The socio-colonial history of Surinamese surnames applied to a validated surname list to identify ancestry in health research.

Around half of the population of Suriname, who are mainly of African and South Asian descent, migrated to the Netherlands at the end of the previous century, where they face higher perinatal and maternal mortality and up to 5 years lower life expectancy than European-Dutch. Analyses by ancestry are needed to address these inequalities, but the law prohibits registration by ancestry. Therefore, a list of Surinamese surnames was compiled and validated to identify the largest groups, African-Surinamese or South Asian-Surinamese ancestry in health research. A complete database of Surinamese surnames was provided by the National Population Registry of Suriname. Surname recognition by researchers of Surinamese ancestry was used. Disagreement was resolved using historical registers and through discussion. The list was further validated against contemporary lists of Surinamese surnames with self-defined ancestry, obtained during population and clinical studies in Suriname and the Netherlands. All 71,529 Surinamese surnames were encoded, as African-Surinamese (34%), South Asian-Surinamese (18%), Brazilian or other Iberian (17%), Indonesian-Surinamese (13%), Chinese-Surinamese (5%), First Nation (2%), and other (10%). Compared to self-defined ancestry, South Asian-Surinamese surname coding had 100% sensitivity, 99.8% specificity, and 99.9% accuracy. For African-Surinamese, who may have Dutch surnames, these values depended on geocoding. With a known Surinamese origin, sensitivity, specificity, and accuracy were, respectively, 97.3%, 100%, and 98.6%, but without this information, there was interference of African-Surinamese with European-Dutch surnames in the Dutch validation sample. In conclusion, the Surinamese Surname List has a high accuracy in identifying persons of Surinamese ancestry. This quick, inexpensive, and nonintrusive method, which is unaffected by response bias, might be a valuable tool in public health research to help address the profound health disparities by ancestry.

Aortic pulse wave velocity in individuals of Asian and African ancestry: the HELISUR study.

Aortic pulse wave velocity has emerged as an important predictor of cardiovascular events, but data on ethnic differences in pulse wave velocity remain scarce. We explored differences in pulse wave velocity between people of Asian and African ancestry. Data were used from the cross-sectional Healthy Life in Suriname (HELISUR) study. Pulse wave velocity was estimated oscillometrically with the Arteriograph. We included 353 Asians and 364 Africans, aged respectively 44.9 (SD 13.5) and 42.8 (SD 14.1) years (p = 0.05). Crude median PWV was higher in Asians than in Africans (8.1 [IQR 6.9-10.1] m/s vs. 7.7 [IQR 6.5-9.3] m/s, p = 0.03), which was mainly attributable to an increased PWV in Asians ≥ 50 years (10.1 [IQR 8.7-11.8] m/s vs. 9.1 [IQR 7.9-11.3] m/s in Africans ≥50 years, p < 0.01). After adjustment for age and MAP in multivariable linear regression, Asians had a 1.044 [95% CI 1.019-1.072] m/s higher PWV compared to Africans. Additional adjustment for sex, glucose, total cholesterol, HDL cholesterol, triglycerides, BMI, and waist circumference did not substantially change the difference in pulse wave velocity between Asians and Africans (+1.044 [95% CI 1.016-1.074] m/s for Asians vs. Africans). In conclusion, persons of Asian ancestry have a higher pulse wave velocity than those of African ancestry. This persisted after adjustment for important cardiovascular risk parameters, including age and blood pressure. The higher PWV found in Asians could be consistent with their increased coronary heart disease risk.

Chronic kidney disease and kidney health care status: the healthy life in Suriname (HeliSur) study.

