Which factor tends to increase baseline natriuretic peptide levels with aging?

• A. Aging
• B. Acute infection
• C. Dehydration
• D. Exercise

Answer: (A)

Natriuretic peptides track how much the heart’s ventricles are stretched or stressed. As people age, the heart undergoes subtle structural changes: the left ventricle becomes stiffer (diastolic function declines), filling pressures can drift upward, and vascular stiffness increases afterload. All of this tends to raise the baseline level of natriuretic peptides even when there are no obvious heart problems. In addition, aging can slow clearance of these peptides by the kidneys, contributing further to higher baseline levels. While factors like infection or recent exercise can transiently raise natriuretic peptides, the typical age-related pattern is a gradual, baseline increase due to these chronic, non-acute changes.