Miguel A. Martinez-Beneito

Stroke mortality and trends from 1990 to 2006 in 39 countries from Europe and Central Asia: implications for control of high blood pressure

AIMS The aim of the present study was to extend our understanding of international trends in stroke and major sequelae in Europe and countries peripheral to Europe by assessing: (1) current mortality rates, (2) the most recent 15-year prevalence trends, and (3) the relationship between systolic blood pressure in community surveys and national stroke mortality. METHODS AND RESULTS Data were obtained from the World Health Organization (WHO www.who.int/whosis/database/mort/table.cfm), and represent national vital statistics as reported by 39 countries (European and Central Asian countries) using a standard format and population-based cardiovascular surveys. Total numbers of deaths by stroke (International Classification of Diseases 430-438, 444) and the age, sex-adjusted incidence rates were obtained and grouped according to three standard demographic categories: A, B, and C (WHO). A Bayesian linear mixed effect model was fitted to the annual mortality rates. Higher rates of stroke mortality were observed for B and C group countries as compared with those countries belonging to Group A (e.g. Bulgaria 273.9 and 281.1; Israel 37.7 and 45.4 per 100 000 men and women, respectively). Even though the mortality rates within the country groupings were relatively similar, countries with marked deviation from the average were observed, mainly in Groups B and C. Stroke mortality decreased sharply in Group A during the period of study; conversely it had increased substantially in Group B and to a lesser extent in Group C. For both sexes markedly higher rates were noted moving from west to east, with some exceptions. CONCLUSION We have entered a period of rapidly increasing international inequality in stroke risk, where countries with low adult mortality in the latter 20th century extended their downward trend and countries with moderate as well as high mortality have on average seen unprecedented increases in death rates from stroke.

Inequalities in mortality in small areas of eleven Spanish cities (the multicenter MEDEA project).

The objectives of this study are to identify inequalities in mortality among census tracts of 11 Spanish cities in the period 1996-2003 and to analyse the relationship between these geographical inequalities and socioeconomic deprivation. It is a cross-sectional ecological study where the units of analysis are census tracts. We obtained an index of socioeconomic deprivation and estimated SMR by each census tract using hierarchical Bayesian models which take into account the spatial structure. In the majority of the cities geographical patterns in total mortality were found in both sexes, which were similar to those for the index of socioeconomic deprivation. Among men, four specific causes of death (lung cancer, ischemic heart diseases, respiratory diseases and cirrhosis) were positively associated with deprivation in the majority of cities. Among women the specific causes diabetes and cirrhosis were positively associated, while lung cancer was negatively associated with deprivation. The excess of mortality related with deprivation was 59,445 deaths among men and 23,292 among women. These results highlight the importance of intra-urban inequalities in health.

Bayesian Markov switching models for the early detection of influenza epidemics

The early detection of outbreaks of diseases is one of the most challenging objectives of epidemiological surveillance systems. In this paper, a Markov switching model is introduced to determine the epidemic and non-epidemic periods from influenza surveillance data: the process of differenced incidence rates is modelled either with a first-order autoregressive process or with a Gaussian white-noise process depending on whether the system is in an epidemic or in a non-epidemic phase. The transition between phases of the disease is modelled as a Markovian process. Bayesian inference is carried out on the former model to detect influenza epidemics at the very moment of their onset. Moreover, the proposal provides the probability of being in an epidemic state at any given moment. In order to validate the methodology, a comparison of its performance with other alternatives has been made using influenza illness data obtained from the Sanitary Sentinel Network of the Comunitat Valenciana, one of the 17 autonomous regions in Spain.

Preventable avoidable mortality: Evolution of socioeconomic inequalities in urban areas in Spain, 1996–2003

This study describes the inequalities in preventable avoidable mortality in relation to socioeconomic levels and analyses their evolution during the period 1996-2003 in the cities of Alicante, Castellon and Valencia. Four causes of preventable avoidable mortality were analysed according to sex: malignant tumour of the trachea, bronchus and lung, cirrhosis and other chronic diseases of the liver, motor vehicle accidents and AIDS, which had caused the death of non-institutionalised residents in the three cities during the period 1996-2003. The different census tracts were grouped into three socioeconomic levels. In general, socioeconomic inequalities in preventable avoidable mortality remain constant in time, except the ones caused by AIDS in Valencia, where they increase for men. Some census tracts in the three cities where the study was carried out were found to have significantly higher preventable mortality rates, and therefore require intervention.

