Health status risk factors and quality of life in 75-84-year-old individuals assessed for dementia using the short 10/66 dementia diagnostic schedule.

BACKGROUND: Trinidad is an island that not only has a population at high vascular risk but also one that is in epidemiological transition with high dementia prevalence. The aim of the study was to investigate modifiable risk factors associated with dementia in middle-old (75-84 years) individuals. METHODS: As part of a large national community survey of dementia prevalence in Trinidad, 811 people aged 75-84 years were evaluated for dementia using the 10/66 short algorithm. Demographic data collected included information on age, gender, ethnicity, religion, education, occupation, living accommodation, smoking, alcohol consumption, self-reported medical conditions, impairments and ability to do instrumental activities of daily living (IADL). Data were analysed using multivariable logistic regression models. RESULTS: Of the 811 participants, nearly 55% were female. The mean age was 78.8 (SD = 2.8) years and dementia was present in 198 (24.4%). Having less than ten years of education, being an agricultural worker, skilled labourer or housewife and having more than four co-morbidities were significantly associated with dementia. The odds ratio for dementia for those having self-reported stroke was 4.93 (95% CI [2.64-9.23]) and for diabetes was 1.76 (95% CI [1.17-2.65]) adjusting for age, age2, gender, ethnicity, religion, education and occupation. Impairment in eyesight, hearing, climbing stairs, and walking were also more common in the group with dementia. Ability to perform IADLs was linked with dementia. Individuals with dementia were more likely to be unable to perform any of the eight IADLs. Those who did not exercise at all (OR 6.95, 95% CI [2.02-23.90]) and those who did low exercise (OR 1.83, 95% CI [1.07-3.13]) compared to those who did moderate to high exercise were also more likely to have dementia. CONCLUSION: In the middle-old population in Trinidad having diabetes and stroke, low IADL score, and no exercise were more common in people with dementia.

Comparisons between different elements of reported burden and common mental disorder in caregivers of ethnically diverse people with dementia in Trinidad.

OBJECTIVE: Culture plays a significant role in determining family responsibilities and possibly influences the caregiver burden associated with providing care for a relative with dementia. This study was carried out to determine the elements of caregiver burden in Trinidadians regarding which interventions will provide the most benefit. METHODS: Seventy-five caregivers of patients diagnosed with dementia participated in this investigation. Demographic data were recorded for each caregiver and patient. Caregiver burden was assessed using the Zarit Burden Interview (ZBI), and the General Health Questionnaire (GHQ) was used as a measure of psychiatric morbidity. Statistical analyses were performed using Stata and SPSS software. Associations between individual ZBI items and GHQ-28 scores in caregivers were analyzed in logistic regression models; the above-median GHQ-28 scores were used a binary dependent variable, and individual ZBI item scores were entered as 5-point ordinal independent variables. RESULTS: The caregiver sample was composed of 61 females and 14 males. Caregiver burden was significantly associated with the participant being male; there was heterogeneity by ethnic group, and a higher burden on female caregivers was detected at borderline levels of significance. Upon examining the associations between different ZBI items and the above-median GHQ-28 scores in caregivers, the strongest associations were found with domains reflecting the caregiver's health having suffered, the caregiver not having sufficient time for him/herself, the caregiver's social life suffering, and the caregiver admitting to feeling stressed due to caregiving and meeting other responsibilities. CONCLUSIONS: In this sample, with a majority of female caregivers, the factors of the person with dementia being male and belonging to a minority ethnic group were associated with a greater degree of caregiver burden. The information obtained through the association of individual ZBI items and above-median GHQ-28 scores is a helpful guide for profiling Trinidadian caregiver burden.

Dementia prevalence in a population at high vascular risk: the Trinidad national survey of ageing and cognition.

