Loneliness Among Older Adults in Latin America, China, and India: Prevalence, Correlates and Association With Mortality.

Objectives: This study was designed to explore prevalence and correlates of self-reported loneliness and to investigate whether loneliness predicts mortality among older adults (aged 65 or above) in Latin America, China and India. Methods: The study investigated population-based cross-sectional (2003-2007) and longitudinal surveys (follow-up 2007-2010) from the 10/66 Dementia Research Group project. Poisson regression and Cox regression analyses were conducted to analyse correlates of loneliness and its association with mortality. Results: The standardised prevalence of loneliness varied between 25.3 and 32.4% in Latin America and was 18.3% in India. China showed a low prevalence of loneliness (3.8%). In pooled meta-analyses, there was robust evidence to support an association between loneliness and mortality across Latin American countries (HR = 1.13, 95% CI 1.01-1.26, I2 = 10.1%) and China (HR = 1.58, 95% CI 1.03-2.41), but there were no associations in India. Conclusion: Our findings suggest potential cultural variances may exist in the concept of loneliness in older age. The effect of loneliness upon mortality is consistent across different cultural settings excluding India. Loneliness should therefore be considered as a potential dimension of public health among older populations.

A Review of Thermal Property Enhancements of Low-Temperature Nano-Enhanced Phase Change Materials.

Phase change materials (PCMs) are of increasing interest due to their ability to absorb and store large amounts of thermal energy, with minimal temperature variations. In the phase-change process, these large amounts of thermal energy can be stored with a minimal change in temperature during both the solid/liquid and liquid/vapor phase transitions. As a result, these PCMs are experiencing increased use in applications such as solar energy heating or storage, building insulation, electronic cooling, food storage, and waste heat recovery. Low temperature, nano-enhanced phase change materials (NEPCM) are of particular interest, due to the recent increase in applications related to the shipment of cellular based materials and vaccines, both of which require precise temperature control for sustained periods of time. Information such as PCM and nanoparticle type, the effective goals, and manipulation of PCM thermal properties are assembled from the literature, evaluated, and discussed in detail, to provide an overview of NEPCMs and provide guidance for additional study. Current studies of NEPCMs are limited in scope, with the primary focus of a majority of recent investigations directed at increasing the thermal conductivity and reducing the charging and discharging times. Only a limited number of investigations have examined the issues related to increasing the latent heat to improve the thermal capacity or enhancing the stability to prevent sedimentation of the nanoparticles. In addition, this review examines several other important thermophysical parameters, including the thermal conductivity, phase transition temperature, rheological affects, and the chemical stability of NEPCMs. This is accomplished largely through comparing of the thermophysical properties of the base PCMs and their nano-enhanced counter parts and then evaluating the relative effectiveness of the various types of NEPCMs. Although there are exceptions, for a majority of conventional heat transfer fluids the thermal conductivity of the base PCM generally increases, and the latent heat decreases as the mass fraction of the nanoparticles increases, whereas trends in phase change temperature are often dependent upon the properties of the individual components. A number of recommendations for further study are made, including a better understanding of the stability of NEPCMs such that sedimentation is limited and thus capable of withstanding long-term thermal cycles without significant degradation of thermal properties, along with the identification of those factors that have the greatest overall impact and which PCM combinations might result in the most significant increases in latent heat.

The Prevalence and Correlates of Frailty in Urban and Rural Populations in Latin America, China, and India: A 10/66 Population-Based Survey.

