Temporal trends and spatial clusters of gastric cancer mortality in Brazil / Tendencias temporales y conglomerados espaciales de mortalidad por cáncer gástrico en Brasil / Tendências temporais e aglomerados espaciais de mortalidade por câncer gástrico no Brasil

ABSTRACT Objective. To identify nationwide temporal trends and spatial patterns of gastric cancer-related mortality in Brazil. Methods. An ecological study was performed using death certificates registered from 2000 to 2019 in which gastric cancer was recorded as any cause of death (an underlying or associated cause). Trends over time were assessed using joinpoint regression models. Spatial and spatiotemporal clusters were identified by Kulldorff's space-time scan statistics to identify high-risk areas. Results. In 276 897/22 663 091 (1.22%) death certificates gastric cancer was recorded as any cause of death. Age-adjusted gastric cancer-related mortality increased significantly over time (annual percentage change [APC]: 0.7, 95% confidence interval [CI]: 0.5 to 0.8). The increase in mortality was more pronounced in the less-developed North and Northeast Regions (North Region, APC: 3.1, 95% CI: 2.7 to 3.5; Northeast Region, APC: 3.1, 95% CI: 2.5 to 3.7). Eight spatiotemporally associated high-risk clusters of gastric cancer-related mortality were identified in the North, South, Northeast and Central-West Regions, as well as a major cluster covering a wide geographical range in the South and Southeast Regions of Brazil during the first years of the study period (2000 to 2009). Conclusions. More recently, during 2010 to 2019, clusters of gastric cancer have been identified in the Northeast Region. The nationwide increase in mortality in this analysis of 20 years of data highlights the persistently high burden of gastric cancer in Brazil, especially in socioeconomically disadvantaged regions. The identification of these areas where the population is at high risk for gastric cancer-related mortality emphasizes the need to develop effective and intersectoral control measures.

RESUMEN Objetivo. Identificar las tendencias temporales y los patrones espaciales de la mortalidad relacionada con el cáncer gástrico a nivel nacional en Brasil. Métodos. Se realizó un estudio ecológico, empleando certificados de defunción registrados entre los años 2000 y 2019 en los que se notificó cáncer gástrico como cualquier causa de muerte (subyacente o asociada). Se evaluaron las tendencias con el transcurso del tiempo mediante modelos de regresión de punto de inflexión (joinpoint). Se identificaron los conglomerados espaciales y espaciotemporales mediante la técnica estadística de exploración espaciotemporal de Kulldorff para determinar cuáles eran las áreas de alto riesgo. Resultados. En 276 897 de 22 663 091 certificados de defunción (1,22%), se registró cáncer gástrico como cualquier causa de muerte. La mortalidad relacionada con el cáncer gástrico ajustada por edad aumentó significativamente con el tiempo (cambio porcentual anual: 0,7; intervalo de confianza [IC] del 95%: 0,5 a 0,8). El aumento de la mortalidad fue más acusado en la regiones Norte y Noreste, menos desarrolladas, (región Norte, cambio porcentual anual: 3,1, IC del 95%: 2,7 a 3,5; región Noreste, cambio porcentual anual: 3,1, IC del 95%: 2,5 a 3,7). Durante los primeros años del período de estudio (del 2000 al 2009), se identificaron ocho conglomerados de alto riesgo de mortalidad relacionada con el cáncer gástrico y con asociación espacial y temporal en las regiones Norte, Sur, Noreste y Centro-Oeste, así como un conglomerado importante que cubría un amplio rango geográfico en las regiones Sur y Sureste de Brasil. Conclusiones. Más recientemente, del 2010 al 2019, se han identificado conglomerados de cáncer gástrico en la región noreste. El aumento nacional de la mortalidad en este análisis de veinte años de datos destaca la carga persistentemente alta del cáncer gástrico en Brasil, especialmente en las regiones socioeconómicamente desfavorecidas. La identificación de estas áreas en que la población presenta un alto riesgo de mortalidad relacionada con el cáncer gástrico subraya la necesidad de elaborar medidas de control intersectoriales y efectivas.

