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

Low 25-Hydroxyvitamin D [25(OH)D] Levels as a Predictor of Depressive Symptoms: Evidence from Community-Dwelling Older Adults Population in Mexico City

OBJECTIVE

The purpose of this study was to assess the association between serum 25-hydroxyvitamin D [25(OH)D] levels and depressive symptoms in Mexican older adults 70 years and older.

METHODS

A total of 326 adults aged 70 or older from Coyoacán Cohort Study were included in this study. The depressive symptoms were assessing by Center for Epidemiologic Studies Depression Scale (CES-D) and serum 25-hydroxyvitamin D [25(OH)D] levels were measured by commercially available enzyme-linked immunosorbent assay (ELISA).

RESULTS

Overall, the prevalence of depressive symptoms was 36.5%. The mean age was 79 years, and 53.4% were women. The total serum 25-hydroxyvitamin D [25(OH)D] levels were lower in older adults with depressive symptoms when compared with older adults without depressive symptoms (p = .006). Logistic regression models showed a significant association between low serum 25(OH)D levels and depressive symptoms even after adjusting for potential confounders (OR = 2.453; 95% CI:1.218-4.939; p = .012). In addition, linear regression model to predict the effect of 25-hydroxyvitamin D [25(OH)D] levels on the CES-D score as a continuous variable, was statistically significant [F(1,324) = 8.54, p = .004], and the R-squared value was .026, indicating that this regression model explains 2.6% of the change in the CES-D score.

CONCLUSION

These results suggest that older Mexican adults with lower serum 25-hydroxyvitamin D [25(OH)D] levels are at higher risk of presenting depressive symptoms.

Frailty index and ten oral conditions in the Coyoacan cohort study: A cross-sectional analysis

OBJECTIVES

To analyse the relationship between the Frailty Index and 10 oral conditions controlling for nutritional status among Mexican community-dwelling older people.

BACKGROUND

Studies suggest that the association between frailty and oral conditions are mediated by nutrition.

MATERIALS AND METHODS

This cross-sectional analysis includes 487 community-dwelling men and women aged ≥70 years old. Interview and clinical examinations were performed at participants' homes. Objective (number of natural teeth, root remnants, dental condition, utilisation and functionality of removable dental prostheses and periodontitis) and subjective (utilisation of dental services, self-rated oral health, chewing difficulties and xerostomia) oral variables were collected by trained personnel. The Frailty Index was calculated considering 35 deficits. Nutritional status measured with the Mini-Nutritional assessment (MNA), age, sex, education, and marital status were included as covariates. We fitted 11 multivariate generalised linear models (one for each oral condition), assuming gamma distribution for Frailty Index as the outcome.

RESULTS

Participants average age was 78.1 years, 52.1% were women. We observed a higher Frailty Index among those rating their oral health as worse than others their age (5.1%), reporting chewing difficulties often (4.9%) and fairly and very often (7.0%), and xerostomia (4.8%). Age, gender and MNA were consistently associated with the Frailty Index.

CONCLUSION

Subjective oral conditions are compatible with the Frailty Index after controlling for older people's nutritional status and covariates.

Clinical and metabolomic predictors of regression to normoglycemia in a population at intermediate cardiometabolic risk

Background

Impaired fasting glucose (IFG) is a prevalent and potentially reversible intermediate stage leading to type 2 diabetes that increases risk for cardiometabolic complications. The identification of clinical and molecular factors associated with the reversal, or regression, from IFG to a normoglycemia state would enable more efficient cardiovascular risk reduction strategies. The aim of this study was to identify clinical and biological predictors of regression to normoglycemia in a non-European population characterized by high rates of type 2 diabetes.

Methods

We conducted a prospective, population-based study among 9637 Mexican individuals using clinical features and plasma metabolites. Among them, 491 subjects were classified as IFG, defined as fasting glucose between 100 and 125 mg/dL at baseline. Regression to normoglycemia was defined by fasting glucose less than 100 mg/dL in the follow-up visit. Plasma metabolites were profiled by Nuclear Magnetic Resonance. Multivariable cox regression models were used to examine the associations of clinical and metabolomic factors with regression to normoglycemia. We assessed the predictive capability of models that included clinical factors alone and models that included clinical factors and prioritized metabolites.

Results

During a median follow-up period of 2.5 years, 22.6% of participants (n = 111) regressed to normoglycemia, and 29.5% progressed to type 2 diabetes (n = 145). The multivariate adjusted relative risk of regression to normoglycemia was 1.10 (95% confidence interval [CI] 1.25 to 1.32) per 10 years of age increase, 0.94 (95% CI 0.91–0.98) per 1 SD increase in BMI, and 0.91 (95% CI 0.88–0.95) per 1 SD increase in fasting glucose. A model including information from age, fasting glucose, and BMI showed a good prediction of regression to normoglycemia (AUC = 0.73 (95% CI 0.66–0.78). The improvement after adding information from prioritized metabolites (TG in large HDL, albumin, and citrate) was non-significant (AUC = 0.74 (95% CI 0.68–0.80), p value = 0.485).