The high cardiovascular risk burden in low- and middle-income countries is expected to lead to an explosive increase in chronic kidney disease (CKD). However, population data on CKD from these countries are scarce. Therefore, we assessed kidney health in Suriname. In the Healthy Life in Suriname (HeliSur) study, a random sample of the adult population, we collected data with standardized questionnaires, physical examination, and blood and urine samples analysed in a central laboratory. Prevalent CKD was graded with KDIGO guidelines. In addition, we assessed national data on prevalent renal replacement therapy (RRT), estimated the future need for RRT, and evaluated national kidney health work force and policies. We include 1117 participants (2.0‰ of the population), 63% women, 40% of African ancestry and 43% of Asian ancestry, with a mean age of 42.2 (SE 0.4) years. Blood pressure is elevated in 72% of the participants, 26% have diabetes or prediabetes, and 78% are obese or overweight. The prevalence of CKD is 5.4%, and around 0.3% have kidney failure, translating to approximately 1500 patients nationally (2690 per million population, pmp), with currently 516 patients (920 pmp) on dialysis. Based on the participants from the random population sample in CKD stage G3 or G4, we estimate that 6750-10,750 pmp may develop kidney failure within the next 10 years. However, specialized kidney health workforce is currently very limited, and specific national or local policies for CKD management are lacking. Since the large majority of the general population has one or more risk factors for CKD including elevated blood pressure, urgent action is needed to strengthen kidney health care and prevent a catastrophic rise in need for RRT in the coming years.

Hypertension and Cardiovascular Risk Profile in a Middle-Income Setting: The HELISUR Study.

BACKGROUND: Hypertension is the leading risk factor responsible for premature death worldwide, but its burden has shifted to low- and middle-income countries. Therefore, we studied hypertension and cardiovascular risk in the population of Suriname, a middle-income country with a predominantly urban population of African and Asian ancestry. METHODS: A random sample of 1,800 noninstitutionalized men and women aged 18-70 years was selected to be interviewed at home and examined at the local hospital for cardiovascular risk factors, asymptomatic organ damage, and cardiovascular disease. RESULTS: The 1,157 participants examined (37% men) were mainly of self-defined Asian (43%) or African (39%) ancestry, mean age 43 years (SD 14). The majority of the population (71%) had hypertension or prehypertension, respectively, 40% and 31%. Furthermore, 72% was obese or overweight, while 63% had diabetes or prediabetes. Only 1% of the adult population had an optimal cardiovascular risk profile. Hypertension awareness, treatment, and control were respectively 68%, 56%, and 20%. In line with this, 22% of the adult population had asymptomatic organ damage, including increased arterial stiffness, left ventricular hypertrophy, microalbuminuria, or asymptomatic chronic kidney disease. CONCLUSIONS: In this first extensive cardiovascular assessment in the general population of this middle-income Caribbean country, high prevalence of hypertension with inadequate levels of treatment and control was predominant. The findings emphasize the need for collaborative effort from national and international bodies to prioritize the implementation of affordable and sustainable public health programs that combat the escalating hypertension and cardiovascular risk factor burden.

Assessing the feasibility of the Healthy Life in Suriname Study: using advanced hemodynamics to evaluate cardiovascular risk.

OBJECTIVES: To determine the feasibility of assessing population cardiovascular risk with advanced hemodynamics in the Healthy Life in Suriname (HELISUR) study. METHODS: This was a preliminary study conducted in May - June 2012 using the Technical-Economic-Legal-Operational-Scheduling (TELOS) method to assess the feasibility of the HELISUR-a large-scale, cross-sectional population study of cardiovascular risk factors and disease in Suriname. Suriname, a middle-income country in South America with a population of mostly African and Asian ethnicity, has a high risk of cardiovascular disease. A total of 135 volunteers 18 - 70 years of age participated. A health questionnaire was tested in a primary health care center, and non-invasive cardiovascular evaluations were performed in an academic health center. The cardiovascular evaluation included sitting, supine, and standing blood pressure, and intermediate endpoints, such as cardiac output, peripheral vascular resistance, pulse wave velocity, and augmentation index. RESULTS: The TELOS testing found that communicating by cellular phone was most effective for appointment adherence, and that completion of the questionnaire often required assistance from a trained interviewer; modifications to improve the clarity of the questions are recommended. Regarding the extended cardiovascular assessments of peripheral and central hemodynamics, the findings showed these to be technically and operationally feasible and well tolerated by participants, in terms of burden and duration. CONCLUSIONS: Findings of this feasibility assessment indicate that large-scale, detailed evaluations of cardiovascular risk, including a questionnaire and advanced central and peripheral hemodynamics, are feasible in a high-risk population in a middle-income setting.

Health literacy in Suriname.

