Soroprevalência e fatores associados a infecções crônicas entre idosos residentes na comunidade / Seroprevalence and factors associated with chronic infections among community-dwelling elderly individuals

Resumo Infecções crônicas podem contribuir com o processo de envelhecimento, mas isso ainda é pouco explorado na América Latina. O objetivo foi avaliar a prevalência e os fatores associados ao citomegalovírus (CMV), Herpes simples 1 (HSV-1), Chlamydia pneumoniae e Helicobacter pylori entre idosos. Participaram 1.320 indivíduos da linha de base da Coorte de Idosos de Bambuí. Foram avaliados anticorpos (IgG) para as infecções e variáveis exploratórias (sociodemográficas, comportamentos em saúde e condições de saúde). Utilizaram-se modelos de regressão de Poisson com variância robusta. A prevalência foi de 99,4% para CMV, 96,7% para HSV-1, 56,0% para C. pneumoniae e 70,5% para H. pylori. Os mais velhos, mulheres, fumantes, diabéticos, incapazes e com maiores níveis de IL-6 tinham maior prevalência de CMV. HSV-1 foi menos frequente entre as mulheres. Infecção por C. pneumoniae foi maior entre os mais velhos e diabéticos; e menor entre mulheres e os menos escolarizados. H. pylori foi menos frequente entre as mulheres e naqueles com maiores níveis de IL-1β, mas mais comuns entre os fumantes. Os achados mostram elevada prevalência de infecções crônicas e diferentes perfis epidemiológicos para cada patógeno, permitindo a detecção de grupos vulneráveis a essas infecções.

Abstract Chronic infections can contribute to the aging process, but this issue is less studied in Latin America. The aim was to assess the prevalence and factors associated with cytomegalovirus (CMV), Herpes Simplex 1 (HSV-1), Chlamydia pneumoniae and Helicobacter pylori among the elderly. A total of 1,320 individuals participated from the baseline of the Elderly Cohort of Bambuí. IgG antibodies against infections and explanatory variables (sociodemographic factors, health behaviors and health conditions) were evaluated. Poisson regression models with robust variance were used. Seroprevalence rates were 99.4% for CMV, 96.7% for HSV-1, 56% for C. pneumoniae and 70.5% for H. pylori. Elderly men, women, smokers, diabetics, the disabled and those with high levels of IL-6 had a higher prevalence of CMV. HSV-1 was less frequent among women. The prevalence of C. pneumoniae was higher at ages >75 and among diabetics; it was lower among women and individuals with less schooling. H. pylori was less frequent among women and those with detectable levels of IL-1β, but more common among smokers. The findings show a high prevalence of chronic infection and a different epidemiologic profile for each pathogen, making it possible to detect groups that are vulnerable to these infections.

Inflammatory markers and occurrence of falls: Bambuí Cohort Study of Aging / Marcadores inflamatórios e ocorrência de quedas: coorte de idosos de Bambuí

ABSTRACT OBJECTIVE Analyze whether inflammatory markers are associated with falls among older adults living in Bambuí. METHODS Study that analyzed baseline data from a Bambuí Cohort Study of Aging, involving 1,250 participants. Data about falls were collected from previous 12 months, classified as single or multiple occurrence and severity (participant seeking health services). Information about sociodemographic characteristics, health behaviors and health condition was also collected and used as confounding factors. The exposures of interest included interleukins (IL-1β, IL-6, IL-8, IL-10, IL-12), tumor necrosis factor (TNF), ultra-sensitive C-reactive protein (us-CRP) and chemokines (CXCL9, CCL5, CCL10, MCP1). Data were processed through logistic regression, obtaining odds ratio and 95% confidence interval (95%CI). RESULTS The prevalence of falls was 27.1%; 40.1% of the older adults reported multiple falls and 33.3% sought health services. After adjustments, the following elevated levels were associated with falls: us-CRP (OR = 1.46, 95%CI 1.04-2.03), CCL5 (OR = 1.38, 95%CI 1.01-1.90) and CXCL9 (OR = 1.43, 95%CI 1.02-2.02). An association was observed between the number of elevated markers and the occurrence of falls: two (OR = 1.47, 95%CI 1.02-2.12) and three (OR = 2.08, 95%CI 1.12-3.87) elevated biomarkers indicated fall probability of 32.0% and 39.4%, respectively. CONCLUSIONS Elevated levels of us-CRP, CCL5 and CXCL9, which were associated with falls, may contribute to a proper understanding of the mechanism associated with the occurrence of falls among older people.

