MRI measurements of pancreatic fat content in the general population and their relationship with age, gender, and body mass index

Increased fat deposition in the pancreas is known to be associated with an increased risk of type 2 diabetes mellitus and metabolic syndrome. However, few studies have measured the pancreatic fat content in a normal population or tried to set a threshold for defining nonalcoholic fatty pancreatic disease. Two hundred thirty-seven healthy subjects (107 males and 130 females; age range of 21-79 years; mean age of 50 ± 15 years) underwent 3-point Dixon magnetic resonance imaging to measure the proton density fat fraction (PDFF) in the head, body, and tail of the pancreas. Subjects were divided into 5 age ranges (21-30, 31-40, 41-50, 51-60, and > 60 years old). After testing data for normality, parametric and nonparametric statistical tests were used to study how pancreatic fat content varied with gender, age, and body mass index. Median pancreatic fat content was 3.33% (inter quartile range 1.82-6.16%) and did not vary significantly between the head, body, and tail. Over all ages, men had higher pancreatic PDFF than women (P = .010) as well as in each of the 5 age ranges. The trend for pancreatic fat content to increase with age was highly statistically significant (P < .001). In men, median PDFF increased from 3.22% in the 21 to 30-year-old group to 6.26% in the > 60 group. In women, the same figures were 1.44% and 4.41%. There was also a statistically significant increase in pancreatic PDFF with body mass index. Pancreatic fat was homogeneous and evenly distributed in the head, body, and tail of the pancreas. Pancreatic PDFF was higher in men, elderly people, and in obesity.