What is the primary physiological change in restrictive lung disease?

In restrictive lung disease, the primary physiological change is characterized by decreased lung volumes. This condition involves a reduction in the ability of the lungs to expand fully, which results in lower total lung capacity, vital capacity, and functional residual capacity. The restriction can occur due to intrinsic factors, such as interstitial lung diseases, or extrinsic factors, such as obesity or pleural abnormalities.

When less air is inhaled, the forced vital capacity and residual volume decline, meaning the lungs cannot hold as much air as they normally would. This diminished lung capacity affects the overall efficiency of gas exchange, leading to symptoms such as dyspnea (shortness of breath) during exertion.

In contrast to restrictive lung disease, obstructive lung diseases primarily relate to obstructed airways and often present with an increase in residual volume due to air trapping, which is not the primary issue in restrictive conditions. Understanding the specific mechanical changes in lung function aids in effective management and treatment strategies for conditions associated with restrictive lung disease.