OBJECTIVE: To investigate the dementia prevalence in a country with high levels of cardiovascular risk factors DESIGN AND METHODS: Older people in Trinidad are recognised to have particularly high levels of cardiovascular risk factors. We carried out a survey in a nationally representative sample of people aged ≥70 years using household enumeration. Dementia status was ascertained using standardised interviews and algorithms from the 10/66 schedule and age-specific prevalence were compared with identically defined output from the 10/66 surveys of 16 536 residents in eight other low-income and middle-income countries. RESULTS: Of 1832 participants (77.0% response rate), dementia was present in 442 (23.4%). Prevalences were 12.0% in persons aged 70-74 years, 23.5% at 75-79, 25.8% at 80-84, 41.3% at 85-89 and 54.0% in those aged ≥90 years. Prevalence ratios compared with averages from 10/66 surveys in these age groups were 2.2, 2.6, 1.6, 1.7 and 1.6, respectively, and were 2.7, 2.8, 1.7, 1.4 and 0.8, respectively, compared with previously published consensus estimates for the Latin American region. Dementia was significantly associated with reported stroke and diabetes in logistic regression models adjusted for sociodemographic status and other vascular risk factors (OR (95% CI) 4.40 (2.70 to 7.19) and 1.56 (1.20 to 2.03), respectively). Projected national numbers of people with dementia (18 206) were 70%-100% higher than those estimated using most recent regional consensus prevalences. CONCLUSION: In a nation with high levels of vascular risk, dementia prevalence is higher than expected, particularly at the lower end of the 70+ age range. International prevalence projections may need to take into account risk status as well as age structures.

Microstructural characteristics and gastro-small intestinal digestion in vitro of potato starch: Effects of refrigerated storage and reheating in microwave.

The objective of our study was to evaluate paste clarity, retrogradation (syneresis %), thermal characteristics and kinetics of glucose release during in vitro gastro-small intestinal digestion of freshly cooked and refrigerated potato starch. Freshly cooked starch pastes had a paste clarity of 71%, which decreased to 35.4% whereas syneresis (%) increased after 7days of refrigerated storage. The X-ray and thermal characteristics of native, retrograded and microwave reheated starch samples differed significantly from each other. For the freshly cooked starch pastes, ∼88% starch hydrolysis was observed at the end (150min) of digestion under simulated gastro-small intestinal conditions that decreased to ∼70% for the 7day stored pastes. The hydrolysis (%) of refrigerated pastes increased to 86% and 92% after one and two cycles of microwave reheating, respectively. These results contribute to the understanding of starch retrogradation in relation to starch digestion.

Development of a brief assessment and algorithm for ascertaining dementia in low-income and middle-income countries: the 10/66 short dementia diagnostic schedule.

OBJECTIVES: To develop and evaluate a short version of the 10/66 dementia diagnostic schedule for use in low-income and middle-income countries. DESIGN: Split-half analysis for algorithm development and testing; cross-evaluation of short-schedule and standard-schedule algorithms in 12 community surveys. SETTINGS: (1) The 10/66 pilot sample data set of people aged 60 years and over in 25 international centres each recruiting the following samples: (a) dementia; (b) depression, no dementia; (c) no dementia, high education and (d) no dementia, low education. (2) Cross-sectional surveys of people aged 65 years or more from 12 urban and rural sites in 8 countries (Cuba, Dominican Republic, Peru, Mexico, Venezuela, India, China and Puerto Rico). PARTICIPANTS: In the 10/66 pilot samples, the algorithm for the short schedule was developed in 1218 participants and tested in 1211 randomly selected participants; it was evaluated against the algorithm for the standard 10/66 schedule in 16 536 survey participants. OUTCOME MEASURES: The short diagnostic schedule was derived from the Community Screening Instrument for Dementia, the CERAD 10-word list recall task and the Euro-D depression screen; it was evaluated against clinically assigned groups in the pilot data and against the standard schedule (using the Geriatric Mental State (GMS) rather than Euro-D) in the surveys. RESULTS: In the pilot test sample, the short-schedule algorithm ascertained dementia with 94.2% sensitivity. Specificities were 80.2% in depression, 96.6% in the high-education group and 92.7% in the low-education group. In survey samples, it coincided with standard algorithm dementia classifications with over 95% accuracy in most sites. Estimated dementia prevalences in the survey samples were not consistently higher or lower using the short compared to standard schedule. CONCLUSIONS: For epidemiological studies of dementia in low-income and middle-income settings where the GMS interview (and/or interviewer training required) is not feasible, the short 10/66 schedule and algorithm provide an alternative with acceptable levels of performance.

