Reference Range of Respiratory Muscle Strength and Its Clinical Application in Amyotrophic Lateral Sclerosis: A Single-Center Study

Abstract

Background and PurposeEvaluating respiratory function is important in neuromuscular diseases. This study explored the reference ranges of the maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and sniff nasal inspiratory pressure (SNIP) in healthy adults, and applied them to amyotrophic lateral sclerosis (ALS) patients.MethodsMIP, MEP, and SNIP were measured in 67 healthy volunteers aged from 21 to 82 years. Reference ranges were evaluated by multivariate regression analysis using the generalized additive modeling of location, scale, and shape method. Thirty-six ALS patients were reviewed retrospectively, and abnormal values of MIP, MEP, and SNIP were determined according to the reference ranges.ResultsMIP, MEP, and SNIP were abnormal in 57.1%, 51.4%, and 25.7% of the ALS patients, respectively. MIP and SNIP were significantly correlated with the degree of restrictive pattern and respiratory symptoms. The ALS Functional Rating Scale-Revised score was correlated with SNIP.ConclusionsThis study has provided the reference range of respiratory muscle strength in healthy adults. This range is suitable for evaluating respiratory function in ALS patients.

Assessment of Respiratory Muscle Weakness in Subjects With Neuromuscular Disease

“…These findings may be due to the curvilinear relationship between FVC and respiratory muscle strength, which results in substantial weakness while FVC is within its normal range. 30,35 We also observed significant moderate correlations between FEV 1 and TLC (measured in liters) and some maximum respiratory pressures, in agreement with results that show statistically significant correlations between maximum respiratory pressures and FEV 1 (%) and FVC (%) in patients with amyotrophic lateral sclerosis, 36 and between P Imax and P Emax , and FEV 1 (L), FVC (L), and TLC (L) in patients with COPD. 37 In contrast, a study of subjects with motor neuron disease found no correlations of P Imax and P Emax with P aCO 2 , although the sniff nasal inspiratory pressure was negatively correlated with P aCO 2 in subjects without bulbar dysfunction only.…”

Handgrip Force and Maximum Inspiratory and Expiratory Pressures in Critically Ill Patients With a Tracheostomy

“…39 The moderate correlation between MIP and MEP may explain the interaction between these 2 indicators in patients with ICU-AW. Our result does not differ greatly from the result of a study by Park et al 40 in which MIP and MEP were significantly correlated in healthy patients (r = 0.597, P < .001).…”

Associations between pulmonary function and cognitive decline in the middle-aged and older adults: evidence from the China Health and Retirement Longitudinal Study

“…We found that the baseline PEF was more likely to be inversely associated with cognitive decline in men >60 years. Previous studies have found that the rate of decline in lung function levels accelerates significantly with increasing age in older adults [49] due to age-related changes in thoracic posture and general stiffening of the ribs [50] and the aging of the airway epithelial and cartilaginous tissues. The progressive decrease in pulmonary function and the state of chronic long-term hypoxia in older adults may be the most important cause of reduced cognitive function.…”