Rural-urban differentials in pregnancy-related mortality in Zambia: estimates using data collected in a census

Background

The use of census data to measure maternal mortality is a recent phenomenon, implemented in settings with non-functional vital registration systems and driven by needs for trend data. The 2010 round of population and housing censuses recorded a significant increase in the number of countries collecting maternal mortality data. The objective of this study was to estimate rural-urban differentials in pregnancy-related mortality in Zambia using census data.

Methods

We used data from the Zambia 2000 and 2010 censuses. Both censuses recorded the female population by age, the number of children ever born, and live births 12 months prior to the census. The 2010 census further recorded, by age, household, and pregnancy-related deaths 12 months prior to the census. We evaluated and adjusted recorded live births using the cohort Parity Fertility ratio method, and household deaths using deaths distribution methods (General Growth Balance and Synthetic Extinct Generation). Adult female mortality and pregnancy-related mortality for rural and urban areas were estimated for the period October 2009 to October 2010.

Results

Data evaluation showed errors in recorded population age, age-at-death, live births, and deaths, and appropriate adjustments were made. Adjusted adult female mortality was high; an adolescent aged 15 years had a one-in-three chance of dying before her 50th birthday in rural areas and one-in-four chance in urban areas. Pregnancy-related deaths comprised 15.3 % of all deaths among reproductive-age women overall; 17.9 % in rural areas and 9.8 % in urban areas. The pregnancy-related mortality ratio for the period was 789 deaths/100,000 live births overall: 960/100,000 live births in rural areas and 470/100,000 live births in urban areas.

Conclusions

Census-based estimates show very high adult female mortality and particularly high pregnancy-related mortality in both rural and urban areas of Zambia 12 months prior to the 2010 census. Future censuses should pay greater attention to strategies for improving data quality.

     

Estimating obstetric mortality from pregnancy-related deaths recorded in demographic censuses and surveys

Demographic surveys and censuses often record pregnancy-related deaths, defined as those occurring during the maternal risk period (pregnancy, delivery, and six weeks postpartum), but do not include cause of death. This study presents a method for estimating obstetric mortality from pregnancy-related deaths data. Calculations are based on multiple-decrement life tables, and data needed are simply age-specific fertility and mortality rates that are commonly available in Demographic and Health Survey (DHS) or census data, and an estimate of the relative risk of death from nonobstetric causes during the maternal risk period. The method is tested on 59 DHS surveys from Africa. Results show that, on average, less than half of the pregnancy-related deaths are attributable to obstetric causes. This proportion varies with the level of mortality and fertility, and in particular with the prevalence of HIV in the population.     

Estimating disease prevalence using census data

We describe a method of working on publicly available data to estimate disease prevalence in small geographic areas using Helicobacter pylori as a model infection. Using data from the Third National Health and Nutrition Examination Survey, risk parameters for H. pylori infection were obtained by logistic regression and validated by predicting 737.5 infections in an independent cohort with 736 observed infections. The prevalence of H. pylori infection in the San Francisco Bay Area was estimated with the probabilities obtained from a predictive logistic model, using risk parameters with individual-level 1990 U.S. Census data as input. Predicted H. pylori prevalence was also compared to gastric cancer incidence obtained from the Northern California Cancer Center and showed a positive correlation with gastric cancer incidence (P<0.001, R2=0.87), and no statistically significant association with other malignancies. By exclusively using publicly available data, these methods may be applied to selected conditions with strong demographic predictors.     

Mesigyna once-a-month combined injectable contraceptive: experience in Latin America

A phase III clinical study was carried out among 534 fertile Latin American women to evaluate cycle control, side effects, and contraceptive efficacy of a once-a-month combined injectable, Mesigyna, consisting of 50 mg norethisterone enanthate and 5 mg estradiol valerate. The pregnancy rate at 1 year was 0 per 100 woman-years for a total experience of 4688 woman-months. The overall discontinuation rate at one year was 17.9%. Discontinuation rate for bleeding problems was 5.1%. The Colombian women had a significant increase (p <0.001) in bleeding problems compared to other countries. The discontinuation rate for amenorrhea was 1.1%. There were no significant differences between the groups regarding discontinuation for other medical or non-medical reasons. Mean weight gain after one year of use was 1.02 kg. Mesigyna is an appropiate once-a-month injectable contraceptive for Latin American women since it is highly effective and its perception of normal menstrual bleeding is of importance in the Latin American population.     