BACKGROUND: Low health literacy is an independent predictor of cardiovascular mortality. However, data on health literacy in low- and middle-income countries are scarce. Therefore, we assessed the level of health literacy in Suriname, a middle-income country with a high cardiovascular mortality. METHODS: We estimated health literacy in a convenience sample at an urban outpatient center in the capital and at a semirural health center, using the validated Rapid Estimate of Adult Literacy in Medicine adapted for the Dutch language (REALM-D) instrument. REALM-D scores vary from 0 to 66 (all correct). The primary outcome was the level of health literacy. Furthermore, we assessed the effect of age, sex, ethnicity, disease history, research location, and level of education on health literacy with multivariable linear regression. RESULTS: We included 99 volunteers (52% men; 51% urban research location) with a mean age of 44.9 years (SD 13.4). The mean REALM-D score was moderate: 48.6 (SD 8.1). Greater health literacy was associated with male sex, an urban research location, and a higher educational level. CONCLUSION: Health literacy was moderate in these Surinamese participants. Health care workers should take health literacy into account, and targeted interventions should be developed to improve health literacy in Suriname.

Assessing the feasibility of the Healthy Life in Suriname Study: using advanced hemodynamics to evaluate cardiovascular risk / Evaluación de la factibilidad del estudio Vida Sana en Suriname: uso de hemodinámica avanzada para evaluar el riesgo de enfermedades cardiovasculares / Avaliação da viabilidade do Estudo de Vida Saudável no Suriname: uso de hemodinâmica avançada para avaliar o risco cardiovascular

ABSTRACT Objectives To determine the feasibility of assessing population cardiovascular risk with advanced hemodynamics in the Healthy Life in Suriname (HELISUR) study. Methods This was a preliminary study conducted in May – June 2012 using the Technical-Economic-Legal-Operational-Scheduling (TELOS) method to assess the feasibility of the HELISUR—a large-scale, cross-sectional population study of cardiovascular risk factors and disease in Suriname. Suriname, a middle-income country in South America with a population of mostly African and Asian ethnicity, has a high risk of cardiovascular disease. A total of 135 volunteers 18 – 70 years of age participated. A health questionnaire was tested in a primary health care center, and non-invasive cardiovascular evaluations were performed in an academic health center. The cardiovascular evaluation included sitting, supine, and standing blood pressure, and intermediate endpoints, such as cardiac output, peripheral vascular resistance, pulse wave velocity, and augmentation index. Results The TELOS testing found that communicating by cellular phone was most effective for appointment adherence, and that completion of the questionnaire often required assistance from a trained interviewer; modifications to improve the clarity of the questions are recommended. Regarding the extended cardiovascular assessments of peripheral and central hemodynamics, the findings showed these to be technically and operationally feasible and well tolerated by participants, in terms of burden and duration. Conclusions Findings of this feasibility assessment indicate that large-scale, detailed evaluations of cardiovascular risk, including a questionnaire and advanced central and peripheral hemodynamics, are feasible in a high-risk population in a middle-income setting.

RESUMEN Objetivos Determinar la factibilidad de evaluar el riesgo de enfermedades cardiovasculares en la población utilizando hemodinámica avanzada en el estudio Vida Sana en Suriname (HELISUR por su sigla en inglés). Métodos Este fue un estudio preliminar realizado de mayo a junio del 2012 empleando el método de factibilidad técnica, económica, legal, operativa y de programación (TELOS) para evaluar la factibilidad del HELISUR, un estudio poblacional transversal a gran escala de factores de riesgo y enfermedades cardiovasculares en Suriname. Suriname, un país de ingresos medianos de América del Sur, con una población de etnicidad principalmente africana y asiática, presenta un riesgo alto de enfermedades cardiovasculares. En el estudio participó un total de 135 voluntarios de 18 a 70 años de edad. Se puso a prueba un cuestionario de salud en un centro de atención primaria de salud, y se realizaron evaluaciones cardiovasculares no invasoras en un centro de salud académico. La evaluación cardiovascular incluyó mediciones de presión arterial en posición sentada, supina y de pie, y los criterios de valoración intermedios, como el gasto cardíaco, la resistencia vascular periférica, la velocidad de la onda de pulso y el índice de aumento. Resultados En las pruebas del método TELOS se encontró que la comunicación por teléfono celular era la más eficaz para asegurar la asistencia a las citas y que a menudo se requería la presencia de un entrevistador capacitado para ayudar a los voluntarios a llenar el cuestionario; se recomienda modificar las preguntas para que sean más claras. Con respecto a las evaluaciones cardiovasculares prolongadas de hemodinámica periférica y central, los resultados demostraron que eran técnica y operativamente factibles, y bien toleradas por los participantes en cuanto a la carga y duración. Conclusiones Los resultados de esta evaluación de factibilidad indican que las evaluaciones detalladas y a gran escala del riesgo de enfermedades cardiovasculares, que incluyen un cuestionario y hemodinámica central y periférica avanzada, son factibles para una población de alto riesgo en un país de ingresos medianos.

