Obesity with abundant subcutaneous adipose tissue increases the risk of post-ERCP pancreatitis

The risk factors for post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) have been widely investigated. However, studies focusing on the body mass index (BMI) and distribution of adipose tissue have not been reported. Therefore, we examined the correlation between PEP and these factors. A total of 583 consecutive endoscopic retrograde cholangiopancreatography (ERCP)-na < ve patients undergoing therapeutic ERCP were retrospectively analyzed. Subjects were categorized into four groups by BMI: underweight, normal, overweight, and obesity; the PEP rates were compared. In addition, the relationship between PEP and parameters of obesity, visceral and subcutaneous adipose tissue as well as abdominal circumference was investigated. PEP rate was significantly higher in obesity (30 %) and lower in normal (3 %, P < 0.001). The PEP rate in underweight (7.3 %) was conversely higher than in normal. As for parameters of obesity, only subcutaneous adipose tissue was correlated with PEP incidence (P = 0.009). The correlation of PEP incidence with BMI and subcutaneous adipose tissue was separately reconfirmed by multivariate analysis including female gender and guidewire placement; these factors showed a tendency toward differences in univariate analysis. Obesity could be a risk factor for PEP. In the obesity group, an excess of subcutaneous adipose tissue might be an especially important factor related to PEP incidence.