Table 3.
Hazard ratios for the incidence of diabetic retinopathy stratified by the mean glycated hemoglobin level and age at baseline
| Mean HbA1c <7.0% | Mean HbA1c ≥7.0% | Interaction P | Age at baseline <60 years | Age at baseline ≥60 years | Interaction P | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| HR (95% CI) | P‐value | HR (95% CI) | P‐value | HR (95% CI) | P‐value | HR (95% CI) | P‐value | |||
| Model 1 (events/patients) | 75/327 | 70/160 | 83/270 | 62/217 | ||||||
| Mean 1–2h‐PBLBG (1 mmol/L) | 1.12 (1.02–1.23) | 0.023 | 1.11 (0.99–1.24) | 0.066 | 0.56 | 1.12 (1.02–1.22) | 0.014 | 1.09 (0.94–1.27) | 0.27 | 0.74 |
| Mean HbA1c (%) | 3.46 (1.76–6.81) | 0.0003 | 1.99 (1.26–3.14) | 0.003 | 1.65 (1.14–2.39) | 0.009 | 2.31 (1.56–3.44) | <0.0001 | ||
| Model 4 (events/patients) | 47/220 | 45/103 | 55/185 | 37/138 | ||||||
| Mean 1–2h‐PBBG (1 mmol/L) | 1.12 (1.00–1.24) | 0.042 | 1.05 (0.94–1.18) | 0.39 | 0.73 | 1.12 (1.02–1.23) | 0.023 | 1.07 (0.93–1.22) | 0.35 | 0.92 |
| Mean HbA1c (%) | 3.12 (1.37–7.13) | 0.007 | 2.48 (1.27–4.84) | 0.008 | 1.66 (1.06–2.60) | 0.027 | 3.13 (1.73–5.68) | 0.0002 | ||
| Model 7 (events/patients) | 65/270 | 61/136 | 73/226 | 53/180 | ||||||
| Mean 1–2h‐PLBG (1 mmol/L) | 1.12 (1.03–1.21) | 0.011 | 1.07 (0.99–1.16) | 0.11 | 0.25 | 1.08 (1.01–1.15) | 0.023 | 1.12 (0.96–1.30) | 0.15 | 0.32 |
| Mean HbA1c (%) | 3.27 (1.60–6.68) | 0.001 | 2.24 (1.40–3.58) | 0.0008 | 1.69 (1.17–2.43) | 0.005 | 2.24 (1.48–3.39) | 0.0001 | ||
Intrapersonal mean values during the 2‐year period from the first visit were used as baseline data. Model 1 included the number of 1–2 h post‐breakfast and post‐lunch blood glucose (1–2h‐PBLBG) measurements (ln‐transformed), age, sex, duration of diabetes, mean systolic blood pressure and hypoglycemia as covariates. Model 4 included the number of 1–2 h post‐breakfast blood glucose (1–2h‐PBBG) measurements (ln‐transformed), age, sex, duration of diabetes, mean systolic blood pressure and hypoglycemia as covariates. Model 7 included the number of 1–2 h post‐lunch blood glucose (1–2h‐PLBG) measurements (ln‐transformed), age, sex, duration of diabetes, mean systolic blood pressure and hypoglycemia as covariates. Hypoglycemia was defined as the presence of fasting or casual blood glucose levels <70 mg/dL (3.9 mmol/L) at least once during the 2‐year period from the first visit. CI, confidence interval; HbA1c, glycated hemoglobin; HR, hazard ratio.