research reveals a causal association between elevated body mass index (BMI)
and increased risk of gallstone disease. Results published in Hepatology, a
journal of the American Association for the Study of Liver Diseases, show women
are at greater risk of developing gallstones.
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
describe gallstones as a pebble-like material, which can develop when there is
excess cholesterol – accounting for 80% of all gallstones – bile salts or bilirubin
in bile stored in the gallbladder. Gallstone disease is one of the most common
and costly gastrointestinal diseases – accounting for $5.8 billion. Prior studies
have shown that greater BMI is associated with increased risk of gallstone
disease; however it is unclear if it is the cause of the disease.
understanding of the connection between BMI and gallstone risk, a team led by
Dr Anne Tybjærg-Hansen from Rigshospitalet, Copenhagen University Hospital in
Denmark studied 77 679 participants from the general population, employing a
Mendelian randomisation approach – a method using genetic variation to study the
impact of modifiable risk factors as the cause of a disease. There were 4 106
participants who developed symptomatic gallstone disease during the 34 years of
with gallstone disease were more likely to be older, female, and less
physically active. Researchers found that those with gallstones often used
hormone replacement therapy and drank less alcohol than those without the
disease. Analyses show that increased BMI was associated with gallstone disease
risk with an overall hazard ratio (HR) of 2.84. When looking at BMI and gender,
the team found that women had a higher risk of developing gallstone disease
than men (HR=3.36 and 1.51, respectively).
indicate that gallstone disease risk increased 7% for every 1 kg/M2 increase in
BMI. "Obesity is a known risk factor for gallstone disease and our study
suggests that elevated BMI likely contributes to the development of this
disease," concludes Dr. Tybjærg-Hansen. "These data confirm that
obesity adversely affects health, and lifestyle interventions that promote
weight loss in overweight and obese individuals are warranted."