Maximal Respiratory Pressure Reference Equations in Healthy Adults and Cut-off Points for Defining Respiratory Muscle...

Area of Science:

• Pulmonary Physiology
• Respiratory Medicine
• Clinical Diagnostics

Background:

• Maximal inspiratory and expiratory pressures (PImax/PEmax) are crucial for assessing respiratory muscle strength.
• Current reference equations lack clear cut-off points for diagnosing respiratory muscle weakness.
• Establishing reliable reference values is essential for accurate clinical interpretation.

Purpose of the Study:

• To develop sex-specific reference equations for PImax/PEmax in healthy adults.
• To determine objective cut-off points for identifying respiratory muscle weakness.
• To provide a standardized tool for evaluating respiratory muscle function.

Main Methods:

• A multicentre cross-sectional study involving 610 healthy non-smoking adults (aged 18-80 years) across 14 Spanish centers.
• Standardized assessment of PImax/PEmax using uniform methodology.
• Multiple linear regression analysis to derive reference equations and T-scores to establish cut-off points for weakness.

Main Results:

• Sex-specific reference equations for PImax/PEmax were established, incorporating body mass index and age.
• Cut-off points for respiratory muscle weakness were defined using T-scores (≥2.5 SD below peak mean values).
• Specific cut-off values were determined: PImax (females: 62 cmH2O, males: 83 cmH2O) and PEmax (females: 81 cmH2O, males: 109 cmH2O).

Conclusions:

• The study provides the largest European dataset to date for PImax/PEmax reference values, using uniform methodology.
• These new reference values and cut-off points facilitate the identification of respiratory muscle weakness in males and females.
• The findings will improve the diagnosis of respiratory muscle weakness and inform decisions regarding interventions to enhance respiratory muscle function.