Honorio Silva

Prevalence of the Metabolic Syndrome in Latin America and its association with sub-clinical carotid atherosclerosis: the CARMELA cross sectional study

BackgroundMetabolic syndrome increases cardiovascular risk. Limited information on its prevalence in Latin America is available. The Cardiovascular Risk Factor Multiple Evaluation in Latin America (CARMELA) study included assessment of metabolic syndrome in 7 urban Latin American populations.MethodsCARMELA was a cross-sectional, population-based, observational study conducted in Barquisimeto, Venezuela; Bogota, Colombia; Buenos Aires, Argentina; Lima, Peru; Mexico City, Mexico; Quito, Ecuador; and Santiago, Chile. The prevalence of metabolic syndrome, defined according to the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III), and associated carotid atherosclerosis were investigated in 11,502 participants aged 25 to 64 years.ResultsAcross CARMELA cities, metabolic syndrome was most prevalent in Mexico City (27%) and Barquisimeto (26%), followed by Santiago (21%), Bogota (20%), Lima (18%), Buenos Aires (17%), and Quito (14%). In nondiabetic participants, prevalence was slightly lower but followed a comparable ranking. Overall, 59%, 59%, and 73% of women with high triglycerides, hypertension, or glucose abnormalities, respectively, and 64%, 48% and 71% of men with abdominal obesity, hypertension, or glucose abnormalities, respectively, had the full metabolic syndrome. Prevalence of metabolic syndrome increased with age, markedly so in women. Mean common carotid artery intima-media thickness (CCAIMT) and prevalence of carotid plaque increased steeply with increasing numbers of metabolic syndrome components; mean CCAIMT was higher and plaque more prevalent in participants with metabolic syndrome than without.ConclusionThe prevalence of metabolic syndrome and its components by NCEP ATP III criteria was substantial across cities, ranging from 14% to 27%. CARMELA findings, including evidence of the association of metabolic syndrome and carotid atherosclerosis, should inform appropriate clinical and public health interventions.

Dyslipidemia in seven Latin American cities: CARMELA study

OBJECTIVE The objective of this study was to describe the prevalence of dyslipidemia in the CARMELA study population. METHODS CARMELA was a cross-sectional study of cardiovascular risk conducted between September 2003 and August 2005 in adults (aged 25 to 64 years) living in Barquisimeto (n=1,824), Bogotá (n=1,511), Buenos Aires (n=1,412), Lima (n=1,628), Mexico City (n=1,677), Quito (n=1,620), and Santiago (n=1,605). Dyslipidemia was defined as the presence of one or more of the following conditions: triglycerides>/=200 mg/dL, or total cholesterol (TC)>/=240 mg/dL, or HDL cholesterol<40 mg/dL, or LDL cholesterol=not optimal, or currently taking antilipemic agents. RESULTS Prevalence rates of dyslipidemia in men and women were: 75.5% (CI: 71.9-79.1) and 48.7% (CI: 45.4-51.9) in Barquisimeto; 70% (CI: 66.2-73.8) and 47.7% (CI: 43.9-51.5) in Bogotá; 50.4% (CI: 46.8-54.0) and 24.1% (CI: 21.0-27.2) in Buenos Aires; 73.1% (CI: 69.3-76.8) and 62.8% (CI: 59.2-66.5) in Lima; 62.5% (CI: 58.5-66.5) and 37.5% (CI: 33.5-41.6) in Mexico City; 52.2% (CI: 47.9-56.5) and 38.1% (CI: 34.5-41.7) in Quito; and, 50.8% (CI: 47.1-54.4) and 32.8% (CI: 29.3-36.3) in Santiago. CONCLUSIONS Dyslipidemia was disturbingly prevalent and varied across cities. The most frequent dyslipidemia was low HDL-C followed by high triglycerides. The high TC/HDL-C ratios and non-HDL-C levels suggest a high risk of cardiovascular disease.

Hypertension in seven Latin American cities: the Cardiovascular Risk Factor Multiple Evaluation in Latin America (CARMELA) study.