BACKGROUND: There have been few cross-national studies of the prevalence of the frailty phenotype conducted among low or middle income countries. We aimed to study the variation in prevalence and correlates of frailty in rural and urban sites in Latin America, India, and China. METHODS: Cross-sectional population-based catchment area surveys conducted in 8 urban and 4 rural catchment areas in 8 countries; Cuba, Dominican Republic, Puerto Rico, Venezuela, Peru, Mexico, China, and India. We assessed weight loss, exhaustion, slow walking speed, and low energy consumption, but not hand grip strength. Therefore, frailty phenotype was defined on 2 or more of 4 of the usual 5 criteria. RESULTS: We surveyed 17,031 adults aged 65 years and over. Overall frailty prevalence was 15.2% (95% confidence inteval 14.6%-15.7%). Prevalence was low in rural (5.4%) and urban China (9.1%) and varied between 12.6% and 21.5% in other sites. A similar pattern of variation was apparent after direct standardization for age and sex. Cross-site variation in prevalence of frailty indicators varied across the 4 indicators. Controlling for age, sex, and education, frailty was positively associated with older age, female sex, lower socioeconomic status, physical impairments, stroke, depression, dementia, disability and dependence, and high healthcare costs. DISCUSSION: There was substantial variation in the prevalence of frailty and its indicators across sites in Latin America, India, and China. Culture and other contextual factors may impact significantly on the assessment of frailty using questionnaire and physical performance-based measures, and achieving cross-cultural measurement invariance remains a challenge. CONCLUSIONS: A consistent pattern of correlates was identified, suggesting that in all sites, the frailty screen could identify older adults with multiple physical, mental, and cognitive morbidities, disability and needs for care, compounded by socioeconomic disadvantage and catastrophic healthcare spending.

Impact of an HIV Prevention Intervention on HIV Risk Behavior and Sexually Transmitted Infection among Female Sex Workers in Tamil Nadu, India.

BACKGROUND: In 2003 a large-scale HIV prevention program was launched for key populations in six high HIV prevalence states of India. This paper assesses the effect of exposure to the intervention on condom use with commercial clients and experiences of sexually transmitted infection (STI) among female sex workers (FSWs) in Tamilnadu, a southern Indian state, between 2006 and 2009. METHODS: Data were drawn from two rounds of cross-sectional surveys conducted in 2006 (N = 2010) and 2009 (N = 2500) among FSWs in Tamilnadu, recruited through probability-based sampling. A series of multivariate logistic regression models were constructed to examine the association between exposure to the intervention and change over time with condom use and self-reported STI. All the analyses were performed using STATA 11.1. RESULTS: Overall, 48% of FSWs in 2006 and 90% in 2009 reported exposure to the intervention. Compared to 2006, there was a considerable increase in the proportion of FSWs reporting consistent condom use with regular and occasional clients at follow-up (2009). Further, the increase in consistent condom use over time with occasional (adjusted OR = 3.53, 95% CI: 2.47 - 5.05) and regular clients (adjusted OR = 4.97, 95% CI: 3.43 - 7.16) was significantly higher among FSWs exposed to the intervention than those not exposed. Additionally, a significant decline was observed in self-reported STI overtime among FSWs exposed to the intervention compared to their counterparts (adjusted OR = 0.39, 95% CI: 0.26 - 0.59). CONCLUSION: The HIV prevention program in Tamilnadu resulted in increased consistent condom use and a decrease in self-reported STI among FSWs exposed to intervention. These findings suggest that HIV prevention programs should aim to saturate coverage among key populations to sustain the gains achieved.

The Prevalence, Correlates, Detection and Control of Diabetes among Older People in Low and Middle Income Countries. A 10/66 Dementia Research Group Population-Based Survey.

BACKGROUND: Little is known of the epidemiology of diabetes among older people in low and middle income countries. We aimed to study and compare prevalence, social patterning, correlates, detection, treatment and control of diabetes among older people in Latin America, India, China and Nigeria. METHODS: Cross-sectional surveys in 13 catchment area sites in nine countries. Diagnosed diabetes was assessed in all sites through self-reported diagnosis. Undiagnosed diabetes was assessed in seven Latin American sites through fasting blood samples (glucose > = 7 mmol/L). RESULTS: Total diabetes prevalence in catchment sites in Cuba (prevalence 24.2%, SMR 116), Puerto Rico (43.4%, 197), and urban (27.0%, 125), and rural Mexico (23.7%, 111) already exceeds that in the USA, while that in Venezuela (20.9%, 100) is similar. Diagnosed diabetes prevalence varied very widely, between low prevalences in sites in rural China (0.9%), rural India (6.6%) and Nigeria (6.0%). and 32.1% in Puerto Rico, explained mainly by access to health services. Treatment coverage varied substantially between sites. Diabetes control (40 to 61% of those diagnosed) was modest in the Latin American sites where this was studied. Diabetes was independently associated with less education, but more assets. Hypertension, central obesity and hypertriglyceridaemia, but not hypercholesterolaemia were consistently associated with total diabetes. CONCLUSIONS: Diabetes prevalence is already high in most sites. Identifying undiagnosed cases is essential to quantify population burden, particularly in least developed settings where diagnosis is uncommon. Metabolic risk factors and associated lifestyles may play an important part in aetiology, but this requires confirmation with longitudinal data. Given the high prevalence among older people, more population research is indicated to quantify the impact of diabetes, and to monitor the effect of prevention and health system strengthening on prevalence, treatment and control.

