Orthostatic blood pressure variability is associated with lower visual contrast sensitivity function: Findings from...

Area of Science:

• Ophthalmology and Visual Science
• Cardiovascular Health
• Autonomic Nervous System Function

Background:

• Hypertension is a known cause of vascular end-organ damage.
• Abnormal blood pressure (BP) regulation, including orthostatic hypotension, is linked to cardiovascular events.
• The eye's susceptibility to BP dysregulation depends on ocular circulation autoregulation.

Purpose of the Study:

• To investigate the relationship between abnormal BP stabilization phenotypes after orthostasis and contrast sensitivity.
• To determine if visual function, measured by contrast sensitivity, is associated with specific orthostatic BP behaviors.

Main Methods:

• Cross-sectional study using data from The Irish Longitudinal Study on Ageing (TILDA).
• Defined 4 orthostatic BP phenotypes (normal, hypotension, hypertension, variability) from beat-to-beat BP measurements.
• Assessed contrast sensitivity using a Functional Visual Analyzer in 4289 adults aged ≥50 years, with multivariable regression analyses.

Main Results:

• Systolic orthostatic blood pressure variability was significantly associated with worse contrast sensitivity.
• This association persisted in primary and sensitivity analyses, even after adjusting for cardiovascular risk factors and retinal pathologies.
• Adjusting for clinical cataract reduced the observed association by 18%.

Conclusions:

• Orthostatic blood pressure variability is independently associated with reduced contrast sensitivity.
• This suggests orthostatic BP variability may serve as a cardiovascular biomarker for early ocular pathology.
• The findings highlight a potential link between autonomic BP regulation and subtle visual function deficits.