Seroprevalence of human leptospirosis in a rural community from Tandil, Argentina. Assessment of risk factors and spatial analysis / Seroprevalencia de leptospirosis humana en una comunidad rural del partido de Tandil (Argentina). Identificación de los factores de riesgo y del análisis espacial

Abstract Leptospirosis is a neglected zoonosis that is widely distributed in the world. Although it is endemic in Argentina, prevalence remains unknown. The aims of the study were: (i) to determine the prevalence of leptospirosis in humans from a rural community in Tandil Argentina, (ii) to identify infecting Leptospira spp. serogroups, (iii) to identify factors associated with the infection, (iv) to estimate the population attributable fraction (PAF) of the risk factors and (v) to determine the spatial patterns of disease presentation and related risk factors. Blood samples from 202 participants were collected. A survey was conducted to obtain clinical and epidemiological data. Serological testing was performed by the microscopic agglutination test (MAT). Univariate and multivariate methods were applied to evaluate associations. Spatial clusters were investigated for seroprevalence and risk factors. Antibodies were found in 32.2% of participants (95% CI: 25.8-39.1). The most prevalent serogroup was Hebdomadis followed by Sejroe; Icterohaemorrhagiae; Tarassovi and Canicola. Living at lower altitudes (OR: 13.04; 95% CI: 2.60-65.32); not having access to water supply network (OR: 2.95; 95% CI: 1.30-6.69); living close to flooded streets (OR: 2.94; 95% CI: 1.14-7.69) and practicing water sports (OR: 3.12; 95% CI: 1.12-8.33) were associated with seropositivity. Factors related with housing characteristics, services and infrastructure had the higher PAF (from 17% to 81%). A spatial cluster with higher rates of positivity and of the main risk factors was determined. This work contributes useful data for specific preventive measures that should be implemented for the control of the disease.

Resumen La leptospirosis es una enfermedad desatendida, ampliamente distribuida a nivel mundial. Aunque es endémica en Argentina, su prevalencia es desconocida. Los objetivos de este estudio fueron los siguientes: (i) determinar la prevalencia de leptospirosis humana en comunidades rurales del partido de Tandil (Argentina), (ii) identificar serogrupos infectantes de Leptospira spp., (iii) identificar factores de riesgo asociados, (iv) estimar la fracción atribuible poblacional (FAP) de los factores de riesgo y (v) determinar los patrones espaciales de la enfermedad y de los factores de riesgo. Se tomaron muestras de sangre a 202 personas, y se registró información clínica y epidemiológica. El diagnóstico se realizó por microaglutinación (MAT). Para evaluar asociaciones, se utilizaron métodos univariados y multivariados. Se estudiaron clusters espaciales de la seroprevalencia y de los factores de riesgo. El 32,2% de los participantes (IC 95%: 25,8-39,1) presentaron anticuerpos. Los serogrupos más prevalentes fueron Hebdomadis, Sejroe, Icterohaemorrhagiae, Tarassovi y Canicola. Vivir a menores altitudes (OR: 13,04; IC 95%: 2,60-65,32) y cerca de calles inundables (OR: 2,94; IC 95%: 1,14-7,69), la falta de acceso a agua de red (OR: 2,95; IC 95%: 1,30-6,69) y la práctica de deportes acuáticos (OR: 3,12; IC 95%: 1,12-8,33) estuvieron asociados con la seropositividad. Factores relacionados con las características de las viviendas, los servicios y la infraestructura tuvieron mayor proporción de FAP (17 al 81%). Se encontró un área de mayor riesgo de presentación de individuos seropositivos y de los principales factores de riesgo. Este trabajo provee información útil para generar medidas preventivas específicas que podrían ser aplicadas para controlar esta enfermedad.

Seroprevalence of human leptospirosis in a rural community from Tandil, Argentina. Assessment of risk factors and spatial analysis.

