[Influence of treatment with continuous positive airway pressure on respiratory muscle function and physical fitness in patients with obstructive sleep apnoea and overlap syndrome].

INTRODUCTION

The aim of this study was to evaluate the effect of CPAP treatment on respiratory muscle strength and exercise tolerance in patients with obstructive sleep apnoea (OSA) and overlap syndrome (OS).

MATERIAL AND

METHODS

9 patients with OSA and 9 patients with OS were studied. Respiratory muscle assessment, 6 minute walking distance (6MWD) and cycloergometry exercise test were performed before and after six month period of CPAP treatment.

RESULTS

In OSA group exercise tolerance did not change after the treatment. Mean 6MWD was 571.8 +/- 76.6 m before and 554.0 +/- 125.5 m after treatment, mean W(max) was 142 +/- 41 W before and 139 +/- 38 W after treatment. PI(max) in OSA group did not change significantly, 140.4 +/- 32.0 cm H(2)O before and 155.9 +/- 31.5 after treatment (p = 0.14). PE(max) improved from 170.5 +/- 49.2 cm H(2)O, to 199.9 +/- 27.6 cm H(2)O (p = 0.067). Handgrip force in OSA group improved from 50.5 +/- 16.5 kg to 61.0 +/- 17.0 kg (left hand) (p = 0.05) and from 53.3 +/- 14.2 to 58.9 +/- 15.9 (right hand) (p < 0.05). In OS group exercise tolerance improved by 17% after CPAP treatment from W(max) = 81 +/- 33 W before to 95 +/- 38 W after. Mean 6MWD was at the same level before (504 +/- 144 m) and after treatment (492 +/- 108 m). PI(max) in OS group improved from 89.2 +/- 35.7 cm H(2)O to 106.3 +/- 31.4 cm H(2)O (p < 0.05). PE(max) in OS group did not change significantly, 159.9 +/- 45.8 cm H(2)O before and 184.2 +/- 45.0 cm H(2)O after treatment (NS). Handgrip force in OS group improved from 38.1 +/- 15.9 kg to 46.9 +/- 11.1 kg (left hand) (p < 0.05) and did not change in right hand (44.5 +/- 17.7 kg vs. 47.9 +/- 10.4 kg) (NS). Data analysis of the whole group (18 pts) showed clear tendency to improve strength of respiratory muscles in patients treated with CPAP. Mean PI(max) improved from 123 to 133 cm H(2)O (p = 0.006) and PE(max) improved from 168.1 to 192 cm H(2)O (p = 0.02).

CONCLUSIONS

CPAP treatment improved strentgh of respiratory and skeletal muscles in patients with OSA and OS and improved exercise tolerance in patients with OS.