Vascular function in asthmatic children and adolescents.

BACKGROUND: Epidemiological studies have demonstrated an increased incidence of cardiovascular events in patients with bronchial asthma, but little is known about the relationship between asthma and vascular function. The purpose of this study was to evaluate endothelial function and arterial stiffness in children and adolescents with asthma. METHODS: A cross-sectional controlled study was designed. Measurements of endothelial function and arterial stiffness in asthmatic (13.6 ± 0.6 years) and control groups (14.9 ± 0.7 years) were taken by the non-invasive peripheral arterial tonometry (EndoPAT2000) determined by using the natural logarithm of the reactive hyperemia index (LnRHI) and the augmentation index (AIx@75%), respectively. Patients with asthma were also administered two questionnaires to evaluate asthma control and quality of life. Exercise functional capacity was evaluated using the Shuttle Walking Test (SWT). Only male participants were included in the present study. RESULTS: LnRHI and the walked distance during the SWT were similar between groups (p = 0.23 and p = 0.50, respectively). AIx@75% was significantly higher in the asthmatic group (-7.75 ± 1.7) compared to the control group (-15.25 ± 1.8), p < 0.04. In the control group, the LnRHI correlated positively with baseline systolic blood pressure (r = 0.53, p = 0.02) and mean arterial pressure (r = 0.50, p = 0.03), age (r = 0.61, p = 0.007), weight (r = 0.63, p = 0.004) and height (r = 0.56, p = 0.015). Besides that LnRHI correlated with FVC (r = 0.69, p = 0.002), FEV1, (r = 0.53, p = 0.03) and negatively with Tiffeneau index (FEV1/FVC%, r = -0.49 p = 0.04). The LnRHI of the asthmatic group did not correlate with the different variables evaluated. CONCLUSION: The increased AIx@75% without changes in LnRHI in asthmatic patients could mean that an early detection of vascular impairment may precede endothelial dysfunction, and that different mechanisms may contribute to the pathogenesis and progression of cardiovascular events in this population. A large prospective and randomized controlled study should be done to evaluate the physiopathological mechanisms underlying the association between arterial stiffness and asthma.

Comparação dos valores medidos e previstos de pressões respiratórias máximas em escolares saudáveis / Comparison of measured and predicted values for maximum respiratory pressures in healthy students / Comparación de los valores medidos y previstos de presiones respiratorias máximas en escolares sanos

A Força Muscular Respiratória é uma ferramenta capaz de diagnosticar diferentes desordens. As equações de referência até hoje descritas consideram diferentes populações e metodologias. Entretanto, não há consenso quanto a qual equação é ideal para se utilizar. O objetivo deste estudo foi comparar e correlacionar valores medidos de pressões respiratórias máximas com aqueles previstos por equações descritas na literatura. A amostra foi de 90 indivíduos saudáveis de 6 a 12 anos. Foram realizadas antropometria, espirometria e manovacuometria. A comparação dos valores medidos e previstos diferiu significativamente, apresentando pressão inspiratória máxima (PImáx) média (80,65±26,78), no sexo masculino, maior que a prevista por Wilson et al. (67,40±5,65; p<0,001) e Schmidt et al. (70,69±21,70; p<0,05). Pressão expiratória máxima (PEmáx) masculina média (84,35±23,16) foi menor que a prevista por Domènech-Clar et al. (92,25±16,90; p<0,01) e maior que a prevista por Schmidt et al. (72,78±13,62; p<0,001). Pressão inspiratória máxima feminina média (76,14±26,08) foi maior que a prevista por Wilson et al. (57,96±6,04; p<0,001), Schmidt et al. (68,54±7,08; p<0,01) e Domènech-Clar et al. (67,61±11,17; p<0,01). Pressão expiratória máxima feminina média (74,55±20,05) foi maior que a prevista por Wilson et al. (66,65±9,55; p<0,001) e menor que a prevista por Domènech-Clar et al. (81,16±14,37; p<0,01). As correlações entre valores medidos e previstos foram de baixa a média magnitude (variação entre r=0,1 e 0,5), sendo significativas para o sexo masculino quando a PImáx foi correlacionada à prevista por Wilson et al. (p<0,01) e Domènech-Clar et al. (p<0,05). Já para o sexo feminino, ambas as correlações foram significativas (PImáx p<0,01; PEmáx p<0,05). Concluiu-se que as equações não conseguiram predizer os valores de pressões respiratórias máximas, reforçando a necessidade de novas equações de força muscular respiratória...

