I am not sure I understand the question as they both have very different symptoms but, I was told by my rheumatologist that I only have one immune system so of course there’s a connection. In fact I had my colon removed because of 30 years of ulcerative colitis and when I told him that, that was his reply. Also if you have one autoimmune disease you are more likely to get another than the general public. I also have a third being MS

They have given me the diagnosis of undifferentiated mixed connective tissue disease, because it is systemic and I have symptoms and blood work that is not definite. Although they tell me they are sure mixed connective tissue/ RA /fibromyalgia. It is frustrating.

Why would the Dr give you any medication if they don't know 🤔 exactly what to treat.

I went to 3 specialists who were rheumatologist and they could not diagnose my RA. All they told me was I had a connective tissue disease, but didn't know which one!! I was frustrated and during that time, they had me on many medications that messed with my system.

Yes and it was frustrating in the beginning phase of my diagnosis. After all these years, I still experience frustration, impatience with myself and anger when I can't move as quickly as I used to.