Sustained Domestic Vector Exposure Is Associated With Increased Chagas Cardiomyopathy Risk but Decreased Parasitemia and Congenital Transmission Risk Among Young Women in Bolivia.

BACKGROUND: We studied women and their infants to evaluate risk factors for congenital transmission and cardiomyopathy in Trypanosoma cruzi-infected women. METHODS: Women provided data and blood for serology and quantitative polymerase chain reaction (PCR). Infants of infected women had blood tested at 0 and 1 month by microscopy, PCR and immunoblot, and serology at 6 and 9 months. Women underwent electrocardiography (ECG). RESULTS: Of 1696 women, 456 (26.9%) were infected; 31 (6.8%) transmitted T. cruzi to their infants. Women who transmitted had higher parasite loads than those who did not (median, 62.0 [interquartile range {IQR}, 25.8-204.8] vs 0.05 [IQR, 0-29.6]; P < .0001). Transmission was higher in twin than in singleton births (27.3% vs 6.4%; P = .04). Women who had not lived in infested houses transmitted more frequently (9.7% vs 4.6%; P = .04), were more likely to have positive results by PCR (65.5% vs 33.9%; P < .001), and had higher parasite loads than those who had lived in infested houses (median, 25.8 [IQR, 0-64.1] vs 0 [IQR, 0-12.3]; P < .001). Of 302 infected women, 28 (9.3%) had ECG abnormalities consistent with Chagas cardiomyopathy; risk was higher for older women (odds ratio [OR], 1.06 [95% confidence interval {CI}, 1.01-1.12] per year) and those with vector exposure (OR, 3.7 [95% CI, 1.4-10.2]). We observed a strong dose-response relationship between ECG abnormalities and reported years of living in an infested house. CONCLUSIONS: We hypothesize that repeated vector-borne infection sustains antigen exposure and the consequent inflammatory response at a higher chronic level, increasing cardiac morbidity, but possibly enabling exposed women to control parasitemia in the face of pregnancy-induced Th2 polarization.

Usefulness for surveillance of hypertension prevalence studies in Latin America and the Caribbean: the past 10 years / Utilidad de los estudios de prevalencia para la vigilancia de la hipertensión en América Latina y el Caribe: los 10 últimos años

OBJECTIVE: To compare the usefulness for surveillance of the peer-reviewed literature on the prevalence of hypertension in Latin America and the Caribbean published from 2001 to 2010 with a previous study of the published literature from 1962 to 2000. METHODS: A bibliographic search was conducted of publications from 2001 to 2010 that examined the prevalence of hypertension using MEDLINE and LILACS databases. The methodology of each paper was evaluated with the same critical appraisal tool used in the previous study. RESULTS: A total of 81 papers were published from 2001 to 2010 on the prevalence of hypertension in Latin America and the Caribbean. Only 24 of these studies met the minimum methodologic criteria for evaluation. While the total number of studies published in the past 10 years exceeds the number published from 1962 to 2000, the percentage of studies that met the minimum methodologic criteria has not substantially increased. In addition to major methodologic shortcomings, less than 46% of the published studies reported rates of awareness, treatment, and control of hypertension. The hypertension prevalence estimates from the peer-reviewed literature range from 7% to 49%. These studies were primarily done in urban centers and are not evenly distributed throughout the region. CONCLUSIONS: The quality and geographic distribution of the published literature on the prevalence of hypertension in Latin America and the Caribbean are inadequate. Research resources and efforts should be directed in the future toward closing this gap.

OBJETIVO: Comparar la utilidad para la vigilancia epidemiológica de los artículos sobre prevalencia de hipertensión en América Latina y el Caribe publicados en revistas con arbitraje científico del 2001 al 2010, con un estudio anterior de la bibliografía publicada en el período 1962-2000. MÉTODOS: En las bases de datos MEDLINE y LILACS se efectuó una búsqueda bibliográfica de los artículos que examinaron la prevalencia de hipertensión publicados del 2001 al 2010. La metodología empleada en cada artículo se valoró con la misma herramienta de evaluación usada en el estudio anterior. RESULTADOS: Del 2001 al 2010 se publicaron 81 artículos sobre la prevalencia de la hipertensión en América Latina y el Caribe. Solo 24 de estos estudios cumplieron los criterios metodológicos mínimos para la evaluación. Aunque en los 10 últimos años se publicaron más estudios que en el período 1962-2000, el porcentaje de estudios que cumplieron los criterios metodológicos mínimos no aumentó sustancialmente. Además de presentar deficiencias metodológicas importantes, menos de 46% de los estudios publicados incluyeron información sobre la concientización, el tratamiento y el control de la hipertensión. Las estimaciones sobre la prevalencia de hipertensión en los artículos estudiados varían entre 7% y 49%. Estos estudios se realizaron principalmente en centros urbanos y no se distribuyeron de manera uniforme en toda la región. CONCLUSIONES: La bibliografía publicada sobre la prevalencia de la hipertensión en América Latina y el Caribe es insuficiente para ser útil con fines de vigilancia, y su calidad y la distribución geográfica son inadecuadas. En el futuro, los recursos y los esfuerzos de investigación deben enfocarse en reducir esta diferencia.