Background Little information is available regarding hypertension, treatment, and control in urban population of Latin America. Objective We aimed to compare blood pressure (BP) distribution, hypertension prevalence, treatment, and control in seven Latin American cities following standard methodology. Methods The Cardiovascular Risk Factor Multiple Evaluation in Latin America (CARMELA) study was a cross-sectional, epidemiologic study assessing cardiovascular risk factors using stratified multistage sampling of adult populations (aged 25–64 years) in seven cities: Barquisimeto (Venezuela; n = 1848); Bogotá (n = 1553); Buenos Aires (n = 1482); Lima (n = 1652); Mexico City (n = 1720); Quito (n = 1638); and Santiago (n = 1655). The prevalence of hypertension and high normal BP were determined based on 2007 European Society of Hypertension and European Society of Cardiology definitions. Results BP increased with age in men and women; pulse pressure increased mainly in the upper age group. The hypertension prevalence ranged from 9% in Quito to 29% in Buenos Aires. One-quarter to one-half of the hypertension cases were previously undiagnosed (24% in Mexico City to 47% in Lima); uncontrolled hypertension ranged from 12% (Lima) to 41% (Mexico City). High normal BP was also evident in a substantial number of each city participants (≈5–15%). Majority of population has other cardiovascular risk factors despite hypertension; only 9.19% of participants have no risk factors apart from hypertension. Conclusion From 13.4 to 44.2% of the populations of seven major Latin American cities were hypertensive or had high normal BP values. Most hypertensive patients have additional risk factors. Public health programs need to target prevention, detection, treatment, and control of total cardiovascular risk in Latin America.

Common Carotid Artery Intima-Media Thickness: The Cardiovascular Risk Factor Multiple Evaluation in Latin America (CARMELA) Study Results

Background: Measurement of far wall common carotid artery intima-media thickness (CCAIMT) has emerged as a predictor of incident cardiovascular events. The Cardiovascular Risk Factor Multiple Evaluation in Latin America (CARMELA) study was the first large-scale population-based assessment of both CCAIMT and cardiovascular risk factor prevalence in 7 Latin American cities; the relationship between CCAIMT and cardiovascular risk markers was assessed in these urban Latin American centers. Methods: CARMELA was across-sectional, population-based, observational study using stratified, multistage sampling. The participants completed a questionnaire, were evaluated in a clinical visit and underwent carotid ultrasonography. Clinical measurements were obtained by health personnel trained, certified and supervised by CARMELA investigators. Mannheim intima-media thickness consensus guidelines were followed for measurement of CCAIMT. Results: In all cities and for both sexes, CCAIMT increased with higher age. CCAIMT was greater in the presence of cardiovascular risk factors than in their absence. In all cities, there was a statistically significant linear trend between increasing CCAIMT and a growing number of cardiovascular risk factors (p < 0.001). After adjustment for age and sex, metabolic syndrome was strongly associated with increased CCAIMT (p < 0.001 in all cities), as were hypercholesterolemia, obesity and diabetes (p < 0.001 in most cities). By multivariate analysis, hypertension was independently associated with an increase in CCAIMT in all cities (p < 0.01). Conclusions: CARMELA was the first large-scale population study to provide normal CCAIMT values according to age and sex in urban Latin American populations and to show CCAIMT increases in the presence of cardiovascular risk factors and metabolic syndrome.

Cardiovascular Risk Awareness, Treatment, and Control in Urban Latin America

Effective prevention and treatment of cardiovascular diseases require regular screening for risk factors, high awareness of the condition, effective treatment of the identified risk factors, and adherence to the prescribed treatment. The Cardiovascular Risk Factor Multiple Evaluation in Latin America study was a cross-sectional, population-based, observational study of major cardiovascular risk factors-including hypertension, diabetes, and hypercholesterolemia-in 7 Latin American cities. This report presents data on assessment, diagnosis, extent, and effectiveness of treatment, adherence to treatment, and reasons for nonadherence. Data were collected through household questionnaire-based interviews administered to 5383 men and 6167 women, 25-64 years of age, living in the following cities: Barquisimeto, Venezuela; Bogota, Colombia; Buenos Aires, Argentina; Lima, Peru; Mexico City, Mexico; Quito, Ecuador; and Santiago, Chile. Participants also completed a clinic visit for anthromorphometric and laboratory assessments. Rates of prior diagnosis of hypertension and diabetes were high (64% and 78% of affected individuals, respectively) but relatively low for hypercholesterolemia (41%). The majority of affected individuals (hypercholesterolemia 88%, diabetes 67%, and hypertension 53%) were untreated. Among individuals who were receiving pharmacologic treatment, targets for control of hypertension, diabetes, and hypercholesterolemia were achieved by 51%, 16%, and 52%, respectively. Adherence to treatment was observed in 69% of individuals with hypertension, 63% with diabetes, and 66% with hypercholesterolemia. Forgetfulness was the major cause of nonadherence for all 3 conditions. There is a substantial need for increasing patient education, diagnosis, treatment, adherence, and control of cardiovascular risk factors in the 7 Latin American cities.

