Frailty was associated with atmospheric NO2 levels: a geospatial approach.

BACKGROUND: Recent evidence has linked air pollution with frailty, yet little is known about the role of NO2 in this association. Our aim was to assess the association between frailty and NO2 air concentrations in Mexican older adults. METHODS: We used georeferenced data from the population-based Nutrition and Health Survey in Mexico (NHNS) 2021, representative of national and subnational regions, to measure a frailty index based on 31 health deficits in adults aged 50 and over. Air pollution due to NO2 concentrations was estimated from satellite images validated with data from surface-level stations. Maps were produced using Jensen's Natural break method. The association of frailty and NO2 concentrations was measured using the frailty index (multivariate fractional response logit regression) and a frailty binary variable (FI ≥ 0.36, multivariate logit regression). RESULTS: There was a positive and significant association of the frailty index with the NO2 concentrations, adjusting for age, sex, urban/ rural area, years of education, socio-economic status, living arrangement, particulate matter smaller than 2.5 microns, and indoor pollution. For each standard deviation increase of NO2 concentrations measured ten years before the survey, the odds of being frail were 15% higher, and the frailty index was 14.5% higher. The fraction of frailty attributable to NO2 exposure ranged from 1.8 to 23.5% according to different scenarios. CONCLUSION: Frailty was positively associated with exposure to NO2 concentrations. Mapping frailty and its associated factors like NO2 air concentrations can contribute to the design of targeted pro-healthy aging policies.

Predictors of Frailty Transitions in Mexican Older Adults.

BACKGROUND: Frailty is a dynamic state in older adults. Current evidence, mostly in high-income countries, found that improving frailty is more likely in mild states (prefrailty). We aimed to determine the probability of frailty transitions and their predictors. METHODS: Participants were adults aged 50 years or over from the Study on Global Ageing and Adult Health in Mexico during 4 waves (2009, 2014, 2017, and 2021). We defined frailty with the frailty phenotype and we used multinomial logistic models to estimate the probabilities of frailty transitions and determine their predictors. RESULTS: For the 3 analyzed periods (2009-2014, 2014-2017, and 2017-2021), transition probabilities from frail to robust were higher for the younger age group (50-59 years) at 0.20, 0.26, and 0.20, and lower for the older age group (≥80 years), 0.03, 0.08 and 0.04. Transitioning from prefrail to robust had probabilities of 0.38, 0.37, and 0.35, for the younger age group, and 0.09, 0.18, and 0.10, for the older age group. The probabilities of transitioning to frail and to death were lower for the younger age group and for the robust at baseline; but higher for the older age group and for the frail at baseline. We identified age, disability, and diabetes as the most significant predictors of frailty transitions. CONCLUSIONS: These findings show that frailty has a dynamic nature and that a significant proportion of prefrail and frail individuals can recover to a robust or prefrail state. They also emphasize that prefrailty should be the focus of interventions.

Mediator effect of caregiver burden on the association between disability and quality of life among older adults.

OBJECTIVE: To estimate the association of disability and qual-ity of life considering the potential mediating role of caregiver burden among a sample of older Mexican adults and their caregivers. MATERIALS AND METHODS: Cross-sectional study with 93 dyads (elderly/caregivers) conducted in 2018 in five localities (urban and rural) of the State of Mexico. The quality of life (QoL) was determined using the WHOQoL (WHO Quality of Life) instrument. Disability was measured by assessing the basic activities of daily living (BADL), and the caregiver burden was evaluated by the Zarit Burden Interview (ZBI). RESULTS: The results showed that BADL disability is associated with a lower QoL (total effect: -14.3; 95%CI: -20.2,-8.4) and that a significant proportion of this associa-tion can be attributable to caregiver burden (25.0%; 95%CI: 17.9,43.2). CONCLUSIONS: Our findings show the need for designing effective interventions that prevent or ameliorate the adverse effects of caregiver burden.

Inflammation and central adiposity as mediators of depression and uncontrolled diabetes in the study on global AGEing and adult health (SAGE).

