INFLUENCE OF MENTAL AND PHYSICAL STRESS O N INTRAOCULAR-PRESSURE - A PILOT-STUDY

Background The aim of the present study was to examine the influence o f phasic stressors on intraocular pressure (IOP). Subjects and methods We exposed 15 ophthalmologically and systemically healthy non-smoking subjects (m:f=8:7; mean age 25.4 years) to both bicycle ergometry phy sical stress and a computer-game psychological stress. IOP, blood pres sure, and subjective stress were measured. To adjust for between-subje ct variance, we calculated intra-subject z-scores based on IOP values. Because of the habituation occurring during repeated tonometric measu rements, we tested the significance of the difference between the obse rved and expected IOP z-values for each of the stressors. The expected IOP value was the mean of the pre- and post-stress relaxation-period values. Student's t-tests were used to assess the impact of the stress ors on blood pressure. Results Both stressors increased the systolic b lood pressure, but only under mental stress was the intraocular-pressu re increase statistically significant (p = 0.048). Discussion The sele ctive increase in intraocular pressure during mental stress by similar reaction of blood pressure to both stressors is a hint for possible d ifferent regulation circuits in the autonomic nerve system for intraoc ular- and blood pressure, respectively. Additionally, it was possible to demonstrate that mental stress could lead to a rise in intraocular pressure.