Frailty and the prediction of dependence and mortality in low- and middle-income countries: a 10/66 population-based cohort study.

BACKGROUND: In countries with high incomes, frailty indicators predict adverse outcomes in older people, despite a lack of consensus on definition or measurement. We tested the predictive validity of physical and multidimensional frailty phenotypes in settings in Latin America, India, and China. METHODS: Population-based cohort studies were conducted in catchment area sites in Cuba, Dominican Republic, Venezuela, Mexico, Peru, India, and China. Seven frailty indicators, namely gait speed, self-reported exhaustion, weight loss, low energy expenditure, undernutrition, cognitive, and sensory impairment were assessed to estimate frailty phenotypes. Mortality and onset of dependence were ascertained after a median of 3.9 years. RESULTS: Overall, 13,924 older people were assessed at baseline, with 47,438 person-years follow-up for mortality and 30,689 for dependence. Both frailty phenotypes predicted the onset of dependence and mortality, even adjusting for chronic diseases and disability, with little heterogeneity of effect among sites. However, population attributable fractions (PAF) summarising etiologic force were highest for the aggregate effect of the individual indicators, as opposed to either the number of indicators or the dichotomised frailty phenotypes. The aggregate of all seven indicators provided the best overall prediction (weighted mean PAF 41.8 % for dependence and 38.3 % for mortality). While weight loss, underactivity, slow walking speed, and cognitive impairment predicted both outcomes, whereas undernutrition predicted only mortality and sensory impairment only dependence. Exhaustion predicted neither outcome. CONCLUSIONS: Simply assessed frailty indicators identify older people at risk of dependence and mortality, beyond information provided by chronic disease diagnoses and disability. Frailty is likely to be multidimensional. A better understanding of the construct and pathways to adverse outcomes could inform multidimensional assessment and intervention to prevent or manage dependence in frail older people, with potential to add life to years, and years to life.

Sexual behavior among unmarried business process outsourcing employees in Chennai: gender differences and correlates associated with it.

BACKGROUND: Premarital sex is often associated with high risk sexual behavior such as early age of initiation, multiple partners and inconsistent condom use. Evidence shows that such sexual behavior pre-disposes to sexually transmitted diseases including HIV. OBJECTIVES: This paper tried to investigate the correlates of premarital sexual behavior among male and female business process outsourcing (BPO) employees to highlight the gender differences that exist in relation to it. MATERIALS AND METHODS: Data were collected from 526 unmarried BPO employees during behavioral surveillance survey in Chennai, in the year 2009. RESULTS: The results showed that about one-third of respondents (males - 39.6%, females - 26.1%) had experienced premarital sex. Men reported having had their first sexual intercourse at 12 years and women at 16 years of age. While the prevalence of premarital sex was found to be high, the percentage using a condom during last sex was also high, especially, among the female employees (82.4%). Logistic regression showed that monthly individual income, work in shifts, migration, peer influence and friends with previous sexual experience were significant predictors of premarital sex among the male BPO employees. Visit to night clubs was significantly associated with a higher prevalence of premarital sex among the female employees. CONCLUSIONS: The study concludes that there is a significant gender dimension in the premarital sexual behavior among the BPO employees and that even as the sexual behavior of the young people is transitioning; their ability to negotiate safe sex behavior is also increasing. It is recommended to enhance efforts to advocate safe sex behavior among young adults employed in the BPO industry.

Dementia incidence and mortality in middle-income countries, and associations with indicators of cognitive reserve: a 10/66 Dementia Research Group population-based cohort study.

