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.

Long-term inequalities in health among older Mexican adults: An outcome-wide analysis.

The relationship between socioeconomic level and health outcomes in older people has been widely studied, but less information about health inequalities associated with gender and place of residence exists. Also, there is scarce evidence of longitudinal inequalities, particularly in countries from the global south. This study aimed to describe the longitudinal patterns of health inequalities associated with wealth, gender, and residence area among older Mexican adults. We used data from two longitudinal studies in Mexico: The Study on Global AGEing and Adult Health (SAGE) and the Mexican Health and Aging Study (MHAS). Three domains to characterize health inequities were used: wealth, gender, and rurality. We conducted an outcome-wide analysis with nine health indicators assessing older adults' physical and cognitive function. The Slope Index of Inequality and the Relative Index of Inequality were used as inequality measurements. Our results indicate that the greatest inequalities are observed in relation to wealth and gender. Older adults with lower socioeconomic status demonstrated higher rates of depression, sarcopenia, falls, and limitations in both basic and instrumental activities of daily living compared to their wealthier counterparts, with increasing trends in physical functionality over time. Furthermore, women experienced higher rates of depression, sarcopenia, frailty, and physical limitations compared to men. The only significant difference related to rurality was a lower rate of frailty among rural older adults. Longitudinal trajectories revealed an increase in the gap of inequality for various health indicators, especially in terms of wealth and gender. Health inequalities in old age are one of the greatest challenges facing health systems globally. Actions like universal coverage of health services for older people and the empowerment of individuals and their communities to have control over their lives and circumstances must be guaranteed.

Telomere Length is Associated with the Prevalence, Persistence, and Incidence of Sarcopenia.

BACKGROUND: Telomere length (TL) shortening has been identified as a marker of aging and associated with adverse health outcomes, but evidence of its association with sarcopenia is inconclusive. AIMS: Estimate the cross-sectional and prospective associations between TL and sarcopenia. METHODS: We used data from Waves 3 and 4 (2017, 2021) of the Study on Global Aging and Adult Health in Mexico (SAGE-Mexico). The cross-sectional sample consisted of 1,738 adults aged 50 and older, and the longitudinal sample consisted of 1,437. Relative TL was determined by real-time quantitative polymerase chain reaction (qPCR) on DNA extracted from saliva samples and quantified as the telomere/single-copy gene (T/S) ratio. Sarcopenia was defined according to the European Working Group on Sarcopenia in Older People (EWGSOP2). RESULTS: The mean salivary TL was 1.50 T/S units (95% CI: 1.49-1.52). The baseline prevalence of sarcopenia was 13.3% (95% CI: 9.8-16.8%). The incidence and persistence of sarcopenia were 6.8% (95% CI: 5.0-9.5%) and 7.0% (95% CI: 5.1-9.6%), respectively. The results showed that a one standard deviation decrease in TL was cross-sectionally associated with higher odds of sarcopenia (OR = 1.31; 95% CI: 1.03-1.67) and prospectively with a higher incidence (RRR = 1.55; 95% CI: 1.06-2.25) and persistence (RRR = 1.50; 95% CI: 1.01-2.24) of sarcopenia. CONCLUSIONS: Older adults with shorter TL had higher rates of incident and persistent sarcopenia. Implementation of interventions to delay the decline of TL in older adults is warranted. Further translational studies are needed to elucidate the effects of exercise or diet on DNA repair in the telomeric region and their associations with sarcopenia.

Prospective changes in anemia are associated with the incidence and persistence of sarcopenia among older Mexican adults.

