Hypertension in developing countries

Population surveys carried out since the 1970s in 15 developing countries including 23 population groups show that the prevalence of hypertension ranges from as low as 1% in some African countries to over 30% in Brazil. A trend analysis of the mortality statistics for 35-74 year-olds from 16 countries in which data are available shows a downward trend in mortality from hypertension and cerebrovascular diseases in most of these countries. In spite of the current low prevalence in some countries, the total number of hypertensives in the developing world is high, and a cost assessment of possible antihypertensive drug treatment indicates that developing countries cannot afford the same drug treatment levels as developed countries.     

中国高血压防治指南2010

目的了解上海市自报高血压者的膳食摄入与血压控制情况的关系,为开展膳食指导提供依据。方法利用2013年上海市慢性病及其危险因素监测数据,采用多因素logistic回归分析膳食摄入情况与血压控制情况的关系。结果6 327名研究对象纳入分析,上海市自报高血压者血压控制率为37.62%。多因素分析发现,与推荐摄入量相比,水产类摄入不足(OR=0.884,95%CI：0.782~1.000)或超量(OR=0.820,95%CI：0.689~0.977)以及畜禽类摄入不足(OR=0.881, 95%CI:0.789~0.983)与高血压控制率低相关。结论上海市自报高血压者膳食结构不尽合理,应加强居民膳食指南的宣贯,倡导合理膳食,适量摄入水产品、瘦肉、禽肉等优质蛋白,以有效控制血压。     

Urbanization and health in developing countries

In developing countries the level of urbanization is expected to increase to 39.5% by the end of this century and to 56.9% by 2025. The number of people living in slums and shanty towns represent about one-third of the people living in cities in developing countries. This article focuses upon these poor urban populations and comments upon their lifestyle and their exposure to hazardous environmental conditions which are associated with particular patterns of morbidity and mortality. The concept of marginality has been used to describe the lifestyle of the urban poor in developing countries. This concept is critically examined and it is argued that any concept of the urban poor in developing countries being socially, economically or politically marginal is a myth. However, it can certainly be claimed that in health terms the urban poor are marginal as demonstrated by some of the studies reviewed in this article. Most studies of the health of the urban poor in developing countries concentrate on the environmental conditions in which they live. The environmental conditions of the urban poor are one of the main hazards of the lifestyle of poor urban residents. However, other aspects of their way of life, or lifestyle, have implications for their health. Issues such as smoking, diet, alcohol and drug abuse, and exposure to occupational hazards, have received much less attention in the literature and there is an urgent need for more research in these areas.     

Nutrition and aging in developing countries

The number of individuals aged 60 y or older is projected to double as a proportion of the world's population and to more than triple in number over the next 50 y. These changes will be most dramatic in the less developed countries, where the transition from a young to old age structure will be more compressed in time than it has been for developed countries. At the same time, there is evidence of a characteristic sequence of changes in diet and declines in physical activity associated with social and economic change. Diets are becoming higher in fats, animal products, and refined foods and lower in fiber, contributing to rapidly increasing prevalences of obesity and type 2 diabetes. The number of people with diabetes in developing countries is projected to almost triple by the year 2025. Hypertension and vascular disease are also rapidly becoming more prevalent. Evidence that lower birth weights are associated with greater likelihood of adult obesity and chronic disease underscores the magnitude of risk in these countries. Few programs or institutions currently exist to address the problems of the growing elderly population. The social changes that accompany urbanization will likely increase nutritional risk for this group. Despite lower energy intakes with age, elderly have higher requirements for several micronutrients, making them vulnerable to deficiencies that further aggravate chronic conditions. To reduce the impending burden of disease and disability worldwide, urgent action is needed to understand and to address the nutritional needs of the aging population.     

