Preoperative diabetes complicates postsurgical recovery but does not amplify readmission risk following pancreatic surgery

Abstract

Background: Diabetes is a significant and prevalent medical condition associated with increased comorbidities, longer hospital length of stay, and higher healthcare costs. We aimed to assess the association between diabetes mellitus and postoperative outcomes following pancreatic surgeries.

Methods: Records for patients with major elective pancreatic surgeries were retrieved retrospectively from the Nationwide Readmission Database (2010-2014). Association of diabetic status with postoperative complications, in-hospital mortality, length of stay (LOS), readmission rate, and hospital costs were investigated. Logistic regression and decision tree analyses were employed to predict adverse outcomes.

Results: A total of 8,401 patients who had pancreatic surgery were included. They were categorized according to their diabetic diagnosis. Results showed that diabetic patients had a higher risk of postoperative complications compared to non-diabetics (OR: 1.27, 95% CI: 1.08-1.49, P=0.003). Bleeding and renal complications were the most significant. Uncontrolled diabetes significantly required a longer hospital stay (9.17±4.28 vs. 8.03±4.96 days, P=0.001), and incurred higher hospital costs ($34,171.04±$20,846.61 vs. $28,182.21±$24,070.27, P=0.001). After multivariate regression, no association was found with in-hospital mortality or readmission rates; however, diabetic patients' length of stay during readmission was increased at 30- and 90-day readmissions (P=0.004 and 0.007, respectively).

Conclusions: Among patients who underwent pancreatic surgery, those with diabetes had a higher rate of postoperative complications compared to non-diabetics. Additionally, diabetic patients had higher hospital charges and costs during primary admission. Initial analysis of patients with diabetes showed they had higher rates of 30- and 90-day readmissions, though this did not maintain significance after regression analysis. Exploring the mechanisms underlying this finding would aid in preventing postoperative complications and reducing healthcare costs.

Keywords: Pancreatectomy; cost; mortality; national database; readmission.

Figure 1

Workflow for selection of the study population. Grey boxes indicate patients included in the study. Values in the workflow chart represent the actual frequencies without national estimation. NRD, National Readmission Database; LOS, length of stay.

Figure 2

Prevalence of pancreatic surgeries and clinical status of diabetic patients. (A) Prevalence of major elective pancreatic surgery. All values are presented as weighted national estimates. (B) Type of diabetes. (C) Control status of patients. (D) Presence of complications. (E) Types of complications. Data are presented as a percentage. Two-tailed Chi-square was performed between different years. Statistical significance was set at P<0.05. T1DM, type 1 diabetes mellitus; T2DM, type 2 diabetes mellitus.

Figure 3

Types of postoperative complications following pancreatic surgeries. (A) Frequency of complications in diabetic and non-diabetic groups. All numbers are presented as weighted national estimates. A two-sided Chi-square test was used. (B) Unadjusted odds and 95% confidence intervals of postoperative complications in diabetic patients are shown in the right panel. Significant values are represented by red and blue bars for increased and decreased odds, respectively. CVS, cardiovascular system; OR, odds ratio.

Figure 4

Postoperative morbidity and readmission rates in patients who underwent a pancreatic surgical procedure. (A) Frequency of mortality at index hospitalization and during readmission in diabetic and non-diabetic cohort. (B) Frequency of 30 days and 90 days readmission classified by diabetes status. A two-sided Chi-square test was used.

Figure 5

Causes of readmission in diabetic and non-diabetic cohorts.

Figure 6

Healthcare burden of diabetes following pancreatic surgery. (A) Length of hospital stay at primary admission and readmission following pancreatic surgery. (B) Hospital cost at primary admission and readmission following pancreatic surgery. Bars represent mean and 95% confidence intervals. Mann-Whitney U test was used.