Effect of prazosin on blood lipids and on thyroid function in hypertensive patients.

Nineteen patients with essential hypertension (EH) were studied as outpatients. After administration of chlorthalidone, 50 mg/day for 4 weeks, prazosin 1–4 mg/day (1.82 ± 0.33 nig/day) was added for a period of 12 weeks. Prazosin lowered supine blood pressure from 149.7 ± 2.85/102.0 ± 2.75 mm Hg to 128.2 ± 3.0/86.1 ± 1.04 mm Hg (p <0.001). Prazosin did not alter heart rate significantly. Prazosin increased the thyroid stimulating hormone (TSH) from 3.63 ± 0.33 μU/ml to 4.83 ± 0.45 μU/ml (p < 0.025). thyroxine (T4) from 10.03 ± 0.29 μg/ml to 10.85 ± 0.42 p.g/ml (p < 0.005). and decreased triiodothyronine (T4) from 36.65 ± 0.62% to 35.42 ± 0.56%, which was not significant. The free thyroxine index (FTI) increased slightly from 3.67 ± 0.12 to 3.83 ± 0.14 (p < 0.025). However, all values remained within the normal range for the laboratory. Serum cholesterol increased insignificantly. Triglycerides decreased significantly from 223.4 ± 50.6 mg/mg/dl to161.7 ± 29.0mg/dl(p < 0.05). Highdensity lipoproteins(HDL)increascdsignificantly from30.1 ± 2.1% 36.0 ± 3.06 (p < 0.025). Low density lipoproteins (LDL) decreased insignificantly and very low density lipoproteins (VLDL) decreased from 20.9 ± 3.44 to 16.3 ± 2.85 (p < 0.005). The cholesterol ratio increased from 45.51 ± 4.3 to 64.71 ± 10.7 ( +42.1%). These results indicate that, in patients with essential hypertension. prazosin is an effective antihypertensive agent and that it significantly increases HDL. decreases VLDL. and improves the cholesterol ratio

HDL-C, triglycerides and carotid IMT: A meta-analysis of 21,000 patients with automated edge detection IMT measurement☆

OBJECTIVE Common carotid artery (CCA) intima-media thickness (IMT), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C), but not triglyceride levels, are markers of future cardiovascular events. The relationship between these three factors is, however, unclear. METHODS We included six large observational studies that used the same harmonized, B-mode ultrasound protocol, the same software for IMT measurement by automatic edge detection on CCA in a plaque-free region, following the Mannheim consensus, and certification of all sonographers. Using the best view of the CCA, the sonographer had to confirm that the quality index was ≥ 0.5 on a measurement performed on 10-mm length. We used individual data meta-analysis to estimate the cross-sectional associations of lipids with CCA-IMT. RESULTS Overall, 21,587 patients with complete information on lipids and CCA-IMT were available. Age- and sex-adjusted CCA-IMT differed by -7.8 μm (95% CI -9.1 to -6.5 μm, P < 0.001) per 1 SD higher HDL-C level. After further adjustment for other atherosclerosis risk factors, the relationship was attenuated, but remained significant (regression coefficient, -3.7 μm; P < 0.001). This was found regardless of LDL-C levels (P for heterogeneity = 0.70). After adjustment for age and sex, triglycerides were positively associated with CCA-IMT, overall and in each LDL-C subgroup, but not after further adjustments for other risk factors. CONCLUSIONS Relationships between HDL-C and triglyceride levels and CCA-IMT were consistent with that previously observed with clinical events by the Emergency Risk Collaboration group, including at low LDL-C levels. This reinforces the need to verify whether raising HDL-C levels decreases both CCA-IMT and future clinical events.

