Loss of Cognitive Function in Mexican children due to lead exposure and the associated economic costs.

BACKGROUND: Lead exposure reduces the cognitive development and future economic prospects of children. While previous studies in high-income settings have explored productivity losses associated with lead exposure, limited research has focused on low and middle-income countries like Mexico. OBJECTIVES: This study aims to provide a comprehensive assessment of the economic implications of lead exposure on Mexican children using, for the first time, nationally representative Blood lead levels (BLLs) measurements in children aged 1-4, specifically focusing on the costs of forgone lifetime income due to cognitive losses. METHODS: BLLs of children aged 1-4 were extracted from the 2018-2019 National Health and Nutrition Survey (ENSANUT). Estimations of cognitive losses were derived from a log-linear relationship between BLLs and IQ loss. Lost lifetime economic productivity per child was calculated, assuming a 2% reduction in lifetime potential productivity for each IQ point lost due to lead exposure, based on previous literature (Attina and Trasande, 2013; Larsen and Sanchez-Triana, 2023). Productivity data were obtained from representative sources for Mexico. RESULTS: The estimated economic loss amounted to US $33.02 billion, equivalent to 2.76% of Mexico's Gross Domestic Product (GDP) in 2019 (calculated for a 1-year cohort). On a national scale, the long-term loss of cognition for children 1-4 years old is 4.14 IQ points per child due to lead exposure, with significant variability across States (range: 3.26 to 5.26). Lead-poisoned children (≥5 µg/dL) suffered an average loss of 6.42 IQ points (range: 0 to 6.97). In terms of economic impact, some States like Chiapas experienced losses of 7.08% of its GDP, while others had losses as low as 0.67%. Intriguingly, states with lower Human Development Indexes (HDIs) exhibited relatively higher economic losses despite lower average blood lead levels. DISCUSSION: The heterogeneous impact of lead exposure across Mexican states underscores the necessity for tailored regional policies. These findings emphasize the urgency for targeted interventions and informed policy measures to mitigate the socioeconomic consequences of lead exposure on Mexican children.

A surge in food insecurity during the COVID-19 pandemic in a cohort in Mexico City.

BACKGROUND: The COVID-19 pandemic has not only caused tremendous loss of life and health but has also greatly disrupted the world economy. The impact of this disruption has been especially harsh in urban settings of developing countries. We estimated the impact of the pandemic on the occurrence of food insecurity in a cohort of women living in Mexico City, and the socioeconomic characteristics associated with food insecurity severity. METHODS: We analyzed data longitudinally from 685 women in the Mexico City-based ELEMENT cohort. Food insecurity at the household level was gathered using the Latin American and Caribbean Food Security Scale and measured in-person during 2015 to 2019 before the pandemic and by telephone during 2020-2021, in the midst of the pandemic. Fluctuations in the average of food insecurity as a function of calendar time were modeled using kernel-weighted local polynomial regression. Fixed and random-effects ordinal logistic regression models of food insecurity were fitted, with timing of data collection (pre-pandemic vs. during pandemic) as the main predictor. RESULTS: Food insecurity (at any level) increased from 41.6% during the pre-pandemic period to 53.8% in the pandemic stage. This increase was higher in the combined severe-moderate food insecurity levels: from 1.6% pre-pandemic to 16.8% during the pandemic. The odds of severe food insecurity were 3.4 times higher during the pandemic relative to pre-pandemic levels (p<0.01). Socioeconomic status quintile (Q) was significantly related to food insecurity (Q2 OR = 0.35 p<0.1, Q3 OR = 0.48 p = 0.014, Q4 OR = 0.24 p<0.01, and Q5 OR = 0.17 p<0.01), as well as lack of access to social security (OR = 1.69, p = 0.01), and schooling (OR = 0.37, p<0.01). CONCLUSIONS: Food insecurity increased in Mexico City households in the ELEMENT cohort as a result of the COVID-19 pandemic. These results contribute to the body of evidence suggesting that governments should implement well-designed, focalized programs in the context of economic crisis such as the one caused by COVID-19 to prevent families from the expected adverse health and well-being consequences associated to food insecurity, especially for the most vulnerable.