Background: Low hemoglobin levels are a significant biomarker in the prognosis of sarcopenia. Anemia and sarcopenia are frequent and disabling conditions in the older adult population, but little is known about the role of anemia in the onset and progression of sarcopenia. This study aimed to determine whether prospective changes in anemia are associated with the incidence and persistence of sarcopenia. Methods: Data come from the second and third waves (2014, 2017) of the World Health Organization (WHO) Study on global AGEing and adult health (SAGE) in Mexico. SAGE-Mexico is a dynamic cohort with national representativeness, including a follow-up sample and new enrollments. For this study, 1,500 older adults (aged 50 or above) with measurements in both waves were included. Sarcopenia was defined as having low muscle quantity and either/both slow gait speed and weak handgrip strength. Anemia was defined according to hemoglobin concentrations, adjusted for altitude, as recommended by the WHO, <120 g/L for women and <130 g/L for men. Multinomial logistic regression was used to estimate the association between anemia and prospective changes in sarcopenia. Results: The baseline prevalence of anemia was 17.4%, and that of sarcopenia was 12.1%. The incidence and persistence of anemia were 10.6% (95% CI: 7.3-15.0%) and 6.9% (95% CI: 4.7-9.8%), respectively, and for sarcopenia, they were 5.3% (95% CI: 3.7-7.7%) and 9.2% (95% CI: 6.4-13.0%), respectively. Incident anemia was associated with incident (RRR = 3.64, 95% CI: 1.18-11.19) but not with persistent (RRR = 0.75, 95% CI: 0.18-3.20) sarcopenia. Persistent anemia was significantly associated with persistent (RRR = 3.59, 95% CI: 1.14-11.27) but not incident (RRR = 1.17, 95% CI: 0.30-4.54) sarcopenia. Conclusion: Changes in anemia are significantly associated with incident and persistent sarcopenia. Primary actions to promote a healthy diet rich in antioxidants, high-quality proteins, and micronutrients, as well as moderate physical activity and maintaining a healthy weight, are crucial for the aging population to delay the deleterious effects of anemia and sarcopenia.

Intrinsic capacity trajectories and socioeconomic inequalities in health: the contributions of wealth, education, gender, and ethnicity.

BACKGROUND: Life-long health inequalities exert enduring impacts and are governed by social determinants crucial for achieving healthy aging. A fundamental aspect of healthy aging, intrinsic capacity, is the primary focus of this study. Our objective is to evaluate the social inequalities connected with the trajectories of intrinsic capacity, shedding light on the impacts of socioeconomic position, gender, and ethnicity. METHODS: Our dynamic cohort study was rooted in three waves (2009, 2014, 2017) of the World Health Organization's Study on Global AGEing and Adult Health in Mexico. We incorporated a nationally representative sample comprising 2722 older Mexican adults aged 50 years and over. Baseline measurements of socioeconomic position, gender, and ethnicity acted as the exposure variables. We evaluated intrinsic capacity across five domains: cognition, psychological, sensory, vitality, and locomotion. The Relative Index of Inequality and Slope Index of Inequality were used to quantify socioeconomic disparities. RESULTS: We discerned three distinct intrinsic capacity trajectories: steep decline, moderate decline, and slight increase. Significant disparities based on wealth, educational level, gender, and ethnicity were observed. Older adults with higher wealth and education typically exhibited a trajectory of moderate decrease or slight increase in intrinsic capacity. In stark contrast, women and indigenous individuals were more likely to experience a steeply declining trajectory. CONCLUSIONS: These findings underscore the pressing need to address social determinants, minimize gender and ethnic discrimination to ensure equal access to resources and opportunities across the lifespan. It is imperative for policies and interventions to prioritize these social determinants in order to promote healthy aging and alleviate health disparities. This approach will ensure that specific demographic groups receive customized support to sustain their intrinsic capacity during their elder years.

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.

Trajectories of sleep duration and quality and their association with mild cognitive impairment, frailty, and all-cause mortality.