OBJECTIVES: Diabetes and depression are commonly present in the same individuals, suggesting the possibility of underlying shared physiological processes. Inflammation, as assessed with the biomarker C-reactive protein (CRP), has not consistently explained the observed relationship between diabetes and depression, although both are associated with inflammation and share proposed inflammatory mechanisms. Central adiposity has also been associated with both conditions, potentially by causing increased inflammation. This study uses the World Health Organization's Study on global AGEing and adult health (SAGE) Mexico Wave 1 biomarker data (n = 1831) to evaluate if inflammation and central adiposity mediate the relationship between depression and diabetes. METHODS: Depression was estimated using a behavior-based diagnostic algorithm, inflammation using venous dried blood spot (DBS) CRP, central adiposity using waist-to-height ratio (WHtR), and uncontrolled diabetes using venous DBS-glycated hemoglobin (HbA1c). RESULTS: The association between depression and uncontrolled diabetes was partially mediated by CRP before but not after WHtR was considered. When WHtR was added to the model, it partially mediated the relationship between diabetes and depression while fully mediating the relationship between depression and CRP. CONCLUSIONS: These findings suggest that central adiposity may be a more significant mediator between diabetes and depression than inflammation and account for the relationship between these disorders and inflammation. Depression may cause an increase in central adiposity, which then may lead to diabetes, but the increase in known systemic inflammatory pathways caused by central adiposity may not be the key pathological mechanism.

Neighborhood features and depression in Mexican older adults: A longitudinal analysis based on the study on global AGEing and adult health (SAGE), waves 1 and 2 (2009-2014).

A growing body of literature shows that neighborhood characteristics influence older adults' mental health. Therefore, the aim of this study was to examine the association between structural and social characteristics of the neighborhood, and depression in Mexican older adults. A longitudinal study was conducted based on waves 1 (2009-2010) and 2 (2014) of the Mexican sample from the Study on global AGEing and adult health (SAGE). A street-network buffer around each participant's household was used to define neighborhood, so that built environment and social characteristics were assessed within it. Depression was ascertained by using an algorithm based on the Composite International Diagnostic Interview. In the analysis, multilevel logistic regression models were constructed separately for each built and social environments measurement, adjusted for socioeconomic, demographic and health-related covariates, and stratified by area of residence (urban versus rural). The results showed that a length of space between 15-45 meters restricted to vehicles was significantly associated with a lower risk of depression in older adults from the urban area (OR: 0.44; IC 95% 0.23-0.83) and the protective association appeared to be larger with increasing space with this restriction, although it lacked significance. Contrarily, the built environment measures were not predictive of depression in the rural setting. On the other hand, none of the variables from the social environment had a significant association, although safety appeared to behave as a risk factor in the overall (OR: 1.48; CI 95% 0.96-2.30; p = 0.08) and rural (OR: 3.44; CI 95% 0.95-12.45; p = 0.06) samples, as it reached marginal significance. Research about neighborhood effects on older adults' mental health is an emergent field that has shown that depression might be treated not only from the individual-level, but also from the neighborhood-level. Additionally, further research is needed, especially in low- and middle-income countries, to help guide neighborhood policies.

Work status, retirement, and depression in older adults: An analysis of six countries based on the Study on Global Ageing and Adult Health (SAGE).

The aim of the present study was to analyse the association between the occurrence of a major depressive episode among older adults and work status in low- and medium-income countries. A cross-sectional study was conducted with people 60 years of age and older from the six countries (Mexico, India, China, Russian Federation, Ghana and South Africa) included in the Study on Global Ageing and Adult Health (SAGE) and who participated in its first wave (2009-2010). The occurrence of a major depressive episode (MDE) over the previous 12 months was determined based on an adaptation of the ICD-10 diagnostic criteria. The association between current work status and the presence of an MDE was estimated using binary logistic regression models with country-level fixed effects, and interaction terms between the country and work status. Results showed the odds of presenting an MDE were lower for older adults who were retired with a pension than for those who were currently working, although this protective association was observed only for men in China (OR=0.23; CI 95%:0.08-0.70) and Ghana (OR=0.25; CI 95%:0.07-0.95) and for women in India (OR=0.05; CI 95%:0.01-0.51) and South Africa (OR=0.19; CI 95%:0.04-0.97). For women, being a homemaker also showed a protective association in South Africa (OR=0.09; CI95%:0.01-0.66) and Mexico (OR=0.32; CI95%:0.14-0.76). In the case of being retired without a pension, no significant association was found in any country. The previous indicates that retirement with pension has a protective association with MDE only for men in China and Ghana and women in India and South Africa. The heterogeneity of this association reflects cultural and socioeconomic differences between the analysed countries.

