Cancer Screening in Low- and Middle-Income Countries.

The worldwide cancer burden is growing, and populations residing in low- and middle-income countries (LMICs) are experiencing a disproportionate extent of this growth. Breast, colorectal, and cervical cancers are among the top 10 most frequently diagnosed malignancies, and they also account for a substantial degree of cancer mortality internationally. Effective screening strategies are available for all three of these cancers. Individuals from LMICs face substantial cost and access barriers to early detection programs, and late stage at diagnosis continues to be a major cause for cancer mortality in these communities. This chapter will review the epidemiology of breast, colorectal, and cervical cancers, and will explore prospects for improving global control through novel approaches to screening in cost-constrained environments.

Impact of Fee For Service on the Efficiency and Survival of Seguro Popular's Patients With Acute Lymphoblastic Leukemia in Mexico.

PURPOSE: Cost containment and efficiency in the provision of health care are primary concerns for health systems that aim to provide affordable, high-quality care. Between 2005 and 2015, Seguro Poplar's Fund against Catastrophic Expenditures (FPGC) funded ALL treatment in Mexico. Before January 1, 2011, FPGC reimbursed a fixed amount per patient according to risk. In 2011, the per capita reimbursement method changed to fee for service. We used this natural experiment to estimate the impact of the reimbursement policy change on average expenditure and quality of care for ALL treatment in Mexico. METHODS: We used nationwide reimbursement data from the Seguro Poplar's FPGC from 2005 to 2015. We created a patient cohort to assess 3-year survival and estimate the average reimbursement before and after the fee-for-service policy. We examined survival and expenditure impacts, controlling for patients' and providers' characteristics, including sex, risk (standard and high), the volume of patients served, type of institution (federally funded v other), and level of care. To quantify the impact, we used a regression discontinuity approach. RESULTS: The average reimbursement for standard-risk patients in the 3-year survival cohort was $16,512 US dollars (USD; 95% CI, 16,042 to 17,032) before 2011 and $10,205 USD (95% CI, 4,659 to 12,541) under the fee-for-service reimbursement scheme after 2011. The average annual reimbursement per patient decreased by 136% among high-risk patients. The reduction was also significant for the standard-risk cohort, although the magnitude was substantially smaller (34%). CONCLUSION: As Mexico's government is currently restructuring the health system, our study provides evidence of the efficiency and effectiveness of the funding mechanism in the Mexican context. It also serves as a proof of concept for using administrative data to evaluate economic performance and quality of care of publicly funded health programs.

The Cervical Cancer Treatment Gap in Mexico Under Seguro Popular, 2006-2016.

From 2005 to 2019, the Mexican government financed cervical cancer treatment for individuals without social security insurance through Seguro Popular's Fund for Protection against Catastrophic Health Expenses. To better understand the impact of this program on access to treatment, we estimated the cervical cancer treatment gap (the proportion of patients with cervical cancer in this population who did not receive treatment). To calculate the expected number of incident cervical cancer cases we used national surveys with information on insurance affiliation and incidence estimates from the Global Burden of Disease study. We used a national claims database to determine the number of cases whose treatment was financed by Seguro Popular. From 2006 to 2016, the national cervical cancer treatment gap changed from 0.61 (95% CI 0.59 to 0.62) to 0.45 (95% CI 0.43 to 0.48), with an average yearly reduction of -0.012 (95% CI -0.024 to -0.001). The gap was greater in states with higher levels of marginalization and in the youngest and oldest age groups. Although the cervical cancer treatment gap among individuals eligible for Seguro Popular decreased after the introduction of public financing for treatment, it remained high. Seguro Popular was eliminated in 2019; however, individuals without social security have continued to receive cancer care financed by the government in the same healthcare facilities. These results suggest that barriers to care persisted after the introduction of public financing for treatment. These barriers must be reduced to improve cervical cancer care in Mexico, particularly in states with high levels of marginalization.

Breast cancer survival in Mexico between 2007 and 2016 in women without social security: a retrospective cohort study.