RESUMO Objetivos Determinar a viabilidade de avaliar o risco cardiovascular da população por meio de avaliação hemodinâmica avançada no Estudo de Vida Saudável no Suriname (HELISUR). Métodos Estudo preliminar realizado em maio-junho de 2012 com o uso da metodologia TELOS (análise técnica, financeira, jurídica, operacional e do cronograma) para avaliar a viabilidade do HELISUR – estudo transversal de base populacional em grande escala dos fatores de risco e doenças cardiovasculares no Suriname. O Suriname é um país sul-americano de renda média de população majoritariamente de origem afro-asiática com alto risco da doença cardiovascular. Participaram do estudo 135 voluntários com 18 a 70 anos de idade. O questionário sobre saúde foi testado em uma unidade básica de saúde e avaliações cardiovasculares não invasivas foram realizadas em um centro de saúde acadêmico. A avaliação cardiovascular consistiu da medida da pressão arterial em posição sentada, supino e em pé, e da medida de parâmetros (endpoints) intermediários como débito cardíaco, resistência vascular periférica, velocidade da onda de pulso e índice de amplificação. Resultados A análise TELOS indicou maior eficiência na adesão às consultas com a comunicação por celular e a necessidade frequente de auxílio de um entrevistador treinado para o preenchimento do questionário. Modificações para melhorar a compreensão das perguntas são recomendadas. Também se demonstrou que o amplo estudo da hemodinâmica central e periférica é viável do ponto de vista técnico e operacional e que os participantes toleram bem o incômodo e o tempo de avaliação. Conclusões Os resultados da avaliação de viabilidade indicam que a avaliação aprofundada do risco cardiovascular em grande escala, incluindo a administração de questionário e estudos de hemodinâmica avançada central e periférica, é viável em uma população de renda média com alto risco.

Exploring cardiovascular health: the Healthy Life in Suriname (HELISUR) study. A protocol of a cross-sectional study.

INTRODUCTION: Obesity, hypertension and diabetes are on a dramatic rise in low-income and middle-income countries, and this foretells an overwhelming increase in chronic disease burden from cardiovascular disease. Therefore, rapid action should be taken through preventive population-based programmes. However, in these regions, data on the population distribution of cardiovascular risk factors, and of intermediate and final end points for cardiovascular disease are scarce. The Healthy Life in Suriname (HELISUR) study is a cardiovascular population study in Suriname, which is part of the Caribbean Community. The HELISUR study is dedicated to provide data on risk factors and prevalent cardiovascular disease in the multiethnic population, which is mainly of African and Asian descent. METHODS AND ANALYSIS: In a cross-sectional, observational population-based setting, a random representative sample of 1800 citizens aged between 18 and 70 years will be selected using a cluster household sampling method. Self-reported demographic, socioeconomic and (cardiovascular) health-related data will be collected. Physical examination will include the assessment of cardiovascular risk factors and prevalent cardiovascular disease. In addition, we will study cardiovascular haemodynamics non-invasively, as a novel intermediate outcome. Finally, fasting blood and overnight urine samples will be collected to monitor cardiometabolic risk factors. The main outcome will be descriptive in reporting the prevalence of risk factors and measures of (sub) clinical end organ damage, stratified for ethnicity and sex-age groups. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the State Secretary of Health. Data analysis and manuscript submission are scheduled for 2016. Findings will be disseminated in peer-reviewed journals, and at national, regional and international scientific meetings. Importantly, data will be presented to Surinamese policymakers and healthcare workers, to develop preventive strategies to combat the rapid rise of cardiovascular disease.

