Metformin Treatment Is Associated with a Decreased Risk of Nonproliferative Diabetic Retinopathy in Patients with Type 2 Diabetes Mellitus: A Population-Based Cohort Study
Table 5
Risk of NPDR in different metformin dose and aDCSI score groups (metformin+DPP4i vs. metformin alone).
Total
<3 months
3 months to 1.5 years
>1.5 years
HR (95% CI)
Adjusted HR (95% CI)
HR (95% CI)
Adjusted HR (95% CI)
HR (95% CI)
Adjusted HR (95% CI)
HR (95% CI)
Adjusted HR (95% CI)
Metformin dose
≤360 DDDs
0.50 (0.33–0.76)
0.49 (0.32–0.75)
0.37 (0.21–0.67)
0.38 (0.21–0.68)
0.48 (0.19–1.23)
0.46 (0.17–1.19)
1.37 (0.59–3.17)
1.34 (0.57–3.15)
361–720 DDDs
0.40 (0.25–0.64)
0.36 (0.22–0.59)
0.38 (0.20–0.74)
0.36 (0.19–0.69)
0.28 (0.09–0.94)
0.28 (0.08–0.96)
0.58 (0.24–1.42)
0.45 (0.18–1.15)
>720 DDDs
0.61 (0.41–0.9)
0.59 (0.39–0.88)
0.51 (0.31–0.85)
0.50 (0.3–0.83)
0.65 (0.28–1.49)
0.62 (0.26–1.44)
1.19 (0.39–3.65)
1.36 (0.41–4.49)
aDCSI score
0
0.46 (0.34–0.62)
0.45 (0.33–0.61)
0.36 (0.24–0.54)
0.36 (0.24–0.55)
0.50 (0.25–0.97)
0.49 (0.24–0.97)
1.05 (0.51–2.17)
0.96 (0.46–2.02)
1
0.31 (0.16–0.58)
0.32 (0.17–0.60)
0.23 (0.09–0.58)
0.23 (0.09–0.58)
0.15 (0.02–1.09)
0.16 (0.02–1.18)
0.71 (0.26–1.96)
0.53 (0.18–1.58)
≥2
0.47 (0.24–0.91)
0.45 (0.23–0.89)
0.41 (0.18–0.95)
0.38 (0.16–0.89)
0.88 (0.18–4.36)
0.96 (0.17–5.35)
0.56 (0.12–2.54)
0.44 (0.09–2.13)
Adjusted for gender, age, comorbidities, medications, aDCSI scores, and other antidiabetic drugs use. NPDR: nonproliferative diabetic retinopathy; DDD: defined daily dose; aDCSI scores: adapted Diabetes Complications Severity Index scores; HR: hazard ratio.
