Changes of pulmonary function and its relation with severity of myasthenia in patients with myasthenia gravis
10.3760/cma.j.issn.1671-8925.2010.05.019
- VernacularTitle:重症肌无力患者肺功能改变及其与临床肌无力严重度的相关分析
- Author:
Yi ZHOU
1
;
Wei-Guo ZHAO
;
Bing CHEN
;
Yu LIU
Author Information
1. 解放军第309医院
- Keywords:
Myasthenia gravis;
Muscle strength;
Muscles-endurance;
Severity of muscle weakness
- From:
Chinese Journal of Neuromedicine
2010;9(5):517-520
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the relation between the changes of respiratory muscle strength and both the changes of pulmonary function and the severity of myasthenia in patients with myasthenia gravis (MG). Methods We measured the respiratory muscle strength (maximal inspiratory pressure [PIM], maximal expiratory pressure [PEM] and P0.1) and pulmonary function (vital capacity [VC],maximal voluntary ventilation [MVV], peak flow [PF], R5 and R20) of 50 patients with type Ⅱ MG (group B), 16 patients with type Ⅰ MG (group A) and 30 healthy controls (group C). In addition, we analyzed the correlation between the pulmonary function and both the changes of respiratory muscle strength and the severity of myasthenia in group B. Results Comparison with group C, patients in group A had significantly decreased level of MW and P PIM, and statistically increased level of R20 and R5 (P<0.05);additionally, the level of VC, MW, PF, PIM and PEM, in group B decreased markedly with R20 increased markedly only as compared with that in the controls (P<0.05). Patients in group B showed significantly decreased level of PIm and PEM, and increased level of R20 and R5 as compared with the patients in group A (P<0.05). The level of PIM< PEM. MW and VC in group B was positively correlated to the absolute scores of severity of myasthenia in patients with type II MG (r=0.550, P=0.002; r=0.653, P=0.000; r=0.511,P=0.000; r=0.353, P=0.010). The level of PIM had positive correlation with the level of MW, VCand PF, so was the level of PEM. Positive correlation was also found between the level of PIM and PEM.Conclusions PatientswithtypeIMGinthe early stagemaynotmanifested ashavingmyasthenia,buthad weak strength and tolerance of respiratory muscle, thus, the level of MW, PIM,R10 and R5 might be the sensitive indexes in its early diagnosis. Changes of pulmonary function and respiratory muscle strength in patients with type Ⅱ MG were more obvious as compared with those in patients with type Ⅱ MG and these changes were positively correlated to the absolute scores of severity of myasthenia, which were consistent with the respiratory muscle strength and ventilatory function defects.
