Dados do Trabalho

Título

Effects of eight weeks of inspiratory muscle training on respiratory and clinical variations in individuals with obstructive sleep apnea: preliminary data

Introdução

Treatments for obstructive sleep apnea (OSA) aim to control apnea, hypoxemia, and associated symptoms. Continuous positive airway pressure (CPAP) remains the gold standard therapy. However, new therapeutic approaches, such as inspiratory muscle training (IMT), have been explored.

Objetivo

To evaluate the effects of 8 weeks of IMT on respiratory and clinical outcomes, as well as on inspiratory muscle strength and endurance in individuals with OSA.

Métodos

We included OSA volunteers who had low compliance to CPAP or did not adapt to this therapy, as well as those referred for non-CPAP treatments. Maximum inspiratory pressure (MIP) and maximum expiratory pressure (MEP) measurements were performed using a digital vacuum manometer, and the endurance test was conducted with Power Breath®. The 8-week inspiratory muscle training (IMT) protocol involved daily training (two sessions per day, three sets of 30 repetitions, six days per week) at 70% of MIP. Type 3 home sleep test was performed by Apnea LinkAir (ResMed®) at the beginning and at the end of the protocol. The Shapiro-Wilk test was used to assess data normality, and paired t-tests and Wilcoxon signed-rank tests were applied to analyze changes after IMT. The significance level was set at 5%.

Resultados

Thirteen participants (85% men, mean age of 51.2 ± 12.2 years, BMI of 27.7 ± 3.0 kg/m²), with a respiratory disturbance index (RDI) of 20.0 ± 17.5 events/hour completed the study. Inspiratory muscle training (IMT) significantly increased maximum inspiratory pressure (MIP) from 129±23 to 167±32 cmH₂O (p<0.001) and endurance time from 395.5 ± 139.9 to 814.5 ± 243.0 seconds (p<0.001). Regarding symptoms, participants showed improvement in complaints of respiratory arrest (p=0.031) and drowsiness (p<0.001), but no significant changes were observed for other symptoms, such as gastroesophageal reflux (69% vs 31%, p=0.063), maintenance insomnia (38% vs 0%, p=0.063), oral dryness (38% vs 7%, p=0.125), and memory deficit (54% vs 23%, p=0.125) before and after the intervention. Additionally, no significant changes were observed in RDI (p=0.32), oxyhemoglobin desaturation index (p=0.34), mean saturation (p=0.50), and time with saturation <90% (p=0.31). Minimum saturation decreased from 82 ± 6% before to 76 ± 9% after IMT (p=0.02).

Conclusões

Inspiratory muscle strength and endurance were improved after 8 weeks of IMT but promoted minimal impact on symptom improvement and did not significantly affect polygraphic variables in this population.

Palavras -chave

IMT, OSA