OBJECTIVES: To identify longitudinal trajectories of sleep duration and quality and estimate their association with mild cognitive impairment, frailty, and all-cause mortality. METHODS: We used data from three waves (2009, 2014, 2017) of the WHO Study on Global Aging and Adult Health in Mexico. The sample consisted of 2722 adults aged 50 and over. Sleep duration and quality were assessed by self-report. Sleep trajectories were determined by applying growth mixture models. Mixed-effects logistic (mild cognitive impairment) and ordinal logistic (frailty), and Cox proportional hazards (all-cause mortality) models were fitted. RESULTS: Three classes for sleep duration ("optimal-stable," "long-increasing," and "short-decreasing") and quality ("very good-increasing," "very good-decreasing," and "moderate/poor stable") were identified. Compared to the optimal-stable group, the long-increasing trajectory had greater odds for mild cognitive impairment (odds ratio=1.68, 95% CI: 1.01-2.78) and frailty (odds ratio=1.66, 95% CI: 1.13-2.46), and higher risk for all-cause mortality (hazard ratio=1.91, 95% CI: 1.14-3.19); and the short-decreasing class had a higher probability of frailty (odds ratio=1.83, 95% CI: 1.26-2.64). Regarding the sleep quality, the moderate/poor stable trajectory had higher odds of frailty (odds ratio=1.71, 95% CI: 1.18-2.47) than very good-increasing group. CONCLUSIONS: These results have important implications for clinical practice and public health policies, given that the evaluation and treatment of sleep disorders need more attention in primary care settings. Interventions to detect and treat sleep disorders should be integrated into clinical practice to prevent or delay the appearance of alterations in older adults' physical and cognitive function. Further research on sleep quality and duration is warranted to understand their contribution to healthy aging.

Depression, Anxiety, and Stress Scale: Factor validation during the first COVID-19 lockdown in Mexico

Introduction: Globally, mental health problems have affected nearly 1 billion people and approximately 1 in 10 Mexicans. The detection and surveillance of depression, anxiety, and stress in Mexico requires more reliable and valid instruments. Objective: To determine the factor validity and internal consistency of the Depression, Anxiety, and Stress Scale-21 items (DASS-21) in a non-probabilistic national sample of Mexican adults. Method: Cross-sectional study by means of an online survey of 1 613 Mexican adults aged 18 years and older. The Spanish version of the DASS-21 was used, which evaluates the presence of depressive symptoms, anxiety, and stress. Factor validity was determined by comparing different confirmatory factor analysis models: one-dimensional, three factors (correlated and non-correlated), second order, and bifactor. Results: The application of the bifactor model to the DASS 21, supports its validity for identifying the presence of symptoms of depression, anxiety, and stress, as well as an altered general emotional state in a sample of Mexican adults. Conclusions: The DASS-21 is a theoretically robust instrument useful for research and clinical practice.

Introducción: A nivel global los problemas de salud mental han alcanzado a cerca de 1 billón de personas y aproximadamente a uno de cada diez mexicanos. La detección y vigilancia de depresión, ansiedad y estrés en México demandan instrumentos más confiables y válidos. Objetivo: Determinar la validez factorial y consistencia interna de la Escala de Depresión, Ansiedad y Estrés (DASS-21) en una muestra nacional no probabilística de adultos mexicanos. Método: Estudio transversal por medio de una encuesta en línea entre 1 613 adultos me-xicanos de 18 años o más. Se utilizó la versión en español del DASS-21 que evalúa la presencia de síntomas depresivos, ansiedad y estrés. La validez factorial se determinó mediante la comparación de distintos modelos del análisis factorial confirmatorio: unidimensional; tres factores (correlacionados y no), de segundo orden, y bifactor. Resultados: La aplicación del modelo bifactor al DASS-21 sustenta su validez para identificar la presencia de síntomas de depresión, ansiedad y estrés, así como de un estado general emocional alterado en una muestra de adultos mexicanos. Conclusiones: El DASS-21 es un instrumento teóricamente robusto útil para la investigación y la práctica clínica.

Development and Validation of a Cutoff for the Chair Stand Test as a Screening for Mobility Impairment in the Context of the Integrated Care for Older People Program.