Contribución de diversas fuentes de exposición a la concentración de plomo en sangre en población infantil mexicana, Ensanut 2022.

OBJETIVO: Analizar la asociación entre fuentes de exposición al plomo (FEPb) y la concentración en sangre capilar (PbS) en menores de 1 a 4 años de edad a nivel nacional y regional, así como cuantificar la contribución relativa de las distintas FEPb. Material y métodos. Se utilizaron datos de la Encuesta Nacional de Salud y Nutrición (Ensanut 2022). Las FEPb consideradas fueron uso de loza de barro vidriada con plomo (LBVPb), residencia cercana a sitios contaminados y exposición paraocupacional. Se estimaron prevalencias de intoxicación (PbS ≥ 5.0 mg/dL) y medias geométricas de PbS. Se utilizaron modelos de regresión para PbS (escala logarítmica) y la descomposición Shapley-Owen de R2 para evaluar la contribución relativa de cada FEPb. RESULTADOS: Las FEPb estudiadas explican el 6% de la variabilidad de PbS a nivel nacional; de este, el 87.3% lo explica el uso de LBVPb, el 4.2% otras FEPb ambiental y 1.3% FEPb paraocupacionales. La contribución relativa del uso de LBVPb varía entre regiones, desde 38.1 a 76.8%. Algunas regiones destacan la FEPb ambiental, pero no paraocupacional. CONCLUSIONES: Los resultados confirman que el uso de LBVPb es la principal fuente de exposición reportada y sugieren que la población no identifica las principales FEPb documentadas hasta ahora.

Intoxicación infantil por plomo en México: otras fuentes de exposición más allá del barro vidriado (Ensanut 2022).

OBJETIVO: Describir y actualizar al año 2022 la prevalencia de intoxicación por plomo (Pb) en la población infantil de 1-4 años en México y describir fuentes de exposición ambiental, paraocupacional y uso de barro vidriado (BV). Material y métodos. Estudio en una muestra de menores que participaron en la Encuesta Nacional de Salud y Nutrición 2022 (Ensanut 2022). Se midió la concentración de plomo en sangre (PbS) capilar. Se aplicó un cuestionario para indagar sobre fuentes de exposición a Pb. RESULTADOS: Se midió PbS en 1 158 menores de 1-4 años. La prevalencia nacional de intoxicación por Pb (≥5.0 µg/dL) fue 16.8% (IC95%:13.6,20.5). La proporción de hogares que reportó exposición a una fuente exclusiva fue de 21.2, 17.7 y 7.4% para BV, exposición ambiental y paraocupacional, respectivamente. La prevalencia de intoxicación de los expuestos a una sola fuente fue 21.5%, y esta cifra aumenta a 24.2% entre quienes reportaron exposición combinada tres tipos de fuentes. Conclusión. La prevalencia nacional de intoxicación por plomo permaneció estable con respecto a lo reportado en la Ensanut 2018-19. El uso de BV es una fuente de exposición relevante, pero no es la única. Se identificó una contribución importante por exposición ambiental y, en menor medida, de exposición paraocupacional.

The Cost of Providing Comprehensive HIV Services to Key Populations: An Analysis of the LINKAGES Program in Kenya and Malawi.