Respiratory Muscle Strength is an important tool to diagnose different disorders. Reference equations considered different populations and methodologies. However, there is no agreement on what is the ideal equation to use. The aim of this study was to compare and correlate the measured values of maximal respiratory pressures with those demonstrated by equations described in literature. The sample consisted of 90 healthy individuals aged from 6 to 12 years old. Anthropometric, spirometric and manometric measurements were performed. The comparison between measured and predicted values was significantly different, showing the mean male maximum inspiratory pressure (maxIP) (80.65±26.78) to be higher than that predicted by Wilson et al. (67.40±5.65, p<0.001) and Schmidt et al. (70.69±21.70, p<0.05). The mean male maximum expiratory pressure (maxEP) (84.35±23.16) was lower than the one predicted by Domènech-Clar et al. (92.25±16.90, p<0.01) and higher than the one predicted by Schmidt et al. (72.78±13.62 p<0.001). The mean of female individuals' maxIP (76.14±26.08) was higher than that predicted by Wilson et al. (57.96±6.04, p<0.001), Schmidt et al. (68.54±7.08, p<0.01), and Domènech-Clar et al. (67.61±11.17, p<0.01). The mean female maxEP (74.55±20.05) was higher than the ones predicted by Wilson et al. (66.65±9.55, p<0.001) and lower than the one predicted by Domènech-Clar et al. (81.16±14.37, p<0.01). The correlations between measured and predicted values were from low to medium magnitude (range r=0.1 to 0.5) being significant for males when maxIP was correlated with that predicted by Wilson et al. (p<0.01) and Domènech-Clar et al. (p<0.05). For females, both correlations were significant (maxIP p<0.01; maxEP p<0.05). It was concluded that the equations failed to predict the values of maximum respiratory pressures, reinforcing the need for new equations of respiratory muscle strength...

La Fuerza Muscular Respiratoria es una herramienta capaz de diagnosticar diferentes desórdenes. Las ecuaciones de referencia hasta hoy descritas consideran diferentes poblaciones y metodologías. Entre tanto, no hay consenso en cuanto a que ecuación es ideal para utilizar. El objetivo de este estudio fue comparar y correlacionar valores medidos de presiones respiratorias máximas con aquellos previstos por las ecuaciones descritas en la literatura. La muestra fue de 90 individuos sanos de 6 a 12 años. Fueron realizadas antropometría, espirometría y manovacuometría. La comparación de los valores medidos y previstos difirió significativamente, presentando presión inspiratoria máxima (PImáx) media (80,65±26,78) , en el sexo masculino, mayor que la prevista por Wilson et al. (67,40±5,65; p<0,001) y Schmidt et al. (70,69±21,70; p<0,05). Presión expiratoria máxima (PEmáx) masculina media (84,35±23,16) menor que la prevista por Domènech-Clar et al. (92,25±16,90; p<0,01) y mayor que Schmidt et al. (72,78±13,62; p<0,001). Presión inspiratoria máxima femenina media (76,14±26,08) mayor que la prevista por Wilson et al. (57,96±6,04; p<0,001), Schmidt et al. (68,54±7,08; p<0,01) y Domènech-Clar et al. (67,61±11,17; p<0,01). Presión expiratoria máxima femenina media (74,55±20,05) mayor que la prevista por Wilson et al. (66,65±9,55; p<0,001) y menor que Domènech-Clar et al. (81,16±14,37; p<0,01). Las correlaciones entre valores medidos y previstos fueron de baja a media magnitud (variación entre r=0,1 y 0,5) siendo significativas para el sexo masculino cuando la PImáx fue correlacionada a la prevista por Wilson et al. (p<0,01) y Domènech-Clar et al. (p<0,05). Para el sexo femenino, ambas correlaciones fueron significativas (PImáx p<0,01; PEmáx p<0,05). Se concluyó que las ecuaciones no consiguieron predecir los valores de presiones respiratorias máximas, reforzando la necesidad de nuevas ecuaciones de fuerza muscular respiratoria...