Nonlinear mixed effects modeling of the diurnal blood pressure profile in a multiracial population.

BACKGROUND: Cardiac and cerebrovascular events in hypertensive patients are related to specific features of the 24-hour diurnal blood pressure (BP) profile (i.e., daytime and nighttime BP, nocturnal dip (ND), and morning surge (MS)). This investigation aimed to characterize 24-hour diurnal systolic BP (SBP) with parameters that correlate directly with daytime and nighttime SBP, ND, and MS using nonlinear mixed effects modeling. METHODS: Ambulatory 24-hour SBP measurements (ABPM) of 196 nontreated subjects from three ethnic groups were available. A population model was parameterized in NONMEM to estimate and evaluate the parameters baseline SBP (BSL), nadir (minimum SBP during the night), and change (SBP difference between day and night). Associations were tested between these parameters and patient-related factors to explain interindividual variability. RESULTS: The diurnal SBP profile was adequately described as the sum of 2 cosine functions. The following typical values (interindividual variability) were found: BSL = 139 mm Hg (11%); nadir = 122 mm Hg (14%); change = 25 mm Hg (52%), and residual error = 12 mm Hg. The model parameters correlate well with daytime and nighttime SBP, ND, and MS (R (2) = 0.50-0.92). During covariate analysis, ethnicity was found to be associated with change; change was 40% higher in white Dutch subjects and 26.8% higher in South Asians than in blacks. CONCLUSIONS: The developed population model allows simultaneous estimation of BSL, nadir, and change for all individuals in the investigated population, regardless of individual number of SBP measurements. Ethnicity was associated with change. The model provides a tool to evaluate and optimize the sampling frequency for 24-hour ABPM.

Field testing in Suriname of two blood pressure-measuring devices for low-resource and middle-resource countries, according to a WHO protocol.

INTRODUCTION: High blood pressure (BP) is known to be the greatest modifiable risk factor of cardiovascular diseases, of which 80% occur in low-resource and middle-resource settings. Yet, BP measurement in these countries remains extremely poor. In 2005, a WHO committee invited manufacturers to produce devices especially for use in low-resource settings. Our study assesses the accuracy, performance, and acceptability of two submitted oscillometric devices under field circumstances in Suriname (South America), namely, the Microlife BP 3AS1-2 and Omron HEM-SOLAR. METHODS: We compared BP measurements of test devices using a conventional Mercury sphygmomanometer, performed by local healthcare workers under field circumstances. Three hundred and forty-two individuals were included. Statistics included t-tests, analysis of variance, and Bland-Altman plots. RESULTS: The mean systolic/diastolic BP differences (SD) were -3.5 (8.0)/-7.0 (6.0) for Omron versus Mercury and -6.4 (7.8)/-6.5 (6.0) mmHg for Microlife versus Mercury. Microlife was more accepted by healthcare workers, and both devices performed adequately under field conditions. DISCUSSION AND CONCLUSION: The acceptability, durability, and performance of both test devices were adequate. However, Microlife BP 3AS1-2 underestimated systolic pressure almost twice as much compared with Omron HEM-SOLAR, with identical diastolic underestimations. Guaranteed global availability, users could make a choice between the Omron HEM-SOLAR being more accurate in BP measurement, and Microlife BP 3AS1-2 being more accepted by healthcare workers.

Genetic factors are relevant and independent determinants of antihypertensive drug effects in a multiracial population.

