Gallstone recurrence after medical dissolution. An overestimated threat?

We assessed gallstone recurrence rate in 42 patients diagnosed as having complete gallstone dissolution on bile acid therapy. By contrast with most previous studies, this diagnosis was based on ultrasound as well as on radiology, and only patients having their first gallstone recurrence were included in the study. Patients were followed for periods varying from 6 months to 7 years (median 30 months). Eleven patients had recurrences, giving an overall recurrence rate of 26%. A life analysis table was constructed by an actuarial method to compensate for the different lengths of follow-up in individual patients. Corrected recurrence rates by life table analysis were 15%, 21%, 25%, 36%, 45%, 45% and 45% at 1, 2, 3, 4, 5, 6 and 7 years respectively; for the same time intervals, cumulative recurrence rate overestimated the risk of gallstone recurrence (14%, 22%, 31%, 50%, 61%, 79% and 92%). We conclude that previous figures for recurrence rate have been an overestimate; but recurrence rate remains substantial over the first 5 years, and then levels off.