BACKGROUND: The 5-repetition chair stand test (CST) is increasingly being used to assess locomotion capacity in older adults. However, there is a lack of age-stratified cutoffs for adults aged ≥70 validated against a higher risk of functional loss. METHODS: We used 2 population-based studies (Study on global AGEing and adult health in Mexico [SAGE Mexico] and Toledo Study for Healthy Aging [TSHA]) and receiver operating characteristic (ROC) analyses to develop and cross-validate age-stratified chair stand cutoffs with activities of daily living (ADL) disability as the outcome. Then, we used data from an randomized controlled trial (RCT) (Multidomain Alzheimer Preventive Trial [MAPT]) and a frailty day-hospital for external validation with cross-sectional and longitudinal measures of ADL disability. The merged sample of SAGE Mexico and TSHA was n = 1 595; sample sizes for external validation were: MAPT n = 1 573 and Frailty day-hospital n = 2 434. The Cox models for incident disability in MAPT had a mean follow-up of 58.6 months. RESULTS: Cutoffs obtained were 14 second (ages 70-79) and 16 second (ages 80+). Those cutoffs identified older adults at higher odds of incident ADL disability odds ratio (OR) = 1.72 (95% confidence interval [CI] 1.06; 2.78) for ages 70-79 and odds ratio (OR) = 2.27 (95% CI 1.07; 4.80) in those aged 80+. Being a slow chair stander according to the cut points was associated with ADL disability in cross-sectional and longitudinal measures. CONCLUSIONS: Fourteen- and 16-second cut points for the CST are suitable to identify people at higher risk of functional decline among older adults in Mexico and Toledo, Spain. Adjusting the cut point from 14 to 16 second generally improved the psychometric properties of the test. The validation of these cutoffs can facilitate the screening for limited mobility and the implementation of the Integrated Care for Older People program.

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.

Clinically meaningful change for the chair stand test: monitoring mobility in integrated care for older people.

BACKGROUND: Clinically meaningful changes in the five-repetition chair stand test are essential for monitoring mobility in integrated care for older people. Recommendations for the clinically meaningful change of the chair stand test are not well known. Our study aimed to estimate the absolute and relative clinically meaningful changes for older adults' five-repetition chair stand test. METHODS: We applied distribution-based and anchor-based methods in addition to receiver operator characteristics analyses to a population-based study of community-dwelling adults (SAGE Mexico study, n = 897) to derive the clinically meaningful change in the chair stand test. We used three self-reported clinical anchors: moving around, vigorous activities, and walking 1 km. Our primary outcome was the incidence of disability for basic activities of daily living (ADL). Secondly, we examined our estimates of clinically meaningful change in a clinical trial population of healthy volunteers (MAPT, France, study n = 1575) concerning the risk of incident ADL disability. RESULTS: The age of SAGE Mexico participants ranged from 60 to 96 years; mean (SD) = 69.0 (6.2); 54.4% were female. Their baseline chair stand time averaged 12.1 s (SD = 3 s). Forty-eight participants (5.6%) showed incident disability over 3 years. The absolute and relative clinically meaningful change cut points found over 3 years of follow-up were 2.6 s and 27.7%, respectively. Absolute clinically meaningful change ranged from 0.5 to 4.7 s, depending on the estimation method. Relative clinically meaningful change ranged from 9.6 to 46.2%. SAGE Mexico participants with absolute and relative clinically meaningful declines (increasing 2.6 s and 27.7% from baseline time, respectively) showed an increased risk of ADL disability [aRR = 1.93; P = 0.0381; 95% CI (1.05, 3.46) and aRR = 2.27; P = 0.0157; 95% CI (1.22, 4.10)], respectively, compared with those without a clinically meaningful decline. MAPT participants [age range = 70-94; mean (SD) = 75.3 (4.4); 64.8% female; incident ADL disability over 5 years = 145(14.8%)] with a relative clinically meaningful decline (≥27.7% from baseline over 3 years) had a 74% higher risk of incident ADL disability than their counterparts [aHR = 1.74; P = 0.016; CI95% (1.11, 2.72); mean follow-up of 58 months]. CONCLUSIONS: Community-dwelling older adults with an increase of 3 s or 28% in chair stand test performance over 3 years (approximately 1 s or 10% per year) could be the target of interventions to enhance mobility and prevent incident disability.

