The Coyoacán Cohort Study: Design, Methodology, and Participants' Characteristics of a Mexican Study on Nutritional and Psychosocial Markers of Frailty.

BACKGROUND: "Frailty" has emerged as a condition associated with an increased risk of functional decline among the elderly, which may be differentiated from aging, disability, and co-morbidities. OBJECTIVE: The Mexican Study of Nutritional and Psychosocial Markers of Frailty among Community-Dwelling Elderly has emerged to help answer many questions about frailty among the older adults. This report presents the design of the study and baseline data of its participants. DESIGN: The "Coyoacan cohort" is a longitudinal observational study developed in Mexico City. PARTICIPANTS: A representative sample of 1,294 non-institutionalized men and women aged 70 years and older were randomly recruited to undergo a face-to-face interview and a comprehensive geriatric assessment (including clinical evaluations and blood samples) between 2008 and 2009. MEASUREMENTS: Data collected included socio-demographic and economic characteristics, medical history, oral health, drug use, cognitive function and mood, nutritional status, physical performance and functional status, physical activity, quality of life, social networks, and biological data. Frailty was defined as the presence of ≥3 of the following components: slowness, poor muscle strength, low physical activity, exhaustion and unintentional weight loss. RESULTS: A total of 1,124 participants completed the interview. The mean age was 79.5 ± 7.1 years, and 55.9% were female. Nine hundred and forty-five subjects completed the clinical evaluation and 743 blood samples were collected. The baseline prevalence of frailty was 14.1%. CONCLUSIONS: Understanding the medical, biological, and environmental factors that contribute to the phenomenon of frailty is the goal of the current research in the field.

Self-reported reading and writing skills in elderly who never attended school influence cognitive performances: results from the Coyoacán cohort study.

OBJECTIVES: Beyond the well-known effect of educational level on cognitive performances, the present study investigates the specific effect of literacy acquisition independently of education. DESIGN: A sample of 175 unschooled elderly participants was selected from a larger Mexican population-based cohort study. PARTICIPANTS: The sample of 175 subjects who never went to school was divided in two groups: 109 who never acquired literacy skills and 66 who declared having acquired reading and writing abilities. MEASUREMENTS: Cognitive performances on commonly used tests (mini mental state examination, Isaacs set test, free and cued selective reminding test and clock-drawing test) were compared between the two groups taking into account several potentially confounding factors. RESULTS: The participants with reading and writing skills performed better than their counterparts in most tests, even though no difference was observed for the Isaacs Set Test and the delayed recall of the free and cued selective reminding test. CONCLUSION: Writing and reading skills in elderly people with no formal education influence performances in very commonly used test. Not only educational level but also literacy acquisition should be taken into account when conducting cognitive assessment in very low educated elderly people.

Overweight and obesity as markers for the evaluation of disease risk in older adults.

OBJECTIVES: To explore disease risk through the measurement of BMI scores and waist circumferences in older Mexican adults with favorable health statuses and to determine how this risk is associated with sociodemographic characteristics. METHODS: Using data from the National Health and Nutrition Survey of 2006, we created a cross-sectional design and selected 878 participants (60 years or older) who had favorable health statuses. The demographic data, health status, body mass index (BMI), waist circumference (WC), and an estimation of disease risk (arterial hypertension, diabetes type 2, and metabolic syndrome) were obtained through the survey. RESULTS: The prevalence of overweight, obesity, and abdominal obesity were 42.1%, 29.7%, and 80.9%, respectively. Disease risks, which were classified as least, increased, high, or very high, were 14.7%, 17.5%, 38.7%, and 29.1%, respectively. We observed that younger age has a higher risk for disease and that this decreases as age increases until it becomes minimal. After controlling for some risk factors such as tobacco, alcohol, and physical activity, we observed that being female, younger, and married are all factors significantly associated with a high and very high risk for disease. On the other hand, being indigenous, having a low education level, living in a rural setting are all protective factors with a minimum disease risk. CONCLUSIONS: The prevalence rates of overweight, obesity, and abdominal obesity are high among older Mexican adults. We observed that as age increases, disease risk decreases, which also occurs with some lifestyle factors such as living in a rural setting, being indigenous, having a low education level, and being married.