Multidimensional social support is associated with healthcare utilization among older Mexican adults.

In this study, we aimed to estimate the association between social support and healthcare utilization among older Mexican adults. We conducted a prospective study with 4027 older adults aged 65-74 in rural areas in seven Mexican states. Data were collected at baseline (2007) and 14 months later (2009). Healthcare utilization was defined as number of visits to a physician for preventive or curative purposes in the last 6 months. Multidimensional social support was operationalized into two components: structural (living arrangements, marital status and network size) and functional (perceived availability of support; and perceived support across emotional, instrumental, economic and information domains). Mixed-effects regression models were used to estimate the probability of healthcare use and to examine the association between social support and the number of visits to a physician. Results showed that perceived availability of social support was associated with the probability of visits to a physician (OR 1.44; p < .01). Meanwhile, the following domains of functional component of social support were associated with the probability of visits to a physician: instrumental (OR 1.55; p < .01), economic (OR 1.19; p = .03) and informational (OR 1.39; p < .01); and also with the number of visits to a physician: instrumental (e ß  = 1.27; p < .01), economic (e ß  = 1.14; p = .01) and informational (e ß  = 1.12; p < .10). Our findings suggest that a significant association exists between social support, measured from a multidimensional viewpoint, and healthcare utilization, in which greater social support was related to a greater extent of use of health services.

Exposure to air pollution and tobacco smoking and their combined effects on depression in six low- and middle-income countries.

BackgroundLittle is known about the joint mental health effects of air pollution and tobacco smoking in low- and middle-income countries.AimsTo investigate the effects of exposure to ambient fine particulate matter pollution (PM2.5) and smoking and their combined (interactive) effects on depression.MethodMultilevel logistic regression analysis of baseline data of a prospective cohort study (n = 41 785). The 3-year average concentrations of PM2.5 were estimated using US National Aeronautics and Space Administration satellite data, and depression was diagnosed using a standardised questionnaire. Three-level logistic regression models were applied to examine the associations with depression.ResultsThe odds ratio (OR) for depression was 1.09 (95% C11.01-1.17) per 10 µg/m3 increase in ambient PM2.5, and the association remained after adjusting for potential confounding factors (adjusted OR = 1.10, 95% CI 1.02-1.19). Tobacco smoking (smoking status, frequency, duration and amount) was also significantly associated with depression. There appeared to be a synergistic interaction between ambient PM2.5 and smoking on depression in the additive model, but the interaction was not statistically significant in the multiplicative model.ConclusionsOur study suggests that exposure to ambient PM2.5 may increase the risk of depression, and smoking may enhance this effect.

The association between social support and cognitive function in Mexican adults aged 50 and older.

Social support networks are crucial for the health of older adults; however, personal characteristics and time of life may diminish the protective effect of social support. OBJECTIVE: to determine if the presence of social support networks were associated with cognitive impairment among Mexican adults aged 50 or older and if this relationship was different based on age. METHOD: This study analyzed data from the National Representation Survey performed in Mexico, Study on Global Ageing (SAGE) wave 1. Cognitive function was evaluated by a standardized test, social support was evaluated through latent class analysis (LCA). The LCA was run to obtain three subgroups of different Social Support Levels (SSL): low, medium, and high. Logistic regression models, stratified by age, were performed to analyze the association between SSL and cognitive function. RESULTS: For respondents ages 71-80 y/o, there was an inverse relationship with cognitive impairment for those with medium (OR 0.23, p=0.020) and high (OR 0.07, p=0.000) SSL in comparison with low SSL. While social support helped to improve cognitive function in older adults aged 71-80, this same association was not observed in adults of other ages. Those younger than 70 y/o may not need such a strong support network as a result of being more self-sufficient. After 80, social networks were not enough to help diminish the negative impact of cognitive impairment. CONCLUSION: Social support could improve the cognitive function of adults ages 71 and 80; suggesting there could be a window of opportunity to improve cognitive functioning for this group.

Income inequality, socioeconomic deprivation and depressive symptoms among older adults in Mexico.

