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Fil: Critto, María Elena. MELISA Institute. Division of Epidemiology; Chile Fil: Critto, María Elena. Pontificia Universidad Católica Argentina. Facultad de Ciencias Sociales. Programa de Doctorado en Sociología; Argentina Fil: Enríquez, Yordanis. Universidad Católica Sedes Sapientiae. Facultad de Ciencias de la Salud; Perú Fil: Bravo, Miguel. MELISA Institute. Division of Epidemiology; Chile Fil: Bravo, Miguel. University of Chile. Faculty of Medicine. School of Public Health; Chile Fil: De Janon Quevedo, Lenin. Pontificia Universidad Católica Argentina; Facultad de Ciencia Médicas; Argentina Fil: Weinbergf, Ruth. Universidad de Buenos Aires. Facultad de Ciencias Médicas; Argentina Fil: Etchegaray, Adolfo. Universidad Austral. Facultad de Medicina. Hospital Universitario Austral; Argentina Fil: Koch, Elard S. MELISA Institute. Division of Epidemiology; Chile Abstract: Abstract Background Emerging pandemic viruses may have multiple deleterious effects on maternal health. This study examines the effects of a pandemic influenza virus on cause-specific maternal mortality time series, using Argentinian vital statistics. Methods We conducted a population-based natural experiment from national vital records of maternal deaths between 1980 and 2017. Joinpoint regression models were used to model time series of the maternal mortality ratio (MMR). The sensitivity of the registry to detect the effects of the pandemic H1N1 2009 influenza virus on cause-specific MMR was analysed using a panel of parallel interrupted time series (ITS). Findings Over this 38-year study, the MMR decreased by 58¢6% (69¢5 to 28¢8 deaths/100,000 live births), transitioning from direct obstetric causes (67¢0 to 21¢1/100,000 live births; 68¢4% decrease) to indirect causes (2¢6 to 7¢7/ 100,000 live births; 196¢2% increase). The regression analysis showed an average reduction of -2¢2%/year (95% CI: -2¢9 to -1¢4) with 2 join points in the total trend (1998 and 2009). Parallel ITS analyses revealed the pandemic H1N1 virus had an increasing effect on mortality from the respiratory system- and sepsis-related complications (level change 4¢7 and 1¢6/100,000 live births respectively), reversing after the outbreak. No effect was found on MMR from hypertensive disorders, haemorrhage, abortive outcomes, other direct obstetric causes, and indirect non-respiratory comorbidities. Interpretation The Argentinian maternal death registry appears sensitive to detect different effects of emerging infectious epidemics on maternal health. In a population-based natural experiment, pandemic H1N1 virus impacted maternal mortality almost exclusively from the respiratory system- and sepsis-related complications. Supplementary material associated with this article can be found, in the online version, at doi:10.1016/j.lana.2021.100116 Resumen: Antecedentes: Los virus pandémicos emergentes pueden tener múltiples efectos nocivos sobre la salud materna. Este estudio examina los efectos de un virus de influenza pandémica mediante series de tiempo ininterrumpidas de mortalidad materna por causas específicas, utilizando estadísticas vitales argentinas. Métodos: Realizamos un experimento natural con base poblacional a partir de registros vitales nacionales de muertes maternas entre 1980 y 2017. Se utilizaron modelos de regresión con punto de unión para modelar series de tiempo de la razón de mortalidad materna (RMM). La sensibilidad del registro para detectar los efectos del virus de la influenza pandémica A H1N1 2009 sobre las causas específicas de la RMM se analizó mediante un panel de series de tiempo interrumpidas (STI). Hallazgos: Durante este estudio de 38 años, la RMM disminuyó en un 58·6% (69·5 a 28·8 muertes/100.000 nacidos vivos), pasando de causas obstétricas directas (67·0 a 21·1/100.000 nacidos vivos; 68·4% de disminución) a causas indirectas (2·6 a 7·7/100.000 nacidos vivos; 196·2% de aumento). El análisis de regresión mostró una reducción promedio de -2·2%/año (IC 95%: -2·9 a -1·4) con 2 puntos de inflexión en la tendencia total (1998 y 2009). Los análisis de STI revelaron que el virus pandémico A H1N1 tuvo un efecto creciente sobre la mortalidad por complicaciones del sistema respiratorio y relacionadas con la sepsis (cambio de nivel 4·7 y 1·6/100.000 nacidos vivos, respectivamente), revirtiéndose después del brote. No se encontró ningún efecto sobre la RMM por trastornos hipertensivos, hemorragia, desenlace abortivo, otras causas obstétricas directas y comorbilidades indirectas no respiratorias. Interpretación: El registro de defunciones maternas de Argentina parece sensible para detectar diferentes efectos de las epidemias infecciosas emergentes sobre la salud materna. En el experimento natural poblacional, el virus pandémico A H1N1 afectó la mortalidad materna casi exclusivamente por complicaciones relacionadas con el sistema respiratorio y la sepsis.

