Ten-year incidence and natural history of gallstone disease in a rural population of women in central Italy. The Rome Group for the Epidemiology and Prevention of Cholelithiasis (GREPCO).

AIMS: To investigate the incidence, risk factors and natural history of gallstone disease, a random sample of females belonging to a rural population was enrolled in a ten-year longitudinal study.

METHODS: The study has been performed in a small town on the hills south of Rome. In 1985, a random sample of 426 females, aged 20-69 years, was screened by real-time ultrasonography for gallstones and previous cholecystectomy. Screening methods included anthropometry, collection of a blood sample and a questionnaire on the occurrence of abdominal symptoms. During 1995, all these subjects were invited for a 10-year follow-up examination.

RESULTS: The overall 10-year incidence of gallstone disease was 6.3% (5.5% of new gallstones and 0.8% of cholecystectomies). Only 23.1% of the women with gallstones were aware of their condition. More than three quarters (76.9%) had not suffered biliary pain. Univariate and multivariate analyses demonstrated a positive independent association of new gallstone disease with body mass index and parity. Out of the initially asymptomatic gallstone women, 15.4% experienced at least one episode of biliary pain, 23.1% were submitted to elective cholecystectomy and 61.5% remained asymptomatic.

CONCLUSIONS: The study demonstrates a high incidence of gallstone disease in women belonging to a rural free-living population in Italy and suggests body mass index and parity as possible true risk factors. Moreover, it confirms that a remarkable proportion of asymptomatic patients become symptomatic and eventually undergo cholecystectomy.