The practice of mindfulness meditation is traditionally done with eyes closed. Exceptions to this are often made for those who have anxiety or panic attacks, who have been physically or sexually abused as children or attacked as adults, and those who suffer from PTSD from any source.  Starting with a soft focus or eyes open and focused on a lower part of the body such as the feet often feels safer than eyes closed.  Over time, this usually changes so that meditating with eyes closed becomes comfortable.