Lower Right Arm And Hand Numbness, Pricking Sensation While Sleeping. Using Wrist Guard. Causes?

For the past 5 years I have been experiencing my lower right arm and hand falling asleep , with pins & needles while I ve been sleeping. It wakes me up constantly. I ve changed positions to ensure I am not cutting off circulation. I have also learned that if I use a wrist guard to keep my wrist straight, it helps, but still occurs often. Usually, the only thing that truly relaxes it is to get up & get the day started. What do you suspect could be going on, and should I be concerned that this is a warning sign of something seriously wrong?