Leptospirosis is a neglected zoonosis that is widely distributed in the world. Although it is endemic in Argentina, prevalence remains unknown. The aims of the study were: (i) to determine the prevalence of leptospirosis in humans from a rural community in Tandil Argentina, (ii) to identify infecting Leptospira spp. serogroups, (iii) to identify factors associated with the infection, (iv) to estimate the population attributable fraction (PAF) of the risk factors and (v) to determine the spatial patterns of disease presentation and related risk factors. Blood samples from 202 participants were collected. A survey was conducted to obtain clinical and epidemiological data. Serological testing was performed by the microscopic agglutination test (MAT). Univariate and multivariate methods were applied to evaluate associations. Spatial clusters were investigated for seroprevalence and risk factors. Antibodies were found in 32.2% of participants (95% CI: 25.8-39.1). The most prevalent serogroup was Hebdomadis followed by Sejroe; Icterohaemorrhagiae; Tarassovi and Canicola. Living at lower altitudes (OR: 13.04; 95% CI: 2.60-65.32); not having access to water supply network (OR: 2.95; 95% CI: 1.30-6.69); living close to flooded streets (OR: 2.94; 95% CI: 1.14-7.69) and practicing water sports (OR: 3.12; 95% CI: 1.12-8.33) were associated with seropositivity. Factors related with housing characteristics, services and infrastructure had the higher PAF (from 17% to 81%). A spatial cluster with higher rates of positivity and of the main risk factors was determined. This work contributes useful data for specific preventive measures that should be implemented for the control of the disease.

The effects of age on pulse wave velocity in untreated hypertension.

Increased arterial stiffness is an important determinant of cardiovascular risk, able to predict morbidity and mortality, and closely associated with ageing and blood pressure. The aims of this study were: (1) To determine the age-dependent reference pulse wave velocity (PWV), and compare it with values from hypertensive patients, and (2) to evaluate the impact of isolated and untreated hypertension on arterial stiffness. A total of 1079 patients were enrolled and divided into a control group (NT) of asymptomatic normotensive patients and a group of asymptomatic hypertensive patients (HT). Blood pressure, carotid-femoral PWV, and body mass index were measured in each subject, whose blood was drawn for laboratory tests. Aortic mean PWV in the NT group was 6.85 ± 1.66 m/s, which increased linearly (R2  = 0.62; P < .05) with age. In patients over 50 years of age, PWV was significantly higher than in younger patients (8.35 vs 5.92 m/s, respectively, P < .001). This significant difference persisted when observing male and female patients separately. In the hypertensive group, mean PWV value was 8.04 ± 1.8 m/s (range 4.5-15.8 m/s) and increased (R2  = 0.243; P < .05) with age. The PWV increase in HT was significantly higher (0.93 m/s per decade, P < .001) than in NT (0.44 m/s per decade). Our study provides normal values of PVW per decade, and shows that these values increase with age, especially after 50 years of age, particularly in HT patients. This stiffness growth rate may be responsible for increased cardiovascular risk in both groups.

Arterial Stiffness in a Rural Population of Argentina: Pilot Study.

INTRODUCTION: Aortic stiffness evaluated through pulse wave velocity (PWV) measurement is nowadays accepted as a reliable parameter to estimate cardiovascular risk. However the data about arterial stiffness in South America come from urban populations. AIMS: To determine the relationship between PWV changes and ageing and to identify the rate of change in each decade of life. METHODS: PWV was measured in the carotid-femoral pathway in 400 inhabitants of Vela town and clinical parameters were recorded. RESULTS: The prevalence of hypertension, dyslipidemia and diabetes was 33.5, 17.5, 5% respectively. PWV was positively correlated with age (r: 0.817, p = 0.01) and was greater after the fifth decade of life (9.72 ± 2.2 vs. 5.87 ± 1.55 m/s; p: 0.001) than in youngers than 50 years, respectively. The risk (odds ratio) of having PWV >10 m/s was higher in hypertensives (OR: 50, p = 0.001), older than 50 years (OR: 44, p = 0.001), diabetics (OR 9.5, p = 0.001) and dyslipidemic patients (OR: 5, p = 0.001). CONCLUSIONS: This is the first study in a rural population of Argentina which determines the relationship of PWV with age and cardiovascular risk. PWV shows a slower growth in subjects less than 50 years compared to older adults with a strong relationship to the process of arterial aging, the development of hypertension and cardiovascular risk.

Corrigendum to "reference values of pulse wave velocity in healthy people from an urban and rural argentinean population".

[This corrects the article DOI: 10.1155/2014/653239.].

