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.

Chromosomal evolution, environmental heterogeneity, and migration drive spatial patterns of species richness in Calochortus (Liliaceae).

We used nuclear genomic data and statistical models to evaluate the ecological and evolutionary processes shaping spatial variation in species richness in Calochortus (Liliaceae, 74 spp.). Calochortus occupies diverse habitats in the western United States and Mexico and has a center of diversity in the California Floristic Province, marked by multiple orogenies, winter rainfall, and highly divergent climates and substrates (including serpentine). We used sequences of 294 low-copy nuclear loci to produce a time-calibrated phylogeny, estimate historical biogeography, and test hypotheses regarding drivers of present-day spatial patterns in species number. Speciation and species coexistence require reproductive isolation and ecological divergence, so we examined the roles of chromosome number, environmental heterogeneity, and migration in shaping local species richness. Six major clades-inhabiting different geographic/climatic areas, and often marked by different base chromosome numbers (n = 6 to 10)-began diverging from each other ~10.3 Mya. As predicted, local species number increased significantly with local heterogeneity in chromosome number, elevation, soil characteristics, and serpentine presence. Species richness is greatest in the Transverse/Peninsular Ranges where clades with different chromosome numbers overlap, topographic complexity provides diverse conditions over short distances, and several physiographic provinces meet allowing immigration by several clades. Recently diverged sister-species pairs generally have peri-patric distributions, and maximum geographic overlap between species increases over the first million years since divergence, suggesting that chromosomal evolution, genetic divergence leading to gametic isolation or hybrid inviability/sterility, and/or ecological divergence over small spatial scales may permit species co-occurrence.

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.

Floral Diversity and Pollination Syndromes in Agave subgenus Manfreda.

The genus Agave is an ecological keystone of American deserts and both culturally and economically important in Mexico. Agave is a large genus of about 250 species. The radiation of Agave is marked by an initial adaptation to desert environments and then a secondary diversification of species associated with pollinator groups, such as hummingbirds and nocturnal moths. Phylogenetic analyses place Agave subgenus Manfreda, or the "herbaceous agaves," in a monophyletic clade that likely evolved in part as an adaptation to novel pollination vectors. Here, we present a morphological and observational study assessing the evolution of floral form in response to pollinator specialization within this understudied group. We found significant visitation by hummingbirds and nocturnal moths to several species within the Agave subgenus Manfreda. These observations also align with our morphological analyses of floral organs and support the evolution of distinct pollination syndromes. We found that not all floral morphology is consistent within a pollination syndrome, suggesting hidden diversity in the evolution of floral phenotypes in Agave. We also characterize the morphological variation between herbarium and live specimens, demonstrating that special consideration needs to be made when combining these types of data. This work identifies the potential for studying the functional evolution of diverse floral forms within Agave and demonstrates the need to further explore ecological and evolutionary relationships to understand pollinator influence on diversification in the genus.

Apendicitis aguda dentro de una hernia de Spiegel: un caso infrecuente de una patología infrecuente.

INTRODUCTION: Spigelian hernia is a rare entity, with higher improbability of acute appendicitis within it. CASE REPORT: A 75-year-old female with a 30-year evolution hernia, abdominal pain, and fever of 1 week of onset, in whom was found an acute appendicitis within a Spigelian hernia. DISCUSSION: Spigelian hernia comprises 0.12-2% of all abdominal hernias. Presurgical diagnosis is stablished only in 50% of cases, with an hernial ring less than 2 cm and hidden localization. There isn't statistics of this complication because of the lack of case reports.

INTRODUCCIÓN: La hernia de Spiegel es una afección infrecuente, con una improbabilidad aún mayor de apendicitis aguda en su interior. CASO CLÍNICO: Mujer de 75 años que acude con una hernia de 30 años, dolor abdominal y fiebre de 1 semana de inicio, en quien se encontró apendicitis aguda dentro de una hernia de Spiegel. DISCUSIÓN: La hernia de Spiegel comprende el 0.12-2% de las hernias abdominales. El diagnóstico prequirúrgico se ha logra en el 50% de los casos, con defecto menor de 2 cm y de localización oculta. No existe estadística de esta complicación debido a la escasez de casos reportados.

Geographic isolation and long-distance gene flow influence the genetic structure of the blue fan palm Brahea armata (Arecaceae).