Change in Angular Alignment Is Associated With Early Dysphagia After Anterior Cervical Discectomy and Fusion.

STUDY DESIGN: Retrospective analysis of a prospective cohort. OBJECTIVE: Change in cervical angular alignment may be associated with dysphagia. SUMMARY OF BACKGROUND DATA: Bony deformities of the cervical spine may be associated with secondary contractures of soft tissues in the neck. Acute surgical deformity correction causes in changes in soft tissue tension in the anterior neck, resulting in dysphagia. METHODS: The study population included patients undergoing 1 and 2 level elective anterior cervical discectomy and fusion for cervical myelopathy or radiculopathy. Preoperative and postoperative radiographs at 2 weeks were measured by a blinded observer for C2-C7 endplate angle, C2-C7 posterior vertebral body length, and occipital condyle plumb line distance on upright lateral radiographs at 2, 6, and 12 weeks postoperatively. Patients were prospectively queried about dysphagia incidence and severity using a numeric rating scale. Multiple linear regression analysis was used to determine the effect of change in radiographic parameters controlling for demographic characteristics. RESULTS: The study population included 25 patients with complete radiographs. The mean change in C2-C7 angle was -0.6 degrees (SD 9), the mean change in C2-C7 length was 1.7 mm (SD 26), the mean change in occipital condyle plumb line distance was 2.3 mm (SD 20).Multiple linear regression analysis was performed including operative time, age, sex, number of levels, and change in radiographic parameters as independent variables and using dysphagia score as the dependent variable. The change in C2-C7 angle and operative time were the only statistically significant predictors of change in dysphagia at 2 and 6 weeks postoperatively. CONCLUSIONS: These results indicate that lordotic change in spinal alignment and longer operative times are associated with increased postoperative dysphagia. Surgeons should counsel patients in whom a large angular correction is expected about the possibility for postoperative dysphagia. Furthermore, future studies on dysphagia incidence should include radiographic alignment as an independent predictor of dysphagia.

Zinc and Vitamin Supplementation in an Under-5 Indigenous Population of Guatemala: Influence of Lay Health Promoters in Decreasing Incidence of Diarrhea.

BACKGROUND: Malnutrition is an urgent problem in the developing world, especially for children under 5 years of age. The article describes the utilization of a standard of practice designed to prevent illness in a malnourished, under-5 indigenous population and reinforced by weekly basic health messages taught by lay community health promoters. METHOD: The two villages were chosen for observation after administration of the standard of care among the Maya-Kíché, the most numerous Mayan group in Guatemala. The standard of practice, 20 mg of daily oral zinc, was administered for 10 days in the home and followed by daily vitamin supplementation that continued throughout the 3 months of the project. All patients received four monthly clinic visits, with one of the village groups receiving weekly health promoter visits. RESULTS: Data evaluated after the quality improvement project showed significant differences in adherence to the zinc regimen (χ(2) = 3.677, p ≤ .05) as well as lower rates of diarrheal illnesses (χ(2) = 5.850, p ≤ .05), with both of these improved in the health promoter group. DISCUSSION: This study suggests that the training and implementation of para-health professionals from the lay community in response to specific health care needs could be considered a best practice in developing countries. IMPLICATIONS: Public health professionals are key to health promoter training and direction, and their importance in the global setting cannot be understated.

Construct validity of the mini mental state examination across time in a sample with low-education levels: 10-year follow-up of the Bambuí Cohort Study of Ageing.

