I am a Viet Nam vet who received a combined 60% rating in 2006. This includes Diabetes Mellitus Type 2, Tinnitus and PTSD. I have had many sleepless nights since being discharged in 1971. My physician wants me to have a sleep study done for Sleep Apnea. Assuming I am diagnosed with Sleep Apnea could I submit a claim with Sleep Apnea as secondary to either the Diabetes or the PTSD? Suppose I filed a claim as Sleep Apnea aggravated by PTSD? Is this something that would be worth pursuing? Thanks for any comments.