Intrinsic capacity and its associations with incident dependence and mortality in 10/66 Dementia Research Group studies in Latin America, India, and China: A population-based cohort study.

BACKGROUND: The World Health Organization (WHO) has reframed health and healthcare for older people around achieving the goal of healthy ageing. The recent WHO Integrated Care for Older People (ICOPE) guidelines focus on maintaining intrinsic capacity, i.e., addressing declines in neuromusculoskeletal, vitality, sensory, cognitive, psychological, and continence domains, aiming to prevent or delay the onset of dependence. The target group with 1 or more declines in intrinsic capacity (DICs) is broad, and implementation may be challenging in less-resourced settings. We aimed to inform planning by assessing intrinsic capacity prevalence, by characterising the target group, and by validating the general approach-testing hypotheses that DIC was consistently associated with higher risks of incident dependence and death. METHODS AND FINDINGS: We conducted population-based cohort studies (baseline, 2003-2007) in urban sites in Cuba, Dominican Republic, Puerto Rico, and Venezuela, and rural and urban sites in Peru, Mexico, India, and China. Door-knocking identified eligible participants, aged 65 years and over and normally resident in each geographically defined catchment area. Sociodemographic, behaviour and lifestyle, health, and healthcare utilisation and cost questionnaires, and physical assessments were administered to all participants, with incident dependence and mortality ascertained 3 to 5 years later (2008-2010). In 12 sites in 8 countries, 17,031 participants were surveyed at baseline. Overall mean age was 74.2 years, range of means by site 71.3-76.3 years; 62.4% were female, range 53.4%-67.3%. At baseline, only 30% retained full capacity across all domains. The proportion retaining capacity fell sharply with increasing age, and declines affecting multiple domains were more common. Poverty, morbidity (particularly dementia, depression, and stroke), and disability were concentrated among those with DIC, although only 10% were frail, and a further 9% had needs for care. Hypertension and lifestyle risk factors for chronic disease, and healthcare utilisation and costs, were more evenly distributed in the population. In total, 15,901 participants were included in the mortality cohort (2,602 deaths/53,911 person-years of follow-up), and 12,939 participants in the dependence cohort (1,896 incident cases/38,320 person-years). One or more DICs strongly and independently predicted incident dependence (pooled adjusted subhazard ratio 1.91, 95% CI 1.69-2.17) and death (pooled adjusted hazard ratio 1.66, 95% CI 1.49-1.85). Relative risks were higher for those who were frail, but were also substantially elevated for the much larger sub-groups yet to become frail. Mortality was mainly concentrated in the frail and dependent sub-groups. The main limitations were potential for DIC exposure misclassification and attrition bias. CONCLUSIONS: In this study we observed a high prevalence of DICs, particularly in older age groups. Those affected had substantially increased risks of dependence and death. Most needs for care arose in those with DIC yet to become frail. Our findings provide some support for the strategy of optimising intrinsic capacity in pursuit of healthy ageing. Implementation at scale requires community-based screening and assessment, and a stepped-care intervention approach, with redefined roles for community healthcare workers and efforts to engage, train, and support them in these tasks. ICOPE might be usefully integrated into community programmes for detecting and case managing chronic diseases including hypertension and diabetes.

Reproductive period, endogenous estrogen exposure and dementia incidence among women in Latin America and China; A 10/66 population-based cohort study.

