In restrictive lung disease, the FEV1/FVC ratio is typically:

• A. Decreased
• B. Normal or increased
• C. Highly variable
• D. Not evaluable

Answer: (B)

In restrictive lung disease, overall lung volumes are reduced due to limited expansion or chest wall/neuromuscular constraints. Because FEV1 and FVC both decline, they do so in roughly parallel fashion, so the portion of the air expelled in the first second relative to the total expelled remains about the same or even higher. This keeps the FEV1/FVC ratio normal or increased. It’s a contrast to obstructive disease, where airway narrowing lowers the ratio because FEV1 falls disproportionately compared with FVC. So the typical pattern in restriction is a normal or elevated ratio, even though lung volumes are reduced.