Total cardiovascular risk assessment and management using two prediction tools, with and without blood cholesterol.

INTRODUCTION: Over the last decade, total cardiovascular risk assessment and management has been recommended by cardiovascular prevention guidelines in most high-income countries and by WHO. Cardiovascular risk prediction charts have been developed based on multivariate equations of values of some well-known risk factors such as age, sex, smoking, systolic blood pressure and diabetes, including or omitting total blood cholesterol. OBJECTIVE: The objectives of this study were: to determine the distribution of cardiovascular risk in a Cuban population using the WHO/International Society of Hypertension risk prediction charts with and without cholesterol; and to assess applicability of the risk prediction tool without cholesterol in a middle-income country, by evaluating concordance between the two approaches and comparing projected drug requirements resulting from each (at risk thresholds of ≥20% and ≥30%) and for the single-risk-factor approach. METHODS: From April through December 2008, a cross-sectional study was conducted in 1287 persons (85.8% of the sample selected), aged 40-80 years living in a polyclinic catchment area of Havana, Cuba, based on the protocol and data from a WHO multinational study. The study used the two sets of the WHO and the International Society of Hypertension (WHO/ISH) risk prediction charts, with and without cholesterol. Percentages and means were calculated, as well as prevalence (%) of risk factors. The chi-square test was used to compare means (p ≤0.05). Concordance between the two prediction charts was calculated for different risk levels, using the chart with cholesterol as a reference. RESULTS: Using the risk assessment tools with and without cholesterol, 97.1% and 95.4% respectively of the study population were in the ten-year cardiovascular risk category of <20%, while 2.9% and 4.6% respectively were in the category of ≥20%. Risk categories were concordant in 88.1% of the population; overestimation was higher among the nonconcordant (136/153). When risk assessment did not include cholesterol, there was 2.6% (34/1287) overestimation of drug requirements and 0.5% (6/1287) underestimation, compared to estimates including cholesterol. CONCLUSION: Total cardiovascular risk assessment using the WHO/ISH charts without cholesterol could be a useful approach to predict cardiovascular risk in settings where cholesterol cannot be measured. This does not introduce overconsumption of drugs, but does enable better targeting of resources to those who are more likely to develop cardiovascular disease. KEYWORDS Cardiology, risk assessment, health risk appraisal, hypertension, health policy, cost savings, atherosclerosis, Cuba.

Cost effectiveness of strategies to combat cardiovascular disease, diabetes, and tobacco use in sub-Saharan Africa and South East Asia: mathematical modelling study.

OBJECTIVE: To determine the relative costs and health effects of interventions to combat cardiovascular disease, diabetes, and tobacco related disease in order to guide the allocation of resources in developing countries. DESIGN: Cost effectiveness analysis of 123 single or combined prevention and treatment strategies for cardiovascular disease, diabetes, and smoking by means of a lifetime population model. SETTING: Two World Health Organization sub-regions of the world: countries in sub-Saharan Africa with very high adult and high child mortality (AfrE) and countries in South East Asia with high adult and high child mortality (SearD). DATA SOURCES: Demographic and epidemiological data were taken from the WHO databases of mortality and global burden of disease. Estimates of intervention coverage, effectiveness, and resource needs were drawn from clinical trials, observational studies, and treatment guidelines. Unit costs were taken from the WHO-CHOICE (Choosing Interventions that are Cost-Effective) price database. MAIN OUTCOME MEASURES: Cost per disability adjusted life year (DALY) averted, expressed in international dollars ($Int) for the year 2005. RESULTS: Most of the interventions studied were considered highly cost effective, meaning they generate one healthy year of life at a cost of <$Int2000 (which is the gross domestic product per capita of the two regions considered here). Interventions that offer particularly good monetary value, and which could be considered for prioritised implementation or scale up, include demand reduction strategies of the Framework Convention for Tobacco Control (<$Int950 and <$Int200 per DALY averted in AfrE and SearD respectively); combination drug therapy for people with a >25% chance of experiencing a cardiovascular event over the next decade, either alone or together with specific multidrug regimens for the secondary prevention of post-acute ischaemic heart disease and stroke (<$Int150 and <$Int230 per DALY averted in AfrE and SearD respectively); and retinopathy screening and glycaemic control for patients with diabetes (<$Int2100 and <$Int950 per DALY averted in AfrE and SearD respectively). CONCLUSION: This comparative economic assessment has identified a set of population-wide and individual strategies for prevention and control of cardiovascular disease that are inexpensive and cost effective in low resource settings.

Total cardiovascular risk approach to improve efficiency of cardiovascular prevention in resource constrain settings.

OBJECTIVES: To determine the population distribution of cardiovascular risk in eight low- and middle-income countries and compare the cost of drug treatment based on cardiovascular risk (cardiovascular risk thresholds ≥ 30%/≥ 40%) with single risk factor cutoff levels. STUDY DESIGN AND SETTING: Using World Health Organization (WHO) and the International Society of Hypertension risk prediction charts, cardiovascular risk was categorized in a cross-sectional study of 8,625 randomly selected people aged 40-80 years (mean age, 54.6 years) from defined geographic regions of Nigeria, Iran, China, Pakistan, Georgia, Nepal, Cuba, and Sri Lanka. Cost estimates for drug therapy were calculated for three countries. RESULTS: A large fraction (90.0-98.9%) of the study population has a 10-year cardiovascular risk <20%. Only 0.2-4.8% are in the high-risk categories (≥ 30%). Adopting a total risk approach and WHO guidelines recommendations would restrict unnecessary drug treatment and reduce the drug costs significantly. CONCLUSION: Adopting a total cardiovascular risk approach instead of a single risk factor approach reduces health care expenditure by reducing drug costs. Therefore, limited resources can be more efficiently used to target high-risk people who will benefit the most. This strategy needs to be complemented with population-wide measures to shift the cardiovascular risk distribution of the whole population.