BACKGROUND: Exposure to endogenous estrogen may protect against dementia, but evidence remains equivocal. Such effects may be assessed more precisely in settings where exogenous estrogen administration is rare. We aimed to determine whether reproductive period (menarche to menopause), and other indicators of endogenous estrogen exposure are inversely associated with dementia incidence. METHODS: Population-based cohort studies of women aged 65 years and over in urban sites in Cuba, Dominican Republic, Puerto Rico and Venezuela, and rural and urban sites in Peru, Mexico and China. Sociodemographic and risk factor questionnaires were administered to all participants, including ages at menarche, birth of first child, and menopause, and parity, with ascertainment of incident 10/66 dementia, and mortality, three to five years later. RESULTS: 9,428 women participated at baseline, with 72-98% responding by site. The 'at risk' cohort comprised 8,466 dementia-free women. Mean age varied from 72.0 to 75.4 years, lower in rural than urban sites and in China than in Latin America. Mean parity was 4.1 (2.4-7.2 by site), generally higher in rural than urban sites. 6,854 women with baseline reproductive period data were followed up for 26,463 person years. There were 692 cases of incident dementia, and 895 dementia free deaths. Pooled meta-analysed fixed effects, per year, for reproductive period (Adjusted Sub-Hazard Ratio [ASHR] 1.001, 95% CI 0.988-1.015) did not support any association with dementia incidence, with no evidence for effect modification by APOE genotype. No association was observed between incident dementia and; ages at menarche, birth of first child, and menopause: nulliparity; or index of cumulative endogenous estrogen exposure. Greater parity was positively associated with incident dementia (ASHR 1.030, 95% CI 1.002-1.059, I2 = 0.0%). CONCLUSIONS: We found no evidence to support the theory that natural variation in cumulative exposure to endogenous oestrogens across the reproductive period influences dementia incidence in late life.

Frailty, dependency and mortality predictors in a cohort of Cuban older adults, 2003-2011.

INTRODUCTION: Population aging translates into more people with chronic non-communicable diseases, disability, frailty and dependency. The study of frailty--a clinical syndrome associated with an increased risk of falls, disability, hospitalization, institutionalization and death--is important to improve clinical practice and population health indicators. OBJECTIVES: In a cohort of older adults in Havana and Matanzas provinces, Cuba, estimate prevalence of frailty and its risk factors; determine incidence of dependency; estimate mortality risk and identify mortality predictors. METHODS: A prospective longitudinal study was conducted door to door, from June 2003 through July 2011, in a cohort of 2813 adults aged ≥65 years living in selected municipalities of Havana and Matanzas provinces; mean followup time was 4.1 years. Independent variables included demographics, behavioral risk factors and socioeconomic indicators, chronic non-communicable diseases (hypertension, stroke, dementia, depression, diabetes, anemia), number of comorbidities, and APOE ε4 genotype. Dependent variables were frailty, dependency and mortality. Criteria for frailty were slow walking speed, exhaustion, weight loss, low physical activity and cognitive decline. Prevalence and frailty risk were estimated by Poisson regression, while dependency and mortality risks and their predictors were determined using Cox regression. RESULTS: Frailty syndrome prevalence was 21.6% (CI 17.9%-23.8%) at baseline; it was positively associated with advanced age, anemia and presence of comorbidities (stroke, dementia, depression, three or more physically debilitating diseases). Male sex, higher educational level, married or partnered status, and more household amenities were inversely associated with frailty prevalence. In followup, dependency incidence was 33.1 per 1000 person-years (CI 29.1-37.6) and mortality was 55.1 per 1000 person-years. Advanced age, male sex, lower occupational status during productive years, dependency, frailty, dementia, depression, cerebrovascular disease and diabetes were all associated with higher risk of death. CONCLUSIONS: Given the challenge for developing countries presented by demographic and epidemiologic transition; the high prevalence in older adults of frailty syndrome, dependency and chronic non-communicable diseases; and the association of all these with higher mortality, attention should be targeted to older adults as a risk group. This should include greater social protection, age-appropriate health services, and modification and control of cardiovascular risk factors.

The prevalence, correlates and impact of anaemia among older people in Cuba, Dominican Republic, Mexico, Puerto Rico and Venezuela.