Background: Essential indicators of health system performance for breast cancer are lacking in Mexico. We estimated survival and clinical stage distribution for women without social insurance who were treated under a health financing scheme that covered 60% of the Mexican population. Methods: We conducted a retrospective cohort study cross-linking reimbursement claims for 56,847 women treated for breast cancer between 2007 and 2016 to a mortality registry. We estimated overall- and clinical stage-specific survival and breast cancer survival according to patient age, state of residence, marginalization, type of treatment facility, and patient volume of the treatment facility. We also explored the distribution of clinical stage according to age, year of treatment initiation, and state where the woman was treated. We used log-rank tests and estimated 95% CIs to compare differences between patient groups. Findings: Median age was 52 years (interquartile range [IQR] 45, 61) (Sixty five percent patients (36,731/56,847) had advanced disease at treatment initiation. Five-year overall survival was 72.2% (95% CI 71.7, 72.6). For early disease (excluding stage 0), 5-year overall survival was 89.0% (95% CI 88.4, 89.5), for locally advanced disease 69.9% (95% CI 69.0, 70.2) and for metastatic 36.9% (95% CI 35.4, 38.4). Clinical stage at treatment initiation and breast cancer survival remained unchanged in the period analyzed. Clinical stage and survival differed across age groups, state of residence, and type of facility where women received treatment. Interpretation: In the absence of population-based cancer registries, medical claims data may be efficiently leveraged to estimate essential cancer-related performance indicators. Funding: The authors received no financial support for this research.

Health Risk Assessment in Children Occupationally and Para-Occupationally Exposed to Benzene Using a Reverse-Translation PBPK Model.

Benzene is a known human carcinogen and one of the ten chemicals of major public health concern identified by the World Health Organization. Our objective was to evaluate benzene's carcinogenic and non-carcinogenic health risks (current and projected) in highly exposed children in Yucatan, Mexico. Benzene exposure was estimated through a reverse-translation, four-compartment, physiologically based pharmacokinetic model (PBPK) based on previously performed urine trans, trans-muconic acid (benzene metabolite) determinations. Using a risk assessment methodology, the carcinogenic and non-carcinogenic risks of benzene were estimated for 6-12-year-old children from a family of shoemakers. The children's hazard quotients for decreased lymphocyte count were 27 and 53 for 4 and 8 h/day exposure, respectively, and 37 for the projected 8 h/day exposure in adults. The risks of developing leukemia were 2-6 cases in 1000 children exposed 4 h/day; 4-10 cases in 1000 children exposed 8 h/day, and 2-9 cases in 1000 adults with an 8 h/day lifetime exposure. Children in Yucatan working in shoe-manufacturing workshops, or living next to them, are exposed to benzene concentrations above the reference concentration and have unacceptably high risks of presenting with non-carcinogenic and carcinogenic hematologic symptoms, now and in the future. Interventions to prevent further exposure and mitigate health risks are necessary.

Reduction in the Treatment Gap for Breast Cancer in Mexico under Seguro Popular, 2007 to 2016.

As Mexico's government restructures the health system, a comprehensive assessment of Seguro Popular's Fund for Protection against Catastrophic Expenses (FPGC) can help inform decision makers to improve breast cancer outcomes and health system performance. This study aimed to estimate the treatment gap for breast cancer patients treated under FPGC and assess changes in this gap between 2007 (when coverage started for breast cancer treatment) and 2016. We used a nationwide administrative claims database for patients whose breast cancer treatment was financed by FPGC in this period (56,847 women), Global Burden of Disease breast cancer incidence estimates, and other databases to estimate the population not covered by social security. We compared the observed number of patients who received treatment under FPGC to the expected number of breast cancer cases among women not covered by social security to estimate the treatment gap. Nationwide, the treatment gap was reduced by more than half: from 0.71, 95% CI (0.69, 0.73) in 2007 to 0.15, 95%CI (0.09, 0.22) in 2016. Reductions were observed across all states . This is the first study to assess the treatment gap for breast cancer patients covered under Seguro Popular. Expanded financing through FPGC sharply increased access to treatment for breast cancer. This was an important step toward improving breast cancer care, but high mortality remains a problem in Mexico. Increased access to treatment needs to be coupled with effective interventions to assure earlier cancer diagnosis and earlier initiation of high-quality treatment.

Serious financial difficulties, psychological stress, and subclinical cardiovascular disease in Mexican women.