Childhood cancer incidence and survival in Spain

BACKGROUND This article affords an overview of the patterns and time trends of childhood cancer incidence (1983-2002) and survival (1991-2002) in Spain. PATIENTS AND METHODS A population-based study was conducted, including 5936 cases for incidence and 3257 for survival analyses. Differences in incidence were tested with the standardised incidence ratio. Trends were analysed for all tumours, and for all malignant, haematological, central nervous system (CNS) (all and only malignant) and other solid tumours. Incidence trends were analysed using Poisson and Bayesian joinpoint models. Observed, relative and age-adjusted survival rates were calculated, and trends were tested using the log-rank test. RESULTS The incidence pattern in Spain was similar to that in Europe. Rates, both overall and for leukaemias, lymphomas, CNS, soft tissue and, remarkably, for sympathetic nervous system and bone tumours, were high. Upward incidence trends were present for all tumour groups. All groups, except solid tumours (excluding CNS), displayed a change-point centred around 1990-95, after which the trend stopped rising. Five-year survival increased significantly across the period for all groups, except for CNS tumours. Recent survival results were in line with Italy, the UK and the European average. CONCLUSIONS To confirm these results, ongoing surveillance of incidence and survival trends, and studies targeting specific tumours are called for.

Métodos para la suavización de indicadores de mortalidad: aplicación al análisis de desigualdades en mortalidad en ciudades del Estado español (Proyecto MEDEA)

Aunque la experiencia en el estudio de las desigualdades en la mortalidad en las ciudades espanolas es amplia, quedan grandes nucleos urbanos que no han sido investigados utilizando la seccion censal como unidad de analisis territorial. En este contexto se situa el proyecto coordinado «Desigualdades socioeconomicas y medioambientales en la mortalidad en ciudades de Espana. Proyecto MEDEA», en el cual participan 10 grupos de investigadores de Andalucia, Aragon, Cataluna, Galicia, Madrid, Comunitat Valenciana y Pais Vasco. Cabe senalar cuatro particularidades: a) se utiliza como area geografica basica la seccion censal; b) se emplean metodos estadisticos que tienen en cuenta la estructura geografica de la region de estudio para la estimacion de riesgos; c) se aprovechan las oportunidades que ofrecen 3 fuentes de datos complementarias (informacion sobre contaminacion atmosferica, informacion sobre contaminacion industrial y registros de mortalidad), y d) se emprende un analisis coordinado de gran alcance, favorecido por la implantacion de la redes tematicas de investigacion. El objetivo de este trabajo es explicar los metodos para la suavizacion de indicadores de mortalidad en el proyecto MEDEA. El articulo se centra en la metodologia y los resultados del modelo de mapa de enfermedades de Besag, York y Mollie (BYM). Aunque en el proyecto se han suavizado, mediante el modelo BYM, las razones de mortalidad estandarizadas (RME) correspondientes a 17 grandes grupos de causas de defuncion y 28 causas especificas, aqui se aplica esta metodologia a la mortalidad por cancer de traquea, de bronquios y de pulmon en ambos sexos en la ciudad de Barcelona durante el periodo 1996-2003. Como resultado se aprecia un diferente patron geografico en las RME suavizadas en ambos sexos. En los hombres se observan unas RME mayores que la unidad en los barrios con mayor privacion socioeconomica. En las mujeres este patron se observa en las zonas con un mayor nivel socioeconomico.

Cancer mortality inequalities in urban areas: a Bayesian small area analysis in Spanish cities

BackgroundIntra-urban inequalities in mortality have been infrequently analysed in European contexts. The aim of the present study was to analyse patterns of cancer mortality and their relationship with socioeconomic deprivation in small areas in 11 Spanish cities.MethodsIt is a cross-sectional ecological design using mortality data (years 1996-2003). Units of analysis were the census tracts. A deprivation index was calculated for each census tract. In order to control the variability in estimating the risk of dying we used Bayesian models. We present the RR of the census tract with the highest deprivation vs. the census tract with the lowest deprivation.ResultsIn the case of men, socioeconomic inequalities are observed in total cancer mortality in all cities, except in Castellon, Cordoba and Vigo, while Barcelona (RR = 1.53 95%CI 1.42-1.67), Madrid (RR = 1.57 95%CI 1.49-1.65) and Seville (RR = 1.53 95%CI 1.36-1.74) present the greatest inequalities. In general Barcelona and Madrid, present inequalities for most types of cancer. Among women for total cancer mortality, inequalities have only been found in Barcelona and Zaragoza. The excess number of cancer deaths due to socioeconomic deprivation was 16,413 for men and 1,142 for women.ConclusionThis study has analysed inequalities in cancer mortality in small areas of cities in Spain, not only relating this mortality with socioeconomic deprivation, but also calculating the excess mortality which may be attributed to such deprivation. This knowledge is particularly useful to determine which geographical areas in each city need intersectorial policies in order to promote a healthy environment.

