mg/dL. Thirteen million people in the United States were prescribed statins in 1997, and at least 15 million additional people were candidates for statin treatment.169 There is clear evidence that older patients show cardiovascular benefit from statin treatment.170 However, practitioners are not prescribing statins even when indicated. Large population surveys of statin use in high-risk patients show an inverse correlation with prescription of statins in older patients at high risk for vascular disease, with the lowest rate of statin treatment in the highest-risk patients.171 Biliary disease The prevalence of cholelithiasis increases with age. Bile seems to become increasingly lithogenic as a function of aging, with precipitation of supersaturated bile and concomitant crystallization of cholesterol or calcium bilirubinate. Much of the available human data has been obtained from subjects younger than 65 years; therefore, it is unclear whether gallbladder function is altered in extreme age. Some studies have shown impaired gallbladder function in older subjects. Fasting and postprandial gallbladder volumes were increased in subjects older than 35 years, with less complete emptying following a meal observed in older individuals.172 Increased gallbladder volumes correlated with cholelithiasis; however, no difference in fat-induced gallbladder emptying was observed in either male or female subjects older than 50 years compared with younger individuals.173 As in younger age groups, aged women may be more susceptible to impaired gallbladder contractility, with decreased contractile response to acetylcholine in postmenopausal women compared with aged men. Animal studies in aged guinea pigs suggest that deceased density of receptors for hormones such as cholecystokinin (CCK) and galanin may underlie the decreased gallbladder contractility and increased gallstone formation in this model.174 Impairment in intracellular calcium mobilization and decreased muscle compliance correlated with decreased CCK responsiveness. The functional significance of these animal studies to humans is unclear, because decreased CCK responsiveness in older human subjects was apparently compensated for by increased CCK release, with no net change in gallbladder kinetics in aging.175 Older patients tend to have more severe presentation of cholecystitis and complications of cholelithiasis, such as cholangitis. This may be related to the decrease in autonomic and sensory neuronal function with aging or due to delay in diagnosis for other reasons such as concerns about frailty. This increases the likelihood of conversion of laparoscopic to open procedures, with attendant increased risk of iatrogenic bile duct injury. Despite this, survival is equivalent to that in younger patients. A retrospective review of surgical biliary tract repair in a small cohort of 20 patients indicated that successful repair is possible in 85% of patients, which is comparable to that of younger populations.176 Effect of Aging on Pancreatic Structure and Function The exocrine pancreas possesses adequate reserve to maintain normal digestive capacity with aging. While there are some contradictory reports, there is little evidence for clinically significant decreases in pancreatic exocrine function in the elderly human.177 Age-related changes in pancreatic anatomy and histology include decreased pancreatic weight after the seventh decade in humans, with ductal epithelial hyperplasia, interlobular fibrosis, and