[Furface]

Simple answer is "Yes". Less simple answer is "It depends".
In a perfect world, your bow is tuned to your arrows, which have the correct spine for your bow. The have a zen-like relationship of perfect harmony. Up the poundage of the bow, and the spine of your arrows becomes too weak, leading to performance deterioration. In a perfect world, you would simply buy new arrows to match your new limbs. In a less than perfect world, a proportion of the deterioration can be countered by tuning your bow; there are also ways (I believe) of effectively stiffening your arrows. This may be enough for you to get acceptable results until you save up the pennies for the new arrows.