Impact of Diabetes on Kidney Function Decline: Results from A 26-year Follow up of Community-based Cohort

4 Jul, 18

Background

Trajectories, particularly those related to estimated glomerular filtration rate (eGFR) among diabetes patients have an important role in adjudicating the possibility for early intervention and the prevention of chronic kidney disease (CKD) development. Nevertheless, long-term kidney disease trajectories are largely uncharacterized in people with and without diabetes in a general population.

Aim

To characterize patterns of eGFR decline associated with diabetes
To identify demographic, genetic, and modifiable risk factors associated with steeper eGFR decline in diabetes

Patient Profile

Participants from the community-based Atherosclerosis Risk in Communities (ARIC) study (n=15,517)
Patients were characterized based on their diabetes status:
- No diabetes (n=13698)
- Undiagnosed diabetes (fasting glucose ≥126 mg/dL or nonfasting glucose ≥200 mg/dL without medication or physician diagnosis; n=634)
- Diagnosed diabetes (a self-report of physician diagnosis or use of glucose lowering medication; n=1,185)

Exclusion Criteria

Individuals with eGFR ≤15 mL/min/1.73 m² or those having end-stage renal disease at baseline

Method

Study Design

Prospective community-based cohort study

Outcomes

Tracking the eGFR trajectories

Follow-up

26 years

Results

Overall, a linear association was observed between eGFR and age overtime irrespective of diabetes status
As per the adjusted linear mixed effect models, the decline in mean annual eGFR was slowest in people without diabetes. Those with undiagnosed diabetes had a steeper decline in mean annual eGFR as compared to people without diabetes.
The decline in eGFR was almost two times faster in diabetes patients vs. those without diabetes (difference vs. no diabetes for both, P < 0.001) (Table 1)

Table 1: Decline in mean annual eGFR in study groups

Diabetes status of study subjects	Annual decline in eGFR	95% confidence interval
Subjects without diabetes	-1.4 mL/min/1.73m²/year	-1.5 to -1.4
Patients with undiagnosed diabetes	-1.8 mL/min/1.73 m²/year	-2.0 to -1.7
Patients with diabetes	2.5 mL/min/1.73 m²/year	-2.6 to -2.4

African American race, systolic blood pressure (SBP) ≥140 mmHg, insulin use, and glycosylated hemoglobin (HbA1c) ≥9%, were associated with an increased risk of steeper annual decline in eGFR in patients with diabetes.

Conclusions

Diabetes is an important risk factor for kidney function decline.
Diabetes patients had a two-fold rapid decline in annual eGFR as compared to individuals without diabetes.
Individuals with undiagnosed diabetes also had steeper decline in eGFR vs. individuals without diabetes.
Glycemic control and hypertension are the key modifiable risk factors that can be targeted to prevent kidney disease in diabetes patients

Diabetes Care. Jun 1, 2018 (Published Ahead of print); doi: 10.2337/dc18-0277.