It is shown that the correct power-law decay predictions for the long-time relaxation of reversible diffusion-influenced reactions, which were recently derived by Gopich, Ovchinnikov and Szabo with a hydrodynamic approach [Phys. Rev. Lett. 79, 922 (2001)] can also be obtained with an appropriate mode-coupling approximation after rephrasing the problem into a memory function approach. This is explicitly demonstrated for association-dissociation in the extreme situations of the target and trapping model. By constructing the memory function approximations via the solution of self-consistent equations for the relevant time-correlation functions, this method paves the way for a systematic study of higher reactant concentration effects. Moreover, the fact that the correlation decay equations derived have the typical form for stochastic approaches facilitates comparison with other theoretical concepts.