Tobacco use, obesity, and heavy use of alcohol are the factors most likely to increase risk for pancreatic diseases, researchers report in the October issue of Clinical Gastroenterology and Hepatology. Vegetables and fruit, on the other hand, appear to reduce risk. Strategies to prevent acute pancreatitis, chronic pancreatitis, and pancreatic cancer should consider these factors.
Diseases of the pancreas, the most common of which are acute pancreatitis, chronic pancreatitis, and pancreatic cancer, affect more than 330,000 people in the United States each year.
A number of risk factors have been reported for these disorders, but studies have been limited in that they were not conducted on a general population, introduced selection bias, or focused on only 1 factor at a time.
Ammar Alsamarrai et al performed a systematic review and meta-analysis of high-quality population-based studies to better understand, quantify, and compare modifiable risk and protective factors for the 3 most common pancreatic diseases.
They collected data from 51 population-based studies of more than 3 million individuals and nearly 11,000 patients with pancreatic diseases, investigating the effects of 31 different factors. Alsamarrai et al used data from only cohort studies, in which information about exposure to putative risk factors was collected when subjects were disease free, to avoid recall bias.
Current tobacco use was the single most important risk factor for pancreatic diseases, with a relative risk of 1.87, followed by obesity (relative risk of 1.48) and heavy use of alcohol (>20 drinks per week, relative risk of 1.37).
Tobacco and heavy use of alcohol had bigger effects on risk of acute pancreatitis and chronic pancreatitis than on pancreatic cancer.
Although smoking has been shown to be a risk factor for pancreatic cancer, Alsamarrai et al also associated pancreatic cancer with heavy alcohol consumption.
Compared with individuals with a normal body mass index (BMI, 18.5 to 25 kg/m2), the risk of developing a pancreatic disease in overweight and obese individuals increased significantly, by 29% and 50%, respectively.
Alsamarrai et al state however that there is no consensus on whether high BMI is associated with risk of pancreatic cancer—different studies have shown different results. The association may be non-linear or apply to only certain subgroups of patients.
Vegetable and fruit consumption reduced the overall risk of pancreatic disorders by about 30%. Vegetable consumption had stronger association with protection against acute pancreatitis and fruit consumption with protection against pancreatic cancer.
Intake of added sugar, juice, cholesterol-lowering drugs, carbohydrates, fish, polyunsaturated fatty acid, aspirin, or vitamin B6 had no significant association with pancreatic cancer; nor did glycemic load, glycemic index, or hypertension.
In an editorial that accompanies the article, Albert B. Lowenfels and Patrick Maisonneuve explain that acute pancreatitis is frequently caused by alcohol or by gallstones. In most countries, alcohol consumption has remained constant or decreased, so the increasing prevalence of acute pancreatitis most likely is related to increasing cases of gallstones, associated with obesity. The editorialists therefore propose that controlling obesity should reduce the frequency of acute pancreatitis.
Lowenfels and Maisonneuve add that other reports have suggested that a combination of healthy lifestyle measures (nonsmoking, limited alcohol use, a Mediterranean diet, body weight control, and regular physical activity) might prevent a substantial fraction of all pancreatic cancers and perhaps a similar proportion of benign pancreatic disease.
The editorialists conclude that this study should remind us of the importance of avoiding known risk factors for pancreatic diseases, and the potential benefit of increasing our intake of preventive substances such as fruits and vegetables. They hope that we will be able to add pancreatic diseases to such illnesses as stroke and heart disease, for which preventive efforts are likely to be effective.