This depends entirely on how the Rogue acquired Combat Advantage in the first place. But the short version is: If the Rogue would still have CA if it was their turn instead of yours...then yes. If not, then no.
The most common way that a Rogue can gain Combat Advantage is by flanking their opponent. So if you grant the Rogue an extra attack while they are flanking an opponent, they have Combat Advantage. However, if their opponent moved so they were no longer flanked by the Rogue, the Rogue no longer has CA. This even means that if the Rogue didn't have CA on their turn, but then you move to flank the target the Rogue is attacking and grant the Rogue an attack...they now have CA because they are attacking a flanked target.
This applies to all of the common status-effect methods by which you can gain Combat Advantage. If the target was blinded on the Rogue's turn, thus granting CA...if they are still blind on your turn when you give the Rogue an Extra Attack, then the Rogue still has CA. If not, then they do not.
One particular point worth addressing is Stealth. If the Rogue gained Combat Advantage by being Hidden from their target on their turn, but did not re-establish Stealth by the end of their turn...then they are no longer gaining CA from being hidden because, simply put, they aren't hidden anymore.
Most Rogue Powers that grant Combat Advantage (such as Adaptable Flanker) specify how long they last (i.e. "Until the end of your next turn"), so those answer for themselves.
I cannot possibly cover every possible way in which you can gain Combat Advantage, but you can address them all by asking the same question I did:
"If it was the Rogue's turn again, would they have CA against this target?"