In order to help PCa patients manage adverse effects of ADT, we need to know all the ways that ADT affects the body. As such, we try to track all the literature suggesting ADT side effects no matter how obscure those side effects might be.
A new paper out of Turkey looked at the effect of ADT on various aspects of the eyes of 57 patients. This included high resolution CAT scans, which allowed the researchers to assess details, such as: the size of small muscles that move our eyes to redirect our gaze, the fat around the eyes, and the thickness of the optic nerve. The researchers found that 12 months or more of ADT caused a decrease in the size of the muscles that move the eye and an increase in the fat around and behind the eye. This extra fat pushed the eye forward slightly stretching and thinning the optic nerve.
At first glance, this sounds scary. Thus, it is important to point out the authors found no evidence of clinical changes in vision. They noted that these changes were “remarkably lower” than what would be considered clinically significant.
The change in fat was approximately 12% over baseline. Researchers pointed out this was in the range of what is commonly reported as overall weight gain for men on ADT for a year or more. The change in muscle mass was similarly consistent with what is average for men on ADT long term. Typically, though, when we think about changes in fat and muscle with prolonged use of ADT, we think about weight gain around the abdomen and weaker legs from loss of muscle mass in the extremities
It is not surprising that the same changes happen on a much smaller scale for the tiny muscles and fat around the eyes. Indeed, these results are what we would have predicted from what we know about ADT’s effects on the body in general. It is good to note that although the sample size was not large, there is no indication that these changes around the eye affect vision in any significant way
Reference:
Sonmez H, K, Sonmez G, Doğan S, Horozoglu F, Demirtas A, Evereklioglu C (2022) Effects of Androgen Deprivation Therapy on the Extraocular Muscles, Retrobulbar Orbital Fat and the Optic Nerve in Patients with Prostate Cancer. Ophthalmic Res. doi: 10.1159/000527387