RESUMO OBJETIVO Analisar se marcadores inflamatórios estão associados a quedas em idosos vivendo na comunidade. MÉTODOS Estudo da coorte de idosos de Bambuí, envolvendo 1.250 participantes da linha de base do projeto. Foram coletadas informações sobre quedas nos últimos 12 meses, classificadas quanto à ocorrência (única ou múltipla) e gravidade (procura por serviços de saúde). O inquérito também continha informações a respeito das características sociodemográficas, comportamentais e condições de saúde, as quais foram utilizadas como fatores de confusão. As exposições pesquisadas incluíram: interleucinas (IL-1β, IL-6, IL-8, IL-10 e IL-12), fator de necrose tumoral (TNF), proteína C reativa ultrassensível (PCRus) e quimiocinas (CXCL9, CCL5, CCL10 e MCP1). O tratamento dos dados foi realizado por meio de regressão logística, obtendo-se odds ratio e intervalo de 95% de confiança (IC95%). RESULTADOS A prevalência de queda foi 27,1%; 40,1% dos idosos relataram quedas múltiplas e 33,3% procuraram serviços de saúde. Após ajustes, permaneceram associados às quedas os níveis elevados de PCRus (OR = 1,46; IC95% 1,04-2,03), CCL5 (OR = 1,38; IC95% 1,01-1,90) e CXCL9 (OR = 1,43; IC95% 1,02-2,02). Houve associação entre o número de marcadores elevados e a ocorrência de quedas: dois (OR = 1,47; IC95% 1,02-2,12) e três (OR = 2,08; IC95% 1,12-3,87) biomarcadores aumentados predisseram probabilidades de quedas iguais a 32,0% e 39,4%, respectivamente. CONCLUSÕES Os níveis elevados de PCRus, CCL5 e CXCL9, que estiveram associados a quedas, podem contribuir para o adequado entendimento do mecanismo associado à ocorrência desse evento em idosos.

Associação entre síndrome metabólica e marcadores inflamatórios em idosos residentes na comunidade / Asociación entre síndrome metabólico y marcadores inflamatorios en ancianos residentes en comunidades / Association of metabolic syndrome with inflammatory markers in a sample of community-dwelling older adults

O objetivo do trabalho foi identificar os pontos de corte dos marcadores inflamatórios que melhor discriminassem a ocorrência da síndrome metabólica entre idosos residentes na comunidade. Foram utilizados os dados da linha de base da coorte de idosos conduzida na cidade de Bambuí, Minas Gerais, Brasil. A exposição de interesse foi a presença da síndrome metabólica, definida pelo critério Adult Treatment Panel III, e os desfechos incluíram os seguintes marcadores inflamatórios: citocinas (IL-1β, IL-6, IL-10, IL-12 e TNF), quimiocinas (CXCL8, CXCL9, CCL2, CXCL10 e CCL5) e proteína C-reativa (PCR). A definição dos pontos de corte dos marcadores inflamatórios foi baseada no método Classification and Regression Tree (CART). As associações entre esses marcadores e a síndrome metabólica foram estimadas por modelos de regressão logística, obtendo-se odds ratio e intervalos de 95% de confiança (IC95%), considerando o ajustamento por fatores de confusão. A prevalência da síndrome metabólica foi de 49,1%, e os níveis de IL-1β, IL-12 e TNF não se mostraram associados a essa exposição. Após ajustamento, a presença da síndrome metabólica foi associada a maiores valores de IL-6 e PCR e a menores valores de CXCL8 e CCL5. Associações significativas ainda foram observadas com níveis séricos intermediários de CXCL9 e CXCL10. Além disso, a combinação dos marcadores apresentou associação significativa e consistente com a síndrome metabólica. Além de demonstrar associação entre síndrome metabólica e uma ampla gama de biomarcadores, alguns ainda não descritos na literatura, os resultados ressaltam que essa associação ocorre em níveis muito inferiores aos já demonstrados, sugerindo que a síndrome metabólica desempenha importante papel no perfil inflamatório dos idosos.