Conclusion

In individuals with IFG, information from three clinical variables easily obtained in the clinical setting showed a good prediction of regression to normoglycemia beyond metabolomic features. Our findings can serve to inform and design future cardiovascular prevention strategies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01246-1.

PTPN22 gene functional polymorphism (rs2476601) in older adults with frailty syndrome

The frailty syndrome is a common clinical marker of vulnerability in older adults conducive to an overall decline in inflammatory stress responsiveness; yet little is known about the genetic risk factors for frailty in elderly. Our aim was to investigate the association between the rs2476601 polymorphism in PTPN22 gene and susceptibility to frailty in Mexican older adults. Data included 630 subjects 70 and older from The Coyoacán cohort, classified as frail, pre-frail, and non-frail following Fried's criteria. Sociodemographic and clinical characteristics were compared between groups at baseline and after a multivariate analysis. The rs2476601 polymorphism was genotyped by TaqMan genotyping assay using real-time PCR and genotype frequencies were determined for each frailty phenotype in all participants and subsets by age range. Genetic association was examined using stratified and interaction analyses adjusting for age, sex and variables selected in the multivariate analysis. Disability for day-life activities, depression and cognitive impairment were associated with the risk of pre-frailty and frailty at baseline and after adjustment. Carrying the T allele increased significantly the risk of frailty in patients 76 and older (OR 5.64, 95% CI 4.112-7.165) and decreased the risk of pre-frailty under no clinical signs of depression (OR 0.53; 95% CI 0.17-1.71). The PTPN22 polymorphism, rs2476601, could be a genetic risk factor for frailty as subject to quality of life. This is the first study analyzing such relationship in Mexican older adults. Confirming these findings requires additional association studies on wider age ranges in populations of older adults with frailty syndrome.

Cerebral Vascular Reactivity in Frail Older Adults with Vascular Cognitive Impairment

Background: Frailty, a state of increased vulnerability, could play a role in the progression of vascular dementia. We aim to describe the changes in cerebrovascular reactivity of older adults with frailty and vascular-type mild cognitive impairment (MCIv). Methods: This was a cross-sectional study. A comprehensive geriatric assessment, neuropsychological evaluation, and transcranial Doppler ultrasound (TCD) was performed on 180 participants who were allocated into four groups: healthy (n = 74), frail (n = 40), MCIv (n = 35), and mixed (frail + MCIv) (n = 31). ANOVA and Kruskal–Wallis tests were used for the analysis of continuous variables with and without normal distribution. Multinomial logistic regression was constructed to identify associated covariates. Results: Subjects in the mixed group, compared to healthy group, were older (75.0 ± 5.9 vs 70.3 ± 5.9 years; p < 0.001), showed lower education (9.3 ± 6.4 vs 12.2 ± 4.0 years; p = 0.054), greater frequency of diabetes (42% vs 12%; p = 0.005), worse cognitive performance (z = −0.81 ± 0.94), and reduced left medial-cerebral artery cerebrovascular reactivity (0.43 ± 0.42 cm/s). The mixed group was associated with age (odds ratio (OR) 1.16, 95% Confidence Interval (CI) = 1.06–1.27; p < 0.001), diabetes (OR 6.28, 1.81–21.84; p = 0.004), and Geriatric Depression Scale (GDS) score (OR 1.34, 95% CI = 1.09–1.67; p = 0.007). Conclusions: Frailty among older adults was associated with worse cognitive performance, diabetes, and decreased cerebral blood flow.

Development and validation of a predictive model for incident type 2 diabetes in middle-aged Mexican adults: the metabolic syndrome cohort

BACKGROUND

Type 2 diabetes mellitus (T2D) is a leading cause of morbidity and mortality in Mexico. Here, we aimed to report incidence rates (IR) of type 2 diabetes in middle-aged apparently-healthy Mexican adults, identify risk factors associated to ID and develop a predictive model for ID in a high-risk population.

METHODS

Prospective 3-year observational cohort, comprised of apparently-healthy adults from urban settings of central Mexico in whom demographic, anthropometric and biochemical data was collected. We evaluated risk factors for ID using Cox proportional hazard regression and developed predictive models for ID.

RESULTS

We included 7636 participants of whom 6144 completed follow-up. We observed 331 ID cases (IR: 21.9 per 1000 person-years, 95%CI 21.37-22.47). Risk factors for ID included family history of diabetes, age, abdominal obesity, waist-height ratio, impaired fasting glucose (IFG), HOMA2-IR and metabolic syndrome. Early-onset ID was also high (IR 14.77 per 1000 person-years, 95%CI 14.21-15.35), and risk factors included HOMA-IR and IFG. Our ID predictive model included age, hypertriglyceridemia, IFG, hypertension and abdominal obesity as predictors (Dxy = 0.487, c-statistic = 0.741) and had higher predictive accuracy compared to FINDRISC and Cambridge risk scores.