Anaemia among older people is increasingly recognized as a matter of public health concern. Data from low- and middle-income countries are sparse. We surveyed 10915 people aged 65 years and over (8423 with blood tests) in catchment areas in Cuba, Dominican Republic, Puerto Rico, Venezuela and Mexico, to assess prevalence and correlates of anaemia and impact on disability. Prevalence varied widely between sites, from 6·4% in rural Mexico to 9·2% in urban Mexico, 9·8% in Venezuela, 19·2% in Cuba, 32·1% in Puerto Rico and 37·3% in Dominican Republic. Prevalence was higher in men and increased with age, but sociodemographic composition did not account for prevalence differences between sites. Standardized morbidity ratios indicated a much higher prevalence in Cuba (173), Puerto Rico (280) and Dominican Republic (332) compared with USA National Health and National Examination Surveys. Anaemia was associated with undernutrition, physical impairments, and serum creatinine. There was an association with greater African admixture in Dominican Republic but not in Cuba. African admixture is therefore unlikely to fully explain the high prevalence in the Caribbean islands, which may also arise from environmental, possibly dietary factors. Given an important independent contribution of anaemia to disability, more research is needed to identify preventable and treatable causes.

Dementia and other chronic diseases in older adults in Havana and Matanzas: the 10/66 study in Cuba.

INTRODUCTION: Chronic non-communicable diseases are the leading cause of death worldwide, except in Sub-Saharan Africa. Nonetheless, one of these conditions, dementia, is the major contributor to disability-adjusted life years in people aged ≥60 years. Few epidemiological studies exist of the prevalence and impact of dementia and selected chronic diseases in older adults in Latin America. OBJECTIVE: Describe prevalence of dementia, other chronic vascular diseases and cardiovascular risk factors, as well as resulting disabilities and care needs generated in adults aged ≥65 years in Havana City and Matanzas provinces, Cuba. METHODS: The 10/66 study is a prospective longitudinal study involving a cohort of 3015 adults aged ≥65 years in municipalities of Havana City and Matanzas provinces, divided into two phases: a cross-sectional door-to-door study conducted in 2003-2006, and a follow-up and assessment phase in 2007-2010. This article reports findings from the first phase. Hypertension diagnosis was based on criteria from the International Society for Hypertension; diabetes mellitus on American Diabetes Association criteria; stroke according to WHO definitions; and dementia according to criteria of the American Psychiatric Society's Diagnostic and Statistical Manual of Mental Disorders DSM-IV and the 10/66 International Dementia Research Group. Ischemic heart disease was defined by self-report of previous physician diagnosis. Study variables included age, sex, educational level, substance use (alcohol, tobacco) and dietary habits. A structured physical and neurological exam, including blood pressure measurement, was performed on all participants. Laboratory tests included complete blood count, fasting blood glucose, total cholesterol and lipoprotein fractions, triglycerides and apolipoprotein E genotype. Prevalence and standardized morbidity ratios (crude and adjusted) were calculated for chronic diseases studied with 95% confidence intervals, using a Poisson regression model and indirect standardization. RESULTS: The study assessed 2944 older adults (response rate 97.6%) and found high prevalence of vascular risk factors and of chronic non-communicable diseases: hypertension 73.0% (95% CI 71.4-74.7), diabetes mellitus 24.8% (95% CI 22.9-26.5), ischemic heart disease 14.1% (95% CI 12.9-15.4), dementia 10.8% (95% CI 9.7-12.0) and stroke 7.8% (95% CI 6.9-8.8). The majority of participants (85%) had more than one cardiovascular risk factor. The main cause of disability and dependency in the study population was dementia. CONCLUSION: The high prevalence of chronic diseases observed in the elderly--with the consequent morbidity, disability and dependency--highlights the need for prevention, early diagnosis and risk factor control, particularly given the demographic and epidemiologic transition faced by Cuba and other developing countries.

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.

Prevalence of stroke and associated risk factors in older adults in Havana City and Matanzas Provinces, Cuba (10/66 population-based study).