Longitudinal trajectories of intrinsic capacity and their association with quality of life and disability.

OBJECTIVES: Intrinsic capacity (IC) is a key concept within the World Health Organization's (WHO) healthy aging model. The systematic assessment of IC could provide a better understanding of the functional trajectories of individuals. Our aims were to identify the longitudinal trajectories of IC and estimate their association with quality of life and disability. STUDY DESIGN: The study data comes from the three waves of the WHO Study on global AGEing and adult health (SAGE) in Mexico (2009, 2014, 2017). In total, 2735 adults aged 50 years or more were included. An IC score was constructed using item response theory. We used growth mixture modeling (GMM) to investigate the longitudinal trajectories of IC. Three-level linear mixed effect models were used to estimate the associations of IC with quality of life and disability. MAIN OUTCOME MEASURES: Disability was measured using the WHO Disability Assessment Schedule (WHODAS 2.0) and quality of life using the WHOQOL (WHO Quality of Life) instrument. RESULTS: Three classes were identified: low baseline IC with a steeply decreasing trajectory, medium baseline IC with a slightly decreasing trajectory, and high baseline IC with a moderately increasing trajectory. The class with the better trajectory (higher baseline IC score and a moderately increasing pattern) exhibited higher quality-of-life scores and lower disability scores. CONCLUSIONS: The findings show that older Mexican adults exhibit different IC trajectories, and that these may be associated with quality of life and disability. Results highlight the need for health policies and strategies to maintain intrinsic capacity and to promote primary prevention.

Is there an association between inflammatory markers and lower physical performance in older adults?

BACKGROUND: Maintenance of physical performance is essential for achievement of healthy aging. A few studies have explored the association between inflammatory markers and physical performance in older adults with inconclusive results. Our aim was to analyze the association of tumor necrosis factor-alpha (TNF-α), Interleukin-10 (IL-10), and C-reactive protein (CRP) with physical performance in a sample of older adults in rural settings of Mexico. METHODS: Our study comprised 307 community-dwelling older men and women who participated in the third wave of the Rural Frailty Study. We assessed the physical performance with the Short Physical Performance Battery (SPPB) and classified older adults as low performance if SPPB scored ≤8. Inflammatory markers were ascertained using serum by immunodetection methods. Logistic regression models were used to estimate the associations between inflammatory markers and physical performance. RESULTS: In comparison with the normal physical performance group, low physical performance individuals mainly were female (P <  0.01), older (P <  0.01), more illiterate (P = 0.02), more hypertensive (P < 0.01), fewer smokers (P = 0.02), and had higher CRP levels (P < 0.01). The logistic model results showed a significant association between the 3rd tertile of CRP and low physical performance (OR = 2.23; P = 0.03). IL-10 and TNF-α levels did not show a significant association. CONCLUSIONS: The results of this study were mixed, with a significant association of physical performance with higher CRP levels but nonsignificant with IL-10 and TNF-α. Further studies with improved designs are needed by incorporating a broader set of inflammatory markers.

Physical activity and sedentary behavior trajectories and their associations with quality of life, disability, and all-cause mortality.

