I would imagine that this house also had braces added from the roof rafters to the ceiling joist...hopfully to the top of a load bearing walls. If there is no serious cracks in the ceiling or walls I just mention the additional bracing. If there are shims installed to level the roof sheathing then at most I would recommend adding a 2X4 along the side of the rafter for more support. A 37 year old house is not going to be perfect.