Cognitive impairment and low physical activity are the components of frailty more strongly associated with disability.

OBJECTIVE: To determine the association of the five frailty criteria from the Cardiovascular Health Study, as well as cognitive impairment, with prevalent disability for the instrumental (IADL) and basic activities of daily living (ADL). DESIGN: Cross-sectional study of 475 community-dwelling subjects aged 70 and older, participating in the Mexican Study of Nutritional and Psychosocial Markers of Frailty. MEASUREMENTS: Six probable frailty criteria were considered: weight loss, poor endurance, low physical activity, slowness, weakness, and cognitive impairment. The association of each component of frailty for IADL and ADL disability as main outcomes was determined constructing multivariate logistic regression analyses. Final models were adjusted by socio-demographic factors and the presence of the other five frailty components as covariates. RESULTS: Mean age of participants was 78.1 (SD=6.2). The unadjusted results showed that each of the components of frailty, except weight loss, was associated with both IADL and ADL disability. However, after adjustment, only low physical activity [Odds ratio (OR) =3.27; 95% CI=1.56 to 6.85] and cognitive impairment (OR=2.06; 95% CI=1.04 to 4.06) remain independently associated with IADL disability. Regarding ADL disability, only a lower physical activity (OR=7.72; 95% CI=1.28 to 46.46) was associated with this outcome, whereas cognitive impairment was marginally associated but was not statistically significant (OR=5.45; 95% CI=0.91 to 32.57). CONCLUSIONS: Cognitive impairment and low physical activity are the main contributing factors of frailty phenotype to disability. Better understanding the independent contribution of each frailty subdimension to the different adverse-health outcomes may help to provide a more adequate management of frail elderly.

[Nutritional status of Guatemalan refugees below 6 years of age]. / Estado de nutrición de los refugiados guatemaltecos menores de seis años.

OBJECTIVE: To determine changes in the nutritional status of Guatemalan refugee children under six years of age, who lived in Mexico between 1982 and 1996, under various nutrition-related programs implemented during that period. MATERIAL AND METHODS: A comparative analysis of 4 cross-sectional anthropometric studies performed in Chiapas (1982, 1989), Quintana Roo (1989) and Campeche and Quintana Roo in 1996. Malnutrition prevalence by weight/age and height/age indicators was calculated. Odds ratio and 95% confidence intervals were estimated. The implemented programs to improve nutritional status and health conditions are described. RESULTS: In 1982, high rates of malnutrition and mortality prevailed among refugee children. In 1989 some had been transferred to Campeche and Quintana Roo and others stayed in Chiapas. Their situation had improved and remained so until 1996. CONCLUSIONS: The implemented programs were successful to control the emergency and prevent new crises. However they only managed to maintain similar conditions for the refugees as those which prevail among the Mexican indians.

[Morbidity characteristics among elderly Mexicans: an analysis of the 1988 National Health Survey]. / Características de la morbilidad en población mexicana de edad avanzada: un análisis de la Encuesta Nacional de Salud 1988.

OBJECTIVE: Based on the 1988 National Health Survey data base, a preliminary approach to an epidemiologic profile of the Mexican elderly is proposed. MATERIAL AND METHODS: This paper analyzes both reported prevalences of some of the principal health problems in Mexicans over 60 years of age and the relationship between selected morbidity, socio-demographic variables and impairment of daily living activities, stratified by age. RESULTS: Results show that: a) the panorama of reported morbidity among the Mexican elderly is a combination of multiple causes, b) socially defined groups present heterogeneous disease patterns, c) selected morbidity is strongly related to daily living activity impairments. CONCLUSIONS: This approach may be used to improve research on living and health conditions of the Mexican elderly.