RESUMO Objetivo. Identificar tendências temporais e padrões espaciais de mortalidade relacionada ao câncer gástrico em todo o Brasil. Métodos. Realizou-se um estudo ecológico a partir de declarações de óbito registradas de 2000 a 2019 em que o câncer gástrico foi indicado como qualquer causa de morte (causa básica ou associada). As tendências ao longo do tempo foram avaliadas a partir de modelos de regressão por pontos de inflexão (joinpoint). Os aglomerados espaciais e espaço-temporais foram identificados por estatística de varredura espaço-temporal de Kulldorff para detectar áreas de alto risco. Resultados. O câncer gástrico foi registrado como qualquer causa de morte em 276.897/22.663.091 (1,22%) declarações de óbito. A mortalidade relacionada ao câncer gástrico ajustada por idade aumentou significativamente ao longo do tempo [variação percentual anual (VPA): 0,7, intervalo de confiança (IC) de 95%: 0,5 a 0,8]. O aumento da mortalidade foi mais acentuado no Norte e Nordeste, regiões menos desenvolvidas (região Norte, VPA: 3,1, IC 95%: 2,7 a 3,5; região Nordeste, VPA: 3,1, IC 95%: 2,5 a 3,7). Identificaram-se oito aglomerados de alto risco de mortalidade relacionada ao câncer gástrico em associação espaço-temporal nas regiões Norte, Sul, Nordeste e Centro-Oeste, além de um grande aglomerado que abrangia uma larga faixa geográfica nas regiões Sul e Sudeste do Brasil durante os primeiros anos do período de estudo (2000 a 2009). Conclusões. Mais recentemente, no período de 2010 a 2019, identificaram-se aglomerados de câncer gástrico na região Nordeste. O aumento da mortalidade em todo o país nesta análise de dados relativos a 20 anos evidencia a persistência da alta carga de câncer gástrico no Brasil, sobretudo em regiões desfavorecidas do ponto de vista socioeconômico. A identificação dessas áreas em que a população corre alto risco de morte relacionada ao câncer gástrico enfatiza a necessidade de desenvolver medidas de controle efetivas e intersetoriais.

Clarithromycin-resistant H. pylori primary strains and virulence genotypes in the Northeastern region of Brazil

ABSTRACT The increase of H. pylori resistance to clarithromycin is a concern. This study evaluated the prevalence of H. pylori's primary resistance to clarithromycin and its association with virulence factors in adult dyspeptic patients and asymptomatic children. The gastric mucosa from patients (153 gastritis, 24 gastric cancer, 21 peptic ulcer) and gastric juice obtained by string test from 24 H. pylori and 23S rRNA positive asymptomatic children were included. The clarithromycin resistance was assessed by TaqMan RT-PCR 23S rRNA point mutations, A2142G and/or A2143G, and H. pylori virulence markers by PCR. Overall, the clarithromycin resistance was 14.4% (32/222), 14.2% in adults, and 12% in children, whereas origin, gender, and disease were not distinctive factors. The most prevalent point mutation was A2143G (62.5%). The point mutation was significantly less frequent in cagA-positive (11.4%) than in cagA-negative (23.6%) strains (p=0.03 OR = 0.4 95%CI = 0.19 - 0.91) as well as in cagE-positive (10.2%), cagE-negative (21.2%) (p=0.03 OR: 0.4 I.C:0.20-0.91). No difference was found in iceA or vacA alleles genotypes. Primary resistance to clarithromycin was lower than that reported in Southeast Brazil. The cagA and cagE positive H. pylori samples have few point mutations suggesting that individuals infected with virulent strains may be more susceptible to anti-H. pylori treatment.