El objetivo del trabajo fue identificar los puntos de corte de los marcadores inflamatorios que mejor discriminaran la ocurrencia del síndrome metabólico entre ancianos residentes en comunidades. Se utilizaron datos de referencia de una cohorte de ancianos, realizada en la ciudad de Bambuí, Minas Gerais, Brasil. La exposición de interés fue la presencia del síndrome metabólico, definida por el criterio Adult Treatment Panel III, y los desenlaces incluyeron los siguientes marcadores inflamatorios: citocinas (IL-1β, IL-6, IL-10, IL-12 e TNF), quimiocinas (CXCL8, CXCL9, CCL2, CXCL10 y CCL5) y proteína C-reactiva (PCR). La definición de los puntos de corte de los marcadores inflamatorios se basó en el método Classification and Regression Tree (CART). Las asociaciones entre esos marcadores y el síndrome metabólico se estimaron mediante modelos de regresión logística, obteniéndose odds ratio e intervalos con 95% de confianza, considerando el ajuste por factores de confusión. La prevalencia del síndrome metabólico fue de 49,1%, y los niveles de IL-1β, IL12 y TNF no se mostraron asociados a esa exposición. Tras el ajuste, la presencia del síndrome metabólico se asoció a mayores valores de IL-6 y PCR y a menores valores de CXCL8 y CCL5. Las asociaciones significativas se observaron incluso con niveles séricos intermedios de CXCL9 y CXCL10. Asimismo, la combinación de los marcadores presentó una asociación significativa y consistente con el síndrome metabólico. Además de demostrar asociación entre el síndrome metabólico y una amplia gama de biomarcadores, algunos todavía no descritos en la literatura, los resultados resaltan que esa asociación ocurre en niveles muy inferiores a los ya demostrados, sugiriendo que el síndrome metabólico desempeña un importante papel en el perfil inflamatorio de los ancianos.

The study aimed to identify the cutoff points for inflammatory markers that best discriminate the occurrence of metabolic syndrome in community-dwelling older adults. Baseline data were used from the elderly cohort in the city of Bambuí, Minas Gerais State, Brazil. The target exposure was presence of metabolic syndrome, defined according to the Adult Treatment Panel III criterion, and the outcomes included the following inflammatory markers: cytokines (IL-1β, IL-6, IL-10, IL-12 e TNF), chemokines (CXCL8, CXCL9, CCL2, CXCL10, and CCL5), and C-reactive protein (CRP). Definition of the cutoff points for the inflammatory markers was based on the Classification and Regression Tree (CART) method. The associations between these markers and metabolic syndrome were estimated by logistic regression models, obtaining odds ratios and 95% confidence intervals, considering adjustment for confounding factors. Prevalence of metabolic syndrome was 49.1%, and IL-1β, IL-12, and TNF levels were not associated statistically with this exposure. After adjustment, presence of metabolic syndrome was associated with higher IL-6 and CRP levels and lower CXCL8 and CCL5. Significant associations were also observed with intermediate serum CXCL9 and CXCL10 levels. The combination of markers also showed a significant and consistent association with metabolic syndrome. In addition to demonstrating an association between metabolic syndrome and a wide range of biomarkers (some not previously described in the literature), the results highlight that this association occurs at much lower levels than previously demonstrated, suggesting that metabolic syndrome plays an important role in the inflammatory profile of the older adults.

