Macular pigment optical density and visual quality of life

There is robust evidence that higher macular pigment concentrations help reduce both veiling and discomfort glare in patients with or without ocular disease. We investigated whether there was also a relationship between macular pigment optical density (MPOD) and patient surveys about glare or ocular discomfort.

We measured MPOD psychophysically in 23 healthy subjects and administered the National Eye Institute Visual Functioning Questionnaire (VFQ-25). Responses for each survey question were sorted from low (no limitation) to high (very severe limitation). The median response for each question was determined, and independent t-tests were performed on the mean MPOD values for survey responses above and below the median. We also performed a non-parametric correlation analysis between MPOD and survey responses.

While the median response was "no limitation" for most (22 of 25) survey questions, responses were slightly higher for two questions concerning ocular discomfort and one question related to driving at night. MPOD levels were significantly higher in subjects that reported no discomfort in or around their eyes than in those that reported mild discomfort. There was also a trend toward higher MPOD levels in subjects who reported that pain in or around their eyes never limited their activity as well as in subjects who reported no difficulty driving at night.

These preliminary findings are consistent with the well-established discomfort and glare hypotheses for MPOD. The current findings on subjective ocular discomfort in the absence of glare deserve further study.