Abstract: SA-PO159
Both High Levels of Hb1Ac and HbA1c Variability Are Associated with Increased Risk of All-Cause Mortality in Patients with Diabetes and Maintenance Dialysis
Session Information
- Diabetic Kidney Disease: Clinical - II
October 27, 2018 | Location: Exhibit Hall, San Diego Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Diabetic Kidney Disease
- 602 Diabetic Kidney Disease: Clinical
Authors
- Afghahi, Hanri, Skaraborgs hospital, Skövde, Sweden, Sweden
- Nasic, Salmir, Skaraborg hospital, Skövde, Sweden
- Rydell, Helena, Karolinska University Hospital, Stockholm, Sweden
- Matei, Bogdan Sorin, Skaraborgs Hospital, Skövde, Sweden
- Svensson, Johan, Skaraborg Central Hospital, Skövde, Sweden
Background
Little is known of the association between variability of glycemic control and the risk of all-cause mortality in patients with diabetes and maintenance dialysis.
Aim: We assessed the relationship between long-term glycemic control, as estimated using mean values and variability of blood HbA1c, and the risk of all-cause mortality in diabetic patients on chronic dialysis.
Methods
We included 3930 patients (age 65±14 years, 63% men) with diabetes (type 1 or 2) and regular dialysis treatment [hemodialysis (HD), n = 2487 (63%); peritoneal dialysis (PD), n = 796 (20%); and both HD and PD, n = 647 (17%)]. Data were available from the Swedish Renal Register (SNR); the follow-up period was 2008 - 2017 (mean follow-up: 2.3± 2.2 years). HbA1c was defined as the mean of the reported values. HbA1c variability was determined by the coefficient of variation (CV), calculated as the ratio between the standard deviation (SD) and the mean HbA1c, HbA1c(SD)/HbA1c(mean). Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using time-dependent Cox models, which included adjustments for demographics, laboratory findings and comorbidity.
Results
During follow-up, 2027 (52%) deaths occurred. We used HbA1c 31-42 mmol/mol (5- 6%) as reference group. The multivariate Cox analyses showed increased mortality risk for HbA1c 62-72 mmol/mol (7.8-8.7%; HR 1.40, 95% CI 1.17 - 1.65) and HbA1c 73-82 mmol/mol (8.8-9.7%; HR 1.70, 95% CI 1.34 - 2.13) (both P<0.001).
In a subanalysis of 2061 patients, we estimated the association between HbA1c variability and the risk of death. HbA1c CV< 0.5 was used as reference group. In the multivariate Cox analyses, HbA1c CVs of 2.84-4.60 and > 4.6 were associated with increased risk of mortality (HR 1.98, 95% CI 1.54- 2.47 and HR 1.99, 95% CI 1.54- 2.57, respectively) (both P<0.001).
Conclusion
We did not find a J-shaped relation between HbA1c level and risk of mortality in dialysis patients with diabetes. Instead, low mean HbA1c was associated with improved survival, and HbA1c variability was strongly associated with increased risk of all-cause mortality. These findings suggest that glycemic control as well as the stability of glycaemia level are important in patients with diabetes and maintenance dialysis treatment.