Autonomic Dysfunction and Blood Pressure in Glaucoma Patients: The Lifelines Cohort Study

ABSTRACT:

Purpose: 
We investigated relationship of glaucoma with measurements related to autonomic dysfunction, including heart rate variability (HRV) and blood pressure (BP). 
Methods: 
Glaucoma was defined using a questionnaire-based algorithm for 86,841 LifeLines Cohort Study participants. Baseline HRV (root mean square of successive differences [RMSSD]) was calculated from resting electrocardiograms; systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP), and pulse pressure (PP) were oscillometric-based measurements. We used a generalized linear mixed model, adjusted for age, age square, sex, body mass index, and familial relationships to assess the relationship of baseline HRV and BP (continuous and quartiles), hypertension, and antihypertensive medication with glaucoma at follow up (median, 3.8 years). 
Results: 
The odds ratio (OR) of glaucoma was 0.95 (95% confidence interval [CI], 0.92–0.99) per unit increase in log-transformed RMSSD (in ms), indicating that autonomous dysfunction (low HRV) is associated with a higher risk of glaucoma. Per 10-mm Hg increase in BP, we found ORs of 1.03 (95% CI, 1.01–1.05; P = 0.015) for SBP, 1.01 (95% CI, 0.97–1.05; P = 0.55) for DBP, 1.03 (95% CI, 1.00–1.06; P = 0.083) for MAP, and 1.04 (95% CI, 1.01–1.07; P = 0.006) for PP. The OR for the lowest versus highest RMSSD quartile was 1.15 (95% CI, 1.05–1.27; P = 0.003). The ORs for the highest versus second quartile were 1.09 (95% CI, 0.99–1.19; P = 0.091) for SBP and 1.13 (95% CI, 1.02–1.24; P = 0.015) for PP. Glaucoma was more common among hypertensives (OR, 1.25; 95% CI, 1.16–1.35; P < 0.001); among those using angiotensin-converting enzyme (ACE) inhibitors (OR, 1.35; 95% CI, 1.18–1.55; P < 0.001); and among those using calcium-channel blockers (OR, 1.19; 95% CI, 1.01–1.40; P = 0.039). 
Conclusions: 
Low HRV, high SBP, high PP, and hypertension were associated with glaucoma. Longitudinal studies may elucidate if autonomic dysregulation and high BP also predict glaucoma incidence.