OBJECTIVE: The study aims to investigate whether longitudinal data on the structure of the mini mental state examination (MMSE) collected in an older Brazilian cohort support factorial invariance over time. DESIGN: Analysis of 10-year data from a community-based cohort study was performed. SETTING: The study took place in Bambuí, Brazil. PARTICIPANTS: The study sample comprised 1558 (89.4%) of all eligible 1742 elderly residents. MEASUREMENTS: A standard Brazilian version of the MMSE was used. RESULTS: A five-factor solution (developed on the baseline of the cohort) either with no constraints or with loadings constrained to equality across time provided a reasonable fit for the MMSE. A comparison between both models suggested that the model with no constraints was superior. However, the five absolute goodness-of-fit indices suggest that the fully constrained model was also adequate and did not differ substantively from the model without any restriction. CONCLUSION: The structure of the MMSE remained relatively unchanged across the 10 measurement times, thus providing evidence for the good construct validity of the scale across time.

The association of dementia with upper arm and waist circumference in seven low- and middle-income countries: the 10/66 cross-sectional surveys.

BACKGROUND: Weight loss in dementia contributes to morbidity and mortality but the distribution of anthropometric change and its consistency between populations are less clear. Our aim was to investigate and compare the associations of dementia with waist and upper arm circumference in elders from seven low- and middle-income nations. METHODS: Cross-sectional surveys were conducted of 15,022 residents aged 65 years and older in Cuba, Mexico, Venezuela, Peru, Dominican Republic, China, and India. Dementia was assessed using a cross-culturally validated algorithm, and anthropometric measurements were taken. Associations with dementia and dementia severity (clinical dementia rating scale) were investigated in linear regression models, with fixed-effects meta-analyses used to investigate between-country heterogeneity. RESULTS: Dementia and increased dementia severity were both associated with smaller arm and waist circumferences with little evidence of confounding by sociodemographic and health status. Associations between dementia/clinical dementia rating and arm circumference were homogeneous between countries (Higgins I(2) 0% and 7%, respectively), whereas those with waist circumference were more heterogeneous (Higgins I(2) 67% and 62%, respectively). CONCLUSIONS: Although cross-sectional, our findings are consistent with prospective observations of weight loss in dementia and suggest loss of both muscle and fat-the former being consistent across different settings and the latter being more context dependent.

Prevalence, distribution, and impact of mild cognitive impairment in Latin America, China, and India: a 10/66 population-based study.

BACKGROUND: Rapid demographic ageing is a growing public health issue in many low- and middle-income countries (LAMICs). Mild cognitive impairment (MCI) is a construct frequently used to define groups of people who may be at risk of developing dementia, crucial for targeting preventative interventions. However, little is known about the prevalence or impact of MCI in LAMIC settings. METHODS AND FINDINGS: Data were analysed from cross-sectional surveys established by the 10/66 Dementia Research Group and carried out in Cuba, Dominican Republic, Peru, Mexico, Venezuela, Puerto Rico, China, and India on 15,376 individuals aged 65+ without dementia. Standardised assessments of mental and physical health, and cognitive function were carried out including informant interviews. An algorithm was developed to define Mayo Clinic amnestic MCI (aMCI). Disability (12-item World Health Organization disability assessment schedule [WHODAS]) and informant-reported neuropsychiatric symptoms (neuropsychiatric inventory [NPI-Q]) were measured. After adjustment, aMCI was associated with disability, anxiety, apathy, and irritability (but not depression); between-country heterogeneity in these associations was only significant for disability. The crude prevalence of aMCI ranged from 0.8% in China to 4.3% in India. Country differences changed little (range 0.6%-4.6%) after standardization for age, gender, and education level. In pooled estimates, aMCI was modestly associated with male gender and fewer assets but was not associated with age or education. There was no significant between-country variation in these demographic associations. CONCLUSIONS: An algorithm-derived diagnosis of aMCI showed few sociodemographic associations but was consistently associated with higher disability and neuropsychiatric symptoms in addition to showing substantial variation in prevalence across LAMIC populations. Longitudinal data are needed to confirm findings-in particular, to investigate the predictive validity of aMCI in these settings and risk/protective factors for progression to dementia; however, the large number affected has important implications in these rapidly ageing settings.

