Rosalba Rojas-Martínez

A novel risk score to predict cardiovascular disease risk in national populations (Globorisk): a pooled analysis of prospective cohorts and health examination surveys

BACKGROUND Treatment of cardiovascular risk factors based on disease risk depends on valid risk prediction equations. We aimed to develop, and apply in example countries, a risk prediction equation for cardiovascular disease (consisting here of coronary heart disease and stroke) that can be recalibrated and updated for application in different countries with routinely available information. METHODS We used data from eight prospective cohort studies to estimate coefficients of the risk equation with proportional hazard regressions. The risk prediction equation included smoking, blood pressure, diabetes, and total cholesterol, and allowed the effects of sex and age on cardiovascular disease to vary between cohorts or countries. We developed risk equations for fatal cardiovascular disease and for fatal plus non-fatal cardiovascular disease. We validated the risk equations internally and also using data from three cohorts that were not used to create the equations. We then used the risk prediction equation and data from recent (2006 or later) national health surveys to estimate the proportion of the population at different levels of cardiovascular disease risk in 11 countries from different world regions (China, Czech Republic, Denmark, England, Iran, Japan, Malawi, Mexico, South Korea, Spain, and USA). FINDINGS The risk score discriminated well in internal and external validations, with C statistics generally 70% or more. At any age and risk factor level, the estimated 10 year fatal cardiovascular disease risk varied substantially between countries. The prevalence of people at high risk of fatal cardiovascular disease was lowest in South Korea, Spain, and Denmark, where only 5-10% of men and women had more than a 10% risk, and 62-77% of men and 79-82% of women had less than a 3% risk. Conversely, the proportion of people at high risk of fatal cardiovascular disease was largest in China and Mexico. In China, 33% of men and 28% of women had a 10-year risk of fatal cardiovascular disease of 10% or more, whereas in Mexico, the prevalence of this high risk was 16% for men and 11% for women. The prevalence of less than a 3% risk was 37% for men and 42% for women in China, and 55% for men and 69% for women in Mexico. INTERPRETATION We developed a cardiovascular disease risk equation that can be recalibrated for application in different countries with routinely available information. The estimated percentage of people at high risk of fatal cardiovascular disease was higher in low-income and middle-income countries than in high-income countries. FUNDING US National Institutes of Health, UK Medical Research Council, Wellcome Trust.

Estimated incidence of cardiovascular complications related to type 2 diabetes in Mexico using the UKPDS outcome model and a population-based survey

BackgroundTo estimate the incidence of complications, life expectancy and diabetes related mortality in the Mexican diabetic population over the next two decades using data from a nation-wide, population based survey and the United Kingdom Prospective Diabetes Study (UKPDS) outcome modelMethodsThe cohort included all patients with type 2 diabetes evaluated during the National Health and Nutrition Survey (ENSANut) 2006. ENSANut is a probabilistic multistage stratified survey whose aim was to measure the prevalence of chronic diseases. A total of 47,152 households were visited. Results are shown stratified by gender, time since diagnosis (> or ≤ to 10 years) and age at the time of diagnosis (> or ≤ 40 years).ResultsThe prevalence of diabetes in our cohort was 14.4%. The predicted 20 year-incidence for chronic complications per 1000 individuals are: ischemic heart disease 112, myocardial infarction 260, heart failure 113, stroke 101, and amputation 62. Furthermore, 539 per 1000 patients will have a diabetes-related premature death. The average life expectancy for the diabetic population is 10.9 years (95%CI 10.7-11.2); this decreases to 8.3 years after adjusting for quality of life (CI95% 8.1-8.5). Male sex and cases diagnosed after age 40 have the highest risk for developing at least one major complication during the next 20 years.ConclusionsBased on the current clinical profile of Mexican patients with diabetes, the burden of disease related complications will be tremendous over the next two decades.

