Table 4 Cox regression models showing hazard ratios (HRs) regarding severe diabetic retinopathy for low and moderate versus high total LTPA, intensity, frequency and duration

Model 1: low, moderate, high

1.31 (0.91–1.89) 1.10 (0.78–1.55) 1.00, N = 1612

0.92 (0.64–1.33) 0.92 (0.69–1.23) 1.00, N = 1576

1.40 (1.03–1.89) 1.24 (0.93–1.66) 1.00, N = 1595

0.94 (0.62–1.43) 0.92 (0.70–1.21) 1.00, N = 1498

Model 2: Model 1 + gender, duration of diabetes, age at onset of diabetes, kidney function

1.32 (0.91–1.90) 1.12 (0.80–1.59) 1.00, N = 1609

1.01 (0.69–1.47) 1.02 (0.75–1.38) 1.00, N = 1573

1.41 (1.04–1.92) 1.21 (0.90–1.62) 1.00, N = 1592

0.97 (0.64–1.48) 0.98 (0.74–1.30) 1.00, N = 1495

Model 3: Model 2 +SBP, TG, BMI, HbA_1c

1.27 (0.88–1.85) 1.34 (0.94–1.91) 1.00, N = 1565

0.93 (0.63–1.38) 1.03 (0.76–1.41) 1.00, N = 1529

1.25 (0.91–1.71) 1.21 (0.90–1.63) 1.00, N = 1548

1.00 (0.65–1.54) 1.12 (0.83–1.47) 1.00, N = 1452

Model 4: Model 3 + history of smoking

1.22 (0.83–1.77) 1.32 (0.92–1.88) 1.00, N = 1518

0.82 (0.56–1.23) 0.98 (0.72–1.34) 1.00, N = 1482

1.18 (0.85–1.62) 1.21 (0.90–1.63) 1.00, N = 1502

0.96 (0.62–1.48) 1.08 (0.81–1.44) 1.00, N = 1408