Trajectories of cognitive decline over 10 years in a Brazilian elderly population: the Bambuí Cohort Study of Aging.

Few population-based studies have examined long term cognitive trajectory, and these studies were conducted in high income countries. We investigated the association of age, gender and education with 10-year cognitive trajectory in a well-defined population of elderly using data from the Bambuí Cohort Study of Aging, in Brazil. Cognition was measured using the Mini- Mental State Examination (MMSE). Cohort members underwent annual follow-ups. This analysis was based on 12,206 MMSE measurements from 1,461 (91%) baseline participants. We used mixed effects models to study MMSE as outcome. The key findings from this analysis are that women and people with a higher schooling level at baseline had high scores of MMSE, while older participants started off lower. Regarding cognitive decline, women, older people and those with a higher schooling level declined faster.

Insomnia subtypes and their relationship to excessive daytime sleepiness in Brazilian community-dwelling older adults.

STUDY OBJECTIVES: To investigate the association between different types of insomnia as exposures and excessive daytime sleepiness (EDS) as a binary outcome in older Brazilian residents. DESIGN: The baseline examination of the Bambuí Health and Ageing Study (BHAS), which is an ongoing population-based prospective cohort study of older adults. SETTING: Bambuí (15,000 inhabitants), a city in the State of Minas Gerais, Southeast Brazil PARTICIPANTS: All residents aged ≥ 60 years were eligible to take part in the BHAS baseline. Of 1742 residents identified who were ≥ 60 years, 1606 (92.2%) were interviewed and received comprehensive examinations of health status. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: EDS was defined as the presence of sleepiness ≥ 3 times per week in the last month, causing any interference in usual activities. All insomnia subtypes were significantly associated with EDS in unadjusted analyses, and these associations were only modestly altered after adjusting incrementally for the other covariates. In a final model, the 3 insomnia subtypes were entered into a fully adjusted model simultaneously to investigate mutual independence, giving prevalence ratios of 1.63 (95% CI 1.14-2.31) for initial insomnia, 2.13 (95% CI 1.48-3.07) for middle insomnia, and 1.36 (95% CI 0.94-1.96) for terminal insomnia. The population attributable fractions for initial, middle, and terminal insomnia on prevalence of EDS were 17.6%, 32.9%, and 9.7%, respectively. CONCLUSIONS: Middle insomnia emerged as the insomnia subtype most strongly associated with EDS. Further research is required to clarify causal pathways underlying this cross-sectional association.

Association between sleep duration and all-cause mortality in old age: 9-year follow-up of the Bambuí Cohort Study, Brazil.

This study investigates the association of sleep duration with risk of all-cause mortality among elderly Brazilians using data from a 9-year population-based cohort study and applying a multivariable longitudinal categorical and continuous analysis using Cox's proportional hazards models. This analysis used data from the Bambui Health and Ageing Study (BHAS), conducted in Bambuí city (approximately 15000 inhabitants) in southeastern Brazil. The study population comprised 1512 (86.8%) of all eligible 1742 elderly residents. In multivariable analysis, using sleep duration as categorical variable and controlling for multiple measures of sociodemographic and health status, those who slept 9h or more per night were found to be at higher risk of mortality than those who slept 7h [hazard ratio (HR): 1.53; 95% confidence interval (CI): 1.12-2.09]. Excluding those whose deaths occurred within 2years after entry, this association remained significant (HR: 1.56; 95% CI: 1.12-2.18). In analyses using sleep duration as a continuous variable, a linear correlation was found between sleep duration and mortality in all adjusted models in the whole sample (HR: 1.08; 95% CI: 1.02-1.15) and following exclusion of those whose deaths occurred within 2years after entry (HR: 1.13; 95% CI: 1.06-1.21). Both linear and quadratic terms were significant, reflecting a predicted relationship, with mortality predominantly increasing in association with long sleep duration but with the addition of a slight decrease in association with shorter sleep duration. In conclusion, long rather than short sleep duration was associated principally with all-cause mortality in this sample. It is therefore reasonable to suggest that clinicians should be aware of the potential adverse prognosis associated with prolonged sleep.

