Long-term survival, risk factors and causes of mortality in surgically treated chronic pancreatitis

Chronic pancreatitis (CP) is a complex disease with a high complications rate, poor quality of life and considerable mortality. Prospective investigations on long-term outcomes in chronic pancreatitis are scarce. Thus, we aimed to assess long-term survival, causes of death and impact of risk factors on survival in a cohort of surgically managed patients with chronic pancreatitis.

After IRB approval, a prospective longitudinal cohort study with long-term follow-up (up to 19.6 years) was conducted. All consecutive single center patients operated between 1997 and 2019 were included. Data on health and social status, risk behavior, history of CP, indications for surgery, comorbidities and causes of death were collected. Survival analysis was performed using Kaplan-Meier analysis. Cox proportional multivariate hazard regression was used to assess the impact of risk factors on mortality. The results are reported as the hazard ratio (HR) with the 95% confidence interval (CI). The log-rank test was used to test for differences in survival between groups.

A total of 161 patients with CP were subjected to operative management due to chronic pain or local complications of CP. Forty-eight patients (29.8%) died during the follow-up period. Mortality rate was 32.8 per 1000 patient-years (PY) since the diagnosis of CP. Standardized mortality ratio (SMR) was 1.8 (2.7 for the subgroup of continuous alcohol users). Median survival after surgical treatment was 13.3 years. Univariate analysis revealed the following risk factors on survival: preoperative and postoperative continuous moderate or heavy alcohol consumption, heavy smoking, age ≥50 years, Charlson's comorbidity index (CCI) ≥4 and 2-3, unemployment, disability, insulin-dependent diabetes, pancreatic exocrine insufficiency (PEI), and low body mass index (BMI). In multivariate regression analysis lower survival was associated with continuous moderate/heavy alcohol consumption (hazard ratio (HR) 2.27), history of heavy smoking (HR 4.40), unemployment (HR 2.49), CCI 2-3 and ≥4 (HR 2.53 and HR 3.16, respectively), and BMI <18.5 (HR 4.01). Behavioral risk factors accounted for the vast majority of deaths due to chronic alcoholic liver disease (21 cases, 43.7%), smoking-related diseases (15 cases, 31.3%). CP-related mortality was 4.2%.

Long-term outcomes of surgically treated chronic pancreatitis was associated with low CP-related mortality. Alcohol-related and smoking-related diseases caused the vast majority of deaths. Thus, surgery provides the best results in patients, preventing postsurgical relapse of original behavioral risks. For achieving this, ongoing postoperative support would be highly beneficial.