Animal welfare and developing countries: opportunities for trade in high-welfare products from developing countries

Discussion on the potential for developing countries to develop trade in niche markets such as higher welfare standards has been highlighted with moves by the World Organisation for Animal Health (OIE) to set internationally agreed standards for animal welfare. This paper examines the existing and potential trade in value-added higher welfare products using case studies in the beef and poultry sectors from three countries in Africa, Asia and Latin America. It shows that at present there is only a small trade in these products but that this can have a major effect at a national level. In the beef export trade from Namibia, the existence of the only assurance scheme in Africa setting standards in hygiene, veterinary care and animal welfare has created a trusted, safe and healthy product and ensured that Namibia has grown into Africa's largest exporter of beef to the European Union. In Thailand, the broiler industry, which has enjoyed annual growth in the past 15 years, is developing value-added products to develop markets to counter competition from other countries. The development and implementation of standards for organic products in both Thailand and Argentina over the past decade have also resulted in growth in the export markets of these products. The paper concludes that there is growth potential for the sectors in all three markets which can be assisted by the development of OIE baseline standards.     

Maternal immunisation in developing countries

Maternal immunisation could help to prevent the 2-3 million neonatal and early infant deaths that occur in the developing world each year. Determining the causes of neonatal and early infant deaths in developing countries is difficult as most occur at home. However, it is likely that at least half are due to infections, several of which might be prevented by maternal immunisation. Even in poor countries with few health facilities, a high percentage of pregnant women attend an antenatal clinic at least once during pregnancy. Thus, an effective delivery system for maternal immunisation already exists and, because of the success of maternal tetanus immunisation, this approach to the prevention of serious illness or death in young infants is widely accepted by the general population. However, the high prevalence of HIV and malaria found in pregnant women in some parts of the developing world, especially sub-Saharan Africa, could have an effect on the efficacy of maternal immunisation as both of these infections adversely affect placental function. Nevertheless, the potential of maternal immunisation to prevent early infant deaths in developing countries needs to be fully explored. The incidence of pneumococcal infections is high in many developing countries and about 25% of these infections occur at an age before protection could be anticipated following vaccination with a pneumococcal conjugate vaccine in infancy. Thus, a strong case can be made for a trial of the effectiveness of maternal immunisation with a pneumococcal vaccine in preventing serious illness or death in young infants in developing countries.     

Maternal mortality in developing countries

The authors of this letter respond to earlier letters prepared in response to their article on maternal mortality in developing countries. It is conceded that maternal mortality is high in India and Bangladesh; however, statistics from Gambia are based on small populations and are therefore inconclusive. It is noted that a 7-year survey of 4000 households in Machakos, Kenya, where 73% of deliveries occurred at home, yielded a maternal mortality rate of only 0.8/1000 deliveries. Finally, it is asserted that the measurement traditionally used in estimating maternal mortality for many African countries (ratio of recorded maternal deaths to recorded deliveries) is misleading. Maternal deaths are more likely than deliveries to be recorded. In Niger, the number of maternal deaths increased from 1980 (374) to 1982 (484). The ratio of maternal deaths to expected live births also increased from 135 to 166/100,000, whereas the traditionally calculated maternal mortality rate decreased from 519 to 420/100,000 due to changes in the denominators. It is recommended that health authorities of African countries such as Niger consider setting an absolute number of maternal deaths below which they would try to bring the current toll.     

Knowledge translation in developing countries

There is increasing evidence that the application of knowledge in developing countries is failing. One reason is the woeful shortage of health workers, but as this is redressed, it is also crucial that we have an evidence base of what works to minimize the "know-do gap." The World Health Organization and other international organizations are actively building momentum to promote research to determine effective strategies for knowledge translation (KT). At this time, the evidence base for the effectiveness of those strategies is not definitive in developed countries and is relatively sparse in developing countries. It appears, however, that the effectiveness of these strategies is highly variable and dependent on the setting, and success hinges on whether the strategies have been tailored. A useful framework to provide direction for tailoring interventions is the Ottawa Model of Research Use (OMRU). Underlying OMRU is the principle that success rests with tailoring KT strategies to the salient barriers and supports found within the setting. The model recommends that barriers and supports found in the practice environment or as characteristics of potential adopters and the evidence-based innovation or research evidence be assessed and then the KT strategy tailored and executed. The model also recommends that whether the research has been applied and has resulted in improved health outcomes should be measured. Studies in developing countries, although few, illustrate that the OMRU approach may be a valid method of tackling the challenges of KT strategies to improve health care in developing countries.     