Leg length, skull circumference, and the prevalence of dementia in low and middle income countries: a 10/66 population-based cross sectional survey.

BACKGROUND: Adult leg length is influenced by nutrition in the first few years of life. Adult head circumference is an indicator of brain growth. There is a limited literature linking short legs and small skulls to an increased risk for cognitive impairment and dementia in late life. METHODS: One phase cross-sectional surveys were carried out of all residents aged over 65 years in 11 catchment areas in China, India, Cuba, Dominican Republic, Venezuela, Mexico and Peru (n = 14,960). The cross-culturally validated 10/66 dementia diagnosis, and a sociodemographic and risk factor questionnaire were administered to all participants, and anthropometric measures taken. Poisson regression was used to calculate prevalence ratios for the effect of leg length and skull circumference upon 10/66 dementia, controlling for age, gender, education and family history of dementia. RESULTS: The pooled meta-analyzed fixed effect for leg length (highest vs. lowest quarter) was 0.82 (95% CI, 0.68-0.98) and for skull circumference 0.75 (95% CI, 0.63-0.89). While point estimates varied between sites, the proportion of the variability attributable to heterogeneity between studies as opposed to sampling error (I2) was 0% for leg length and 22% for skull circumference. The effects were independent and not mediated by family history of dementia. The effect of skull circumference was not modified by educational level or gender, and the effect of leg length was not modified by gender. CONCLUSIONS: Since leg length and skull circumference are said to remain stable throughout adulthood into old age, reverse causality is an unlikely explanation for the findings. Early life nutritional programming, as well as neurodevelopment may protect against neurodegeneration.

Trajectories of cognitive decline over 10 years in a Brazilian elderly population: the Bambuí cohort study of aging / Trajetória no longo prazo do declínio cognitivo entre idosos Brasileiros: estudo de coorte de idosos de Bambuí

Few population-based studies have examined long term cognitive trajectory, and these studies were conducted in high income countries. We investigated the association of age, gender and education with 10-year cognitive trajectory in a well-defined population of elderly using data from the Bambuí Cohort Study of Aging, in Brazil. Cognition was measured using the Mini- Mental State Examination (MMSE). Cohort members underwent annual follow-ups. This analysis was based on 12,206 MMSE measurements from 1,461 (91 percent) baseline participants. We used mixed effects models to study MMSE as outcome. The key findings from this analysis are that women and people with a higher schooling level at baseline had high scores of MMSE, while older participants started off lower. Regarding cognitive decline, women, older people and those with a higher schooling level declined faster.

Poucos estudos de base populacional examinaram a trajetória no longo prazo do declínio cognitivo. Os estudos existentes foram conduzidos em países de alta renda. Nós investigamos as associações entre idade, sexo e escolaridade e o declínio cognitivo em uma população idosa bem definida, utilizando dados de 10 anos de seguimento da coorte de Bambuí, Minas Gerais, Brasil. A cognição foi aferida anualmente por meio do Mini-Exame do Estado Mental (MEEM). Essa análise foi baseada em 12.206 medidas do MEEM de 1.461 (90 por cento) participantes da linha de base. Foram utilizados modelos de efeitos mistos, considerando-se o escore do MEEM como variável de desfecho. As mulheres e os indivíduos com maior escolaridade apresentaram resultados mais altos no MEEM na linha de base, enquanto que os idosos mais velhos apresentaram pontuações mais baixas. Com relação ao declínio cognitivo, participantes do sexo feminino, com maior escolaridade e mais velhos, apresentam reduções mais rápidas dos escores do MEEM.