BACKGROUND: Physical activity (PA) and sedentary behavior (SB) are not stable conditions but change over time and among individuals, and both could have deleterious effects on health-related outcomes among older adults. This study aimed to identify the longitudinal trajectories of PA and SB and estimate their association with quality of life, disability, and all-cause mortality in a national sample of older Mexican adults. METHODS: Data comes from three waves of the WHO Study on global AGEing and adult health (SAGE) in Mexico (2009, 2014, 2017). In total, 3209 older adults ages 50 and above were included. PA and SB were determined by using the Global Physical Activity Questionnaire (GPAQ). Disability was measured using the WHO Disability Assessment Schedule (WHODAS 2.0), quality of life using the WHOQOL (WHO Quality of Life) instrument, and all-cause mortality using a verbal autopsy. We used growth mixture modeling (GMM) to investigate the longitudinal trajectories of PA and SB. Three-level linear mixed effect models were used to estimate the associations of PA and SB with quality of life and disability and the Cox model for the association with all-cause mortality. RESULTS: Three longitudinal trajectories of PA and SB were found: low-PA-decreasers, moderate-PA-decreasers, and high-PA-decreasers for PA; and low-maintainers, steep-decreasers, and steep-increasers for SB. Decreased quality of life, increased disability, and all-cause mortality were all consistently associated with worse PA and SB trajectories. CONCLUSIONS: Our results highlight the need for health policies and prevention strategies that promote PA and limit SB in middle-aged adults. Further studies should consider these activities/behaviors as exposures that vary throughout life and work to identify vulnerable groups of older adults for whom physical activation interventions and programs would be most impactful.

Changes Among Mexican Adults in Physical Activity and Screen Time During the COVID-19 Lockdown Period and Association With Symptoms of Depression, Anxiety, and Stress, May 29-July 31, 2020.

INTRODUCTION: We examined the association between changes in physical activity and leisure screen time and mental health outcomes during the early stages of the recommended COVID-19 stay-at-home period in a national sample of Mexican adults aged 18 years or older. METHODS: A cross-sectional online survey conducted from May 29 through July 31, 2020, among 1,148 participants, reported time spent in physical activity and leisure screen time during a typical week before (retrospectively) and a week during the COVID-19 stay-at-home period. Mental health outcomes during this period were measured with the Depression, Anxiety and Stress Scale (DASS-21). Linear regression models were used to estimate the associations between changes in physical activity and leisure screen time and mental health outcomes by socioeconomic status (SES), adjusting for potential confounders. RESULTS: Compared with maintaining high levels of physical activity or increasing them, decreasing physical activity was associated with higher stress scores overall, and among people of high SES, with higher scores for DASS-21, depression, and anxiety. Among participants of low and medium SES only, increasing screen time was associated with higher DASS-21, depression, anxiety, and stress scores compared with maintaining low or decreasing leisure screen time. CONCLUSION: Results highlight the potential protective effect of physical activity and limited leisure screen time on mental health in the context of COVID-19 stay-at-home restrictions.

Preferences for Conditional Economic Incentives to Improve Pre-exposure Prophylaxis Adherence: A Discrete Choice Experiment Among Male Sex Workers in Mexico.

Pre-exposure prophylaxis (PrEP) is highly effective in preventing HIV but requires sustained adherence. Conditional economic incentives (CEIs) can improve medication-taking behaviors, yet preferences for programs that employ CEIs to increase PrEP use among male sex workers (MSWs) have not been investigated. We conducted a discrete choice experiment in Mexico City to elicit stated preferences for a CEI-based PrEP adherence program among MSWs. Respondents expressed their preferences for different program characteristics: incentive amount; incentive format; incentive type; and adherence-verification method. We used a random utility logit model to estimate the relative importance of each attribute and estimated willingness-to-pay. MSWs preferred a higher, fixed incentive, with PrEP adherence measured via hair sampling. MSWs were willing to forego up to 21% of their potential maximum CEI amount to ensure receipt of a fixed payment. MSWs are highly willing to accept a CEI-based intervention for PrEP adherence, if offered along with fixed payments.

RESUMEN: La profilaxis previa a la exposición (PrEP) es muy eficaz para prevenir el VIH, pero requiere una adherencia sostenida. Los incentivos económicos condicionales (IEC) pueden mejorar los comportamientos de toma de medicamentos, sin embargo, no se han investigado las preferencias por los programas que emplean IEC para aumentar el uso de PrEP entre los trabajadores sexuales masculinos (TSM). Realizamos un experimento de elección discreta con TSM en la Ciudad de México para obtener preferencias declaradas para un programa de adherencia a la PrEP basado en IEC. Los participantes expresaron sus preferencias en cuanto a diferentes características: monto del incentivo; formato del incentivo; tipo de incentivo; y método de verificación de la adherencia. Utilizamos un modelo logit de utilidad aleatoria para estimar la importancia relativa de cada atributo y la disposición a pagar estimada (DAP). Los TSM prefirieron un incentivo fijo más alto, con la adherencia a la PrEP medida a través de muestras de cabello. Los TSM estaban dispuestos a renunciar hasta el 21% de su monto máximo potencial de IEC para garantizar la recepción de un pago fijo. Los TSM están muy dispuestos a aceptar una intervención basada en IEC para la adherencia a la PrEP, si se ofrece junto con pagos fijos.