Effects of prazosin and alphamethyldopa on blood lipids and lipoproteins in hypertensive patients

SummaryThe effects of prazosin and alphamethyldopa on blood lipids and lipoproteins were assessed in 20 patients with mild or moderate arterial hypertension. Parameters measured included serum cholesterol (CHO), triglycerides (TG), high density lipoprotein-cholesterol (HDL-CHO), insulin (I), glucose (G), and non-esterified fatty acids (NEFA). Prazosin — 4 mg/day for 6 weeks in hydrochlorothiazide-treated patients lowered blood pressure by 18.6/17.2 (systolic/diastolic pressure) mmHg. There was a significant decrease in CHO (−5.8%), in I (−16.5%), and in NEFA (−3.0%), and a significant increase in HDL-CHO (+15.5%). Alphamethyldopa 250–750 mg/day for 6 weeks in hydrochlorothiazide-treated patients lowered blood pressure by 18.8/14.6 (systolic/diastolic pressure) mmHg, accompanied by a non-significant decrease in CHO and TG, and significant increases in HDL-CHO (+10.3%), G (+8.5%) and NEFA (+6.4%). Thus, prazosin appears to have a more beneficial effect on blood lipids and lipoproteins than alphamethyldopa.

Doxazosin in the treatment of essential hypertension in general medical practice in Latin America

This Latin American study assessed in the general practice setting the efficacy and tolerance of once-daily doxazosin in the treatment of mild or moderate essential hypertension (sitting diastolic blood pressure, 95 to 115 mm Hg). Patients (n = 220) were treated with doxazosin for 12 weeks as monotherapy or in combination with other antihypertensive agents. At the final visit, doxazosin produced a mean change in sitting systolic/diastolic blood pressure of -18.4/-14.4 mm Hg, at a mean daily dose of 4.3 mg. One hundred sixty-three (77.6%) of the 210 evaluable patients were considered a therapeutic success. Lipid analyses identified a statistically significant (p = 0.02) reduction in total serum cholesterol (4.85%) and an overall decrease in triglyceride levels (5.12%). According to the Framingham Heart Study equation, doxazosin produced a highly significant (p less than 0.001) 20% reduction in the calculated probability of developing coronary heart disease in 10 years. Of the 220 patients evaluated, 54 (24.5%) reported side effects that were considered related to treatment. Ten (4.5%) patients reported side effects unrelated to treatment and 37 (16.8%) reported events of unknown relationship. Most side effects were mild or moderate and were tolerated or disappeared with continued treatment. Nine patients (4.1%) were discontinued from therapy and in 13 (5.9%) the dose was reduced. The most prevalent side effects were headache and dizziness. The investigators overall assessment of antihypertensive efficacy was excellent or good for 176 patients (80.4%); tolerance was considered excellent or good in 193 patients (88.5%).(ABSTRACT TRUNCATED AT 250 WORDS)

Haemodynamic effects of enalapril, a new converting enzyme inhibitor, in hypertensive patients

SummaryThe haemodynamic effects of enalapril (EN), a new, long-acting, nonsulphhydryl converting enzyme inhibitor, were evaluated by non-invasive methods in 10 adult patients with mild to moderate essential hypertension (EH). Patients were randomly assigned, double blind to 2 treatment groups (EN 20 mg o.d. or 10 mg b.d.) for 4 weeks, and were crossed over to the other dosage regimen after a 2-week washout period. Measurements included mean arterial pressure (MAP), heart rate (HR), cardiac output (CO), limb blood flow (LBF), plasma aldosterone (ALD), plasma renin activity (PRA) and systolic time intervals (STI). Both regimens (b.d. and o.d.) significantly reduced MAP (15.3% and 16.3%, respectively), total peripheral resistance (20.3% and 21.8%, respectively), limb vascular resistance (24.1% and 24.9%) and ALD (33.5% and 36.9%) and increased CO (7.8% and 8.7%), LBF (10.9% and 11.6%) and PRA (10.4% and 9.5%). No significant change was observed in HR or STI. EN 20 mg o.d. or 10 mg b.d. reduced arterial pressure to a similar extent through a fall in total peripheral resistance. An increase in CO was also observed.