Dimensions underlying the mini-mental state examination in a sample with low-education levels: the Bambuí health and aging study.

OBJECTIVES: To investigate the validity of previously suggested dimensions underlying the Mini-Mental State Examination (MMSE) and differences in associations of these dimensions with sociodemographic and health characteristics in an older Latin-American community sample with low levels of education. DESIGN: Secondary analysis of baseline data from a population-based cohort study. SETTING: Bambuí, Brazil. PARTICIPANTS: Of 1,742 total residents aged 60 years or older, 1,558 (89.4%) participated at this study. MEASUREMENTS: A standard Brazilian version of the MMSE. RESULTS: A five-factor solution (Concentration, Language/Praxis, Orientation, Attention, and Memory) for the MMSE was generated from Principal Components Analysis, and the five-factor solutions proposed in previous studies of developed nation samples were tested in this sample by Confirmatory Factor Analysis. In the adjusted linear regression models, MMSE factors varied in their correlates: for example, female gender was associated with higher concentration, orientation, and attention but lower Language/Praxis; increased age was inversely associated only with language and attention; and activity of daily living impairment was principally associated with lower Language/Praxis. CONCLUSION: This study provides support for the cross-sectional equivalence of the MMSE, suggesting that most of the items and underlying constructs remain meaningful after alteration and translation in a low-education sample with lower overall distribution of scores.

Population normative data for the 10/66 Dementia Research Group cognitive test battery from Latin America, India and China: a cross-sectional survey.

BACKGROUND: 1) To report site-specific normative values by age, sex and educational level for four components of the 10/66 Dementia Research Group cognitive test battery; 2) to estimate the main and interactive effects of age, sex, and educational level by site; and 3) to investigate the effect of site by region and by rural or urban location. METHODS: Population-based cross-sectional one phase catchment area surveys were conducted in Cuba, Dominican Republic, Venezuela, Peru, Mexico, China and India. The protocol included the administration of the Community Screening Instrument for Dementia (CSI 'D', generating the COGSCORE measure of global function), and the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) verbal fluency (VF), word list memory (WLM, immediate recall) and recall (WLR, delayed recall) tests. Only those free of dementia were included in the analysis. RESULTS: Older people, and those with less education performed worse on all four tests. The effect of sex was much smaller and less consistent. There was a considerable effect of site after accounting for compositional differences in age, education and sex. Much of this was accounted for by the effect of region with Chinese participants performing better, and Indian participants worse, than those from Latin America. The effect of region was more prominent for VF and WLM than for COGSCORE and WLR. CONCLUSION: Cognitive assessment is a basic element for dementia diagnosis. Age- and education-specific norms are required for this purpose, while the effect of gender can probably be ignored. The basis of cultural effects is poorly understood, but our findings serve to emphasise that normative data may not be safely generalised from one population to another with quite different characteristics. The minimal effects of region on COGSCORE and WLR are reassuring with respect to the cross-cultural validity of the 10/66 dementia diagnosis, which uses only these elements of the 10/66 battery.

Analysis of Mercury-Rich plants and mine tailings using the Hydride-Generation AAS method

A hydride-generation atomic absorption spectroscopy (AAS) method was developed for the analysis of total Hg in liquid matrices of mercury-rich plants and mine tailings samples. The detection limit for this method was as low as 11.4 ng/mL. The reproducibility of the mercury signals (in terms of relative standard deviation) was 4.6 percent. Accuracy of the method was verified by analyses of deionised water samples spiked with HgCl2 and HgNO3. Recovery values for total mercury ranged from 88.5 to 94.3 percent for both mercury species added. An external certified laboratory validated the analytical method with a maximum discrepancy of 15 percent. Optimal analytical response of the equipment for Hg analysis of plant samples was achieved when the sample volume added to the reaction vessel was 0.25 mL.