INTRODUCTION: Timely data on HIV service costs are critical for estimating resource needs and allocating funding, but few data exist on the cost of HIV services for key populations (KPs) at higher risk of HIV infection in low- and middle-income countries. We aimed to estimate the total and per contact annual cost of providing comprehensive HIV services to KPs to inform planning and budgeting decisions. METHODS: We collected cost data from the Linkages across the Continuum of HIV Services for Key Populations Affected by HIV (LINKAGES) program in Kenya and Malawi serving female and male sex workers, men who have sex with men, and transgender women. Data were collected prospectively for fiscal year (FY) 2019 and retrospectively for start-up activities conducted in FY2015 and FY2016. Data to estimate economic costs from the provider's perspective were collected from LINKAGES headquarters, country offices, implementing partners (IPs), and drop-in centers (DICs). We used top-down and bottom-up cost estimation approaches. RESULTS: Total economic costs for FY2019 were US$6,175,960 in Kenya and US$4,261,207 in Malawi. The proportion of costs incurred in IPs and DICs was 66% in Kenya and 42% in Malawi. The costliest program areas were clinical services, management, peer outreach, and monitoring and data use. Mean cost per contact was US$127 in Kenya and US$279 in Malawi, with a mean cost per contact in DICs and IPs of US$63 in Kenya and US$104 in Malawi. CONCLUSION: Actions undertaken above the service level in headquarters and country offices along with those conducted below the service level in communities, comprised important proportions of KP HIV service costs. The costs of pre-service population mapping and size estimation activities were not negligible. Costing studies that focus on the service level alone are likely to underestimate the costs of delivering HIV services to KPs.

Estimating the cost of HIV services for key populations provided by the LINKAGES program in Kenya and Malawi.

BACKGROUND: Data remain scarce on the costs of HIV services for key populations (KPs). The objective of this study was to bridge this gap in the literature by estimating the unit costs of HIV services delivered to KPs in the LINKAGES program in Kenya and Malawi. We estimated the mean total unit costs of seven clinical services: post-exposure prophylaxis (PEP), pre-exposure prophylaxis (PrEP), HIV testing services (HTS), antiretroviral therapy (ART), sexually transmitted infection (STI) services, sexual and reproductive health (SRH) services, and management of sexual violence (MSV). These costs take into account the costs of non-clinical services delivered alongside clinical services and the pre-service and above-service program management integral to the LINKAGES program. METHODS: Data were collected at all implementation levels of the LINKAGES program including 30 drop-in-centers (DICs) in Kenya and 15 in Malawi. This study was conducted from the provider's perspective. We estimated economic costs for FY 2019 and cost estimates include start-up costs. Start-up and capital costs were annualized using a discount rate of 3%. We used a combination of top-down and bottom-up costing approaches. Top-down methods were used to estimate the costs of headquarters, country offices, and implementing partners. Bottom-up micro-costing methods were used to measure the quantities and prices of inputs used to produce services in DICs. Volume-weighted mean unit costs were calculated for each clinical service. Costs are presented in 2019 United States dollars (US$). RESULTS: The mean total unit costs per service ranged from US$18 (95% CI: 16, 21) for STI services to US$635 (95% CI: 484, 785) for PrEP in Kenya and from US$41 (95% CI: 37, 44) for STI services to US$1,240 (95% CI 1156, 1324) for MSV in Malawi. Clinical costs accounted for between 21 and 59% of total mean unit costs in Kenya, and between 25 and 38% in Malawi. Indirect costs-including start-up activities, the costs of KP interventions implemented alongside clinical services, and program management and data monitoring-made up the remaining costs incurred. CONCLUSIONS: A better understanding of the cost of HIV services is highly relevant for budgeting and planning purposes and for optimizing HIV services. When considering all service delivery costs of a comprehensive HIV service package for KPs, costs of services can be significantly higher than when considering direct clinical service costs alone. These estimates can inform investment cases, strategic plans and other budgeting exercises.

Ab Initio Calculations of Chitosan Effects on the Electronic Properties of Unpassivated Triangular ZnO Nanowires Oriented along [0001] Directions.

In recent years, both chitosan and ZnO nanostructures have been identified as potential antibacterial substances; however, the potential applications of chitosan adsorbed on ZnO nanowires have not been explored and could offer exciting new perspectives for both materials, for example, in biocompatible electronic circuits. In this work, we investigate the effect of chitosan on the electronic properties of triangular ZnO nanowires (ZnO NWs) from a theoretical perspective. All calculations were performed using density functional theory within the generalized gradient approximation. We considered six different positions of the chitosan molecule (CS) on the nanowire surface. We varied the amine position of CS, viewing it parallel, perpendicular, and at a 45° angle with respect to the NW axis. Our results show that all configurations are chemically stable; moreover, the interaction of the NW surface with the OH radical of CS creates flat states within the band gap energy of the ZnO NWs that might resemble p-doping. In addition, these states induce changes in the band gap energy of the ZnO NWs. All NWs show high chemical stability regardless of the CS position; hence, the adsorption results of all NW assemblies appear to be chemically favorable.