On Sampling Strategies in Bayesian Variable Selection Problems With Large Model Spaces

One important aspect of Bayesian model selection is how to deal with huge model spaces, since the exhaustive enumeration of all the models entertained is not feasible and inferences have to be based on the very small proportion of models visited. This is the case for the variable selection problem with a moderately large number of possible explanatory variables considered in this article. We review some of the strategies proposed in the literature, from a theoretical point of view using arguments of sampling theory and in practical terms using several examples with a known answer. All our results seem to indicate that sampling methods with frequency-based estimators outperform searching methods with renormalized estimators. Supplementary materials for this article are available online.

Spatial Analysis of the Relationship between Mortality from Cardiovascular and Cerebrovascular Disease and Drinking Water Hardness

Previously published scientific papers have reported a negative correlation between drinking water hardness and cardiovascular mortality. Some ecologic and case–control studies suggest the protective effect of calcium and magnesium concentration in drinking water. In this article we present an analysis of this protective relationship in 538 municipalities of Comunidad Valenciana (Spain) from 1991–1998. We used the Spanish version of the Rapid Inquiry Facility (RIF) developed under the European Environment and Health Information System (EUROHEIS) research project. The strategy of analysis used in our study conforms to the exploratory nature of the RIF that is used as a tool to obtain quick and flexible insight into epidemiologic surveillance problems. This article describes the use of the RIF to explore possible associations between disease indicators and environmental factors. We used exposure analysis to assess the effect of both protective factors—calcium and magnesium—on mortality from cerebrovascular (ICD-9 430–438) and ischemic heart (ICD-9 410–414) diseases. This study provides statistical evidence of the relationship between mortality from cardiovascular diseases and hardness of drinking water. This relationship is stronger in cerebrovascular disease than in ischemic heart disease, is more pronounced for women than for men, and is more apparent with magnesium than with calcium concentration levels. Nevertheless, the protective nature of these two factors is not clearly established. Our results suggest the possibility of protectiveness but cannot be claimed as conclusive. The weak effects of these covariates make it difficult to separate them from the influence of socioeconomic and environmental factors. We have also performed disease mapping of standardized mortality ratios to detect clusters of municipalities with high risk. Further standardization by levels of calcium and magnesium in drinking water shows changes in the maps when we remove the effect of these covariates.

Socio-economic inequalities in mortality due to injuries in small areas of ten cities in Spain (MEDEA Project)

OBJECTIVES To analyse socio-economic inequalities in mortality due to injuries among census tracts of ten Spanish cities by sex and age in the period 1996-2003. METHODS This is a cross-sectional ecological study where the units of analysis are census tracts. The study population consisted of people residing in the cities during the period 1996-2003. For each census tract we obtained an index of socio-economic deprivation, and estimated standardized mortality ratios using hierarchical Bayesian models which take into account the spatial structure of the data. RESULTS In the majority of the cities, the geographical pattern of total mortality from injuries is similar to that of the socio-economic deprivation index. There is an association between mortality due to injuries and the deprivation index in the majority of the cities which is more important among men and among those younger than 45 years. In these groups, traffic injuries and overdoses are the causes most often associated with deprivation in the cities. The percentage of excess mortality from injuries related to socio-economic deprivation is higher than 20% in the majority of the cities, the cause with the highest percentage being drug overdose. CONCLUSIONS In most cities, there are socio-economic inequalities in mortality due to overdose and traffic injuries. In contrast, few cities have found association between suicide mortality and deprivation. Finally, no association was found between deprivation and deaths due to falls. Inequalities are higher in men and those under 45 years of age. These results highlight the importance of intra-urban inequalities in mortality due to injuries.