Is it useful to perform carbon monoxide diffusion capacity and respiratory muscle function tests in patients with multiple sclerosis without disability?

Impairment of respiratory function has been described in end-stage multiple sclerosis (MS), as well as in patients with mild to severe disability. No data are available regarding the respiratory function of MS patients without disability. The objective of this study was to assess the pulmonary function, respiratory muscle strength and carbon monoxide diffusion capacity of the lungs (DL(CO)) in patients with relapsing-remitting multiple sclerosis (RRMS) without disability. Twenty-seven RRMS patients and 25 healthy control subjects were recruited. All subjects underwent clinical and neurological examination, and spirometry; lung volumes, DL(CO) and maximal respiratory pressures were measured. All subjects were rated on the Modified Fatigue Impact Scale and Fatigue Severity Scale scales. There were no significant differences in age, gender, height, weight or body mass index between the groups. The mean duration of illness in the MS group was 5.44 ± 3.74 years, and the mean Expanded Disability Status Scale was 0.62 ± 0.65. The mean values for total lung capacity, forced expiratory volume in 1 s (FEV(1)) and FEV(1) /FVC were normal in both groups. Fifteen RRMS patients exhibited a reduction in maximal expiratory pressure (MEP), but only one patient exhibited a reduction in maximal inspiratory pressure. The mean values for DL(CO) were lower in RRMS patients (P = 0.0004) than in the control group. DL(CO) was decreased in 15 (55.55%), out of 27 RRMS patients. The fatigue scale results were not correlated with pulmonary function test results DL(CO) and MEP may be impaired in RRMS patients without disability.

Carvalho SR ，Alvarenga Filho H ，Papais-Alvarenga RM ，Chacur FH ，Dias RM ... -  《-》

A combined inspiratory and expiratory muscle training program improves respiratory muscle strength and fatigue in multiple sclerosis.

To determine the effects of a short-duration, combined (inspiratory and expiratory), progressive resistance respiratory muscle training (RMT) protocol on respiratory muscle strength, fatigue, health-related quality of life, and functional performance in individuals with mild-to-moderate multiple sclerosis (MS). Quasi-experimental before-after trial. University rehabilitation research laboratory. Volunteers with MS (N=21) were divided into 2 groups: RMT (n=11; 9 women, 2 men; mean age ± SD, 50.9 ± 5.7y, mean Expanded Disability Status Scale score ± SD, 3.2 ± 1.9) and a control group that did not train (n=10; 7 women, 3 men; mean age ± SD, 56.2 ± 8.8y, mean Expanded Disability Status Scale score ± SD, 4.4 ± 2.1). Expanded Disability Status Scale scores ranged from 1 to ≤6.5. No patients withdrew from the study. Training was a 5-week combined progressive resistance RMT program, 3d/wk, 30 minutes per session. The primary outcome measures were maximal inspiratory pressure and expiratory pressure and the Modified Fatigue Impact Scale. All subjects completed secondary measures of pulmonary function, the six-minute walk test, the timed stair climb, the Multiple Sclerosis Self-Efficacy Scale, the Medical Outcomes Study 36-Item Short-Form Health Survey, and the Physical Activity Disability Scale. Maximal inspiratory pressure and expiratory pressure (mean ± SD) increased 35% ± 22% (P<.001) and 26% ± 17% (P<.001), respectively, whereas no changes were noted in the control group (12% ± 23% and -4% ± 17%, respectively). RMT improved fatigue (Modified Fatigue Impact Scale, P<.029), with no change or worsening in the control group. No changes were noted in the six-minute walk test, stair climb, Multiple Sclerosis Self-Efficacy Scale, or Physical Activity Disability Scale in the RMT group. The control group had decreases in emotional well-being and general health (Medical Outcomes Study 36-Item Short-Form Health Survey). A short-duration, combined RMT program improved inspiratory and expiratory muscle strength and reduced fatigue in patients with mild to moderate MS.

Ray AD ，Udhoji S ，Mashtare TL ，Fisher NM ... -  《-》

Pulmonary function in multiple sclerosis without any respiratory complaints.

Altintas A ，Demir T ，Ikitimur HD ，Yildirim N ... -  《CLINICAL NEUROLOGY AND NEUROSURGERY》

Correlation between trunk control, respiratory muscle strength and spirometry in patients with stroke: an observational study.

 Stroke is the main cause of chronic disability in adults, and the effect of a stroke on the respiratory system depends on the structures affected by the lesion.   To evaluate the correlation between trunk control, respiratory muscle strength and pulmonary function in individuals who suffered stroke.   Observational, quantitative and descriptive study. Twenty-three patients who had a clinical diagnosis of ischaemic or haemorrhagic stroke. The trunk control was assessed through the Trunk Impairment Scale (TIS), and the respiratory muscle strength was assessed by manovacuometry by measuring the maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP). For pulmonary function analysis, we measured forced vital capacity (FVC), forced expiratory volume in one second (FEV₁), peak expiratory flow (PEF) and the Tiffeneau index (TIFF) through spirometry.   A consistent and statistically significant correlation was found between TIS and PEF (r = 0.489, p = 0.024) and between TIS and EPmax (r = 0.517, p = 0.016). No relation was found between the other variables of pulmonary function and TIS.   This study demonstrated that there is a relation between trunk control and respiratory muscular strength, especially concerning the expiratory muscles. However, there seems to be no relation between trunk control and pulmonary function in this series of individuals who suffered stroke.

Jandt SR ，Caballero RM ，Junior LA ，Dias AS ... -  《-》

Effect of salbutamol on the measurement of single-breath diffusing capacity.

The bronchodilation and cardiovascular effects of bronchodilators may alter alveolar ventilation and perfusion distribution, which could subsequently affect single-breath diffusing capacity of the lungs for carbon monoxide (DL ,CO) measurements. The aim of this study was to investigate the effect of salbutamol on DL ,CO in subjects with and without airway obstruction and reversibility. Sixty subjects were investigated with 20 in each of the three groups: normal spirometry; irreversible obstruction; and reversible obstruction. Baseline spirometry, plethysmographic lung volumes, DL ,CO, pulse rate and arterial blood gases were measured. The same testing sequence was repeated after administration of a placebo inhaler and again after 400 μg salbutamol. Salbutamol did not affect the mean alveolar volume (VA ) (P > 0.05), transfer coefficient for carbon monoxide (DL ,CO/VA , KCO) (P > 0.05) or DL ,CO (P > 0.05) in the normal and irreversible obstruction groups. In the reversible obstruction group, salbutamol caused an increase in the mean VA compared with placebo (P < 0.001). However, the mean KCO was reduced (P < 0.001). The mean change in DL ,CO was not significant (P > 0.05). A considerable reduction in DL ,CO was found after salbutamol in four subjects in the reversible group as a result of a minor increase in VA and substantial decrease in KCO. No statistical difference in pulse rate or arterial blood gases values was detected. Salbutamol had no effect on the mean DL ,CO in any group. However, salbutamol may considerably reduce DL ,CO in some individuals with reversibility secondary to its effects on VA and KCO.

Yang J ，Stanton J ，Wang L ，Beckert L ，Frampton C ，Burton D ，Swanney MP ... -  《-》