PURPOSE: To investigate the association between serious financial difficulties (SFD), stress, and cardiovascular health in women. METHODS: We categorized 1759 employed and insured disease-free women from the Mexican Teachers' Cohort according to their response to a question on SFD included in the Life Stressor Checklist-Revised administered in 2012 and 2016. We also measured perceived stress (n = 1598) and hair cortisol levels (n = 539) in study participants. Carotid intima-media thickness was measured, and carotid atherosclerosis determined in all participants. RESULTS: Multivariable regression models indicated that women exposed to SFD had 1.6% (95% CI: 0.05, 3.2) higher mean intima-media thickness and 1.37 (95% CI: 1.02, 1.85) higher odds of carotid atherosclerosis relative to women without SFD. The magnitude of the observed associations was higher in women reporting longer duration of the event and higher emotional burden. Mediation analyses suggested a potential role of perceived stress and body mass index in these associations. Cortisol levels did not differ between groups. CONCLUSIONS: SFD was associated with subclinical cardiovascular disease among employed and insured women. Limiting stress and adiposity may be potential targets for interventions.

Acute Lymphoblastic Leukaemia Survival in Children Covered by Seguro Popular in Mexico: A National Comprehensive Analysis 2005-2017.

The aim of the study was to measure survival of children with acute lymphoblastic leukemia (ALL) under Mexico's public health insurance for the population treated under Seguro Popular. A retrospective cohort study using claims data from Mexico's Seguro Popular program, covering cancer treatment from 2005 to 2015 was conducted. Overall 5-year national and state-specific survival for children with ALL across Mexico who initiated cancer treatment under this program was estimated. From 2005 to 2015, 8,977 children with ALL initiated treatment under Seguro Popular. Under this financing scheme, the annual number of treated children doubled from 535 in 2005 to 1,070 in 2015. The estimates for 5-year overall survival of 61.8% (95%CI 60.8, 62.9) remained constant over time. We observed wide gaps in risk-standardized 5-year overall survival among states ranging from 74.7% to 43.7%. We found a higher risk of mortality for children who received treatment in a non-pediatric specialty hospital (Hazards Ratio, HR = 1.18; 95%CI 1.09, 1.26), facilities without a pediatric oncology/hematology specialist (HR = 2.17; 95%CI 1.62, 2.90), and hospitals with low patient volume (HR = 1.22; 95%CI 1.13, 1.32). In a decade Mexico's Seguro Popular doubled access to ALL treatment for covered children and by 2015 financed the vast majority of estimated ALL cases for that population. While some progress in ALL survival may have been achieved, nationwide 5-year overall survival did not improve over time and did not achieve levels found in comparable countries. Our results provide lessons for Mexico's evolving health system and for countries moving toward universal health coverage.

National and state-level colorectal cancer mortality trends in Mexico, 1998-2018.

OBJECTIVE: To describe the burden of colorectal cancer (CRC) in Mexico and understand mortality patterns based on sex, geography, and insurance status. MATERIALS AND METHODS: Mortality data (1998-2018) from the Instituto Nacional de Estadística y Geografía was obtained. We included colon (C18.0, C18.2-18.9) and rectal cancer ICD-10 codes (C19, C20), and estimated age-standardized national, state-level and health insurance mortality rates. We estimated the average annual percent change using joinpoint regression. RESULTS: Between 1998 and 2018, the observed women and men mortality rate increased annually by 1.3 and 2.7%, respectively. Higher CRC mortality was observed in northern and more urbanized states and in groups with greater access to health insurance, which currently facilitates but does not routinely cover screening. CONCLUSION: CRC mortality in Mexico is increasing rapidly, with marked differences based on sex, geography, and insurance status. Our findings underscore potential benefits of increased investment in comprehensive screening, diagnosis, and treatment strategies for the general population.

The Politics of Taxes for Health: An Analysis of the Passage of the Sugar-Sweetened Beverage Tax in Mexico.

