Which pattern is characterized by a reduced FEV1 with a normal or sometimes increased FEV1/FVC ratio due to reduced lung volumes?

Which pattern is characterized by a reduced FEV1 with a normal or sometimes increased FEV1/FVC ratio due to reduced lung volumes?

• A. Obstructive lung disease pattern
• B. Normal aging changes
• C. Restrictive lung disease pattern
• D. Mixed ventilation pattern

Answer: (C)

Restrictive lung disease pattern is defined by reduced lung volumes. When the lungs or chest wall are restricted, the total volume the lungs can hold (TLC) decreases. Spirometry reflects this as a fall in both FEV1 and FVC, but the FEV1/FVC ratio stays normal or may even increase because the decline is due to smaller lung volumes rather than a disproportionate loss of expiratory flow. That’s why a reduced FEV1 with a normal or higher FEV1/FVC ratio points to restriction rather than obstruction, which typically lowers the ratio. This pattern can arise from conditions that stiffen the lungs or chest wall, or from neuromuscular problems that limit lung expansion.

Restrictive lung disease pattern is defined by reduced lung volumes. When the lungs or chest wall are restricted, the total volume the lungs can hold (TLC) decreases. Spirometry reflects this as a fall in both FEV1 and FVC, but the FEV1/FVC ratio stays normal or may even increase because the decline is due to smaller lung volumes rather than a disproportionate loss of expiratory flow. That’s why a reduced FEV1 with a normal or higher FEV1/FVC ratio points to restriction rather than obstruction, which typically lowers the ratio. This pattern can arise from conditions that stiffen the lungs or chest wall, or from neuromuscular problems that limit lung expansion.