BACKGROUND: The success of antihypertensive drugs may be improved by better prediction of their efficacy in individual patients. The objective of our study was to determine whether genetic variation predicts the individual systolic blood pressure (SBP) response to antihypertensive drugs and to assess to what extent the individual treatment response could be explained by the combined effects of known demographic, environmental, and genetic factors. METHODS: A population-based, crossover, open-label randomized treatment study stratified for ethnicity in 102 mildly hypertensive patients aged 35-60 years in an outpatient hypertension clinic (the ROTATE study). Patients underwent five successive 6-week treatment episodes of single-drug treatment in a randomized order with representatives of the major antihypertensive drug classes. The primary outcome measure was the DeltaSBP after 6-week drug therapy. RESULTS: Participants (n = 97) completed 407 treatment episodes. The estimated unpredictable natural variation of SBP within individuals was 65% of the total study variance. The primary analysis model that considered the effects of environmental, demographic, and genetic factors and their interactions to SBP response to antihypertensive drugs, explained 23% of the total variance accounting for 66% of the predictable variance. Ethnicity, low sodium intake, and ADD1 614G-->T polymorphism were the only drug-related predictors. A number of genetic variants (ADD1 614G-->T, ADRB1 145A-->G, ADRB2 79C-->G, CYP11B2 -344C-->T, and SLC12A3 78G-->A) contributed significantly (9%) to the total variance of the SBP response. The contribution of each individual single-nucleotide polymorphism (SNP) ranged from 1.1 to 2.4%. CONCLUSIONS: Genetic factors are relevant and independent determinants of antihypertensive drug effects in a multiracial population.

Distribution of creatine kinase in the general population: implications for statin therapy.

BACKGROUND: Eligible subjects with mildly elevated serum creatine kinase (CK) activity are often excluded before randomization in statin trials, but patients may potentially be misclassified as having hyperCKemia when inappropriate reference limits are used. Little information is usually given regarding how reference limit data were established, although evidence suggests that the variation of CK activity in the general population is wider than reflected in reference intervals in current use. METHODS: We determined reference intervals for serum CK according to National Committee on Clinical Laboratory Standards/Nordic Reference Interval Project guidelines, in a stratified random sample of the population, including 1444 individuals, aged 34 to 60 years, after 3 days of rest. Participants were mainly of white European (n = 503), South Asian (n = 292), or African descent (n = 580). RESULTS: The calculated upper reference limits (97.5th percentile) for nonblack and black women and men were 2 to 5 times higher than recommended by the assay manufacturer. Respectively 13% of the white Europeans, 23% of South Asians, and 49% of the black people had serum CK activities above the manufacturer-provided limits. CONCLUSION: The variation in CK activity within the population is wider than previously suggested in smaller, nonrandom samples, and relatively high values occur frequently in all subgroups studied after rest. Therefore, we infer that upward adjustment of the upper reference limit is necessary for all population subgroups studied. The use of appropriately established reference intervals may improve the use of statins and particularly benefit the control of dyslipidemia in those with relatively high baseline CK activity.

Creatine kinase activity is associated with blood pressure.

BACKGROUND: We previously hypothesized that high activity of creatine kinase, the central regulatory enzyme of energy metabolism, facilitates the development of high blood pressure. Creatine kinase rapidly provides adenosine triphosphate to highly energy-demanding processes, including cardiovascular contraction, and antagonizes nitric oxide-mediated functions. Relatively high activity of the enzyme, particularly in resistance arteries, is thought to enhance pressor responses and increase blood pressure. Tissue creatine kinase activity is reported to be high in black people, a population subgroup with greater hypertension risk; the proposed effects of high creatine kinase activity, however, are not "race dependent." We therefore assessed whether creatine kinase is associated with blood pressure in a multiethnic population. METHODS AND RESULTS: We analyzed a stratified random sample of the population of Amsterdam, The Netherlands, consisting of 1444 citizens (503 white European, 292 South Asian, 580 black, and 69 of other ethnicity) aged 34 to 60 years. We used linear regression analysis to investigate the association between blood pressure and normal serum creatine kinase after rest, as a substitute measure of tissue activity. Creatine kinase was independently associated with blood pressure, with an increase in systolic and diastolic pressure, respectively, of 8.0 (95% CI, 3.3 to 12.7) and 4.7 (95% CI, 1.9 to 7.5) mm Hg per log creatine kinase increase after adjustment for age, sex, body mass index, and ethnicity. CONCLUSIONS: Creatine kinase is associated with blood pressure. Further studies are needed to explore the nature of this association, including how variation in cardiovascular creatine kinase activity may affect pressor responses.