Abstract
Abstract: :
Purpose: In the Collaborative Normal Tension Glaucoma study (CNTG), patients with a positive cardiovascular history (including hypertension) and NTG did not benefit from IOP lowering .1 We investigated whether patients with NTG and systemic hypertension (HTN) exhibited fluctuations on 24–hour ambulatory blood pressure monitoring (ABPM) that were not present in NTG patients without systemic HTN that could explain this lack of a response to treatment. Methods:35 NTG patients underwent 24–hour ABPM. 18 of these 35 patients were diagnosed with HTN. The highest percent of fluctuation in systolic and diastolic blood pressures from daytime to nighttime was calculated as systolic fluctuation (SF) and diastolic fluctuation (DF). In addition, intra–phase fluctuations in blood pressure occurring only during the daytime phase or the nocturnal phase was calculated as nocturnal systolic fluctuation (NSF), nocturnal diastolic fluctuation (NDF), daytime systolic fluctuation (DSF), and daytime diastolic fluctuation (DDF). Results:Differences in blood pressure fluctuations were statistically significant between NTG patient with HTN and those without HTN for the following parameters respectively: DSF: 24.39 ± 11.66, 17.12 ± 5.52, p=. 013; NDF: 29.89 ± 9.73, 23.25 ± 7.56, p=. 016. Conclusions: NTG patients with HTN had significantly higher fluctuations in their nocturnal diastolic and daytime systolic blood pressures when compared to NTG patients without HTN. These fluctuating blood pressure parameters appear to be a risk factor for glaucoma progression and may explain the lack of response to IOP lowering in the CNTG study.
Keywords: clinical (human) or epidemiologic studies: risk factor assessment