It’s believed that chronic pancreatitis (CP) is caused mainly due to excessive drinking, but a new study has found that the inflammation of the pancreas is not always alcohol-induced.

The rate of alcohol-related CP is lower when compared to other causes, according to the study published in Clinical Gastroenterology and Hepatology, the official journal of the American Gastroenterological Association.

Researchers who carried out the study said patients with no identifiable cause for their disease as well as those with non-alcohol-related causes represent an unexpectedly large subgroup, particularly among women.

“One of the more remarkable observations is that in more than 50 per cent of patients, alcohol was not considered as the causative factor of chronic pancreatitis,” said Gregory Cote, of Indiana University School of Medicine, who led the study.

“Future analyses will likely identify previously unrecognised genetic factors and/or interaction between genes and environmental factors as potential explanations of disease development.

“In the meantime, the era of dismissing all cases of chronic pancreatitis as alcohol-induced has undoubtedly come to a close.”

CP is an inflammation of the pancreas — the organ that produces insulin and glucagon and enzymes needed to digest food — that does not heal or improve, gets worse over time, and leads to permanent damage.

When inflammation occurs, the organ fails to produce right amount of these enzymes and hormones, making the body unable to digest food. Damage to the portions of the pancreas that make insulin may lead to diabetes.

For their study, the researchers analysed data of patients with CP and compared them to that of a control group enrolled in the North American Pancreatitis Study.

The study was designed to further the understanding of the role of gene-environment interactions in patients with recurrent acute pancreatitis and CP.

Among the groups, 44.5 per cent of patients had CP due to alcohol consumption, 26.9 per cent had non-alcohol related CP, and 28.6 per cent had CP of unknown cause.

Doctors observed that the current etiologic profile of CP patients evaluated at US referral centres is quite different from historical data.

Although alcohol remains the most common cause, a larger fraction of patients was considered to have non-alcoholic aetiologies, and in more than a quarter of patients, no identifiable cause of disease (idiopathic CP) was found.

Among the risk factors assessed, smoking was independently associated with idiopathic CP.

Pancreatitis usually begins as a sudden attack. When the pancreas becomes inflamed, its digestive enzymes attack the tissue that produces them. One of these enzymes, called trypsin, can cause tissue damage and bleeding, which may cause the pancreas tissue cells and blood vessels to swell.

In some cases, the attacks may recur frequently over time, which is known as CP. The onset of CP remains hard to define. This condition can be caused by alcohol, smoking and a multitude of other factors.