Perfil del comportamiento sexual en adolescentes mexicanos de 12 a 19 años de edad: resultados de la ENSA 2000

Objective. To describe traits associated with sexual behaviors in Mexican adolescents, their knowledge about contraception, and factors associated with pregnancy and utilization of contraceptives during first sexual intercourse. Material and Methods. Data from the Mexican National Health Survey 2000 (ENSA 2000) were analyzed. This study, conducted between September 1999 and March 2000, was a complex survey with a probabilistic, stratified, and cluster sampling design. The sample population included 15 241 adolescents 12 to 19 years of age. Data analysis included descriptive statistics and a chi-squared test for differences of proportions; also, logistic regression was used to obtain odds ratios. Results. A total of 69.2% adolescents reported knowledge of at least one contraception method; 16.4% of subjects reported having had sexual intercourse. Males initiated sexual intercourse earlier than females and only 37% of all adolescents utilized contraceptives during their first sexual intercourse. Logistic regression analysis showed that being male, having a higher education, having knowledge of at least one contraception method, and having initiated sexual intercourse at an older age, were factors associated with utilization of a contraception method in their first sexual intercourse. A total of 55.7% of sexually active female adolescents had been pregnant. Pregnancy among adolescents was associated with low educational level, sexual activity at early age, and to have sometime lived in free union. Conclusions. The majority of sexually active adolescents did not use contraception during their first sexual intercourse, rendering them at risk of unwanted pregnancies.

Prevalence of obesity and metabolic syndrome components in Mexican adults without type 2 diabetes or hypertension

OBJECTIVE To describe the number of Mexican adults with undiagnosed diabetes and arterial hypertension and their association with obesity. MATERIAL AND METHODS The study included a sub-sample of 6 613 subjects aged 20 years or more who participated in the 2006 National Health and Nutrition Survey (ENSANUT 2006). Subjects with a previous diagnosis of diabetes or hypertension (n=1 861) were excluded. Prevalences and standard errors were estimated, taking into account the complex sample design. RESULTS 6.4 million adults have obesity and undiagnosed impaired fasting glucose. Almost two million more have fasting glucose levels diagnostic for diabetes. As for arterial blood pressure, 5.4 million adults had prehypertension. Another 5.4 million adults had blood pressure levels suggestive of probable hypertension. A total of 21.4 million Mexican adults with obesity had at least one further component of the metabolic syndrome. CONCLUSIONS A large proportion of adults with obesity-related metabolic comorbidities remains undiagnosed in Mexico.

Hypoalphalipoproteinemia in populations of Native American ancestry: an opportunity to assess the interaction of genes and the environment.

Purpose of this review Our aim is to review the environmental and genetic factors associated with hypoalphalipoproteinemia in populations of Native American ancestry. We examine the strength of the association and outline the population-specific genetic factors that lead to a higher susceptibilty for this condition. Recent findings Low HDL is the most common lipid abnormality in populations of Native American ancestry. Population-based surveys carried out in Latin America and in Mexican Americans shows that 40–60% of adults have hypoalphalipoproteinemia. The contribution of this trait to the metabolic syndrome is greater in individuals with Native American ancestry than in other ethnic groups. Several environmental factors have contributed to this phenomenon (i.e. high dietary content of carbohydrates and fat due to cultural factors and a growing incidence of obesity). In addition, results from recent genetic studies show that certain hypoalphalipoproteinemia susceptibility alleles are ethnic specific for Native Americans. The variant R230C of the ATP-binding cassette transporter subfamily A member 1 gene (ABC-A1) is common among mestizos (10.9% in Mexican mestizos) and its presence has a significant negative effect on HDL cholesterol levels (−4.2%). An additional noteworthy finding is that the R230C variant appears to be specific for the Amerindian populations. Its allele frequency is 0.28 in Mayans, 0.214 in Purepechas, 0.203 in Yaquis and 0.179 among Teenek. In contrast, the C230 allele has not been found in African, European, Chinese or South Asian populations. Summary The assessment of the genetic and environmental determinants of hypoalphalipoproteinemia in populations of Native American origin provides an opportunity to assess the population-specific interactions between genes and the environment