The inverse relationship between early life and adult socioeconomic measures and mortality risk has been well established in developed countries, but remains practically unexplored in Latin American societies. The setting was Chile; the study included 11,600 adults living in the urban center of San Francisco de Mostazal. This was a prospective cohort study of a weighted random sample of 795 subjects followed up during 8 years.Education (elementary, high school and college), height (percentiles 50 and 75), and income (population quartiles) were assessed at baseline. Relative risks of all-cause mortality were computed in Cox regression models adjusting for age, gender, body mass index, smoking status, and joint effects of the socioeconomic measures.A graded inverse relationship with all-cause mortality was observed for education (risk: 1.0, 0.67, and 0.30, p for trend0.01) and height (risk: 1.0, 0.75, and 0.56, p for trend0.01), but not for income (p for trend = 0.94).These findings suggest a 'pauper rich' paradox in transitioning Latin American economies. Income level does not seem sufficient to improve survival in cohorts exposed to adverse early life influences reflected by education and height.

As part of the Millennium Development Goals proposed by the United Nations, research on maternal mortality estimates and the determinants that positively influence maternal health outcomes is key for adequate evidence-based public health interventions. In the case of maternal death statistics, accuracy of estimating methods strongly depends on the quality of official records and, when unavailable, on the variables used in the predictive model, e.g. total fertility rate (TFR), percentage of childbirth delivery by skilled attendants, women’s education level, and per capita income, among others. Thus, a thorough evaluation of the reliability of estimated maternal mortality statistics is warranted before drawing any causal inference. In this regard, a recent report by Ahmed et al. provided the largest global estimate of the possible effect of contraceptive use on maternal mortality reduction and concluded that the ‘use of contraception is a substantial and effective primary

Objective. To assess the blood pressure control and cardiovascular risk factors (CVRFs) in a population of hypertensive patients with access to care under a government-financed program, the Cardiovascular Health Program (CHP).Design. A cross-sectional and multicenter study.Setting. 52 primary care centers, metropolitan area of Santiago, Chile.Participants. 1,194 patients were selected by a systematic random sampling from a universe of 316,654 hypertensive patients.Key Measurements. Demographic information, blood pressure (BP) measurements, and CVRF were extracted from medical records of patients followed for a 12-month period.Results. 59.7% of patients reached target BP<140/90 mmHg. More women were captured in the sampling (2.1 : 1), achieving better BP control than men. Diabetic patients (26.4%) had worse BP control than nondiabetics. Antihypertensive medications were used in 91.5%, with multidrug therapy more frequent in patients with higher BP and more difficult control.Conclusions. The success in improving the BP control to values /90 mmHg from 45.3% to 59.7% underscores the contribution of this program in the Chilean primary care cardiovascular preventive strategies. However, fewer hypertensive men than women were captured by this program, and it is of concern the underperforming of BP control observed in diabetics.

BackgroundThe aim of this study was to assess the main factors related to maternal mortality reduction in large time series available in Chile in context of the United Nations' Millennium Development Goals (MDGs).MethodsTime series of maternal mortality ratio (MMR) from official data (National Institute of Statistics, 1957-2007) along with parallel time series of education years, income per capita, fertility rate (TFR), birth order, clean water, sanitary sewer, and delivery by skilled attendants were analysed using autoregressive models (ARIMA). Historical changes on the mortality trend including the effect of different educational and maternal health policies implemented in 1965, and legislation that prohibited abortion in 1989 were assessed utilizing segmented regression techniques.ResultsDuring the 50-year study period, the MMR decreased from 293.7 to 18.2/100,000 live births, a decrease of 93.8%. Women's education level modulated the effects of TFR, birth order, delivery by skilled attendants, clean water, and sanitary sewer access. In the fully adjusted model, for every additional year of maternal education there was a corresponding decrease in the MMR of 29.3/100,000 live births. A rapid phase of decline between 1965 and 1981 (-13.29/100,000 live births each year) and a slow phase between 1981 and 2007 (-1.59/100,000 live births each year) were identified. After abortion was prohibited, the MMR decreased from 41.3 to 12.7 per 100,000 live births (-69.2%). The slope of the MMR did not appear to be altered by the change in abortion law.ConclusionIncreasing education level appears to favourably impact the downward trend in the MMR, modulating other key factors such as access and utilization of maternal health facilities, changes in women's reproductive behaviour and improvements of the sanitary system. Consequently, different MDGs can act synergistically to improve maternal health. The reduction in the MMR is not related to the legal status of abortion.

To test the hypothesis that an inverse association exists between socio-economic position and all-cause mortality in a developing country in Latin America.Prospective cohort study carried out in Chile using data from a simple random sample of 920 apparently healthy subjects (weighted population 11,600 aged 30-89 years) followed for 8 years.Education level (0-8 years, 9-12 years andor = 13 years) and income quartiles were established at the outset of the study, along with behavioural and biological risk factors for chronic diseases: smoking, alcohol use, obesity, diabetes, hypertension, lipids and family history of death by cardiovascular disease. Relative risks of all-cause mortality were estimated using age-adjusted Cox regression models.During the follow-up period, 46 deaths were observed. Adjusting for age, gender, and behavioural and biological risk factors, the mortality risk for increasing categories of education after controlling for income was 1.0, 0.76 and 0.33 (P for trend0.01). In contrast, the relative risk for increasing levels of income after controlling for education was 1.0, 0.98, 1.33 and 1.17 (P for trend=0.07).While education level had a protective effect on mortality risk of Chilean adults, income had a slightly unfavourable effect on survival. This finding is described as suggestive of a 'pauper-rich paradox', since the higher income quantiles in this study correspond with the lower income levels in most developed countries. Nevertheless, due to the small number of deaths, additional research is required to assess the validity of these findings.

