Patients with high blood pressure may have more glaucomatous damage to the macula. Photo: Getty images.

Traditional glaucoma monitoring methods such as disc photography and 24-2 or 30-2 visual fields (VFs) tend to miss damage within the macula, research suggests. In an effort to assess the sensitivity to glaucomatous progression of different testing strategies, researchers recently found that macular structural and functional parameters are more sensitive to intraocular pressure (IOP) when compared with more conventional parameters. While hypertension (HTN) was not significantly associated with progression using any parameter, macular structural and functional parameters had a better goodness-of-fit to model progression and may be useful as endpoints.

The prospective, longitudinal study enrolled 191 eyes of 119 glaucoma patients (38% with self-reported HTN). Patients were tested with 10-2 and 24-2 VFs and spectral-domain OCT obtained at four- to six-month intervals. IOP from each visit was collected. Regression analysis was used to test the relationship of VF and OCT with hypertension diagnosis. 

Mean follow-up IOP was most associated with the following OCT parameters: global macular ganglion cell layer (GCL), inferior macula GCL, mean macular vulnerability zone GCL and mean macular less vulnerable zone GCL. It was also most associated with the following VF parameters: 10-2 pattern standard deviation and 10-2 mean deviation. There was no significant difference in rates of progression between HTN and non-HTN patients for any OCT or VF parameter. Models with the best goodness-of-fit for the relationship between HTN and progression were the same as those observed for IOP.

The findings may be useful to doctors “who often rely on self-reported information about HTN in their practices,” the study authors concluded. “These factors may explain why macular parameters demonstrated superior goodness-of-fit when considering HTN but were not found to be statistically significant. Nevertheless, our findings suggest that systemic blood pressure may play a role in glaucomatous damage to the macula.”