BMI Linked To Gallstones
July 12, 2013

Link Between BMI And Increased Risk Of Gallstones Discovered

redOrbit Staff & Wire Reports - Your Universe Online

Individuals with elevated body mass index (BMI) levels appear to be at greater risk of developing gallstones, according to new research appearing in a recent edition of Hepatology, a journal of the American Association for the Study of Liver Diseases.

Women are at greater risk of developing the pebble-like materials, which can result from the presence of excess cholesterol, bile salts, or bilirubin in bile stored in the gallbladder, the researchers report. Previous research had shown a link between higher BMI and an increased risk of gallstone disease, but until now it was unclear whether or not the association between the two conditions was a causal one.

Dr. Anne Tybjaerg-Hansen of Rigshospitalet, Copenhagen University Hospital in Denmark and colleagues studied nearly 78,000 individuals selected using what is known as the Mendelian randomization approach. This method uses genetic variation to study the impact of modifiable risk factors as the cause of the disease, the study authors explained.

A total of 4,106 participants developed symptomatic gallstone disease during a follow-up period of 34 years, they said. Those individuals who contracted the condition were more likely to be older, female and less physically active. Furthermore, the researchers found people with gallstones tended to use hormone replacement therapy and drink less alcohol than those without the disease.

The results of the study also revealed increased BMI was associated with gallstone disease risk with an overall hazard ratio (HR) of 2.84. Amongst men the HR was 1.51, while amongst women it was 3.36, Dr. Tybjaerg-Hansen and her colleagues reported. Their findings indicate there was a 7 percent increase of developing gallstone disease for every 1 kg/M2 increase in a person's BMI score.

"Obesity is a known risk factor for gallstone disease and our study suggests that elevated BMI likely contributes to the development of this disease," Dr. Tybjaerg-Hansen explained in a statement. "These data confirm that obesity adversely affects health, and lifestyle interventions that promote weight loss in overweight and obese individuals are warranted."

According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), gallstones are most common in women - especially those who are pregnant, use hormone replacement therapy, or take birth control pills; anyone over the age of 60; American Indians and Mexican Americans; overweight or obese men and women; those who lose weight quickly or fast; those with diabetes or a family history of gallstones; and anyone taking cholesterol-lowering drugs.