CagA phosphorylation EPIYA-C motifs and the vacA i genotype in Helicobacter pylori strains of asymptomatic children from a high-risk gastric cancer area in northeastern Brazil

Helicobacter pylori infection is one of the most common infections worldwide and is associated with gastric diseases. Virulence factors such as VacA and CagA have been shown to increase the risk of these diseases. Studies have suggested a causal role of CagA EPIYA-C in gastric carcinogenesis and this factor has been shown to be geographically diverse. We investigated the number of CagA EPIYA motifs and the vacA i genotypes in H. pylori strains from asymptomatic children. We included samples from 40 infected children (18 females and 22 males), extracted DNA directly from the gastric mucus/juice (obtained using the string procedure) and analysed the DNA using polymerase chain reaction and DNA sequencing. The vacA i1 genotype was present in 30 (75%) samples, the i2 allele was present in nine (22.5%) samples and both alleles were present in one (2.5%) sample. The cagA-positive samples showed distinct patterns in the 3’ variable region of cagA and 18 of the 30 (60%) strains contained 1 EPIYA-C motif, whereas 12 (40%) strains contained two EPIYA-C motifs. We confirmed that the studied population was colonised early by the most virulent H. pylori strains, as demonstrated by the high frequency of the vacA i1 allele and the high number of EPIYA-C motifs. Therefore, asymptomatic children from an urban community in Fortaleza in northeastern Brazil are frequently colonised with the most virulent H. pylori strains. .

Helicobacter pylori vacA and cagA genotypes in patients from northeastern Brazil with upper gastrointestinal diseases

Helicobacter pylori causes chronic gastric inflammation and significantly increases the risk of duodenal and gastric ulcer disease and distal gastric carcinoma. In this study, we evaluated the Helicobacter pylori vacA and cagA genotypes in patients from a Brazilian region where there is a high prevalence of gastric cancer. Polymerase chain reaction (PCR) was used to investigate vacA mosaicism and cagA status in the gastric mucosa of 134 H. pylori-positive patients, including 76 with gastritis: 28 with peptic ulcer disease and 30 with gastric cancer. The s1m1 variant was the predominant vacA genotype observed, whereas the s1 allele was more frequently observed in patients with more severe diseases associated with H. pylori infection [p = 0.03, odds ratio (OR) = 5.72, 95% confidence interval (CI) = 1.15-38.60]. Furthermore, all of the s1 alleles were s1b. Mixed vacA m1/m2 strains were found more frequently in patients with gastric cancer and a cagA-positive status was significantly associated with gastric cancer (p = 0.016, OR = 10.36, 95% CI = 1.35-217.31). Patients with gastric cancer (21/21, 100%, p = 0.006) or peptic ulcers (20/21, 95%, p = 0.02) were more frequently colonised by more virulent H. pylori strains compared to gastritis patients (41/61, 67.2%). In conclusion, in the northeastern of Brazil, which is one of the regions with the highest prevalence of gastric cancer in the country, infection with the most virulent H. pylori strains, carrying the cagA gene and s1m1 vacA alleles, predominates and is correlated with more severe H. pylori-associated diseases.

The presence of Helicobacter pylori in the liver depends on the Th1, Th17 and Treg cytokine profile of the patient

The hypothesis that Helicobactermight be a risk factor for human liver diseases has arisen after the detection of Helicobacter DNA in hepatic tissue of patients with hepatobiliary diseases. Nevertheless, no explanation that justifies the presence of the bacterium in the human liver has been proposed. We evaluated the presence of Helicobacterin the liver of patients with hepatic diseases of different aetiologies. We prospectively evaluated 147 patients (106 with primary hepatic diseases and 41 with hepatic metastatic tumours) and 20 liver donors as controls. Helicobacter species were investigated in the liver by culture and specific 16S rDNA nested-polymerase chain reaction followed by sequencing. Serum and hepatic levels of representative cytokines of T regulatory cell, T helper (Th)1 and Th17 cell lineages were determined using enzyme linked immunosorbent assay. The data were evaluated using logistic models. Detection of Helicobacter pylori DNA in the liver was independently associated with hepatitis B virus/hepatitis C virus, pancreatic carcinoma and a cytokine pattern characterised by high interleukin (IL)-10, low/absent interferon-γ and decreased IL-17A concentrations (p < 10-3). The bacterial DNA was never detected in the liver of patients with alcoholic cirrhosis and autoimmune hepatitis that are associated with Th1/Th17 polarisation. H. pylori may be observed in the liver of patients with certain hepatic and pancreatic diseases, but this might depend on the patient cytokine profile.