Adverse Outcomes After Noncardiac Surgery in Patients With Diabetes: A nationwide population-based retrospective cohort study

OBJECTIVE

To investigate whether diabetes affects perioperative complications or mortality and to gauge its impact on medical expenditures for noncardiac surgeries.

RESEARCH DESIGN AND METHODS

With the use of reimbursement claims from the Taiwan National Health Insurance system, we performed a population-based cohort study of patients with and without diabetes undergoing noncardiac surgeries. Outcomes of postoperative complications, mortality, hospital stay, and medical expenditures were compared between patients with and without diabetes.

RESULTS

Diabetes increased 30-day postoperative mortality (odds ratio 1.84 [95% CI 1.46–2.32]), particularly among patients with type 1 diabetes or uncontrolled diabetes and patients with preoperative diabetes-related comorbidities, such as eye involvement, peripheral circulatory disorders, ketoacidosis, renal manifestations, and coma. Compared with nondiabetic control patients, coexisting medical conditions, such as renal dialysis (5.17 [3.68–7.28]), liver cirrhosis (3.59 [2.19–5.88]), stroke (2.87 [1.95–4.22]), mental disorders (2.35 [1.71–3.24]), ischemic heart disease (2.08 [1.45–2.99]), chronic obstructive pulmonary disease (1.96 [1.29–2.97]), and hyperlipidemia (1.94 [1.01–3.76]) were associated with mortality for patients with diabetes undergoing noncardiac surgery. Patients with diabetes faced a higher risk of postoperative acute renal failure (3.59 [2.88–4.48]) and acute myocardial infarction (3.65 [2.43–5.49]). Furthermore, diabetes was associated with prolonged hospital stay (2.30 [2.16–2.44]) and increased medical expenditures (1.32 [1.25–1.40]).

CONCLUSIONS

Diabetes increases postoperative 30-day mortality, complications, and medical expenditures in patients undergoing in-hospital noncardiac surgeries.Diabetes is a common chronic disease that causes widespread disability and death, with a global prevalence of 2.8% in 2000 and an estimated prevalence of 4.4% in 2030 (1). In the U.S., the national burden of diabetes was estimated to be $245 billion in 2012 (2). The epidemiology, pathogenesis, prevention, and treatment of diabetes have been well established over the past 2 centuries (3).Diabetes is an independent determinant of increased risk of perioperative complications and mortality in cardiovascular surgeries (4,5), yet how extensively diabetes affects postoperative mortality and complications in noncardiac surgeries has not been determined. Some studies indicated that survival outcomes and perioperative complications in noncardiac surgeries do not differ between patients with and without diabetes (6,7), whereas other research showed conflicting data about whether diabetes increased perioperative complications, mortality, hospital stay, and health care expenditures (8–16).Previous studies were limited by several factors, including a focus on a single type of noncardiac surgery (6,8,10,12,14), small sample size (6,7,9,13), inappropriate selection of nondiabetes control subjects (6–16), inadequate adjustment for potential confounders (7,9–12,15), and reporting of a single outcome after surgery (10,16). It remains unclear whether coexisting medical conditions, types of diabetes, glycemic control, and diabetes-related comorbidities affect postoperative outcomes in patients with diabetes.This study used Taiwan National Health Insurance Program reimbursement claims to investigate postoperative complications, 30-day mortality, length of hospital stay, and medical expenditures after adjustment by propensity score-matched pair method in patients with diabetes undergoing noncardiac surgeries. We also investigated the impact of coexisting medical conditions and diabetes-related comorbidities on postoperative 30-day mortality among patients with diabetes.