The use of cholanis in the mi-shebeirach for the cholim

There's a discussion over at the End The Madness message board about use of the word "cholanis" in the mi shebeirach for the cholim. (The thread is located in the Madness Watch forum, under the title "New Degree of Separation"). In a comment there, I posted:
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In a discussion of the matter at mail-jewish (38:48) , someone quoted the Meiri on Kesubos 51b who explains that a cholanis is borderline sick (cholah v'ainah cholah) while a cholah is someone who's outright sick. On MJ 38:41, someone noted that Siddur Tefillah Yesharah (aka the Berditchever siddur) uses the word cholanis in the mi shebeirach, perhaps out of a desire not to say that someone is outright sick and therefore needs a greater yeshuah in order to be healed.

One can ask why they use the nonparallel terms of choleh and cholanis; perhaps cholani is never found in divrei Chazal, so the authors of this version of the mi shebeirach did not feel comfortable inventing it. (On a side note, I'd be curious to know when the original text of this mi shebeirach was composed, in order to determine how much of an innovation the word change from cholah to cholanis (or vice versa?) really was).