BACKGROUND: Results of the few cohort studies from countries with low incomes or middle incomes suggest a lower incidence of dementia than in high-income countries. We assessed incidence of dementia according to criteria from the 10/66 Dementia Research Group and Diagnostic and Statistical Manual of Mental Disorders (DSM) IV, the effect of dementia at baseline on mortality, and the independent effects of age, sex, socioeconomic position, and indicators of cognitive reserve. METHODS: We did a population-based cohort study of all people aged 65 years and older living in urban sites in Cuba, the Dominican Republic, and Venezuela, and rural and urban sites in Peru, Mexico, and China, with ascertainment of incident 10/66 and DSM-IV dementia 3-5 years after cohort inception. We used questionnaires to obtain information about age in years, sex, educational level, literacy, occupational attainment, and number of household assets. We obtained information about mortality from all sites. For participants who had died, we interviewed a friend or relative to ascertain the likelihood that they had dementia before death. FINDINGS: 12,887 participants were interviewed at baseline. 11,718 were free of dementia, of whom 8137 (69%) were reinterviewed, contributing 34,718 person-years of follow-up. Incidence for 10/66 dementia varied between 18·2 and 30·4 per 1000 person-years, and were 1·4-2·7 times higher than were those for DSM-IV dementia (9·9-15·7 per 1000 person-years). Mortality hazards were 1·56-5·69 times higher in individuals with dementia at baseline than in those who were dementia-free. Informant reports suggested a high incidence of dementia before death; overall incidence might be 4-19% higher if these data were included. 10/66 dementia incidence was independently associated with increased age (HR 1·67; 95% CI 1·56-1·79), female sex (0·72; 0·61-0·84), and low education (0·89; 0·81-0·97), but not with occupational attainment (1·04; 0·95-1·13). INTERPRETATION: Our results provide supportive evidence for the cognitive reserve hypothesis, showing that in middle-income countries as in high-income countries, education, literacy, verbal fluency, and motor sequencing confer substantial protection against the onset of dementia. FUNDING: Wellcome Trust Health Consequences of Population Change Programme, WHO, US Alzheimer's Association, FONACIT/ CDCH/ UCV.

Socioeconomic factors and all cause and cause-specific mortality among older people in Latin America, India, and China: a population-based cohort study.

BACKGROUND: Even in low and middle income countries most deaths occur in older adults. In Europe, the effects of better education and home ownership upon mortality seem to persist into old age, but these effects may not generalise to LMICs. Reliable data on causes and determinants of mortality are lacking. METHODS AND FINDINGS: The vital status of 12,373 people aged 65 y and over was determined 3-5 y after baseline survey in sites in Latin America, India, and China. We report crude and standardised mortality rates, standardized mortality ratios comparing mortality experience with that in the United States, and estimated associations with socioeconomic factors using Cox's proportional hazards regression. Cause-specific mortality fractions were estimated using the InterVA algorithm. Crude mortality rates varied from 27.3 to 70.0 per 1,000 person-years, a 3-fold variation persisting after standardisation for demographic and economic factors. Compared with the US, mortality was much higher in urban India and rural China, much lower in Peru, Venezuela, and urban Mexico, and similar in other sites. Mortality rates were higher among men, and increased with age. Adjusting for these effects, it was found that education, occupational attainment, assets, and pension receipt were all inversely associated with mortality, and food insecurity positively associated. Mutually adjusted, only education remained protective (pooled hazard ratio 0.93, 95% CI 0.89-0.98). Most deaths occurred at home, but, except in India, most individuals received medical attention during their final illness. Chronic diseases were the main causes of death, together with tuberculosis and liver disease, with stroke the leading cause in nearly all sites. CONCLUSIONS: Education seems to have an important latent effect on mortality into late life. However, compositional differences in socioeconomic position do not explain differences in mortality between sites. Social protection for older people, and the effectiveness of health systems in preventing and treating chronic disease, may be as important as economic and human development.

Strain and its correlates among carers of people with dementia in low-income and middle-income countries. A 10/66 Dementia Research Group population-based survey.

