Effects of home-based inspiratory muscle training on sickle cell disease (SCD) patients

Abstract

Introduction Inspiratory muscle training (IMT) has been shown to be an efficient method of improving exercise tolerance and inspiratory and expiratory muscle strength in several diseases. The effects of IMT on patients with sickle cell anemia (SCD) are relatively unknown. Our study aimed to evaluate the effects of IMT on adult SCD patients, regarding respiratory muscle strength (RMS) variables, lung function, exercise tolerance, blood lactation concentration, limitation imposed by dyspnea during daily activities and impact of fatigue on the quality of life. Methods This was a randomized single-blind study, with an IMT design comprising true load (TG) and sham load (SG) groups. Initial assessment included spirometry, volumetric capnography (VCap) and measurement of RMS by maximal inspiratory and expiratory pressure (PImax and PEmax). The Medical Research Council dyspnea scale and modified fatigue impact scale were also applied and blood lactate concentration was measured before and after the 6-minute walk test. After this initial assessment, the patient used the IMT device at home daily, returning every 6 weeks for RMS reassessment. Both groups used the same device and were unaware of which group they were in. After a period totaling 18 weeks, patients underwent the final evaluation, as initially performed. Results Twenty-five patients in total participated until the end of the study (median age 42 years). There were no significant differences between TG and SG based on age, sex, body mass index or severity of genotype. At the end of the training, both groups showed a significant increase in PEmax and PImax, improvement in Vcap and in exercise tolerance and dyspnea reduction while performing daily life activities. The same was observed in patients grouped according to disease severity (HbSS and HbSβ 0 vs HbSC and HbSβ + ), without differences between groups. Conclusion Home-based inspiratory muscle training benefits outpatients with SCD, including the sham load group. Trial registration http://www.ensaiosclinicos.gov.br ; registration number: RBR-6g8n92.

Diaphragm excursion correlates with performance and ventilation on the 6‐min walk test in children with sickle cell disease

“…These issues create many challenges for exercise interventions because of the implications for strength training. In a study on inspiratory muscle training in adults with SCD, where the treatment group received training with an inspiratory load progressing from 30% to 60% of MIP while the control group received a sham load without resistance, both groups had improved respiratory muscle strength, lung function, and 6MWT distance at 18 weeks 36 . Thickness and excursion were not measured in that study, so whether functional improvements in either group resulted from hypertrophy or more effective respiratory movements is not known.…”