The formation of the Baja California Peninsula (BCP) has impacted the microevolutionary dynamics of different species in ways that depend on biological traits such as dispersal capacity. Plants with relatively low levels of vagility have exhibited high genetic divergence between the BCP and Continental mainland. Brahea armata (Arecaceae) is a palm species inhabiting the northern part of the BCP and Sonora; its distribution occurs in isolated oases of vegetation. We aimed to evaluate the influence of the formation of the BCP on the genetic structure of B. armata using nuclear microsatellites and chloroplast markers (cpDNA) to compare patterns of genetic diversity and structure with previous published studies. Because gene flow through seeds is usually more limited compared to pollen flow, we expect to find stronger genetic structure at (cpDNA) than at nuclear markers. Moreover, larger genetic structure might also be explained by the smaller effective population size of cpDNA. We analyzed six microsatellite markers and two cpDNA regions. The main results indicated high levels of genetic differentiation among isolated populations located in the BCP, while low genetic differentiation was found between southern populations of the BCP and Sonora, suggesting long distance gene flow. In contrast, chloroplast markers indicated high levels of genetic structure between BCP and Sonora populations, suggesting asymmetrical gene flow between pollen (measured by nuclear microsatellites) and seed (cpDNA markers). This study provides valuable information on genetic diversity of B. armata that can be relevant for conservation and management; and develops microsatellites markers that can be transferred to other Brahea species.

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.

Incorporating evolutionary and threat processes into crop wild relatives conservation.

Crop wild relatives (CWR) intra- and interspecific diversity is essential for crop breeding and food security. However, intraspecific genetic diversity, which is central given the idiosyncratic threats to species in landscapes, is usually not considered in planning frameworks. Here, we introduce an approach to develop proxies of genetic differentiation to identify conservation areas, applying systematic conservation planning tools that produce hierarchical prioritizations of the landscape. It accounts for: (i) evolutionary processes, including historical and environmental drivers of genetic diversity, and (ii) threat processes, considering taxa-specific tolerance to human-modified habitats, and their extinction risk status. Our analyses can be used as inputs for developing national action plans for the conservation and use of CWR. Our results also inform public policy to mitigate threat processes to CWR (like crops living modified organisms or agriculture subsidies), and could advise future research (e.g. for potential germplasm collecting). Although we focus on Mesoamerican CWR within Mexico, our methodology offers opportunities to effectively guide conservation and monitoring strategies to safeguard the evolutionary resilience of any taxa, including in regions of complex evolutionary histories and mosaic landscapes.

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.

Development and Evaluation of a Body-Worn Dosimeter for Continuous and Impulsive Noise.

Noise exposure is encountered nearly everyday in both recreational and occupational settings, and can lead to a number of health concerns including hearing-loss, tinnitus, social-isolation and possibly dementia. Although guidelines exist to protect workers from noise, it remains a challenge to accurately quantify the noise exposure experienced by an individual due to the complexity and non-stationarity of noise sources. This is especially true for impulsive noise sources, such as weapons fire and industrial impact noise which are difficult to quantify due to technical challenges relating to sensor design and size, weight and power requirements. Because of this, personal noise dosimeters are often limited to a maximum 140 dB SPL and are not sufficient to measure impulse noise. This work details the design of a body-worn noise dosimeter (mNOISE) that processes both impulse and continuous noise ranging in level from 40 dBA-185 dBP (i.e. a quiet whisper to a shoulder fired rocket). Also detailed is the capability of the device to log the kurtosis of the sound pressure waveform in real-time, which is thought to be useful in characterizing complex noise exposures. Finally, we demonstrate the use of mNOISE in a military-flight noise environment. Clinical Relevance- On-body noise exposure monitoring can be used by audiologists industrial hygiene personnel and others to determine threshold of injury adequate hearing protection requirements and ultimately reduce permanent noise-induced hearing loss.

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.

Alternative cue and response modalities maintain the Simon effect but impact task performance.

Inhibitory control, the ability to inhibit impulsive responses and irrelevant stimuli, enables high level functioning and activities of daily living. The Simon task probes inhibition using interfering stimuli, i.e., cues spatially presented on the opposite side of the indicated response; incongruent response times (RT) are slower than congruent RTs. Operational applicability of the Simon task beyond finger/hand manipulations and visual/auditory cues is unclear, but important to consider as new technologies provide tactile cues and require motor responses from the lower extremity (e.g., exoskeletons). In this study, twenty participants completed the Simon task under four conditions, each combination of two cue (visual/tactile) and response (upper/lower-extremity) modalities. RT were significantly longer for incongruent than congruent cues across cue-response pairs. However, alternative cue-response pairs yielded slower RT and decreased accuracy for tactile cues and lower-extremity responses. Results support operational usage of the Simon task to probe inhibition using tactile cues and lower-extremity responses relevant for new technologies like exoskeletons and immersive environments.

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.