OBJECTIVES: In a multi-site population-based study in several middle-income countries, we aimed to investigate relative contributions of care arrangements and characteristics of carers and care recipients to strain among carers of people with dementia. Based on previous research, hypotheses focused on carer sex, care inputs, behavioural and psychological symptoms (BPSD) and socioeconomic status, together with potential buffering effects of informal support and employing paid carers. METHODS: In population-based catchment area surveys in 11 sites in Latin America, India and China, we analysed data collected from people with dementia and care needs, and their carers. Carer strain was assessed with the Zarit Burden Interview. RESULTS: With 673 care recipient/carer dyads interviewed (99% of those eligible), mean Zarit Burden Interview scores ranged between 17.1 and 27.9 by site. Women carers reported more strain than men. The most substantial correlates of carer strain were primary stressors BPSD, dementia severity, needs for care and time spent caring. Socioeconomic status was not associated with carer strain. Those cutting back on work experienced higher strain. There was tentative evidence for a protective effect of having additional informal or paid support. CONCLUSIONS: Our findings underline the global impact of caring for a person with dementia and support the need for scaling up carer support, education and training. That giving up work to care was prevalent and associated with substantial increased strain emphasizes the economic impact of caring on the household. Carer benefits, disability benefits for people with dementia and respite care should all be considered.

Hypertension prevalence, awareness, treatment and control among older people in Latin America, India and China: a 10/66 cross-sectional population-based survey.

OBJECTIVES: To estimate the prevalence, social patterning, treatment and control of hypertension among older people in the 10/66 Dementia Research Group developing country sites. METHODS: Cross-sectional surveys of SBP, hypertension, and hypertension awareness, treatment and control among 17 014 people aged 65 years and over in eight urban and four rural sites in Latin America, India and China. RESULTS: Hypertension prevalence was higher in urban (range 52.6-79.8%) than rural sites (range 42.6-56.9%), and lower in men than women [pooled prevalence ratio 0.89, 95% confidence interval (CI) 0.85-0.93]. Educational attainment was positively associated with hypertension in rural and least-developed sites. Age-standardized morbidity ratios, compared to USA (100), were higher in urban sites in Cuba (105), Dominican Republic (109), and Venezuela (107), similar in Puerto Rico (105), urban Mexico (99) and urban India (101), and lower in urban (75) and rural (61) Peru, rural Mexico (81), urban (91) and rural (84) China and rural India (65). In most Latin American centres, and urban China just over one-third of those with hypertension were controlled (BP < 140/90). Control was poor in rural China (2%), urban India (12%) and rural India (9%). The proportion controlled, not compositional factors (age, sex, education and obesity), explained most of the between-site variation in SBP. CONCLUSION: Uncontrolled hypertension is common among older people in developing countries, and may rise further during the demographic and health transitions. It is a major determinant of population SBP level. Strengthening primary care to improve hypertension management is necessary for primary prevention.

Prevalence of stroke and related burden among older people living in Latin America, India and China

Objectives Despite the growing importance of stroke in developing countries, little is known of stroke burden in survivors. The authors investigated the prevalence of self-reported stroke, stroke-related disability, dependence and care-giver strain in Latin America (LA), China and India. Methods Cross-sectional surveys were conducted on individuals aged 65+ (n=15 022) living in specified catchment areas. Self-reported stroke diagnosis, disability, care needs and care giver burden were assessed using a standardised protocol. For those reporting stroke, the correlates of disability, dependence and care-giver burden were estimated at each site using Poisson or linear regression, and combined meta-analytically.Results The prevalence of self-reported stroke ranged between 6 percent and 9 percent across most LA sites and urban China, but was much lower in urban India (1,9 percent), and in rural sites in India (1,1 percent), China (1,6 percent) and Peru (2.7 percent). The proportion of stroke survivors needing care varied between 20 percent and 39 percent in LA sites but was higher in rural China (44 percent), urban China (54 percent) and rural India (73 percent). Comorbid dementia and depression were the main correlates of disability and dependence. Conclusion The prevalence of stroke in urban LA and Chinese sites is nearly as high as in industrialised countries. High levels of disability and dependence in the other mainly rural and less-developed sites suggest underascertainment of less severe cases as one likely explanation for the lower prevalence in those settings. As the health transition proceeds, a further increase in numbers of older stroke survivors is to be anticipated. In addition to prevention, stroke rehabilitation and long-term care needs should be addressed(AU)

Equity in the delivery of community healthcare to older people: findings from 10/66 Dementia Research Group cross-sectional surveys in Latin America, China, India and Nigeria.