Association between density of stores and purchases of ultra-processed food and sugar-sweetened beverages in Mexico.

In Mexico, purchases of ultra-processed food and sugar-sweetened beverages (SSB) and the number of large supermarkets, discount and convenience stores are growing. The objective of this study was to analyze the association between the density of different types of food stores and ultra-processed food and SSB (taxed beverages) purchases in a representative sample of Mexican households. Results show that the density of convenience stores (national and in urban areas) was significantly associated with higher purchases of ultra-processed food and that supermarkets were marginally associated. Our findings are stronger for beverages where we found that convenience stores, discount stores, small grocery stores and stores speciliazed in selling candies, popsicles, soft drinks and other food were associated with higher purchases of taxed beverages. Mexico should implement or strengthen current policies to reduce purchases of ultra-processed food and sugar-sweetened beverages and to regulate the location and density of stores.

Psoriatic arthritis in patients with psoriasis: A clinical-epidemiological study at a dermatology center in western Mexico.

BACKGROUND/OBJECTIVE: Psoriatic arthritis (PsA) is a chronic inflammatory illness. Approximately, 15% of psoriasis patients have undiagnosed PsA. In Mexico, we found no related studies. Our objective was to investigate the clinical-epidemiological characteristics of PsA in psoriasis patients in western Mexico. METHODS: A cross-sectional study including Mexican patients with clinical and histopathological diagnosis of psoriasis. Physical examination, rheumatoid factor analysis and radiographies of axial and peripheral skeleton were performed. The prevalence of PsA using the CASPAR criteria, age, sex; clinical variants of PsA, psoriasis type and the Psoriasis Area and Severity Index (PASI), were assessed. Descriptive and inferential statistics were used. RESULTS: Of 90 patients with psoriasis, 48 met the criteria for PsA, with a prevalence of 53%, and average age of 50 ± 15 years. Predominating were, the female sex in 29 (60%), the axial variant of PsA in 24 (50%), and psoriasis plaques in 40 (83%). The average PASI was 12 ± 11. All cases were rheumatoid factor negative. These variables were not significantly different when comparing subjects with and without PsA, except for the female sex (60% vs. 7%; P < 0.001). CONCLUSIONS: Patients with psoriasis should intentionally be evaluated jointly Dermatologists and Rheumatologists searching joint involvement given the high prevalence of PsA previously undiagnosed.

Update of the Mexican College of Rheumatology Guidelines for the Pharmacological Treatment of Rheumatoid Arthritis, 2018. / Actualización de las guías del tratamiento farmacológico de la artritis reumatoide del Colegio Mexicano de Reumatología 2018.

Therapeutic advances in rheumatoid arthritis require periodic review of treatment guidelines. OBJECTIVE: To update the Mexican College of Rheumatology guidelines on the pharmacological treatment of rheumatoid arthritis. METHOD: Board certified rheumatologists from different health institutions and regions of the country participated. Work teams were formed that reviewed the previous guidelines, elaborated new questions, reviewed the literature, and scored the evidence that was presented and discussed in plenary session. The conclusions were presented to infectologists, gynaecologists and patients. Recommendations were based on levels of evidence according to GRADE methodology. RESULTS: Updated recommendations on the use of available medications for rheumatoid arthritis treatment in Mexico up to 2017 are presented. The importance of adequate and sustained control of the disease is emphasized and relevant safety aspects are described. Bioethical conflicts are included, and government action is invited to strengthen correct treatment of the disease. CONCLUSIONS: The updated recommendations of the Mexican College of Rheumatology on the pharmacological treatment of rheumatoid arthritis incorporate the best available information to be used in the Mexican health care system.