In English, "anyway" is sometimes used to change the subject of conversation.
Anyway, how are you?
Is the corresponding German word "sowieso"?
Sowieso, wie geht's dir?
Are there other options?
My favourite words for changing the subject:
The überhaupt can be used when you want to add the nuance that it just occured to you that you should have asked this earlier. My Sprachgefühl tells me that eigentlich (or überhaupt)is what really effects the topic change, like saying "this is what's important now".
Then there is:
The subsentence stress has to be on da. I think it is pretty neutral, conveying no criticism of the old topic.
The hier can be used as some sort of interjection to "soften the blow", but it's not mandatory and it can also be used in combination with the other suggestions. The version with the hier is somewhat colloquial.
Another one would be:
This one is especially good for "rescuing" yourself if you mixed up facts and want to close the discussion until you have looked them up again (which might be never). But: this can sound sloppy, only recommended for colloquial use.
If you want something really short, you could also use:
This one is a bit difficult because much depends on tone when using naja. This might sound a bit critical of whatever was said before if not said in a light, friendly tone, with stress on the ja. (Don't say nah-ja. That might lead to more discussion.)
Generally, some interjection (ja, hm, ach ja, naja, mm, hier,...) in combination with eigentlich or überhaupt should be enough, the longer versions are optional.
The other possibilities mentioned in the other answers do not really sound natural to me (native speaker). But that might depend on region, profession ...
I think one of them can be salvaged:
Although this does not really change a subject, but rather sidetracks it temporarily (like by the way maybe) with the intention of coming back to the original topic afterwards.
Sowieso is completely wrong in this context. It just does not make any sense.
I'd translate this to:
No, I wouldn't use "Sowieso". While the sentence might be understood, the word is commonly used to emphasize the meaning of the rest of the sentence:
I would use something like
Or, to emphasize that one has forgotten to ask about it: