Does a person with MS have a greater chance of also having Narcolepsy (with/without Cataplexy)?

I not only have PPMS but also narcolepsy with cataplexy and what started out as Severe Obstructive Sleep Apnea that has gone onto Complex Sleep Apnea (I needed to have a trach tube put in in 2005 that is still in place and will never be removed). While researching all three diseases I found out they are all autoimmune diseases. Besides these I have Fibromyalgia and about 29 or 30 other diagnoses. Some due to the MS but many due to family history and living on a fixed income my whole adult life and not being able to buy the right foods to keep my weight down (and not being able to exercise well). It seems to me that these three diseases must somehow be "related" or affected by each other.