中国出生缺陷预防策略的思考

  目的  了解叶酸增补认知对叶酸服用的影响,为妇幼保健部门提高叶酸增补干预效率、改善出生结局提供数据支撑。  方法  分析2016年7 — 8月在陕西省10个地级市和杨凌示范区开展的横断面调查数据,采用问卷调查方法对1 495名近3年有过生育史或正在怀孕的育龄妇女围孕期叶酸服用状况和叶酸增补认知情况进行调查,采用log-binomial模型分析叶酸增补认知对叶酸服用状况的影响,估计现患比（prevalence ratio）及其95 % CI,衡量叶酸增补认知状况对叶酸服用的影响程度。  结果  本研究纳入育龄妇女1 495人,平均年龄29.27岁,叶酸服用率为84.10 %。叶酸增补认知方面,围孕期增补叶酸的知晓率为86.49 %,增补叶酸预防神经管畸形（NTDs）的知晓率为57.11 %,叶酸免费领取的知晓率为71.35 %。随着协变量的引入,认知水平和叶酸服用之间始终呈现正相关。控制了所有可能的因素后,知晓围孕期服用叶酸对叶酸服用影响的PR值为2.97（95 % CI = 2.33～3.93）,知晓叶酸预防NTDs的PR值为1.05（95 % CI = 1.01～1.10）。敏感性分析显示,知晓围孕期需要服用叶酸和知晓叶酸预防NTDs在不同人群间对叶酸服用均具有显著影响（P < 0.05）。  结论  认知是影响叶酸服用的独立因素,特别是知晓孕期服用叶酸和知晓叶酸预防NTDs对叶酸服用具有显著影响。认知因素在促进叶酸服用方面具有重要价值。     

Maternal mortality in developing countries

The author challenges the recent claims of Thuriaux and Lamotte that hospital-based statistics of maternal mortality overestimate national maternal mortality since maternal deaths are more likely to be recorded than births. It is argued, instead, that the key issue is the level of coverage of births by health institutions. If such coverage is low, as it is in most African countries (average of 34%), the population-based maternal mortality ratio will also be low since it is calculated as the product of institutional maternal mortality ratio and obstetric coverage by institutions assuming that coverage of maternal deaths is 100%. The lower the proportion of births covered by institutions, the more uncertain this estimate. Obstetric coverage in Niger increased from 26% in 1980 to 39% in 1982. Thus, even though the number of maternal deaths in health facilities increased from 373 to 484 in this period, the institutional maternal mortality ratio decreased from 519 to 420/100,000 live births. On the other hand, maternal mortality estimated on the basis of expected births increased from 135 to 166. It is likely that the increased coverage of institutional births also improved recording of maternal deaths. Thus, it is misleading to use absolute number of deaths if changes in obstetric coverage are not taken into account.     

Paraquat in developing countries.

The herbicide paraquat is considered safe by industry and the bulk of regulators worldwide. However, determinants of exposure from 30 years ago persist in developing countries. Little is known about systemic absorption from occupational exposures. The relationships between exposure determinants, levels of external exposure, biomarkers of exposure, and outcomes are not clear. High rates of severe acute poisonings have been documented. In addition, topical injuries occur in as many as 50% of exposed workers. Non-worker populations are also at risk, particularly children. Long-term and delayed health effects include Parkinson's disease, lung effects, and skin cancer. Regulatory agencies have not fully recognized either the inherent toxicity of paraquat or the particular risks derived from exposures in developing countries. Independent risk assessment in the developing-country context and application of the precautionary principle are necessary to prevent adverse effects of dangerous pesticides in susceptible populations.