INTRODUCTION: Cerebrovascular disease (CVD) is the third cause of death and second cause of disability and dementia in adults aged>or=65 years worldwide. The few epidemiological studies of stroke in Latin America generally report lower prevalence and different patterns than developed countries. OBJECTIVE: Estimate the prevalence of stroke and associated risk factors in adults aged>or=65 years in Havana City and Matanzas provinces, Cuba. METHODS: Single phase, cross-sectional, door-to-door study of 3015 adults aged>or=65 years in selected municipalities of Havana City and Matanzas provinces. Variables studied were age, sex, educational level, and self-report and description of chronic disease (stroke, heart attack, angina, and diabetes mellitus), substance use (alcohol, tobacco), and dietary habits. Respondents were given a structured physical and neurological exam, and blood pressure was measured. Laboratory tests comprised complete blood count, fasting glucose, total cholesterol and fractions, triglycerides, and apolipoprotein E (APOE) genotype. Diagnosis of stroke was based on the World Health Organization's definition. Stroke prevalence ratios (crude and adjusted), with 95% confidence intervals (CI), were calculated for the variables studied using a Poisson regression model. Risk association was analyzed using multiple logistic regression for dichotomous responses. RESULTS: Assessments were made of 2944 older adults (97.6% response rate). Prevalence of stroke was 7.8% (95% CI 6.9-8.8), and was higher in men. The risk profile for this population group included history of hypertension (OR 2.8; 95% CI 2.0-4.0), low HDL cholesterol (OR 2.6; 95% CI 1.7-3.9), male sex (OR 1.7; 95% CI 1.2-2.5), anemia (OR 1.6; 95% CI 1.1-2.5), history of ischemic heart disease (OR 1.5; 95% CI 1.0-2.3), carrier of one or two apolipoprotein E4 genotype (APOE E4) alleles (OR 1.4; 95% CI 1.0-2.0), and advanced age (OR 1.3; 95% CI 1.1-1.9). CONCLUSIONS: Stroke prevalence in this study is similar to that reported for Europe and North America, and higher than that observed in other Latin American countries. The risk profile identified includes classic risk factors plus anemia and APOE E genotype.

Prevalence of dementia in Latin America, India, and China: a population-based cross-sectional survey.

BACKGROUND: Studies have suggested that the prevalence of dementia is lower in developing than in developed regions. We investigated the prevalence and severity of dementia in sites in low-income and middle-income countries according to two definitions of dementia diagnosis. METHODS: We undertook one-phase cross-sectional surveys of all residents aged 65 years and older (n=14 960) in 11 sites in seven low-income and middle-income countries (China, India, Cuba, Dominican Republic, Venezuela, Mexico, and Peru). Dementia diagnosis was made according to the culturally and educationally sensitive 10/66 dementia diagnostic algorithm, which had been prevalidated in 25 Latin American, Asian, and African centres; and by computerised application of the dementia criterion from the Diagnostic and Statistical Manual of Mental Disorders (DSM IV). We also compared prevalence of DSM-IV dementia in each of the study sites with that from estimates in European studies. FINDINGS: The prevalence of DSM-IV dementia varied widely, from 0.3% (95% CI 0.1-0.5) in rural India to 6.3% (5.0-7.7) in Cuba. After standardisation for age and sex, DSM-IV prevalence in urban Latin American sites was four-fifths of that in Europe (standardised morbidity ratio 80 [95% CI 70-91]), but in China the prevalence was only half (56 [32-91] in rural China), and in India and rural Latin America a quarter or less of the European prevalence (18 [5-34] in rural India). 10/66 dementia prevalence was higher than that of DSM-IV dementia, and more consistent across sites, varying between 5.6% (95% CI 4.2-7.0) in rural China and 11.7% (10.3-13.1) in the Dominican Republic. The validity of the 847 of 1345 cases of 10/66 dementia not confirmed by DSM-IV was supported by high levels of associated disability (mean WHO Disability Assessment Schedule II score 33.7 [SD 28.6]). INTERPRETATION: As compared with the 10/66 dementia algorithm, the DSM-IV dementia criterion might underestimate dementia prevalence, especially in regions with low awareness of this emerging public-health problem.