Background: The socioeconomic position (SEP) and educational level of individuals have an inverse correlation with mortality in developed societies. Aim To assess in a society undergoing a socioeconomic transition, the mortality risk associated to a low SEP (combination of education and income, scale 0-25 points, reference > 10 points) and low education (education years, reference > 8 years), adjusting for other known risk factors. Material and methods: In this prospective cohort study, a random sample of 920 subjects, living in San Francisco de Mostazal, Chile, aged more than 20years (395 males) was examined for the first time in 1997-1999 and re-examined in 2005-2006. All had information about economic household income and level of education. A Cox regression model was used to evaluate the association between mortality and socioeconomic measures. Results: The crude mortality hazard ratio (HR) was 3.34 (95% confidence interval (CI) 2.88-3.87) and 6.05 (95% CI 5.04-7.26) for low SEP and low educational level, respectively. After adjusting for age, gender, hypertension, diabetes, dyslipidemia, abdominal obesity, smoking, alcohol intake and family history of cardiovascular disease, the figures were 1.23 (95% CI 1.04-1.43) and 1.54 (95% CI 1.23-1.85) for low SEP and low educational level, respectively. Conclusions: In a society in socioeconomic transition, low SEP and especially low educational level are risk factors for mortality even after adjusting for known mortality risk factors

Popperian epidemiology is a biomedical science tool based on the hypothesis-deductive method and the falsifiability of scientific hypotheses. This article explores the applicability of the refutationist logic tools in the analysis of a randomised controlled trial (RCT), the randomised Aldactone evaluation study (RALES). This was carried out by using bi-conditional modus-tollens arguments of the type (i) P-then-Q(n) and (ii) Q(n)-If-X(P), X(P) being a set of potential falsifiers of Q(n) as part of the explicit falsity-content of P. In this model, P is the main hypothesis and Q(n) one or more logical predictions to be tested. The X(P) argument represents inclusion criteria, exclusion criteria and conditional criteria of the RCT so every P-then-X(P) argument should be fulfilled in canonical form to corroborate P-then-Q(n). Thus, falsifiability of a RCT would be determined by the empirical content of the conditional argument Q(n)-If-X(P) and its external validity would be determined by the empirical content of X(P). In this way it would be possible to mathematically assess the external validity of a RCT if the observational predicates of the X(P) argument in a given population are known. According to this popperian model, applicability of the RCT results to clinical practice implies transferring of all its empirical content, in other words, the totality of its truth and falsity contents. Thus, to ignore the explicit falsity-content of a RCT such as RALES may jeopardise its potential benefits in clinical practice as suggested by recent studies.

In 1999 a great multi-site clinical trial known as the randomised Aldactone evaluation study (RALES) showed that the use of spironolactone importantly reduced complications attributable to chronic heart failure without major negative side effects. Recently, RALES has been questioned by a large scale observational study in the Ontario population. In contrast with predictions, the complications and mortality increased dramatically because of hyperkalaemia, reaching dimensions that from a public health perspective are comparable to an epidemic. This review analyses both researches in the light of Karl Popper’s science theory applying the modus tollens syllogism to the reality proposed by the main empirical enunciations that ensue from its epidemiological designs. RALES is deductively refuted because of the non-fulfillment of auxiliary assumptions that would act as reciprocal potential falsifiers in both studies, taking the logical form of a bi-conditional argument of the type: (a) P-then-Q and (b) Q-if-X P , X P being a set of potential falsifiers of Q as part of the explicit falsity content of P . From this popperian model, implications for clinical research are discussed.

Background: The San Francisco Project is a prospective study aiming to determine the most important cardiovascular risk factors in the Chilean population. Aim: To report the results of the San Francisco Project after a mean follow up of five years. Material and methods: Between 1997 and 1999, 920 subjects (aged 39.5 ± 16.3 years, 382 males), free of cardiovascular events, were examined to determine their cardiovascular risk factors. The prevalence of risk factors was compared with the Chilean National Health Survey. All non fatal cardiovascular events were registered until 2003. A logistic regression model including gender, obesity, family history, educational level and classical cardiovascular risk factors, was performed to identify independent predictors of cardiovascular events. Results: The prevalence of cardiovascular risk factors in the studied population was similar to that of the Chilean National Health Survey, except for serum lipid levels, that were lower in the latter. The mean follow up was 5.3 ± 0.3 years (range 4-6 years), and 26 cardiovascular events were registered. The independent predictors of these events were age, with a relative risk (RR) of 4.3 and 95% confidence intervals (CI) of 1.9 to 9.5 (p