Correlation of Pupil to Limbus Diameter Ratio with Blood Pressure and Heart Rate among Parkinson’s Disease Patients

Introduction: Variation in blood pressure and heart rate is observed in patients with parkinson’s disease. Pupil to Limbus Diameter (PDL) ratio is one of the emerging autonomic functions. The studies measuring the autonomic functions of parkinson’s patients are sparse. Aim: To observe the correlation of the PLD ratio with blood pressure and pulse rate among parkinson’s disease patients. Materials and Methods: This observational study was conducted among 31 parkinson's disease patients attending Outpatient Ward of General Medicine Department at Ruxmaniben Deepchand Gardi Medical College, Ujjain, Madhya Pradesh, India, from 1st March 2021 to 1st November 2021. Pupil to limbus diameter ratio was recorded using the two-box method. Data was analysed using Statistical Package for Social Sciences (SPSS) version 20.0. Pearson’s correlation was used to observe the correlation. A p-value less than 0.05 was considered significant. Results: The mean age of the participants was 61.9±13.07 years. The mean PLD ratio of the left eye was 0.343±0.042. There was a significant positive correlation between the PLD ratio of the left and right eye with blood pressure in males. There was a positive correlation between pulse rate also with PLD ratio of the left and right eyes. However, it was not significant. Conclusion: There was a significant positive correlation of the PLD ratio with blood pressure and pulse rate in males, but negative correlation was observed between the PLD ratio of the left eye with systolic and diastolic blood pressure in females. The study results support the need for further detailed studies in this area to investigate further details of this correlation observed.