Reference values of pulse wave velocity in healthy people from an urban and rural argentinean population.

In medical practice the reference values of arterial stiffness came from multicenter registries obtained in Asia, USA, Australia and Europe. Pulse wave velocity (PWV) is the gold standard method for arterial stiffness quantification; however, in South America, there are few population-based studies. In this research PWV was measured in healthy asymptomatic and normotensive subjects without history of hypertension in first-degree relatives. Normal PWV and the 95% confidence intervals values were obtained in 780 subjects (39.8 ± 18.5 years) divided into 7 age groups (10-98 years). The mean PWV found was 6.84 m/s ± 1.65. PWV increases linearly with aging with a high degree of correlation (r (2) = 0.61; P < 0.05) with low dispersion in younger subjects. PWV progressively increases 6-8% with each decade of life; this tendency is more pronounced after 50 years. A significant increase of PWV over 50 years was demonstrated. This is the first population-based study from urban and rural people of Argentina that provides normal values of the PWV in healthy, normotensive subjects without family history of hypertension. Moreover, the age dependence of PWV values was confirmed.

Prevalence of hypertension in rural populations from Ibero-America and the Caribbean.

INTRODUCTION: Hypertension and cardiovascular risk factors are widespread in developing countries, but little is known about cardiovascular risk profiles in rural communities from Ibero-America and the Caribbean. The aim of the present study was to evaluate the peer-reviewed literature published from 1990 to 2012 relating to the prevalence of hypertension in rural populations from Ibero-America and the Caribbean. METHODS: A bibliographic search was conducted in MEDLINE, SCIELO and LILACS databases. Included were population-based studies in which prevalence of hypertension in adults was reported. RESULTS: A total of 30 peer-reviewed publications were identified that reported the prevalence of hypertension in 33 143 patients. The crude hypertension prevalence reported from rural Ibero-America was 32.6% (95% confidence interval: 31.4-32.5%; range: 1.8-52%). The prevalence of hypertension was lower in aboriginal populations than in other rural communities (19.5% vs 36%). Only nine studies assessed the awareness, treatment, and level of control of hypertension (means 54%, 57%, and 14% respectively). The most prevalent cardiovascular risk factors were abdominal obesity (39%) and overweight (39%). CONCLUSIONS: Hypertension is of public health importance in rural Ibero-America and the Caribbean, with evidence of considerable under-diagnosis, treatment, and control. There is an urgent need to develop strategies to prevent, detect, treat, and control hypertension effectively in this region.

High blood pressure, overweight and obesity among rural scholars from the Vela Project: a population-based study from South America.

BACKGROUND: Many studies have shown that high blood pressure and overweight begins in childhood. Consequently, it is useful to know blood pressure and body mass index (BMI) values from an early age. There are few data about blood pressure control in children and adolescents from rural populations in South America. AIM: The objective of this study was to determine the prevalence of high blood pressure and its association with sedentary habits and overweight/obesity in scholars from a rural population in Argentina. METHODS: The study population for this cross-sectional study was composed of rural children and adolescent scholars from Maria Ignacia Vela. Pre-hypertension and hypertension were defined on the basis of percentiles from the average of three blood pressure measurements taken on a single occasion. In patients with three blood pressure measurements above the 90th percentile, ambulatory blood pressure monitoring was performed to confirm hypertension or pre-hypertension. BMI was categorized by using the 2000 Centers for Disease Control and Prevention growth charts. RESULTS: We studied 334 scholars (aged 5-18 years). Mean age was 11.4 years. In 70% of the subjects, blood pressure had never been measured. The prevalence of high blood pressure was 4.4%. Students with sedentary habits were 3.67-fold more likely to develop high blood pressure than their physically active counterparts (odds ratio [OR] 3.67; 95% CI 1.08, 12.46; p = 0.037). Obese students were more likely to develop hypertension than the students with normal weight (OR = 5.17; 95% CI 1.52, 17.60; p = 0.02). Male students had a 3.4-fold higher risk of developing high blood pressure than females. CONCLUSIONS: In our rural population, the evaluation of blood pressure in children and adolescents is not a routine measure. Our data indicate a low prevalence of high blood pressure. These data could argue differences between rural and urban scholars. Our data demonstrate a close relationship between increased overweight, obesity and sedentary lifestyle with the development of high blood pressure. We emphasize the importance of blood pressure controls and the need to implement programmes to modify sedentary lifestyle in rural populations.

