Abstract
Purpose :
Recent discovery of the ipRGC, a small group of melanopsin-containing retinal photoreceptors, has supported the critical role of the eye in the regulation of non-visual physiologic functions such as sleep and pupil reactivity. Here, we present a preliminary analysis to characterize the ipRGC-mediated PLR in an epidemiologic cohort.
Methods :
We are conducting a cross-sectional study to collect pupil reactivity in a subset of participants in the 10-year follow up examination of the Beaver Dam Offspring Study (BOSS), an established, large longitudinal epidemiologic, multi-sensory study of aging. The pupil reactivity is recorded using a binocular infrared pupillometer (DP2000 Human Laboratory Pupillometer, Neur-Optics, Inc., Irvine, CA). The stimulus consists of a pair of 1-sec red (640±10 nm) and blue (467±17 nm) light stimulus at the intensity of 2.0 log lux. The ipRGC-mediated PLR is calculated as post-illumination pupil response (PIPR) at 6-sec after termination of the 1-sec light stimulus. Sleep quality is assessed using a modified, semi-quantified Wisconsin Sleep Cohort Study questionnaire. Cognitive function testing consists of Mini-mental State Examination (MMSE), Trail Making Test A and B, Rey’s Auditory Verbal Learning Test (AVLT), Digit Symbol Substitution Test, and Verbal Fluency Test (F, A and S).
Results :
208 BOSS participants were included in this preliminary analysis, with age ranging from 37 to 80 years (mean±SD: 59.4±9.5). The baseline pupil diameter decreases with increasing age (linear regression, y=-0.041x+7.777, R2=0.19). The percent PIPR demonstrates a modest age-related decline, and a stronger association with baseline pupil diameter (linear regression, y=0.038x+0.042, R2=0.20).
Conclusions :
The preliminary analysis of this selected BOSS cohort demonstrated a modest trend of age -related decline in percent PIPR and a positive correlation between the percent PIPR with baseline pupil diameter. The correlation of the ipRGC-mediated PLR with sleep and cognitive measurement will be explored further upon completion of data collection in Dec 2017.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.