The correlation between diabetic retinopathy and blood pressure was analyzed in 742 type II diabetic patients. Systolic and pulse blood pressures were significantly higher in the patients with retinopathy than in those without (mean systolic pressure 142 vs. 139 mmHg, P < .01; mean pulse pressure 60.5 vs. 56.4 mmHg, P < .001). There was no difference in the diastolic blood pressure between these two groups. The correlation between blood pressure and the components of retinopathy (including microaneurysms, hemorrhages, and exudates) was also analyzed. Even when the patient with microaneurysms or dot hemorrhages, blot hemorrhages, or hard or soft exudates were separately evaluated, systolic and pulse blood pressures were higher in those with one of these diabetic changes than in patients without them.
To avoid the influence of nephropathy, the patients were divided into nonproteinuric or proteinuric groups. In the nonproteinuric group, pulse blood pressure was higher in patients with retinopathy than in those without. In the proteinuric group, systolic blood pressure was also higher in patients with retinopathy than in those without. However, these observed differences in blood pressure were slight after the division of the patients. With respect to the components of retinopathy, systolic and pulse blood pressures were significantly higher in the patient with blot hemorrhages than in those without in both nonproteinuric and proteinuric groups (nonproteinuric: systolic pressure 142 vs. 137 mmHg, P < .005, and pulse pressure 60.4 vs. 55.5 mmHg, P < .001; proteinuric: systolic pressure 155 vs. 146 mmHg, P < 0.01, and pulse pressure 69.0 vs. 63.5 mmHg, P < .05) In regard to other components (microaneurysms, dot hemorrhages, or hard or soft exudates), no significant difference was found in blood pressure when analyzed in both nonproteinuric and proteinuric patients.
Systolic, diastolic, and pulse blood pressures did not correlate with blood glucose level in any of our patients. These data revealed that systolic hypertension is a risk for diabetic retinopathy, especially for blot hemorrhage.