Value of retinal examination in hypertensive encephalopathy

The presence of grade III or IV hypertensive retinopathy (HRP) is considered to distinguish hypertensive urgencies from emergencies. However, case-reports suggest that these retinal changes may be lacking in patients with hypertensive encephalopathy. To assess the frequency of grade III and IV retinopathy in this hypertensive emergency, we conducted a retrospective cohort study. We retrieved 162 patients with malignant hypertension and 34 patients (17%) fulfilled the predefined criteria for hypertensive encephalopathy. Data on retinal examination were incomplete for 6 patients (18%), thus leaving 28 patients who were analysed for the presence or absence of grade III and IV HRP. In 9 (32%) patients with hypertensive encephalopathy, grade III or IV HRP was absent, 11 (39%) patients presented with grade III and 8 (29%) patients with grade IV retinopathy. Patients without retinal abnormalities were on average 13 years younger (P=0.05), more often black (P=0.02) and displayed lower blood pressure (BP) values (P=0.04 for systolic and diastolic BP). A substantial proportion of patients with hypertensive encephalopathy lack grade III or IV HRP. This suggests that the decision to admit these patients should not only rely on the presence of grade III and IV retinopathy alone, but should also include a careful neurological examination.