Etiology of Anemia in Older Mexican Adults: The Role of Hepcidin, Vitamin A and Vitamin D.

Anemia in older adults is a growing public health issue in Mexico; however, its etiology remains largely unknown. Vitamin A deficiency (VAD) and vitamin D deficiency (VDD) have been implicated in the development of anemia, though by different mechanisms. The aim of this study is to analyze the etiology of anemia and anemia-related factors in older Mexican adults. This is a cross-sectional study of 803 older adults from the southern region of Mexico in 2015. The anemia etiologies analyzed were chronic kidney disease (CKD), nutritional deficiencies (ND), anemia of inflammation (AI), anemia of multiple causes (AMC) and unexplained anemia (UEA). VAD was considered to be s-retinol ≤ 20 µg/dL, and VDD if 25(OH)D < 50 nmol/L. IL-6 and hepcidin were also measured. Multinomial regression models were generated and adjusted for confounders. Anemia was present in 35.7% of OA, independent of sex. UEA, CKD, AI and ND were confirmed in 45%, 29.3%, 14.6% and 7% of older adults with anemia, respectively. Hepcidin and log IL-6 were associated with AI (p < 0.05) and CKD (p < 0.001). VAD was associated with AI (p < 0.001), and VDD with ND and AMC (p < 0.05). Log-IL6 was associated with UEA (p < 0.001). In conclusion, anemia in older adults has an inflammatory component. VAD was associated to AI and VDD with ND and AMC.

Longitudinal association of sarcopenia and mild cognitive impairment among older Mexican adults.

BACKGROUND: Recent evidence from cross-sectional and longitudinal studies supports the hypothesis that sarcopenia is associated with worsening cognitive function. However, primary evidence largely comes from high-income countries, whereas in low- and middle-income countries, this association has been underexplored. This study aimed to estimate the longitudinal association between sarcopenia and mild cognitive impairment in a sample of older Mexican adults. METHODS: Data come from the three waves of the World Health Organization (WHO) Study on Global AGEing and Adult Health (SAGE) in Mexico (2009, 2014, 2017). Four hundred ninety-six older adults, aged ≥50, were included. Sarcopenia was defined as having low muscle quantity and either/both slow gait speed and weak handgrip strength. Mild cognitive impairment was determined based on the recommendations of the National Institute on Aging-Alzheimer's Association. Cognitive function was evaluated by a composite cognitive score of five different cognitive tests: immediate and delayed recall, forward and backward digit span and semantic verbal fluency. Three-level mixed-effects models (logistic and linear) were used to estimate the longitudinal associations between sarcopenia, mild cognitive impairment and cognitive function. RESULTS: The prevalence of mild cognitive impairment (8.9%, 12.9%, 16.0%) and sarcopenia (10.5%, 20.7%, 23.3%) showed a significant temporal increase for Waves 1, 2 and 3 (P-value < 0.01, respectively). The presence of sarcopenia was significantly associated with mild cognitive impairment (OR = 1.74; CI95% 1.02, 2.96; P = 0.04) and worse cognitive function (ß = -0.57; CI95% -0.93, -0.21; P < 0.01). We observed significant associations between sarcopenia and immediate verbal recall (ß = -0.14; CI95% -0.28, -0.01; P = 0.04), delayed verbal recall (ß = -0.12; CI95% -0.23, -0.01; P = 0.03) and semantic verbal fluency (ß = -0.17; CI95% -0.28, -0.05; P = 0.01). The prevalence of mild cognitive impairment increased at an annual rate of 0.8% for non-sarcopenic older adults, but nearly 1.5% for sarcopenic adults. CONCLUSIONS: Significant longitudinal associations were observed between sarcopenia, mild cognitive impairment and cognitive function among older Mexican adults. Public health strategies, including policy research and clinical interventions, must be implemented in low- and middle-income countries in order to reduce or delay the onset of sarcopenia and thus improve population-level cognitive health among older adults.