This article explores the politics of passage of the sugar-sweetened beverage (SSB) tax in Mexico, using published documents, media articles, and interviews with key stakeholders. The article examines first the period of agenda setting when the tax was included in the President's fiscal reform package; and second, the period of legislative passage, when the bill was introduced in Congress and was passed. The analysis uses Kingdon's three streams theory of agenda setting, to explain how the tax emerged on the agenda and how agenda setting shaped and enabled legislative passage. The article offers five lessons related to the politics of passing the SSB tax in Mexico. First, passing an SSB tax was difficult and required high-level organization, cooperation, planning, and effort. Second, supporters needed an understanding of how to manage the political and economic context, facilitated by a grant from Bloomberg Philanthropies. Third, framing the tax as generating revenue helped get the proposal onto the policy agenda and enabled buy-in from the powerful Ministry of Finance (Hacienda). Fourth, forming networks within the legislature early on allowed tax proponents to have a network of allies within Congress ready when the SSB tax was introduced as a bill. Finally, early public relations campaigns helped shape public perception that Mexico's obesity epidemic was driven in part by SSB consumption. This is the first paper that uses political science theory and primary data collection and interviews with a broad range of stakeholders, to explain how Mexico passed an SSB tax despite opposition from a strong national SSB industry.

Prostate cancer screening in low- and middle- income countries: the Mexican case / Tamizaje para cáncer de próstata en países de bajos y medianos ingresos: el caso mexicano

Abstract: Prostate-specific antigen (PSA)-based early detection for prostate cancer is the subject of intense debate. Implementation of organized prostate cancer screening has been challenging, in part because the PSA test is so amenable to opportunistic screening. To the extent that access to cancer screening tests increases in low- and middle-income countries (LMICs), there is an urgent need to thoughtfully evaluate existing and future cancer screening strategies to ensure benefit and control costs. We used Mexico's prostate cancer screening efforts to illustrate the challenges LMICs face. We provide five considerations for policymakers for a smarter approach and implementation of PSA-based screening.

Resumen : El uso del Antígeno Prostático Específico (APE) para tamizaje para cáncer de próstata sigue siendo tema de amplio debate. La implementación de estrategias de tamiz organizado de cáncer de próstata ha sido un reto en parte porque la prueba de APE se presta para detección oportunista. A medida que aumenta el acceso a las pruebas de detección de cáncer en los países de ingresos bajos y medianos (PIBM), existe la necesidad urgente de evaluar cuidadosamente las estrategias actuales y futuras de detección oportuna de cáncer para garantizar su beneficio y controlar sus costos. Utilizamos los esfuerzos de tamizaje de cáncer de próstata de México para ilustrar los retos para PIBM. Ofrecemos cinco consideracio nes dirigidas a tomadores de decisión que permitan contar con estrategias racionales de implementación de tamizaje para cáncer de próstata basado en el uso de APE.

Prostate cancer screening in low- and middle-income countries: the Mexican case.

Prostate-specific antigen (PSA)-based early detection for prostate cancer is the subject of intense debate. Implementation of organized prostate cancer screening has been challenging, in part because the PSA test is so amenable to opportunistic screening. To the extent that access to cancer screening tests increases in low- and middle-income countries (LMICs), there is an urgent need to thoughtfully evaluate existing and future cancer screening strategies to ensure benefit and control costs. We used Mexico's prostate cancer screening efforts to illustrate the challenges LMICs face. We provide five considerations for policymakers for a smarter approach and implementation of PSA-based screening.

El uso del Antígeno Prostático Específico (APE) para tamizaje para cáncer de próstata sigue siendo tema de amplio debate. La implementación de estrategias de tamiz organizado de cáncer de próstata ha sido un reto en parte porque la prueba de APE se presta para detección oportunista. A medida que aumenta el acceso a las pruebas de detección de cáncer en los países de ingresos bajos y medianos (PIBM), existe la necesidad urgente de evaluar cuidadosamente las estrategias actuales y futuras de detección oportuna de cáncer para garantizar su beneficio y controlar sus costos. Utilizamos los esfuerzos de tamizaje de cáncer de próstata de México para ilustrar los retos para PIBM. Ofrecemos cinco consideraciones dirigidas a tomadores de decisión que permitan contar con estrategias racionales de implementación de tamizaje para cáncer de próstata basado en el uso de APE.

Soda Intake Is Directly Associated with Serum C-Reactive Protein Concentration in Mexican Women.