CONCLUSIONS

ID in apparently healthy middle-aged Mexican adults is currently at an alarming rate. The constructed models can be implemented to predict diabetes risk and represent the largest prospective effort for the study metabolic diseases in Latin-American population.

Comparison of quality of life among community-dwelling older adults with the frailty phenotype

PURPOSE

To compare the perception of the quality of life (QOL) of community-dwelling older adults with the phenotype of frailty.

METHODS

Cross-sectional analysis of baseline data of the "Cohort of Obesity, Sarcopenia and Frailty of Mexican Older Adults" (COSFOMA). Operationalization of frailty was carried out using the phenotype as follows: weight loss, self-report of exhaustion, low physical activity, slow gait, and weakness. QOL was measured using two scales: World Health Organization Quality of Life of Older Adults (WHOQOL-OLD), which is a specific instrument for the elderly population, and Short Form-36 Health Survey (SF-36), a generic instrument to evaluate the QOL related to health. One-way analyses of variance were conducted to assess the differences among the three phenotypes of frailty and QOL perception.

RESULTS

There were 1252 older adult participants who were analyzed; 11.2% (n = 140) had frailty, 50.3% (n = 630) pre-frailty and 38.5% (n = 482) were not frail. The mean (±SD) total score of the WHOQOL-OLD according to the phenotype of frailty was 60.3 (13.9) for those with frailty, 67.4 (12.7) pre-frailty and 72.4 (11.2) not frail (ANOVA, p < 0.001). The mean (±SD) of the SF-36 of the physical and mental component measures the sum, 38.9 (9.9) and 41.9 (11.3) with frailty, 45.7 (9.1) and 46.6 (9.8) pre-frailty, and 49.6 (7.3) and 49.4 (7.9) not frail, respectively (ANOVA, p < 0.001).

CONCLUSIONS

Frailty is observed in 1/10 community-dwelling older adults. Those with frailty and pre-frailty had a lower perception of QOL compared with those who were not frail.

Risk factors for urinary incontinence among postmenopausal Mexican women

INTRODUCTION AND HYPOTHESIS

Previous studies of racial/ethnic variation in urinary incontinence (UI) suggest that population-specific studies of UI risk factors are needed to develop appropriate public health recommendations. We assessed UI risk factors among postmenopausal Mexican women enrolled in the Mexican Teachers' Cohort.

METHODS

We conducted a cross-sectional study among 15,296 postmenopausal women who completed the 2008 questionnaire. UI cases were women who reported experiencing UI during menopause. Self-reported potential UI risk factors included age, reproductive variables, smoking status, adiposity, and several health conditions. We estimated multivariate-adjusted odds ratios (ORs) and 95 % confidence intervals (CIs) for UI using multivariable logistic regression.

RESULTS

Among these postmenopausal women, the prevalence of UI was 14 %. Odds of UI were higher among women with ≥4 children vs nulliparous women (OR 1.43, 95 % CI 1.04-1.96) or body mass index (BMI) ≥30 vs <22 kg/m² (OR 2.00, 95 % CI: 1.55-2.57). Age at first birth <20 vs 20-24 years, past or current vs never smoking, larger waist-to-hip ratio, and history of asthma, high blood pressure, or diabetes were also associated with higher odds of UI (OR 1.2-1.3). We found a trend of lower odds of UI with older age.

CONCLUSIONS

Our data suggest that information about UI and UI prevention strategies might be particularly useful for Mexican postmenopausal women with 4 or more children or higher BMI. Further studies with longitudinal UI data, in addition to data on UI severity and subtype, are needed to provide more specific information about UI risk factors to Mexican women.

Frailty prevalence and associated factors in the Mexican health and aging study: A comparison of the frailty index and the phenotype

BACKGROUND

Frailty is a relatively new phenomenon described mainly in the older population. There are a number of different tools that aim at categorizing an older adult as frail. Two of the main tools for this purpose are the Fried's frailty phenotype (FFP) and the frailty index (FI). The aim of this report is to determine the prevalence of frailty and associated factors using both FFP and the FI.

METHODS

Secondary analysis of 1108 individuals aged 60 or older is participating in the third (2012) wave from the Mexican Health and Aging Study (MHAS). The FFP and the FI were constructed and a set of variables from different domains were used to explore associations. Domains included were: socio-demographic, health-related, and psychological factors. Regarding prevalence, concordance was tested with a kappa statistic. To test significant associations when classifying with each of the tools, multiple logistic regression models were fitted.

RESULTS

Mean (SD) age was 69.8 (7.6) years, and 54.6% (n=606) were women. The prevalence of frailty with FFP was 24.9% (n=276) while with FI 27.5% (n=305). Kappa statistics for concordance between tools was 0.34 (p<0.001). Age, years in school, number of past days in bed due to health problems, number of times that consulted a physician last year for health problems, having smoked in the past, and life satisfaction were associated with frailty when using any of the tools.

CONCLUSIONS

There is a persistent heterogeneity on how frailty is measured that should be addressed in future research.