The VA is asking for "a million veterans" to participate in a survey about health and mental condition. The survey can be found here.
Knowing what the Jugears administration has already done to our veterans, I would just file the letter in the circular file, not even mark :"I do not want to participate".
Telling the government that you have periods of "feeling blue" or are suffering from PTSD could easily get you listed as a "risk" and barred from owning a firearm. Admitting to chronic pain could easily have the same result.