Background: Soda intake is associated with an increased risk of cardiovascular disease. Consumption of diet sodas, often considered healthy alternatives to sodas, could also increase the likelihood of cardiovascular outcomes. Objective: This study aims to evaluate the relation between soda and diet soda and biomarkers of cardiovascular risk. Methods: We conducted a cross-sectional analysis among 825 Mexican women free of diabetes, cardiovascular disease, and cancer, and for whom serum concentrations of C-reactive protein (CRP), C-peptide, adiponectin, and leptin were available. Mean ± SD age was 45.9 ± 6.6 y, the majority of women were premenopausal (60.4%), and the prevalence of obesity was 35%. We estimated the adjusted percentage differences in biomarkers and 95% CIs by performing multiple linear regression models comparing categories of consumption for soda and diet soda adjusting for age, family history of heart disease, menopause, menopausal hormone therapy, socioeconomic status, region, smoking, physical activity, alcohol intake, and dietary patterns. Results: In the entire study sample we observed a 50% higher serum CRP concentration in women in the highest soda intake quartile (median intake: 202.9 mL/d, IQR: 101.4, 304.3 mL/d) compared to those in the lowest (median intake: 11.8 mL/d, IQR: 0.0, 152.1 mL/d). After stratification by menopausal status, results remained significant only for premenopausal women. Premenopausal women in the highest quartile of soda intake had 56% higher CRP concentration relative to women in the lowest quartile. We observed no significant association with the other biomarkers. After further adjustment for body mass index, a potential mediator, results remained significant only for CRP. Diet soda consumption was not associated with any of the biomarkers. Conclusions: Consumption of soda was associated with adverse levels in a biomarker of inflammation and cardiovascular risk, serum CRP, in Mexican women. These results add to the accumulating evidence on soda and cardiovascular risk. More research is necessary to understand the potential impact of artificially sweetened sodas.

Dietary acid load and risk of type 2 diabetes: the E3N-EPIC cohort study.

AIMS/HYPOTHESIS: The objective of this study was to evaluate the prospective relationship between dietary acid load, assessed with both the potential renal acid load (PRAL) and the net endogenous acid production (NEAP) scores, and type 2 diabetes risk. METHODS: A total of 66,485 women from the E3N-EPIC cohort were followed for incident diabetes over 14 years. PRAL and NEAP scores were derived from nutrient intakes. HRs for type 2 diabetes risk across quartiles of the baseline PRAL and NEAP scores were estimated with multivariate Cox regression models. RESULTS: During follow-up, 1,372 cases of incident type 2 diabetes were validated. In the overall population, the highest PRAL quartile, reflecting a greater acid-forming potential, was associated with a significant increase in type 2 diabetes risk, compared with the first quartile (HR 1.56, 95% CI 1.29, 1.90). The association was stronger among women with BMI <25 kg/m2 (HR 1.96, 95% CI 1.43, 2.69) than in overweight women (HR 1.28, 95% CI 1.00, 1.64); statistically significant trends in risk across quartiles were observed in both groups (p trend < 0.0001 and p trend = 0.03, respectively). The NEAP score provided similar findings. CONCLUSIONS/INTERPRETATION: We have demonstrated for the first time in a large prospective study that dietary acid load was positively associated with type 2 diabetes risk, independently of other known risk factors for diabetes. Our results need to be validated in other populations, and may lead to promotion of diets with a low acid load for the prevention of diabetes. Further research is required on the underlying mechanisms.

Changes in fish consumption in midlife and the risk of coronary heart disease in men and women.

Without data from randomized trials, the long-term effects of fish consumption on coronary heart disease (CHD) need to be inferred from observational studies. We estimated CHD risk under different hypothetical interventions on fish consumption during mid- and later life in 2 prospective US cohorts of 25,797 men in the Health Professionals Follow-Up Study and 53,772 women in the Nurses' Health Study. Participants provided information on risk factors and disease every 2 years and on diet every 4 years. We adjusted for baseline and time-varying risk factors for CHD by using the parametric g-formula (where g stands for "generalized"). We observed 1,865 incident CHD cases among men (in 1990-2008) and 1,891 CHD cases among women (in 1986-2008). The risk ratios for CHD when comparing the risk if everyone had consumed at least 2 servings of fish per week with the risk if no one consumed fish during the follow-up periods were 1.03 (95% confidence interval: 0.90, 1.15) for men and 0.87 (95% confidence interval: 0.76, 0.98) for women. Our results suggest that increasing fish consumption to at least 2 servings per week in mid- or later life may lower CHD risk in women but not in men. Our analytical approach allowed us to explicitly specify hypothetical interventions and to assess the effectiveness of dietary changes in midlife.