Distinct cytokine profiles of circulating mononuclear cells stimulated with Staphylococcus aureus enterotoxin A in vitro during early and late episodes of chronic osteomyelitis

We investigated the cytokine profile of peripheral mononuclear cells from chronic osteomyelitis (OST) patients following in vitro stimulation with staphylococcal enterotoxin A (SEA). We demonstrate that stimulation with SEA induced prominent lymphocyte proliferation and high levels of tumour necrosis factor (TNF)-α, interleukin (IL)-4 and IL-10 secretion in both OST and non-infected individuals (NI). Even though stimulation with SEA had no impact on IL-6 production in either patient group, the baseline level of IL-6 production by cells from OST patients was always significantly less than that produced by cells from NI. After classifying the osteomyelitic episodes based on the time after the last reactivation event as "early" (1-4 months) or "late" osteomyelitis (5-12 months), we found that increased levels of TNF-α and IL-4 in combination with decreased levels of IL-6 were observed in the early episodes. By contrast, increased levels of IL-10, IL-2 and IL-6 were hallmarks of late episodes. Our data demonstrate that early osteomyelitic episodes are accompanied by an increased frequency of "high producers" of TNF-α and IL-4, whereas late events are characterised by increased frequencies of "high producers" of IL-10, IL-6 and IL-2. These findings demonstrate the distinct cytokine profiles in chronic osteomyelitis, with a distinct regulation of IL-6 production during early and late episodes.

Innate immunity and regulatory T-cells in human Chagas disease: what must be understood?

There is a general consensus that during chronic Trypanosoma cruzi infection, the host immune system induces complex processes to ensure the control of parasite growth while preserving the potential to mount and maintain a life-long controlled humoral and cellular immune response against the invading pathogen. This review summarises evidence in an attempt to elucidate "what must be understood" to further clarify the role of innate immunity in the development/maintenance of clinical Chagas disease and the impact of etiological treatment on host immunity, highlighting the contributions of the innate immunity and regulatory T (Treg) cells. Recently, increasing focus on innate immunity suggest that chronic T. cruzi infection may cause morbidity when innate effector functions, or the down-regulation of adaptive regulatory mechanisms are lacking. In this context, stable asymptomatic host-parasite interactions seem to be influenced by the effector/regulatory balance with the participation of macrophages, natural killer (NK) and CD8+ T cells in parallel with the establishment of regulatory mechanisms mediated by NKT and Treg cells. Moreover, a balanced innate immune activation state, apart from Treg cells, may play a role in controlling the adverse events triggered by the massive antigen release induced by trypanosomicidal agents during Chagas disease etiological treatment.

High expression of co-stimulatory and adhesion molecules are observed on eosinophils during human Schistosoma mansoni infection

Herein we have focused attention on major phenotypic features of peripheral blood eosinophils from chronic Schistosoma mansoni-infected patients. For this purpose, detailed immunophenotypic profiles of a range of cell surface markers were performed, including activation markers (CD23/CD69/CD25/HLA-DR), co-stimulatory molecules (CD28/CD80/CD86), chemokine receptors (CXCR1/CXCR2/CCR3/CCR5) besides L-selectin-CD62L and adhesion molecules (CD18/CD54). Our major findings pointed out increased frequency of CD23+-cells, besides decreased percentages of CD69+-eosinophils, suggesting a chronic activation status with low frequency of early activated eosinophils in chronic S. mansoni-infected patients (INT) in comparison to non-infected individuals (NI). Moreover, a dichotomic expression of beta-chemokine receptors was observed during human schistosomiasis mansoni with higher CCR5 and lower levels of CCR3 observed between groups. Enhanced expression of co-stimulatory receptors (CD28/CD86) and adhesion molecules (CD54/CD18), besides striking lower frequency of L-selectin+ were reported for eosinophils from INT group as compared to NI. Interestingly, the frequency of CD62L+-eosinophils and a range of cell activation related molecules pointed out an opposite pattern of association in NI and INT, where only INT patients that display lower frequency of CD62L+-eosinophils (first CD62L tertile) kept the unusual relationship between the expression of L-selectin and the CD23 activation marker. These findings suggest that distinct dynamic of activation markers expressed by eosinophils may occur during chronic S. mansoni infection.