Showing papers by "Stephen S Lim published in 2011"

Net Benefits: A Multicountry Analysis of Observational Data Examining Associations between Insecticide- Treated Mosquito Nets and Health Outcomes

Abstract: Background: Several sub-Saharan African countries have rapidly scaled up the number of households that own insecticidetreated mosquito nets (ITNs). Although the efficacy of ITNs in trials has been shown, evidence on their impact under routine conditions is limited to a few countries and the extent to which the scale-up of ITNs has improved population health remains uncertain. Methods and Findings: We used matched logistic regression to assess the individual-level association between household ITN ownership or use in children under 5 years of age and the prevalence of parasitemia among children using six malaria indicator surveys (MIS) and one demographic and health survey. We used Cox proportional hazards models to assess the relationship between ITN household ownership and child mortality using 29 demographic and health surveys. The pooled relative reduction in parasitemia prevalence from random effects meta-analysis associated with household ownership of at least one ITN was 20% (95% confidence interval [CI] 3%–35%; I 2 = 73.5%, p,0.01 for I 2 value). Sleeping under an ITN was associated with a pooled relative reduction in parasitemia prevalence in children of 24% (95% CI 1%–42%; I 2 = 79.5%, p,0.001 for I 2 value). Ownership of at least one ITN was associated with a pooled relative reduction in mortality between 1 month and 5 years of age of 23% (95% CI 13–31%; I 2 = 25.6%, p.0.05 for I 2 value). Conclusions: Our findings across a number of sub-Saharan African countries were highly consistent with results from previous clinical trials. These findings suggest that the recent scale-up in ITN coverage has likely been accompanied by significant reductions in child mortality and that additional health gains could be achieved with further increases in ITN coverage in populations at risk of malaria. Please see later in the article for the Editors’ Summary.

Management of diabetes and associated cardiovascular risk factors in seven countries: a comparison of data from national health examination surveys

Abstract: OBJECTIVE: To examine the effectiveness of the health system response to the challenge of diabetes across different settings and explore the inequalities in diabetes care that are attributable to socioeconomic factors. METHODS: We used nationally representative health examination surveys from Colombia, England, the Islamic Republic of Iran, Mexico, Scotland, Thailand and the United States of America to obtain data on diagnosis, treatment and control of hyperglycaemia, arterial hypertension and hypercholesterolaemia among individuals with diabetes. Using logistic regression, we explored the socioeconomic determinants of diagnosis and effective case management. FINDINGS: A substantial proportion of individuals with diabetes remain undiagnosed and untreated, both in developed and developing countries. The figures range from 24% of the women in Scotland and the USA to 62% of the men in Thailand. The proportion of individuals with diabetes reaching treatment targets for blood glucose, arterial blood pressure and serum cholesterol was very low, ranging from 1% of male patients in Mexico to about 12% in the United States. Income and education were not found to be significantly related to the rates of diagnosis and treatment anywhere except in Thailand, but in the three countries with available data insurance status was a strong predictor of diagnosis and effective management, especially in the United States. CONCLUSION: There are many missed opportunities to reduce the burden of diabetes through improved control of blood glucose levels and improved diagnosis and treatment of arterial hypertension and hypercholesterolaemia. While no large socioeconomic inequalities were noted in the management of individuals with diabetes, financial access to care was a strong predictor of diagnosis and management.

High total serum cholesterol, medication coverage and therapeutic control: an analysis of national health examination survey data from eight countries

Abstract: OBJECTIVE: To determine the fraction of individuals with high total serum cholesterol who get diagnosed and effectively treated in eight high- and middle-income countries METHODS: Using data from nationally representative health examination surveys conducted in 1998-2007, we studied a probability sample of 79 039 adults aged 40-79 years from England, Germany, Japan, Jordan, Mexico, Scotland, Thailand and the United States of America For each country we calculated the prevalence of high total serum cholesterol (total serum cholesterol > 62 mmol/l or > 240 mg/dl) and the mean total serum cholesterol level We also determined the fractions of individuals being diagnosed, treated with cholesterol-lowering medication and effectively controlled (total serum cholesterol < 62 mmol/l or < 240 mg/dl) FINDINGS: The proportion of undiagnosed individuals was highest in Thailand (78%; 95% confidence interval, CI: 74-82) and lowest in the United States (16%; 95% CI: 13-19) The fraction diagnosed but untreated ranged from 9% in Thailand (95% CI: 8-11) to 53% in Japan (95% CI: 50-57) The proportion being treated who had attained evidence of control ranged from 4% in Germany (95% CI: 3-5) to 58% in Mexico (95% CI: 54-63) Time series estimates showed improved control of high total serum cholesterol over the past two decades in England and the United States CONCLUSION: The percentage of people with high total serum cholesterol who are effectively treated remains small in selected high- and middle-income countries Many of those affected are unaware of their condition Untreated high blood cholesterol represents a missed opportunity in the face of a global epidemic of chronic diseases

