Table 1.

Physiologic changes with aging.

Organ system	Changes	Effect on chemotherapy
Renal	Decreased glomerular filtration	Decline in renal drug clearance that increases risk of drug toxicity
	Impaired water and electrolyte handling	Increased risk of dehydration
Gastrointestinal	Decreased gastric blood flow and delayed gastric emptying	Variable drug absorption
	Decreased absorptive capacity	Decreased absorption of oral drugs
	Decreased mucosal repair	Vulnerability to mucositis
Hepatobiliary	Decreased liver mass and blood flow	Reduced hepatic metabolism
	Reduction in cytochrome P450 activity	Greater vulnerability to P450 associated with drug interactions
Body composition	Increased fat and decreased water	Changes drug volume of distribution
Hematologic	Decreased marrow cellularity, proliferation, and mobilization	Impaired response to cytopenias, delayed blood count recovery, and higher risk of infection