Gallstone disease in an elderly population: the Silea study

BACKGROUND: Little is known on gallbladder emptying and gallstone composition in the elderly. AIMS AND SUBJECTS: Cross-sectional survey on the prevalence of gallstone disease and associated factors, gallstone characteristics and gallbladder emptying in a population aged > or = 60 years. METHODS: Gallstone number and size as well as gallbladder motor function were assessed by ultrasound. Gallstone composition and pattern were evaluated by conventional radiology and computed tomography (CT) based on Hounsfield units (HU). RESULTS: Gallstones were found in 148/1,065 subjects (13.9%), while 136 subjects (12.8%) were cholecystectomized with an overall prevalence of gallstone disease of 26.7% (sex ratio: F > M). Multiple gallstones (62.7%) and small gallstones (52%, diameter < or = 15 mm) were seen; silent gallstones accounted for 93.9% of the total. Only diabetes mellitus in women was significantly associated with cholelithiasis. Gallbladder fasting volumes were larger in gallstone carriers than in controls (P < 0.01); residual and ejection volumes were also significantly greater in gallstone carriers, whereas ejection fractions were similar in the two groups (50.3% +/- 2.4 versus 54.9% +/- 3.0; not significant). Gallstone calcifications were detected in 29/91 gallstone carriers by X-ray and in another 20 by CT (HU > 90). Moreover, 35 gallstone carriers had a score < or = 50 HU and six had attenuation values between 50 and 90 HU. Six gallstone patterns were identified: hypo-isodense, homogeneously dense, rimmed, laminated, core-hyperdense, gas-containing. CONCLUSIONS: In the elderly, the prevalence of gallstone disease is very high, especially in women, but gallstone size, number and pattern and gallbladder emptying do not differ from those reported in the middle-aged gallstone population. Advanced age is associated with a high rate of calcified, probably pigment stones.