BACKGROUND: To describe patterns of recent health service utilisation, and consequent out-of-pocket expenses among older people in countries with low and middle incomes, and to assess the equity with which services are accessed and delivered. METHODS: 17,944 people aged 65 years and over were assessed in one-phase population-based cross-sectional surveys in geographically-defined catchment areas in nine countries - urban and rural sites in China, India, Mexico and Peru, urban sites in Cuba, Dominican Republic, Puerto Rico and Venezuela, and a rural site in Nigeria. The main outcome was use of community health care services in the past 3 months. Independent associations were estimated with indicators of need (dementia, depression, physical impairments), predisposing factors (age, sex, and education), and enabling factors (household assets, pension receipt and health insurance) using Poisson regression to generate prevalence ratios and fixed effects meta-analysis to combine them. RESULTS: The proportion using healthcare services varied from 6% to 82% among sites. Number of physical impairments (pooled prevalence ratio 1.37, 95% CI 1.26-1.49) and ICD-10 depressive episode (pooled PR 1.21, 95% CI 1.07-1.38) were associated with service use, but dementia was inversely associated (pooled PR 0.93, 95% CI 0.90-0.97). Other correlates were female sex, higher education, more household assets, receiving a pension, and health insurance. Standardisation for age, sex, physical impairments, depression and dementia did not explain variation in service use. There was a strong borderline significant ecological correlation between the proportion of consultations requiring out-of-pocket costs and the prevalence of health service use (r = -0.50, p = 0.09). CONCLUSIONS: While there was little evidence of ageism, inequity was apparent in the independent enabling effects of education and health insurance cover, the latter particularly in sites where out-of-pocket expenses were common, and private health insurance an important component of healthcare financing. Variation in service use among sites was most plausibly accounted for by stark differences in the extent of out-of-pocket expenses, and the ability of older people and their families to afford them. Health systems that finance medical services through out-of-pocket payments risk excluding the poorest older people, those without a secure regular income, and the uninsured.

Prevalence of stroke and related burden among older people living in Latin America, India and China.

OBJECTIVES: Despite the growing importance of stroke in developing countries, little is known of stroke burden in survivors. The authors investigated the prevalence of self-reported stroke, stroke-related disability, dependence and care-giver strain in Latin America (LA), China and India. METHODS: Cross-sectional surveys were conducted on individuals aged 65+ (n=15 022) living in specified catchment areas. Self-reported stroke diagnosis, disability, care needs and care giver burden were assessed using a standardised protocol. For those reporting stroke, the correlates of disability, dependence and care-giver burden were estimated at each site using Poisson or linear regression, and combined meta-analytically. RESULTS: The prevalence of self-reported stroke ranged between 6% and 9% across most LA sites and urban China, but was much lower in urban India (1.9%), and in rural sites in India (1.1%), China (1.6%) and Peru (2.7%). The proportion of stroke survivors needing care varied between 20% and 39% in LA sites but was higher in rural China (44%), urban China (54%) and rural India (73%). Comorbid dementia and depression were the main correlates of disability and dependence. CONCLUSION: The prevalence of stroke in urban LA and Chinese sites is nearly as high as in industrialised countries. High levels of disability and dependence in the other mainly rural and less-developed sites suggest underascertainment of less severe cases as one likely explanation for the lower prevalence in those settings. As the health transition proceeds, a further increase in numbers of older stroke survivors is to be anticipated. In addition to prevention, stroke rehabilitation and long-term care needs should be addressed.

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.

The association between common physical impairments and dementia in low and middle income countries, and, among people with dementia, their association with cognitive function and disability. A 10/66 Dementia Research Group population-based study.

