Lung function and six-minute walk test performance in individuals with sickle cell disease

Abstract

BackgroundSickle Cell Disease (SCD), which is characterized by a mutation in the gene encoding beta hemoglobin, causes bodily dysfunctions such as impaired pulmonary function and reduced functional capacity. ObjectiveTo assess changes in pulmonary function and functional capacity in patients with SCD and to identify the relationships between these variables.MethodWe evaluated sociodemographic, anthropometric, lung function (spirometry), respiratory (manovacuometer), peripheral muscle strength (Handgrip strength - HS) and functional capacity (i.e., the six-minute walk test) parameters in 21 individuals with SCD (average age of 29±6 years). Shapiro-Wilk, paired Student's, Wilcoxon, Pearson and Spearman correlation tests were used for statistical analyses, and the significance threshold was set at p<0.05. ResultsA total of 47.6% of the study subjects exhibited an altered ventilation pattern, 42.8% had a restrictive ventilatory pattern (RVP) and 4.8% exhibited a mixed ventilatory pattern (MVP). The observed maximal inspiratory pressure (MIP) values were below the predicted values for women (64 cmH2O), and the maximum expiratory pressure (MEP) values, HS values and distance walked during the 6MWT were below the predicted values for both men (103 cmH2O, 39 Kgf and 447 m, respectively) and women (64 cmH2O; 27 Kgf; 405 m, respectively). Positive correlations were observed between maximum voluntary ventilation (MVV) and MEP (r=0.4; p=0.046); MVV and BMI (r=0.6; p=0.003); and between HS and MIP (r=0.7; p=0.001), MEP (r=0.6; p=0.002), MVV (r=0.5; p=0.015), distance walked in the 6MWT (r=0.4; p=0.038) and BMI (r=0.6; p=0.004). ConclusionsSCD promoted changes in lung function and functional capacity, including RVPs and a reduction in the distance walked in the 6MWT when compared to the predictions. In addition, significant correlations between the variables were observed.

Relationship between ventilation heterogeneity and exercise intolerance in adults with sickle cell anemia

“…Our results were in agreement with those of other investigators, who also noted a decrease in the 6MWD in patients with SCA (4,8). Some mechanisms have been implicated in the poor performance of patients with SCA during the 6MWT, including a low Hb level, deterioration of pulmonary function, low red blood cell deformity, presence of ACS or silent infarction, and high TRV (4,17,18).…”

Physical activity level and performance in the six-minute walk test of children and adolescents with sickle cell anemia

“…In addition, the average 6MWD in the group with SCA was numerically lower than the control group, albeit without statistical significance. In a recent study, adults with SCA had 6MWD below the value expected for the 6MWT 23 . Although there was no statistically significant difference in the means of 6MWD between the patients and controls in this study, it was observed that the perceived effort measured by the Borg scale was higher in patients with SCA.…”

Efeito Do Treinamento Muscular Inspiratório Na Função Pulmonar E Estado Funcional De Um Paciente Com Anemia Falciforme: Relato De Caso

“…A força muscular inspiratória reduzida semelhante a apresentada pelo paciente deste relato de caso, já tinha sido evidenciado em um estudo de Ohara e outros, (8) em que mulheres com AF apresentaram valores de PI máx abaixo do previsto no grupo avaliado, justificando assim a realização de TMI para ganho de força e endurance da musculatura inspiratória para este grupo de indivíduos [8][9] . Nesse relato de caso, o indivíduo apresentava um valor de força de aproximadamente 40% do valor predito para equação brasileira de referência, (10) o que confirma a presença de fraqueza muscular inspiratória.…”