Burden of type 2 diabetes in Mexico: past, current and future prevalence and incidence rates

INTRODUCTION Mexico diabetes prevalence has increased dramatically in recent years. However, no national incidence estimates exist, hampering the assessment of diabetes trends and precluding the development of burden of disease analyses to inform public health policy decision-making. Here we provide evidence regarding current magnitude of diabetes in Mexico and its future trends. METHODS We used data from the Mexico National Health and Nutrition Survey, and age-period-cohort models to estimate prevalence and incidence of self-reported diagnosed diabetes by age, sex, calendar-year (1960-2012), and birth-cohort (1920-1980). We project future rates under three alternative incidence scenarios using demographic projections of the Mexican population from 2010-2050 and a Multi-cohort Diabetes Markov Model. RESULTS Adult (ages 20+) diagnosed diabetes prevalence in Mexico increased from 7% to 8.9% from 2006 to 2012. Diabetes prevalence increases with age, peaking around ages 65-68 to then decrease. Age-specific incidence follows similar patterns, but peaks around ages 57-59. We estimate that diagnosed diabetes incidence increased exponentially during 1960-2012, roughly doubling every 10 years. Projected rates under three age-specific incidence scenarios suggest diabetes prevalence among adults (ages 20+) may reach 13.7-22.5% by 2050, affecting 15-25 million individuals, with a lifetime risk of 1 in 3 to 1 in 2. CONCLUSIONS Diabetes prevalence in Mexico will continue to increase even if current incidence rates remain unchanged. Continued implementation of policies to reduce obesity rates, increase physical activity, and improve population diet, in tandem with diabetes surveillance and other risk control measures is paramount to substantially reduce the burden of diabetes in Mexico.

Optimal cutoff points for the detection of undiagnosed type 2 diabetes, hypertension and metabolic syndrome in Mexican adults

OBJECTIVE To compare the waist circumference cutoff points established by the American Heart Association and the National Heart, Lung and Blood Institute (AHA/NHLBI) with those of the International Diabetes Federation (IDF) for the screening of diabetes, hypertension, and metabolic syndrome in Mexican adults. MATERIAL AND METHODS This study comprised a subsample of the ENSANUT 2006. Subjects without diabetes and hypertension and non-pregnant women were included. Sensitivity, specificity, and predictive values were compared using AUC and the positive likelihood ratio test [LR(+)]. RESULTS In subjects aged ≥40 years, sensitivity for detection of diabetes and hypertension was higher for the IDF thresholds (85.34 and 86.87%, respectively) compared with those of the AHA/NHLBI (59.49 and 52.41%, respectively). LR(+) were higher for IDF thresholds compared with AHA/NHLBI. Similar results in subjects aged ≥65 years were observed. CONCLUSIONS The measurement of abdominal obesity defined by the IDF was a better screening tool for diabetes and hypertension, considering that initially a high sensitivity and low cost tool at population level is required.

Laboratory-based and office-based risk scores and charts to predict 10-year risk of cardiovascular disease in 182 countries: a pooled analysis of prospective cohorts and health surveys.

