A study out of Mass Eye and Ear found several factors that affect dark adaptation in AMD patients.
What do we know?
AMD patients have worse dark adaptation than non-AMD patients.
The going theory is rods degenerate earlier and more severely than cones and that AMD initially affects the parafoveal region (that has more rods than cones). Progressive loss of rods is associated with normal aging, but it seems to be more pronounced in subjects with AMD.
Less rods = worse dark adaptation.
What did this study tell us?
Other factors in combination with AMD contribute to reduced dark adaptation. They are, a higher body mass index, alcohol intake, a family history of the disease and here is the zinger, AREDS supplements.
Why would using AREDS supplements make dark adaptation worse?
This finding is what researchers call “difficult to interpret”. However, they note that the patients using AREDS supplements also had a higher number of large drusen, “likely contributing to their worse dark adaptation outcomes.” (via)