Association of glaucoma with central blood pressure waveform parameters

Background. Glaucoma is theorised as being associated with blood pressure parameters, though studies to date have not been consistent in their findings. This study aimed to investigate peripheral and central blood pressure parameters in definite glaucoma sufferers. Methods. 107 glaucoma subjects were studied, where glaucoma was strictly defined as definite neuroretinal rim loss assessed by stereo disc assessment, with corresponding confirmed field defect. Brachial systolic/diastolic pressures and radial pressure waveforms were measured and the central pressure waveform calculated using a validated transfer function (Sphygmocor, Atcor Medical). Results were compared with age/sex matched controls, free of glaucoma. Results. Self-reported white coat hypertensives were excluded (n7). The average age of the cohort was 6612 years, with a BMI of 265 kg.m-2. Central pulse pressures were lower in the glaucoma group (glaucoma 411, control 471 mmHg, p0.001). However, pulse pressure amplification was higher in the glaucoma group (1.320.01 vs 1.240.01, p0.001). This effect may be related to the significantly higher heart rate in the glaucoma sample group (691, 661 bpm, p0.05). The subendocardial viability ratio (SEVR), though not a parameter directly associated with blood flow in the eye, was higher in the glaucoma group than in controls (1.660.31 , 1.530.30 respectively, p0.01). However, SEVR was negatively associated with glaucoma disease progression (progression 1.580.25, stable 1.720.33, p0.05). Conclusions. Parameters of the pulsatile central blood pressure waveform are associated with glaucoma, and with glaucoma disease progression. This may be due to blood flow to the eye, especially during diastole, in a positive pressure (intraocular) environment. Further work is required to associate these systemic parameters with local ocular blood flow conditions.