A 75-year-old patient with decreased lung compliance demonstrates reduced forced expiratory volume (FEV1). Which mechanism explains this decline in pulmonary function, given age-related tissue changes?

💡 Explanation

Reduced lung compliance in aging patients results from decreased elastin fiber recoil, because elastin provides the lungs with their elasticity, facilitating efficient exhalation. Therefore, loss of elasticity reduces FEV1, rather than increased collagen cross-linking, reduced surfactant, or elevated surface tension being the primary drivers.

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