Sleep duration and incident frailty: The Rural Frailty Study.

BACKGROUND: The association between sleep duration and frailty remains unconclusive since most of the studies have been cross-sectional. Therefore, this study aimed to analyze the association between sleep duration, sleep complaints, and incident frailty. METHODS: A community-based cohort study from rural areas in Mexico with 309 older adults aged 70 and over. Data from waves two and three of the Rural Frailty Study were used. We operationalized the Fried frailty phenotype to describe prevalent and incident frailty at two consecutive waves. Sleep duration was classified as: ≤ 5 h, 6 h, 7-8 h, and ≥ 9 h; and the self-reported sleep complaints as a dichotomous variable. Analyses were performed using Poison regression models. RESULTS: The average age was 76.2 years and 55.3% were women; the incidence of frailty was 30.4%; 13.3% slept ≤5 h, and 38.5% ≥ 9 h. Compared with the group that slept 7-8 h, the risk of frailty at 4.4 years of follow-up was significantly higher among those who slept ≤5 h (adjusted RR 1.80, 95% CI: 1.04-3.11) and among those who slept ≥9 h (adjusted RR 1.69, 95% CI: 1.10-2.58). Sleep complaints were not associated with incident frailty (adjusted RR 1.41, 95% CI: 0.94-2.12). CONCLUSIONS: Our results show that short and long sleep duration are associated with the incidence of frailty. Studies that objectively evaluate sleep duration are needed to clarify whether meeting the recommended hours of sleep decreases frailty incidence.

Severity Levels of Disability Among Older Adults in Low- and Middle-Income Countries: Results From the Study on Global Ageing and Adult Health (SAGE).

Background: Recent studies suggest the importance of distinguishing the severity levels of disability in the older adult population. However, there is still no consensus regarding an optimal classification. Few studies have estimated the prevalence of severe disability, and the results have been confined to high-income countries. There is no evidence for low- and middle-income countries (LMICs). Therefore, the aim of this study was to provide estimates of the levels of severity associated with disability in older adult populations in LMICs and to examine their relationship with health and socioeconomic factors. Methods: We used data from the Study on global AGEing and adult health (SAGE), wave 1 (2007-2010). Nationally representative samples of adults over 50 years from China, Ghana, India, Mexico, Russian Federation, and South Africa were analyzed (n = 33,641). We measured disability using the World Health Organization Disability Assessment Instrument version 2.0 (WHODAS 2.0). Disability levels according to severity were identified through the use of latent class analysis. Socioeconomic and health factors associated with severe disability were estimated using ordinal logistic regression models. Results: We identified four groups of older adult: (1) without disability, 43.4%; (2) mild disability, 33.3%; (3) moderate disability, 15.3%; and (4) severe disability, 8.0%. These results were heterogeneous for the six countries analyzed. Education and socioeconomic status were significantly associated with severe disability along with the following chronic conditions: angina, arthritis, asthma, cataracts, chronic obstructive pulmonary disease, depression, diabetes, and stroke. Severe disability was also associated with the frailty status, sarcopenia, and mild cognitive impairment. Conclusions: In this study, we estimated severity levels of disability for the older adult population in LMICs. Our results show that severe disability affects 8% of older adult, and that there are important socioeconomic and health factors associated with this condition. Measuring the severity of disability is a critical element to study the causes and consequences of aging. Moreover, the identification of older adult with severe disability is vital to design prevention programs, modify interventions, or develop enabling environments.