Synonym for "Fellow Sufferers"?

They agreed to stay connected for hours in their provisional support group, looking for answers in their counterparts.

I want to change the bold part to say that they all shared the same problem. Might end up using one of the above, but I feel like I need some more options to weigh in.

Edit for context: they all share the same rare cognitive impairment

Solution 1:

There's the straightforward co-sufferer: "one who suffers with another." (Free Dictionary)

Solution 2:

Personally, I think it's just a little bit "dated, formal, poetic", but OED has

fellow noun 5a
One who shares with another in any attribute; one belonging to the same class
[emphasis mine]

Note that the near-equivalent peer (someone/something of equal worth or quality) usually implies equality in respect of something desirable, so it wouldn't necessarily work for OP's context (unless you really admire people who go to support groups! :)

But although in principle you could use unqualified fellows to mean people with the same drawback [or advantage, background, etc.] as you), in practice most people would go for

fellow sufferers

(Hyphenated or not - but as the NGram link shows, usually these days we don't.)