Cholecystectomies in Korea more than tripled in fifteen years. The national study points at CT scanners

A gallstone that has never caused pain is not a disease so much as a finding. Whether it becomes a diagnosis depends on whether anybody looks. Over fifteen years, South Korea looked a great deal more often, and the number of gallbladders removed each year followed.

What the national data show#

A study of the National Health Insurance Service database covering the entire Korean population between 2003 and 2017, published in Annals of Surgical Treatment and Research, tracked the age-standardised rate of cholecystectomy against a 2010 population standard. Standardising in this way strips out the effect of an ageing population, so the increase it records is not simply a country growing older.

The rate rose with age, was consistently higher in women than in men, and shifted toward specialised centres. Length of stay fell by more than a third, which is what the spread of laparoscopic practice looks like in claims data.

Why the authors point at imaging#

The explanation the authors offer is not a change in disease. It is a change in detection: increasing use of computed tomography, they write, could be a primary cause of the trend. A scan ordered for something else finds a stone that would otherwise have gone unrecorded, and a finding that has been recorded is difficult to leave alone.

This is a familiar shape. Incidental detection has driven measured incidence in thyroid cancer, in renal masses, and in pulmonary nodules, in each case producing more treatment without a matching change in what was making people ill.

The counterweight in the evidence#

What happens to a gallstone left alone was quantified this March. A systematic review and meta-analysis published in PLOS ONE pooled eight cohort studies covering 25,924 people with gallstones that had never caused symptoms.

• 10 percent had developed symptoms at five years.
• 19 percent had developed symptoms at ten years.
• 26 percent had developed symptoms at fifteen years.

The pooled incidence rate was roughly two people per hundred per year. The review's authors recommend conservative management for most patients with asymptomatic gallstones, with attention to the minority at higher risk of developing symptoms.

What the trend data cannot settle#

It would be convenient to read these two findings together as evidence that Korea is operating too often. The claims data does not support that conclusion, and it is worth being precise about why.

1. Insurance claims do not record whether a patient was symptomatic, so the study cannot say how many of the additional operations were performed on incidental findings.
2. Rising detection and rising genuine disease are not mutually exclusive; gallstone prevalence has been increasing internationally.
3. The meta-analysis describes what happens to stones left alone, not what would have happened to the particular stones Korean surgeons removed.