High Total Serum Cholesterol, Medication Coverage and Therapeutic Control: An Analysis of National Health Examination Survey Data from Eight countries/Cholesterol Serique Total Eleve, Couverture Pharmaceutique et Controle Therapeutique: Une Analyse Des Donnees Nationales D'enquete Sur Les Examens De Sante Emanant De Huit Pays/ Concentracion Serica De Colesterol Elevada, Cobertura Farmaceutica

Abstract: Introduction Cardiovascular disease caused over 18 million deaths in the world in 2005. (1) Of these deaths, eight million (44%) occurred in people under 60 years of age and 80% took place in low- and middle-income countries. (1,2) In response, the World Health Organization (WHO) has set a goal of reducing the global rate of death from chronic diseases by 2% a year up to 2015. (3) This goal rests on the recognition that throughout the world deaths from cardiovascular causes are attributable to a few modifiable risk factors, most importantly high blood pressure, smoking and high total serum cholesterol. (4,5) Lowering total serum cholesterol levels is an ideal strategy for reducing the burden of cardiovascular disease. Potent, safe and highly effective cholesterol-lowering medication is available in the form of statins, (6) and there are many low-cost methods for identifying those who need to lower their serum cholesterol. (7,8) Modelling studies suggest that lowering total serum cholesterol, either by treating elevated total serum cholesterol alone or by managing multiple risk factors, is cost-effective in many low- and middle-income countries. (9) While the use of cholesterol-lowering medication is considered important in reducing the burden of cardiovascular disease, differences in the way various health systems are implementing this strategy are not well understood. (10,11) Comparing individual studies is difficult because the definition of a high blood cholesterol level varies among studies and, until recently, population-wide data has been lacking for many places. The growing number of national health examination surveys that measure total serum cholesterol provides an opportunity to ascertain how well cholesterol-lowering medication is being-delivered to populations at risk of cardiovascular disease. (12) Using microdata from multiple national health examination surveys in eight countries, we have estimated the proportion of the population diagnosed with high total serum cholesterol, on treatment with cholesterol-lowering medication, and with evidence of therapeutic control. Methods Search strategy In 2008, we systematically searched the following for nationally representative health examination surveys performed since 1997: Google Scholar and PubMed (using relevant keywords), the WHO Global Infobase, (13) the WHO STEPwise approach to surveillance database (14) and the European Health Interview Surveys and Health Examination Surveys database. (15) We identified surveys that measured total serum cholesterol and that asked respondents if they used cholesterol-lowering medication. Individual-level data was downloaded from agency web sites when publicly available or obtained through formal application procedures and by contacting study authors. Survey characteristics The following national health examination surveys met our criteria: Germany (1998), Japan (2000), Scotland (2003), Thailand (2004), the United States of America (2005-2006), England (2006), Mexico (2006) and Jordan (Jordan Ministry of Health, unpublished data, 2007). (16-22) Our study included five high-income countries, one upper-middle-income country and two lower-middle-income countries. Table 1 shows the year in which the surveys were conducted, the questions used in these surveys for the self-reported diagnosis of high total serum cholesterol and the self-reported use of cholesterol-lowering medication. Most surveys did not differentiate between prescribed and over-the-counter medications or between statin and nonstatin medication. Enzyme-based automated methods were used in all surveys to measure total serum cholesterol levels. The guidelines of the United States Centers for Disease Control and Prevention and WHO were followed in all countries except Germany and Thailand, where national guidelines were observed. Blood tests were performed in a central laboratory in all countries except Thailand, which relied on five regional university laboratories. …

Implementation and progress of an inclusive primary health care model in Guatemala: coverage, quality, and utilization

Abstract: Effective primary health care modelsthat track data at an individual level andaim to reach underserved groups are apriority for the global health communityand are considered a means to increaseservice coverage and improve health out-comes (1, 2). There are few examples ofcomprehensive primary health care mod-els in the region that have been imple-mented over a significant time periodand that have data that were rigorouslyrecorded, analyzed, and disseminated.At a national level, Cuba, Costa Rica, andBrazil present some of the most long-term experiences; other, more localizedexperiences also have important lessons(3–8). It is important to share lessonslearned from implementation experi-ences to build on the knowledge base atnational, regional, and global levels.Despite being a country that hasachieved relatively strong economic indi-cators, Guatemala has lagged behindother countries in the region in terms ofhealth indicators and service deliverymeasures. With an estimated 49.8% of

Recalibration of the Framingham Equations in the Thai Population

Abstract: We derived equations for predicting cardiovascular disease (CVD) risks for Thai men and women, separately, over a specific time period using associations between risk factors and CVD events from the Framingham cohort study. The equations were recalibrated against the cumulative risks estimated for Thailand. Equations were developed separately for predicting risks of ischemic heart disease (IHD) and stroke. Recalibration of the Framingham equations reduced the CVD risks predicted for Thai men by 97% and for Thai women by 10%. The correction was largest at younger ages. In older women, recalibration increased the predicted risk. When compared with an existing equation for Thai men our recalibrated Framingham equation produced similar predictions for CVD risks over 8 years. However, the recalibrated Framingham equations are more flexible because they can be used for predicting risks over any time span and for women and men.