Impact of the use of anti-diabetic drugs on survival of diabetic dialysis patients: a 5-year retrospective cohort study in Taiwan

Background: Type 2 diabetes mellitus (DM) and associated complications are common in patients with chronic kidney disease (CKD) and can increase morbidity and mortality. A longitudinal 5-year observational study was conducted to investigate whether the use of anti-diabetic medications or not affected survival rates of diabetic dialysis patients. Methods: Using a data sample of a million patients from Taiwan’s National Health Insurance Database, a retrospective cohort study surveyed patients with type 2 DM who began dialysis between 2002 and 2007. The study population was classified into groups using or not using anti-diabetic drugs. The group using anti-diabetic drugs was then categorized into 3 subgroups, including use of only oral hypoglycemic agents (OHAs), only insulin, and OHAs-combined insulin groups. Subjects of these four groups were followed 5 years or to date of death. Three major areas were analyzed: (1) demographic data and medical history; (2) survival prognosis and causes of death; and (3) effects on survival prognosis of different classes of OHAs. Results: A total of 912 patients fitting inclusion criteria were enrolled and followed-up for 5 years or to date of death. A total 465 patients died, and those not using anti-diabetic drugs (67.34 %) had a higher mortality rate than those using anti-diabetic drugs (46.42 %). After the multivariate analysis, group of OHAs-combined insulin had the lowest risk of death (HR 0.36, 95 % CI 0.27–0.47), followed by OHAs alone (HR 0.49, 95 % CI 0.38–0.63) and then insulin alone (HR 0.67, 95 % CI 0.51–0.88). To clarify four classes of OHAs (sulfonylurea, α-glucosidase inhibitors, meglitinide, and thiazolidinedione) are used in Taiwan for uremia patient with type 2 DM, and in our study, there were no significant differences in survival prognosis for the four drugs. Finally, the most common cause of death was infectious disease and there were no significant differences among the four groups. Conclusion: This 5-year observational study results suggested that diabetic dialysis patients with anti-diabetic drugs had a lower risk of death compared with those without anti-diabetic drugs. Despite insulin therapy, appropriate OHAs should play an important role in treating these patients.