BACKGROUND Worldwide implementation of risk-based cardiovascular disease (CVD) prevention requires risk prediction tools that are contemporarily recalibrated for the target country and can be used where laboratory measurements are unavailable. We present two cardiovascular risk scores, with and without laboratory-based measurements, and the corresponding risk charts for 182 countries to predict 10-year risk of fatal and non-fatal CVD in adults aged 40-74 years. METHODS Based on our previous laboratory-based prediction model (Globorisk), we used data from eight prospective studies to estimate coefficients of the risk equations using proportional hazard regressions. The laboratory-based risk score included age, sex, smoking, blood pressure, diabetes, and total cholesterol; in the non-laboratory (office-based) risk score, we replaced diabetes and total cholesterol with BMI. We recalibrated risk scores for each sex and age group in each country using country-specific mean risk factor levels and CVD rates. We used recalibrated risk scores and data from national surveys (using data from adults aged 40-64 years) to estimate the proportion of the population at different levels of CVD risk for ten countries from different world regions as examples of the information the risk scores provide; we applied a risk threshold for high risk of at least 10% for high-income countries (HICs) and at least 20% for low-income and middle-income countries (LMICs) on the basis of national and international guidelines for CVD prevention. We estimated the proportion of men and women who were similarly categorised as high risk or low risk by the two risk scores. FINDINGS Predicted risks for the same risk factor profile were generally lower in HICs than in LMICs, with the highest risks in countries in central and southeast Asia and eastern Europe, including China and Russia. In HICs, the proportion of people aged 40-64 years at high risk of CVD ranged from 1% for South Korean women to 42% for Czech men (using a ≥10% risk threshold), and in low-income countries ranged from 2% in Uganda (men and women) to 13% in Iranian men (using a ≥20% risk threshold). More than 80% of adults were similarly classified as low or high risk by the laboratory-based and office-based risk scores. However, the office-based model substantially underestimated the risk among patients with diabetes. INTERPRETATION Our risk charts provide risk assessment tools that are recalibrated for each country and make the estimation of CVD risk possible without using laboratory-based measurements. FUNDING National Institutes of Health.

Expected population weight and diabetes impact of the 1-peso-per-litre tax to sugar sweetened beverages in Mexico

Study question What effect on body mass index, obesity and diabetes can we expect from the 1-peso-per-litre tax to sugar sweetened beverages in Mexico? Methods Using recently published estimates of the reductions in beverage purchases due to the tax, we modelled its expected long-term impacts on body mass index (BMI), obesity and diabetes. Microsimulations based on a nationally representative dataset were used to estimate the impact of the tax on BMI and obesity. A Markov population model, built upon an age-period-cohort model of diabetes incidence, was used to estimate the impact on diagnosed diabetes in Mexico. To analyse the potential of tax increases we also modelled a 2-peso-per-litre tax scenario. Study answer and limitations Ten years after the implementation of the tax, we expect an average reduction of 0.15 kg/m2 per person, which translates into a 2.54% reduction in obesity prevalence. People in the lowest level of socioeconomic status and those between 20 and 35 years of age showed the largest reductions in BMI and overweight and obesity prevalence. Simulations show that by 2030, under the current implementation of 1-peso-per-litre, the tax would prevent 86 to 134 thousand cases of diabetes. Overall, the 2-peso-per-litre scenario is expected to produce twice as much of a reduction. These estimates assume the tax effect on consumption remains stable over time. Sensitivity analyses were conducted to assess the robustness of findings; similar results were obtained with various parameter assumptions and alternative modelling approaches. What this study adds The sugar-sweetened beverages tax in Mexico is expected to produce sizable and sustained reductions in obesity and diabetes. Increasing the tax could produce larger benefits. While encouraging, estimates will need to be updated once data on direct changes in consumption becomes available.

Epidemiology of diabetes mellitus in Mexico

Type 2 diabetes is the main health problem in Mexico. The large and growing number of cases and the remarkable economic impact of the disease support this statement. The condition is expressed at an earlier age and at a lower body mass index in Mexican mestizos compared with the age and body mass index reported in Caucasians. In addition, Mexican mestizos have an increased susceptibility to developing diabetic nephropathy. The Mexican health system needs major adjustments in order to prevent and treat type 2 diabetes. Treatment is not currently based on the needs and expectations of the patient. As a result, it is insufficient, belated, and costly. Close to 20% of the preventable deaths in Mexico are caused by diabetes and related metabolic diseases. Even a small decrease in this rate could result in substantial savings for the Mexican healthcare system.