OBJECTIVE: Chronic physical comorbidity is common in dementia. However, there is an absence of evidence to support good practice guidelines for attention to these problems. We aimed to study the extent of this comorbidity and its impact on cognitive function and disability in population-based studies in low and middle income countries, where chronic diseases and impairments are likely to be both common and undertreated. METHODS: A multicentre cross-sectional survey of all over 65 year old residents (n = 15 022) in 11 catchment areas in China, India, Cuba, Dominican Republic, Venezuela, Mexico and Peru. We estimated the prevalence of pain, incontinence, hearing and visual impairments, mobility impairment and undernutrition according to the presence of dementia and its severity, and, among those with dementia, the independent contribution of these impairments to cognitive function and disability, adjusting for age, gender, education and dementia severity. RESULTS: Incontinence, hearing impairment, mobility impairment and undernutrition were consistently linearly associated with the presence of dementia and its severity across regions. Among people with dementia, incontinence, hearing impairment and mobility impairment were independently associated with disability in all regions while the contributions of pain, visual impairment and undernutrition were inconsistent. Only hearing impairment made a notable independent contribution to cognitive impairment. CONCLUSIONS: There is an urgent need for clinical trials of the feasibility, efficacy and cost-effectiveness of regular physical health checks and remediation of identified pathologies, given the considerable comorbidity identified in our population based studies, and the strong evidence for independent impact upon functioning.

Predictors of mortality among elderly people living in a south Indian urban community; a 10/66 Dementia Research Group prospective population-based cohort study.

BACKGROUND: Eighty percent of deaths occur in low and middle income countries (LMIC), where chronic diseases are the leading cause. Most of these deaths are of older people, but there is little information on the extent, pattern and predictors of their mortality. We studied these among people aged 65 years and over living in urban catchment areas in Chennai, south India. METHODS: In a prospective population cohort study, 1005 participants were followed-up after three years. Baseline assessment included sociodemographic and socioeconomic characteristics, health behaviours, physical, mental and cognitive disorders, disability and subjective global health. RESULTS: At follow-up, 257 (25.6%) were not traced. Baseline characteristics were similar to the 748 whose vital status was ascertained; 154 (20.6%) had died. The mortality rate was 92.5/1,000 per annum for men and 51.0/1,000 per annum for women. Adjusting for age and sex, mortality was associated with older age, male sex, having no friends, physical inactivity, smaller arm circumference, dementia, depression, poor self-rated health and disability. A parsimonious model included, in order of aetiologic force, male sex, smaller arm circumference, age, disability, and dementia. The total population attributable risk fraction was 0.90. CONCLUSION: A balanced approach to prevention of chronic disease deaths requires some attention to proximal risk factors in older people. Smoking and obesity seem much less relevant than in younger people. Undernutrition is preventable. While dementia makes the largest contribution to disability and dependency, comorbidity is the rule, and more attention should be given to the chronic care needs of those affected, and their carers.

The predictive validity of the 10/66 dementia diagnosis in Chennai, India: a 3-year follow-up study of cases identified at baseline.

INTRODUCTION: The prevalence of dementia according to DSM-IV criteria tends to be very low in less developed settings. The 10/66 Dementia Research Group's cross-culturally validated diagnosis returns a considerably higher prevalence. Assessing the predictive validity of the 10/66 dementia diagnosis will assist in establishing the best criterion for estimating the population burden of dementia. METHODS: In a population-based study in Chennai, India, we aimed to follow-up after 3 years 75 people with 10/66 dementia and 193 with cognitive impairment but no dementia (CIND), reassessing diagnostic status, clinical severity, cognitive function, disability, and needs for care. RESULTS: We traced 54 people with dementia of whom 25 (46.3%) had died, double the mortality rate among those with CIND. Twenty-two of the 24 people with 10/66 dementia that were reexamined still met 10/66 dementia criteria. There was clear evidence of clinical progression and increased needs for care. Only one "case" had unambiguously improved. Cognitive function had deteriorated and disability increased to a much greater extent than among those with CIND. CONCLUSION: The strong predictive validity of the 10/66 dementia diagnosis is consistent with a lack of sensitivity of the DSM-IV criteria to mild-to-moderate cases, which may underestimate prevalence in less developed regions.