Um protocolo para análise do mercúrio (Hg) em amostras líquidas de solo e tecidos vegetais enriquecidos com Hg foi desenvolvido com base na técnica de geração de hidretos. O limite de detecção para este método foi de 11.4 ng/mL. A reproducibilidade do método (calculado com base no desvio padrão relativo) foi de 4.6 por cento. A precisão do método foi verificada pela análise de amostras de água deionizada contendo HgCl2 and HgNO3. Os valores de mercúrio total recuperados variaram de 88.5 a 94.3 por cento para ambas as espécies testadas. O método analítico foi validado por um laboratório externo certificado com discrepância máxima de 15 por cento. O desempenho analítico do equipamento para análise do mercúrio em tecidos vegetais foi considerado ótimo para volumes de amostra de até 0.25 mL.

The 10/66 Dementia Research Group's fully operationalised DSM-IV dementia computerized diagnostic algorithm, compared with the 10/66 dementia algorithm and a clinician diagnosis: a population validation study.

BACKGROUND: The criterion for dementia implicit in DSM-IV is widely used in research but not fully operationalised. The 10/66 Dementia Research Group sought to do this using assessments from their one phase dementia diagnostic research interview, and to validate the resulting algorithm in a population-based study in Cuba. METHODS: The criterion was operationalised as a computerised algorithm, applying clinical principles, based upon the 10/66 cognitive tests, clinical interview and informant reports; the Community Screening Instrument for Dementia, the CERAD 10 word list learning and animal naming tests, the Geriatric Mental State, and the History and Aetiology Schedule - Dementia Diagnosis and Subtype. This was validated in Cuba against a local clinician DSM-IV diagnosis and the 10/66 dementia diagnosis (originally calibrated probabilistically against clinician DSM-IV diagnoses in the 10/66 pilot study). RESULTS: The DSM-IV sub-criteria were plausibly distributed among clinically diagnosed dementia cases and controls. The clinician diagnoses agreed better with 10/66 dementia diagnosis than with the more conservative computerized DSM-IV algorithm. The DSM-IV algorithm was particularly likely to miss less severe dementia cases. Those with a 10/66 dementia diagnosis who did not meet the DSM-IV criterion were less cognitively and functionally impaired compared with the DSMIV confirmed cases, but still grossly impaired compared with those free of dementia. CONCLUSION: The DSM-IV criterion, strictly applied, defines a narrow category of unambiguous dementia characterized by marked impairment. It may be specific but incompletely sensitive to clinically relevant cases. The 10/66 dementia diagnosis defines a broader category that may be more sensitive, identifying genuine cases beyond those defined by our DSM-IV algorithm, with relevance to the estimation of the population burden of this disorder.

Leg length, cognitive impairment and cognitive decline in an African-Caribbean population.

BACKGROUND: Shorter leg length is associated with an adverse environment in early childhood and has been found to be associated with a variety of disorders occurring in mid- to late-life, including dementia in a Korean population. In a community population of African-Caribbean elders, in whom leg length had been measured, we sought to compare associations with cognitive impairment at baseline and cognitive decline over a three-year follow-up period. METHODS: Of 290 African-Caribbean residents in south London recruited at baseline, 216 (74%) were re-interviewed after a three-year period and 203 had sufficient data for this analysis. Cognitive impairment was derived as a binary category from a battery of cognitive tests administered at baseline and cognitive decline was derived from change in performance on a subset of these tests. Leg length (iliac crest to lateral malleolus) was also measured. RESULTS: Shorter leg length was associated with female sex, lower occupational social class and reported hypertension and diabetes. Shorter leg length (lowest quartile) was significantly associated with cognitive impairment but there were no apparent associations with cognitive decline. The association with cognitive impairment was independent of age, sex and education. Social class appeared to be an important mediating factor. CONCLUSIONS: Shorter leg length may be a marker of early life stressors which result in reduced cognitive reserve. Interestingly this association was mediated more strongly by social class (previous occupational status) than by education in this population.