Estimating mortality using data from civil registration: a cross-sectional study in India

ObjectiveTo analyse the design and operational status of India’s civil registration and vital statistics system and facilitate the system’s development into an accurate and reliable source of mortality data.MethodsWe assessed the national civil registration and vital statistics system’s legal framework, administrative structure and design through document review. We did a cross-sectional study for the year 2013 at national level and in Punjab state to assess the quality of the system’s mortality data through analyses of life tables and investigation of the completeness of death registration and the proportion of deaths assigned ill-defined causes. We interviewed registrars, medical officers and coders in Punjab state to assess their knowledge and practice.FindingsAlthough we found the legal framework and system design to be appropriate, data collection was based on complex intersectoral collaborations at state and local level and the collected data were found to be of poor quality. The registration data were inadequate for a robust estimate of mortality at national level. A medically certified cause of death was only recorded for 965 992 (16.8%) of the 5 735 082 deaths registered.ConclusionThe data recorded by India’s civil registration and vital statistics system in 2011 were incomplete. If improved, the system could be used to reliably estimate mortality. We recommend improving political support and intersectoral coordination, capacity building, computerization and state-level initiatives to ensure that every death is registered and that reliable causes of death are recorded – at least within an adequate sample of registration units within each state.     

Research on violence against women in Latin America: from blind empiricism to theory without data

Research on violence against women in Latin America presents an interesting paradox: while the number of studies is quite small, there also appears to be a sense that research on this topic has been exhausted, despite the lack of any definitive responses to the nature and causes of the problem. This results from the boom in studies with a strong empirical focus, lacking any basis in more general sociological theory. On the other hand, research using social theory tends to ignore the existing mediations between structural arrangements and any individual specific behavior, as well as the interactive nature of domestic violence. Meanwhile, empirical research presents inconsistent results and tends to run into methodological problems such as operational confusion, contradictory findings, and results and recommendations that are too obvious. New research designs must be developed to enrich the field and which are solidly based on the body of conceptual knowledge in social sciences, abandoning designs without theory and those which are merely statistical. Only then will it be possible to imagine the new research questions that the problem of violence requires.     

Estimating cancer mortality rates from SEER incidence and survival data.

A method to estimate site-specific cancer mortality rates using Surveillance, Epidemiology, and End Results (SEER) Program incidence and survival data is proposed, calculated, and validated. This measure, the life table-derived mortality rate (LTM), is the sum of the product of the probability of being alive at the beginning of an interval times the probability of dying of the cancer of interest during the interval times the annual age-adjusted incidence rate for each year that data have been collected. When the LTM is compared to death certificate mortality rates (DCM) for organ sites with no known misclassification problems, the LTM was within 10 percent of the death certificate rates for 13 of 14 organ sites. In the sites that have problems with the death certificate rates, there were major disagreements between the LTM and DCM. The LTM was systematically lower than the DCM for sites if there was overreporting on the death certificates, and the LTM was higher than the DCM for sites if there was underreporting. The limitations and applications of the LTM are detailed.     

Economic crisis and infant mortality in Latin America since the 1980's

In the present study, based on data from nine Latin American countries, we found evidence of an association between the economic crisis and infant mortality during the last decades. The paper initially review previous studies on this issue and shows the need for a greater research focus on shorter time intervals. We then describe the deterioration and unequal conditions among the countries based on trends in selected social and economic indicators and the evolution of infant mortality rates. According to our statistical analysis, infant mortality bore an inverse association to short-term economic variations. We also found a significant and negative correlation between decreasing infant mortality rates and increasing poverty. The economic crisis displayed effects of varying intensity among the countries we analyzed, with social inequality appearing as the most probable explanatory variable.     