OBJECTIVE: Depression is the second most common mental disorder in older adults (OA) worldwide. The ways in which depression is influenced by the social determinants of health - specifically, by socioeconomic deprivation, income inequality and social capital - have been analyzed with only partially conclusive results thus far. The objective of our study was to estimate the association of income inequality and socioeconomic deprivation at the locality, municipal and state levels with the prevalence of depressive symptoms among OA in Mexico. METHODS: Cross-sectional study based on a nationally representative sample of 8,874 OA aged 60 and over. We applied the brief seven-item version of the Center for Epidemiologic Studies Depression Scale (CES-D) to determine the presence of depressive symptoms. Additionally, to select the principal context variables, we used the Deprivation Index of the National Population Council of Mexico at the locality, municipal and state levels, and the Gini Index at the municipal and state levels. Finally, we estimated the association of income inequality and socioeconomic deprivation with the presence of depressive symptoms using a multilevel logistic regression model. RESULTS: Socioeconomic deprivation at the locality (OR = 1.28; p<0.10) and municipal levels (OR = 1.16; p<0.01) correlated significantly with the presence of depressive symptoms, while income inequality did not. CONCLUSIONS: The results of our study confirm that the social determinants of health are relevant to the mental health of OA. Further research is required, however, to identify which are the specific socioeconomic deprivation components at the locality and municipal levels that correlate with depression in this population group.

Effect of the conditional cash transfer program Oportunidades on vaccination coverage in older Mexican people.

BACKGROUND: Immunization is one of the most effective ways of preventing illness, disability and death from infectious diseases for older people. However, worldwide immunization rates are still low, particularly for the most vulnerable groups within the elderly population. The objective of this study was to estimate the effect of the Oportunidades -an incentive-based poverty alleviation program- on vaccination coverage for poor and rural older people in Mexico. METHODS: Cross-sectional study, based on 2007 Oportunidades Evaluation Survey, conducted in low-income households from 741 rural communities (localities with <2,500 inhabitants) of 13 Mexican states. Vaccination coverage was defined according to three individual vaccines: tetanus, influenza and pneumococcal, and for complete vaccination schedule. Propensity score matching and linear probability model were used in order to estimate the Oportunidades effect. RESULTS: 12,146 older people were interviewed, and 7% presented cognitive impairment. Among remaining, 4,628 were matched. Low coverage rates were observed for the vaccines analyzed. For Oportunidades and non-Oportunidades populations were 46% and 41% for influenza, 52% and 45% for pneumococcal disease, and 79% and 71% for tetanus, respectively. Oportunidades effect was significant in increasing the proportion of older people vaccinated: for complete schedule 5.5% (CI95% 2.8-8.3), for influenza 6.9% (CI95% 3.8-9.6), for pneumococcal 7.2% (CI95% 4.3-10.2), and for tetanus 6.6% (CI95% 4.1-9.2). CONCLUSIONS: The results of this study extend the evidence on the effect that conditional transfer programs exert on health indicators. In particular, Oportunidades increased vaccination rates in the population of older people. There is a need to continue raising vaccination rates, however, particularly for the most vulnerable older people.

Effect of social capital and personal autonomy on the incidence of depressive symptoms in the elderly: evidence from a longitudinal study in Mexico.

OBJECTIVES: To estimate the effect of social capital (SC) and personal autonomy (PA) on the depressive symptoms (DS) in older people living in poverty. METHOD: Longitudinal study of elderly participants in the impact evaluation study of a non-contributory pension program in Mexico. For this study we selected the group of older people without significant DS at baseline. PA, SC indicators and covariates were measured at baseline. Using the Geriatric Depression Scale, the incidence of DS was assessed at a follow-up interview after 11 months. The effect of SC and autonomy on the occurrence of DS was estimated by using a multilevel logistic regression model. RESULTS: Of the various indicators of PA, not being dependent in daily functioning, and being able to read/write were associated with lower risk of DS. A higher level of SC at baseline was associated with lower incidence of DS in women (odds ratio; OR = 0.73, p < 0.01), while for men there was no significant association (OR = 1.04, p = 0.69). CONCLUSIONS: PA and SC proved to be protective factors against the onset of DS in women. For men, only PA was a protective factor. Future studies need to explore in what ways that PA and SC may reduce risk of DS as well as the role of gender differences.