VCA Board Certified Feline Specialist Veterinarian Irene Nakaoka DVM, DABVP explains that many senior cats have Degenerative Joint Disease, a form of arthritis, which can make it painful for them be as active as before. She talks about signs to look out for, such as reluctance to jump on or off the bed or difficulty to get in and out of the litterbox, and advises maintaining a heathy weight and regular check ups with your veterinarian.