EURODEP Programme.

AIMS

To assess the prevalence of depression judged suitable for intervention in randomised samples of those aged > or = 65 in nine European centres.

METHOD

The GMS-AGECAT package.

RESULTS

Differences in prevalence are apparent, 8.8% (Iceland) to 236% (Munich). When sub-cases and cases are added together, five high- and four low-scoring centres emerge. Women predominated over men. Proportions of sub-cases to cases revealed striking differences but did not explain prevalence. There was no constant association between prevalence and age. A meta-analysis (n = 13,808) gave an overall prevalence of 12.3%, 14.1% for women and 8.6% for men.

CONCLUSIONS

Considerable variation occurs in the levels of depression across Europe, the cause for which is not immediately obvious. Case and sub-case levels taken together show greater variability, suggesting that it is not a matter of case/sub-case selection criteria, which were standardised by computer. Substantial levels of depression are shown but 62-82% of persons had no depressive level. Opportunities for treatment exist.