Visceral Larva Migrans in Immigrants from Latin America

To determine whether increased migration is associated with an increase in incidence of toxocariasis (visceral larva migrans), we analyzed clinical data obtained from immigrants from Latin America. Although infection with Toxocara sp. roundworm larvae is distributed worldwide, seroprevalence is highest in tropical and subtropical areas.     

Obesity trends in Latin America: transiting from under- to overweight

Latin America is undergoing a rapid demographic and nutritional transition. A recent WHO/PAHO survey on obesity in the region revealed an increasing trend in obesity as countries emerge from poverty, especially in urban areas. In contrast, in middle income countries, obesity tends to decline as income increases; this is especially so in women. Dietary changes and increasing inactivity are considered the crucial contributory factors that explain this rise. The end result is a progressive rise in overweight and obesity, especially in low income groups who improve their income and buy high fat/high carbohydrate energy-dense foods. Intake of these foods increases to the detriment of grains, fruits and vegetables. Most aboriginal populations of the Americas have changed their diet and physical activity patterns to fit an industrialized country model. They now derive most of their diet from Western foods and live sedentary and physically inactive lives. Under these circumstances they develop high rates of obesity, insulin resistance and type 2 diabetes. Supplementary feeding programs are common in the region; the number of beneficiaries significantly exceeds the malnourished. Weight-for-age definition of undernutrition without assessment of length will overestimate the dimension of malnutrition and neglect the identification of stunted overweight children. Providing food to low income stunted populations may be beneficial for some, although it may be detrimental for others, inducing obesity especially in urban areas. Defining the right combination of foods/nutrients, education and lifestyle interventions that are required to optimize nutrition and health is a present imperative.     

The globalization of epidemiology: critical thoughts from Latin America

BACKGROUND: Epidemiology in Latin America, as in the rest of the world, has been developed for the purpose of contributing towards understanding the causes and determinants of the phenomena of health and disease in specific contexts. However, in that continent it has specific characteristics. METHODS: The paper explores epidemiology in the Latin American continent, emphasizing on the one hand epidemiology as a knowledge-producing, scientific discipline, and on the other hand, epidemiology in praxis, with its firm commitment to contributing towards transforming the health of the population. RESULTS: It has been possible to identify at least eight idiosyncrasies that characterize epidemiology in Latin America. It is being forged with a strong connection to the evolution of the discipline in an international context; however, it has its feet firmly planted in reality, seeking to extract from that reality elements that may contribute towards diminishing the serious health problems in that society. CONCLUSIONS: This paper presents a picture of the development of epidemiology in Latin America. It is very clear that as well as a lively, intense, intellectual debate, there is a frantic search for alternatives that will increase Latin American populations' possibilities of survival. However, one important aspect is that these two elements-theory and praxis-present consistent dialectic relationships and feedback; this is the main wealth of Latin American epidemiology.     

Social medicine then and now: lessons from Latin America

The accomplishments of Latin American social medicine remain little known in the English-speaking world. In Latin America, social medicine differs from public health in its definitions of populations and social institutions, its dialectic vision of "health-illness," and its stance on causal inference. A "golden age" occurred during the 1930s, when Salvador Allende, a pathologist and future president of Chile, played a key role. Later influences included the Cuban revolution, the failed peaceful transition to socialism in Chile, the Nicaraguan revolution, liberation theology, and empowerment strategies in education. Most of the leaders of Latin American social medicine have experienced political repression, partly because they have tried to combine theory and political practice--a combination known as "praxis." Theoretic debates in social medicine take their bearings from historical materialism and recent trends in European philosophy. Methodologically, differing historical, quantitative, and qualitative approaches aim to avoid perceived problems of positivism and reductionism in traditional public health and clinical methods. Key themes emphasize the effects of broad social policies on health and health care; the social determinants of illness and death; the relationships between work, reproduction, and the environment; and the impact of violence and trauma.