[Blood pressure control and arterial hypertension in children and adolescents from a rural population in Argentina: preliminary data from Vela Proyect]. / Control de la presión arterial y prevalencia de hipertensión arterial en niños y adolescentes de una población rural de Argentina: Datos preliminares del Proyecto Vela.

Hypertension can start at an early age, however there are few data about blood pressure control in rural students in Argentina. Proyecto Vela is a survey about cardiovascular risk factors in the rural population of Maria Ignacia Vela, Argentina. We evaluated blood pressure levels, prevalence of arterial hypertension, sedentary lifestyle, overweight, and obesity in 331 children and adolescent students. In 70% of the subjects the blood pressure was measured for the first time. Prevalence of arterial hypertension was 4.3% in adolescents. Pre-hypertension was detected in 1.9% and 1.7% of children and adolescents, respectively. The prevalence of smoking, sedentary lifestyle, overweight or obesity was 2.4%, 50% and 23.8% respectively. There was association (p <0.05) between hypertension and sedentary lifestyle. In our population the evaluation of blood pressure in adolescents is not a routine procedure. Prevalence of hypertension was low but these data show the importance of blood pressure controls and the need of official programs to modify sedentary lifestyle.

Control de la presión arterial y prevalencia de hipertensión arterial en niños y adolescentes de una población rural de Argentina: datos preliminares del Proyecto Vela / Blood pressure control and arterial hypertension in children and adolescents from a rural population in Argentina: preliminary data from Vela Proyect

La hipertensión arterial puede iniciarse a temprana edad. Existen pocos datos sobre el control de la presión arterial en poblaciones escolares rurales argentinas. Proyecto Vela es un estudio epidemiológico que evalúa la prevalencia de factores de riesgo cardiovascular en la población rural de María Ignacia Vela, Argentina. Se midieron niveles de presión arterial, prevalencia de hipertensión arterial, sedentarismo y sobrepeso en 331 niños y adolescentes escolares. En el 70 por ciento, la presión arterial se midió por primera vez. La prevalencia de hipertensión fue 4,3 por ciento y la de prehipertensión 1,9 por ciento en niños y 1,7 por ciento en adolescentes. Las prevalencias de tabaquismo, sedentarismo y sobrepeso fueron 2,4 por ciento, 50 por ciento y 23,8 por ciento, respectivamente. Hubo asociación entre sedentarismo e hipertensión arterial (p menor 0,05). La prevalencia de hipertensión fue baja, pero destacamos la importancia de medir la presión arterial desde edades tempranas e implementar programas oficiales para modificar el sedentarismo.

Control de la presión arterial y prevalencia de hipertensión arterial en niños y adolescentes de una población rural de Argentina: datos preliminares del Proyecto Vela / Blood pressure control and arterial hypertension in children and adolescents from a rural population in Argentina: preliminary data from Vela Proyect

La hipertensión arterial puede iniciarse a temprana edad. Existen pocos datos sobre el control de la presión arterial en poblaciones escolares rurales argentinas. Proyecto Vela es un estudio epidemiológico que evalúa la prevalencia de factores de riesgo cardiovascular en la población rural de María Ignacia Vela, Argentina. Se midieron niveles de presión arterial, prevalencia de hipertensión arterial, sedentarismo y sobrepeso en 331 niños y adolescentes escolares. En el 70 por ciento, la presión arterial se midió por primera vez. La prevalencia de hipertensión fue 4,3 por ciento y la de prehipertensión 1,9 por ciento en niños y 1,7 por ciento en adolescentes. Las prevalencias de tabaquismo, sedentarismo y sobrepeso fueron 2,4 por ciento, 50 por ciento y 23,8 por ciento, respectivamente. Hubo asociación entre sedentarismo e hipertensión arterial (p menor 0,05). La prevalencia de hipertensión fue baja, pero destacamos la importancia de medir la presión arterial desde edades tempranas e implementar programas oficiales para modificar el sedentarismo.(AU)